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Cardiovascular disease onset in old people with severe hypercholesterolemia

      Highlights

      • Familial hypercholesterolemia (FH) genetic variants are implicated in higher atherosclerotic cardiovascular disease risk (ASCVD) risk even in severe hypercholesterolemia.
      • Risk is greater in young people.
      • Lipid lowering therapy may change natural history of hypercholesterolemia in old people.
      • In old severe hypercholesterolemic patients, FH variants were not associated with new ASCVD disease onset.
      • Previous cardiovascular disease was independently associated with new ASCVD onset.

      Abstract

      Background and aims

      Familial hypercholesterolemia (FH) variants are associated with higher atherosclerotic cardiovascular disease risk (ASCVD) even when compared with other forms of severe hypercholesterolemia, especially in young people. Lipid lowering therapies (LLT) may change hypercholesterolemia natural history. This study aimed at evaluating factors associated with occurrence of ASCVD in old severe hypercholesterolemics diagnosed or not with FH and undergoing LLT.

      Methods

      Hypercholesterolemic individuals ≥60 years participating on a genetic cascade screening for FH were divided in 4 groups (2 × 2) according to the presence (variant+) or not (variant-) of FH genetic variants and previous ASCVD (ASCVD+ and ASCVD-). Biomarkers associated with new incident ASCVD events were tested using Cox models. Continuous data shown as medians (%25; %75).

      Results

      From 4,111 genotyped individuals, 377 (9.1%) were elderly [age 66 (63; 71) years], 28.9% males, 42.7% variant+, 32.1% with previous ASCVD, LLT duration 9 (5; 16) years, and on treatment LDL-cholesterol 144 (109; 200) mg/dL. After 4.8 (7; 3) years of follow up there were 47 incident events (12.4%, 2.7% patient/year). The annualized event rates were 0.8% (95% CI 0.36%; 1.70%), 2.3% (95% CI 1.3%; 4.1%), 5.2% (95% CI 2.8%; 9.7%) and 6.3% (95% CI 4.0%; 10.0%) respectively for groups variant-/ASCVD-, variant+/ASCVD-, variant-/ASCVD+ and, variant+/ASCVD+ (p log rank p < 0.001). Only presence of previous ASCVD was independently associated with incident ASCVD [hazard ratio 3.236 (95%CI 1.497–6.993, p = 0.003)]. No interaction was found for previous ASCVD and variants.

      Conclusions

      In old severe hypercholesterolemic individuals undergoing long-term LLT previous ASCVD was associated with incident events while FH causing variants were not.

      Graphical abstract

      Keywords

      1. Introduction

      People with severe hypercholesterolemia usually defined by Low Density Lipoprotein Cholesterol (LDL-C) concentrations 190 mg/dL are considered at high risk for development of atherosclerotic cardiovascular disease (ASCVD) [
      • Mach F.
      • Baigent C.
      • Catapano A.L.
      • et al.
      ESC/EAS Guidelines for the management of dyslipidaemias: lipid modification to reduce cardiovascular risk.
      ]. Familial hypercholesterolemia (FH) is a autosomal co-dominant monogenic disorder affecting approximately 1 in 310 individuals in the general population worldwide [
      • Hu P.
      • Dharmayat K.I.
      • Stevens C.A.T.
      • et al.
      Prevalence of familial hypercholesterolemia among the general population and patients with atherosclerotic cardiovascular disease: a systematic review and meta-analysis.
      ,
      • Beheshti S.O.
      • Madsen C.M.
      • Varbo A.
      • et al.
      Worldwide prevalence of familial hypercholesterolemia: meta-analyses of 11 Million subjects.
      ], characterized by elevated plasma LDL-C from birth, and thus an increased risk of premature coronary heart disease (CHD) [
      • Defesche J.C.
      • Gidding S.S.
      • Harada-Shiba M.
      • et al.
      Familial hypercholesterolaemia.
      ]. Standardized CHD mortality ratios are four to five-fold higher in untreated FH in comparison with the general population [
      Mortality in Treated Heterozygous Familial Hypercholesterolaemia: Implications for Clinical Management. Scientific Steering Committee on Behalf of the Simon Broome Register Group.
      ].
      Although severe hypercholesterolemia (≥190 mg/dL) increases risk of CHD, the presence of an FH causing variant implicates in additional risk. In the study of Khera et al., hypercholesterolemic individuals with and without an FH variant presented a 22-fold and 6-fold higher risk of coronary artery disease compared to normocholesterolemic individuals [
      • Khera A.V.
      • Won H.H.
      • Peloso G.M.
      • et al.
      Diagnostic yield and clinical utility of sequencing familial hypercholesterolemia genes in patients with severe hypercholesterolemia.
      ]. Typically, if left untreated cardiovascular events usually occur respectively in the fourth and fifth decades in men and in women with heterozygous FH [
      • Mata P.
      • Alonso R.
      • Perez-Jimenez F.
      Screening for familial hypercholesterolemia: a model for preventive medicine.
      ] however, this incidence is variable and depends not only on LDL-C but also other risk biomarkers [
      • Miname M.H.
      • Santos R.D.
      Reducing cardiovascular risk in patients with familial hypercholesterolemia: risk prediction and lipid management.
      ].
      Of interest FH causing variants are not frequently encountered in old people [
      • Lacaze P.
      • Sebra R.
      • Riaz M.
      • et al.
      Familial hypercholesterolemia in a healthy elderly population.
      ] and since FH is a genetic disease the study of affected old individuals may provide a good opportunity to understand its natural history. In the Spanish FH registry (SAFEHEART), individuals older than 60 years had a 4.27-fold (95% CI 1.6–11.48) increased risk of ASCVD in comparison with non-affected old age counterparts after adjustment for confounders [
      • Mata N.
      • Alonso R.
      • Badimon L.
      • et al.
      Clinical characteristics and evaluation of LDL-cholesterol treatment of the Spanish familial hypercholesterolemia longitudinal cohort study (SAFEHEART).
      ].
      Contemporary hypercholesterolemia populations live a shift on the natural history of CHD due to the availability of lipid lowering therapy (LLT), mainly statins, over the last 30 years [
      • Versmissen J.
      • Oosterveer D.M.
      • Yazdanpanah M.
      • et al.
      Efficacy of statins in familial hypercholesterolaemia: a long term cohort study.
      ,
      • Santos R.D.
      • Coutinho E.R.
      Resilience of individuals with familial hypercholesterolaemia to develop atherosclerotic cardiovascular disease: lessons learned from the elderly.
      ,
      • Mundal L.J.
      • Igland J.
      • Veierod M.B.
      • et al.
      Impact of age on excess risk of coronary heart disease in patients with familial hypercholesterolaemia.
      ,
      • Neil A.
      • Cooper J.
      • Betteridge J.
      • et al.
      Reductions in all-cause, cancer, and coronary mortality in statin-treated patients with heterozygous familial hypercholesterolaemia: a prospective registry study.
      ]. However, old people with hypercholesterolemia including FH were probably exposed to high LDL-C levels before statins became widely available for treatment and thus may have suffered the consequences of delayed treatment onset i.e., CHD events. In addition, they commonly have other risk factors that appear with ageing (e.g., high blood pressure, obesity, and type 2 diabetes mellitus) or were more frequent in the past such as smoking [
      • Lloyd-Jones D.M.
      • Leip E.P.
      • Larson M.G.
      • et al.
      Prediction of lifetime risk for cardiovascular disease by risk factor burden at 50 years of age.
      ,
      • Jansen A.C.
      • van Aalst-Cohen E.S.
      • Tanck M.W.
      • et al.
      The contribution of classical risk factors to cardiovascular disease in familial hypercholesterolaemia: data in 2400 patients.
      ].
      Overall, despite FH presence implicates accrued ASCVD risk, many affected individuals do not develop cardiovascular disease even after reaching senescence. In a previous publication of our cohort [
      • Coutinho E.R.
      • Miname M.H.
      • Rocha V.Z.
      • et al.
      Familial hypercholesterolemia and cardiovascular disease in older individuals.
      ] comprising 198 molecularly proven elderly FH individuals (>60 years old, median age 66 years), 59.1% did not manifest previous clinical ASCVD despite higher frequency of the latter than in non-affected hypercholesterolemia controls. A recent evaluation from the SAFHEART cohort comprising 930 individuals 65-year-old (median age 73.7 years), ASCVD had not occurred in 62.2% [
      • Perez de Isla L.
      • Watts G.F.
      • Muniz-Grijalvo O.
      • et al.
      A resilient type of familial hypercholesterolaemia: case-control follow-up of genetically characterized older patients in the SAFEHEART cohort.
      ]. In that study defective LDL receptor variants, higher concentrations of High-Density Lipoprotein Cholesterol (HDL-C), younger age, female sex, absence of hypertension, and lower plasma lipoprotein(a) [Lp(a)] concentrations were independently predictive of the so-called FH resilient phenotype. However, despite this there is still scant information about biomarkers that modulate ASCVD risk in old individuals with hypercholesterolemia having or not FH and undergoing lipid lowering therapies [
      • Santos R.D.
      • Coutinho E.R.
      Resilience of individuals with familial hypercholesterolaemia to develop atherosclerotic cardiovascular disease: lessons learned from the elderly.
      ].
      The aim of this study was to evaluate factors associated with occurrence of ASCVD events, with emphasis on the impact of the FH causing molecular defects or previous ASCVD during a follow up of old individuals with severe hypercholesterolemia. Study participants had been enrolled on a FH genetic cascade screening program, underwent LLT and were followed at a lipid specialist clinic.

      2. Patients and methods

      This is a prospective analysis from the Hipercol Brasil genetic cascade screening program that included both index cases and their relatives ≥60 years old suspected of FH, evaluated from March 2011 to March 2018. For inclusion patients had to be followed for at least 6 months at the lipid clinic. The age of 60 years was chosen considering the definition of older individuals for developing regions [
      • Shetty P.
      • matter Grey
      Ageing in developing countries.
      ]. Hipercol Brasil is performed at the Heart Institute of the University of Sao Paulo Medical School Hospital (InCor-HCFMUSP) and includes individuals suspected of having FH based on high LDL-C levels (initially >210 mg/dL, but later >230 mg/dl) [
      • Jannes C.E.
      • Santos R.D.
      • de Souza Silva P.R.
      • et al.
      Familial hypercholesterolemia in Brazil: cascade screening program, clinical and genetic aspects.
      ,
      • Silva P.R.S.
      • Jannes C.E.
      • Oliveira T.G.M.
      • et al.
      Evaluation of clinical and laboratory parameters used in the identification of index cases for genetic screening of familial hypercholesterolemia in Brazil.
      ]. First-degree relatives of molecularly confirmed individuals were invited to participate in the cascade screening independently of LDL-C values or FH diagnosis. Individuals with severe hypercholesterolemia were invited to be followed at InCor's lipid clinic independently of results of the genetic test.
      FH was diagnosed if a pathogenic or a likely-pathogenic variant in LDLR, APOB or PCSK9 was found in molecular testing as previously described [
      • Silva P.R.S.
      • Jannes C.E.
      • Oliveira T.G.M.
      • et al.
      Evaluation of clinical and laboratory parameters used in the identification of index cases for genetic screening of familial hypercholesterolemia in Brazil.
      ]. Variants were described according to the recommendations of the American College of Medical Genetics and Genomics (ACMG) [
      • Richards S.
      • Aziz N.
      • Bale S.
      • et al.
      Standards and guidelines for the interpretation of sequence variants: a joint consensus recommendation of the American College of medical genetics and Genomics and the association for molecular pathology.
      ]. The Dutch Lipid Clinic Network (DLCN) score was also calculated but considering age >45 years old and the systematic molecular diagnosis used in the study, all points attributed to corneal arcus and presence of genetic variants were not considered [
      • Defesche J.C.
      • Gidding S.S.
      • Harada-Shiba M.
      • et al.
      Familial hypercholesterolaemia.
      ].
      As previously described [
      • Coutinho E.R.
      • Miname M.H.
      • Rocha V.Z.
      • et al.
      Familial hypercholesterolemia and cardiovascular disease in older individuals.
      ,
      • Jannes C.E.
      • Santos R.D.
      • de Souza Silva P.R.
      • et al.
      Familial hypercholesterolemia in Brazil: cascade screening program, clinical and genetic aspects.
      ] all subjects answered a questionnaire evaluating age (very old individuals were defined as age ≥80 years), sex, personal and family history (i.e., in first degree relatives) of early cardiovascular disease (defined as onset before 55 years old in men and 60 years old in women), hypertension, smoking (never, current, and former) and diabetes. LLT was described regarding type, duration, and intensity. High intensity LLT was defined as the use of rosuvastatin 20/40 mg, atorvastatin 40/80 mg and associations of atorvastatin 10/20 mg, rosuvastatin 10 mg or simvastatin 20/40 mg with ezetimibe 10 mg. For this analysis, we evaluated the lipid profile values at screening visit and at the last visit of follow up. Information on the use of medications that may modify the course of ASCVD was evaluated at admission to the lipid clinic and during the last follow-up visit and included aspirin, clopidogrel, angiotensin conversion enzyme (ACE) inhibitors, angiotensin receptor blockers (ARB) and beta blockers. After admittance to the lipid clinic, therapies were optimized aiming attainment of the lowest possible LDL-C concentrations.
      The presence of typical stigmas as xanthomas, corneal/senile arcus and xanthelasmas was also evaluated. Height (meters), weight (kilograms), waist and hip circumference (centimeters) were measured, and body mass index (BMI) was calculated (Kg/m2). Excess body weight was defined as a BMI ≥27 (kg/m2) as previously proposed for older populations [
      • Coutinho E.R.
      • Miname M.H.
      • Rocha V.Z.
      • et al.
      Familial hypercholesterolemia and cardiovascular disease in older individuals.
      ].
      Previous ASCVD was defined as myocardial infarction or atherothrombotic ischemic stroke, unstable or stable angina with proven stenosis ≥50% on angiography, surgical or percutaneous coronary or carotid revascularization or peripheral artery disease defined as claudication and vessel obstruction ≥50% at angiography or doppler ultrasound. Incident events were defined similarly to the latter in addition to cardiovascular deaths. All events and data were extracted from patient electronic medical records and confirmed by two of the authors (ERC and MHM).
      The study protocol conforms to the ethical guidelines of the 1975 Declaration of Helsinki, this study was approved by CAPPesq from HCFMUSP (project # 3757/12/013) and an informed consent was signed by all participants.

      2.1 Statistical analysis

      We considered that follow-up started at the inclusion in the program and ended at the last visit at lipid clinic. Initially participants were divided in those who presented or not first incident ASCVD events. To test the possible association of previous ASCVD and presence of a FH causing variant on incident events, participants were further divided into 4 groups (2 × 2) according to the presence (variant +) or absence of a genetic variant (variant-) and previous or not ASCVD (ASCVD+ and ASCVD-). Continuous variables were described as median (interquartile ranges 25% and 75%) and categorical variables as frequencies (%). Differences between groups were analyzed using the Kruskal Wallis or chi-square test, respectively. Normal distribution was tested by the Shapiro-Wilk or Kolmogorov Smirnov test.
      Kaplan-Meier survival curves were built to compare the overall ASCVD-free survival and the 4 groups were compared using the log-rank test. Annualized event rates were calculated for the whole population and for each group separately. Association of variables with first incident ASCVD events during follow-up was performed using univariate and multivariate Cox regression models and the hazard ratios (HR) and confidence intervals (95% CI) were calculated. For all tests, a p-value (2 sided) < 0.05 was considered statistically significant. Statistical analyses were made with SPSS (version 22) and Stata (version 14.2).

      3. Results

      From 4,111 individuals included in the cascade screening program, 938 (22.8%) were ≥60 years. We excluded respectively 26 (2.8%) and 450 (10.9%) since they either presented a variant of uncertain significance (VUS) or were not registered at the lipid clinic. From 462, 85 were also excluded since they were not followed for at least 6 months. The final study sample consisted of 377/4,111 (9.1%) old hypercholesterolemic individuals, 161 (42.7%) with genetic variants. Supplementary Fig. 1 shows patient study flow chart.
      During a median 4.8 (3.0; 7.3) years follow-up, 47 individuals suffered first incidental events (12.4%) with a 2.7% patient per-year rate (95% CI 2.0%; 3.5%). Coronary heart disease was the most frequent event. Of interest 10/47 patients had more than one event during follow up (Supplementary Table 1).
      Table 1 shows clinical and laboratory characteristics of subjects who presented or not an incident ASCVD during follow up. Supplementary Tables 2 and 3 show clinical and laboratory characteristics of participants divided by presence or not of genetic variants or previous ASCVD. Groups were similar regarding age, age >80 years, frequency of hypertension, current use of statins, use of high-intensity and duration of LLT, BMI, as well as TC and LDL-C values at the last follow-up visit. No differences were seen at baseline on the use of use of aspirin, clopidogrel, ACE inhibitors, ARB and beta blockers. As expected during follow-up there was a higher frequency of aspirin use in those who had incident ASCVD events. Patients with previous ASCVD at baseline had higher frequencies of male sex, current and previous smoking, and lower baseline HDL-C values (all p-values <0.05).
      Table 1Clinical and laboratory characteristics of old hypercholesterolemic individuals presenting or not occurrence of ASCVD events during follow-up.
      VariableWith new ASCVD onset (n = 47)Without new ASCVD onset (n = 330)p value
      Age (years)65 (62; 70)66 (63; 71)0.551
      Age ≥80 years0 (0%)20 (6.1%)0.065
      Male sex22 (46.8%)87 (26.3%)0.004
      Presence of genetic variant31 (66.0%)130 (39.4%)0.001
      Index cases24 (51.1%)247 (74.8%)0.001
      Hypertension37 (78.7%)223 (67.8%)0.129
      Diabetes mellitus20 (42.6%)79 (24.1%)0.007
      Current or previous smoker22 (46.8%)124 (37.6%)0.177
      Current smoker7 (14.8%)23 (7.0%)0.058
      Familial history of early ASCVD32 (68.1%)180 (54.5%)0.065
      Previous ASCVD29 (61.7%)92 (27.9%)0.000
      Previous early ASCVD15 (31.9%)45 (13.6%)0.001
      Age of first ASCVD onset (years)56 (49; 65.5)57 (50; 63)0.756
      DLCN
      DLCN (Dutch Lipid Clinics Network) score excluding corneal/senile arcus and genetic variants; to convert cholesterol to mmol/L multiply by 0.02586; to convert triglycerides mg/dL to mmol/L multiply by 0.01129.
      6 (4.5; 8.5)5 (4; 7)0.101
      Current statin use39 (83.0%)282 (85.4%)0.514
      High potency LLT30 (63.8%)197 (59.7%)0.518
      Duration of LLT (years)10 (5.5; 20)9 (4.5; 15)0.170
      Age of starting LLT (years)54 (49; 63)58 (50.5; 62)0.192
      Aspirin baseline27 (57.4%)146 (44.4%)0.093
      Aspirin follow-up42 (89.4%)157 (47.6%)0.000
      Clopidogrel baseline2 (4.3%)7 (2.1%)0.315
      Clopidogrel follow-up4 (8.5%)9 (2.7%)0.066
      Beta blockers baseline17 (36.2%)119 (36.1%)0.988
      Beta blockers follow-up32 (68.1%)133 (40.3%)0.000
      ACE baseline13 (27.7%)87 (26.4%)0.851
      ACE follow-up21 (44.7%)113 (34.2%)0.162
      ARB baseline11 (23.4%)58 (17.6%)0.334
      ARB follow-up14 (29.8%)89 (27.0%)0.685
      BMI (kg/m2)26.5 (24.4; 30.4)26.6 (24; 30.5)0.881
      Xanthomas8 (17.0%)43 (13.0%)0.464
      Corneal arcus13 (27.6%)76 (23.0%)0.492
      TC baseline (mg/dL)270 (205; 313)261 (195; 315)0.622
      TC follow up (mg/dL)234 (208; 288)216 (183; 279)0.126
      HDL-C baseline (mg/dL)46 (38; 52)50 (42; 59)0.012
      HDL-C follow up49 (39; 58)52 (44; 63)0.145
      LDL-C baseline (mg/dL)201 (142; 240)179 (120; 230)0.171
      LDL-C follow up148 (121; 192)142 (108; 202)0.238
      TG baseline (mg/dL)124 (85; 174)132 (91; 188)0.902
      TG follow up130 (88; 201)124 (86; 159)0.581
      Glucose (mg/dL)110 (96; 148)104 (96; 116)0.161
      Continuous data expressed as medians (%25; %75). ACE- angiotensin converting enzyme inhibitors; ARB- angiotensin receptor blockers; ASCVD- atherosclerotic cardiovascular disease; BMI- body mass index; LLT- lipid lowering therapy; TC- total cholesterol; TG- triglycerides.
      a DLCN (Dutch Lipid Clinics Network) score excluding corneal/senile arcus and genetic variants; to convert cholesterol to mmol/L multiply by 0.02586; to convert triglycerides mg/dL to mmol/L multiply by 0.01129.
      Table 2 shows Cox univariate association with incident ASCVD during follow-up. Male sex (p = 0.002), presence of a genetic variant (p = 0.008), diabetes mellitus (p = 0.011), current smoking (p = 0.024), previous (p = 0.000) and early ASCVD events (p = 0.004) were positively associated with incident events. Incidence of ASCVD was not associated with LLT, current or previous lipid profile except for an inverse association with HDL-C at baseline. No association was encountered between use of ASCVD modifying drugs at baseline with incident events. Individuals considered as index cases in the genetic cascade were less likely to develop ASCVD at follow-up (p = 0.003).
      Table 2Cox univariate associations with incident ASCVD events (n = 47) in 377 old individuals with hypercholesterolemia.
      VariableHR95% CIp value
      Age (years)0.9860.938–1.0360.573
      Age≥ 80 years0.0460.000–14.4620.294
      Male sex2.5331.427–4.4980.002
      Variant+2.2801.243–4.1800.008
      Index cases0.4150.234–0.7360.003
      Hypertension1.6530.822–3.3250.159
      Diabetes2.1221.190–3.7840.011
      Current + former smoker1.6580.921–2.9830.092
      Current smoker2.5451.131–5.7280.024
      Family history of early ASCVD1.7490.918–3.3320.089
      Previous ASCVD4.1142.283–7.4150.000
      Variant-/ASCVD-ReferenceReference
      Variant+/ASCVD-2.9511.105–7.8800.031
      Variant-/ASCVD+6.4702.346–17.8430.000
      Variant+/ASCVD+7.8733.149–19.7700.000
      Early ASCVD event2.4841.336–4.6190.004
      Age of first ASCVD event (years)0.9980.960–1.0380.937
      DLCN score
      DLCN score excluding corneal/senile arcus and genetic variants. To convert cholesterol to mmol/L multiply by 0.02586; to convert triglycerides mg/dL to mmol/L multiply by 0.01129.
      1.0510.917–1.2050.475
      Baseline statin use1.0610.257–4.3830.935
      High intensity LLT0.9380.510–1.7230.836
      LLT duration (years)1.0170.985–1.0500.304
      Age statin started (years)0.9800.924–1.0400.509
      Aspirin baseline1.5970.896–2.8490.113
      Clopidogrel baseline1.6390.397–6.7730.495
      Beta blockers baseline1.0650.587–1.9320.836
      ACE baseline1.0140.535–1.9230.966
      ARB baseline1.5400.783–3.0290.211
      BMI (kg/m2)0.9990.941–1.0600.974
      Xanthomas1.2110.565–2.5950.623
      Corneal/senile arcus1.0570.557–2.0060.865
      Baseline TC (mg/dL)1.0020.998–1.0060.286
      Follow-up TC1.0041.000–1.0070.058
      Baseline HDL-C (mg/dL)0.9650.938–0.9930.013
      Follow-up HDL-C0.9770.953–1.0020.070
      Baseline LDL-C (mg/dL)1.0030.999–1.0060.132
      Follow-up LDL-C1.0030.999–1.0070.161
      Baseline TG (mg/dL)1.0010.997–1.0050.590
      Follow-up TG1.0010.998–1.0050.443
      ACE- angiotensin converting enzyme inhibitors; ARB- angiotensin receptor blockers; ASCVD- atherosclerotic cardiovascular disease; BMI- body mass index; LLT- lipid lowering therapy; lipids in mg/dL; TC- total cholesterol; TG-triglycerides.
      a DLCN score excluding corneal/senile arcus and genetic variants. To convert cholesterol to mmol/L multiply by 0.02586; to convert triglycerides mg/dL to mmol/L multiply by 0.01129.
      Fig. 1 shows Kaplan-Meier curves for events during follow-up, with statistically significant differences between the 4 groups (p log-rank test <0.001). Groups with previous ASCVD events or genetic variants had lower event free survival than the groups without previous ASCVD or in which variants were not found. The annualized event rates were 0.8% (95% CI 0.36%; 1.70%), 2.3% (95% CI 1.3%; 4.1%), 5.2% (95% CI 2.8%; 9.7%) and 6.3% (95% CI 4.0%; 10.0%) respectively for groups variant-/ASCVD-, variant+/ASCVD-, variant-/ASCVD+ and, variant+/ASCVD+.
      Fig. 1
      Fig. 1Kaplan Meier curves for cardiovascular events during follow up.
      ASCVD- atherosclerotic cardiovascular disease.
      Fig. 2 shows the multivariate Cox adjusted risk of incident ASCVD in the groups according to the presence or absence of a genetic variant and/or previous ASCVD. Considering the variant-/ASCVD-group as a reference, those with variant-/ASCVD+ and variant+/ASCVD + had greater HR for incident events 6.45 and 5.05 respectively, however no significant difference was seen for those with variant+/ASCVD-. No interaction was found between previous ASCVD and presence of FH variants in prediction of incident ASCVD (p = 0.267). After multivariate analysis only the presence of previous ASCVD remained independently associated with incident ASCVD with a HR of 3.236 (95%CI 1.497–6.993, p = 0.003).
      Fig. 2
      Fig. 2Adjusted hazard ratios (95% confidence intervals) for incident cardiovascular events according to presence of FH genetic variants and previous ASCVD.
      Models adjusted for sex, HDL-C, diabetes mellitus and current smoking; ASCVD- atherosclerotic cardiovascular disease.

      4. Discussion

      Severe hypercholesterolemia causes an elevated risk of ASCVD especially CHD. A genetic diagnosis of FH implicates in higher burden of subclinical atherosclerosis [
      • Sharifi M.
      • Higginson E.
      • Bos S.
      • et al.
      Greater preclinical atherosclerosis in treated monogenic familial hypercholesterolemia vs. polygenic hypercholesterolemia.
      ] as well clinical ASCVD than in individuals with polygenic hypercholesterolemia or in those in whom genetic variants are not encountered [
      • Khera A.V.
      • Won H.H.
      • Peloso G.M.
      • et al.
      Diagnostic yield and clinical utility of sequencing familial hypercholesterolemia genes in patients with severe hypercholesterolemia.
      ,
      • Trinder M.
      • Francis G.A.
      • Brunham L.R.
      Association of monogenic vs polygenic hypercholesterolemia with risk of atherosclerotic cardiovascular disease.
      ]. However, availability of LLT may change this natural history. The main result of this study performed in old individuals with severe hypercholesterolemia, undergoing roughly 14 years of LLT, was that previous ASCVD events were independent markers of event occurrence while presence of FH genetic variants was not.
      Even though FH increases both relative and absolute CHD risk in comparison with the general population, this risk is much higher in people younger than 40 years [
      • Mundal L.J.
      • Igland J.
      • Veierod M.B.
      • et al.
      Impact of age on excess risk of coronary heart disease in patients with familial hypercholesterolaemia.
      ,
      • Neil A.
      • Cooper J.
      • Betteridge J.
      • et al.
      Reductions in all-cause, cancer, and coronary mortality in statin-treated patients with heterozygous familial hypercholesterolaemia: a prospective registry study.
      ]. Mundal et al. observed that in Norwegian patients with molecularly proven FH, 90% undergoing LLT, standardized incidence rates (95% CI) for myocardial infarction were reduced from 7.5 (3.7–14.9) in men and 13.6 (5.1–36.2) in women aged 25–39 years to 0.9 (0.4–2.1) in men and 1.8 (0.9–3.7) in women aged 70–79 years. Neil et al. found that after a 26-year follow-up of FH patients, mostly diagnosed by clinical Simon Broome criteria, standardized CHD mortality rates were no longer significant after the age of 40 for primary prevention FH individuals [
      • Neil A.
      • Cooper J.
      • Betteridge J.
      • et al.
      Reductions in all-cause, cancer, and coronary mortality in statin-treated patients with heterozygous familial hypercholesterolaemia: a prospective registry study.
      ]. Indeed, LLT overall was associated with a 48% reduction of excess mortality from 2-fold to none in all age strata. However, despite a 25% relative reduction in excess risk in those at secondary prevention this was still greater than the one seen in the general population even in older age strata.
      Findings of the current study suggest that this may indeed be the case and LLT may favorably change natural history of ASCVD in old people with severe hypercholesterolemia with lower benefits for those at secondary prevention. Previously on this cohort, Coutinho et al. observed that presence of FH causing variants was associated with 1.77 (95% CI:1.05 to 2.98) odds of prior manifestation of ASCVD in old individuals with hypercholesterolemia in comparison with genetically negative counterparts [
      • Coutinho E.R.
      • Miname M.H.
      • Rocha V.Z.
      • et al.
      Familial hypercholesterolemia and cardiovascular disease in older individuals.
      ]. However, this was apparently no longer the case when patients were additionally followed for a median of 4.8 years at the lipid clinic. In this study previous ASCVD was the sole independent factor associated with incident events and no formal statistical interaction was found with presence of FH causing variants.
      Our results do not weaken at any rate the importance of a monogenic defect in the pathophysiology of early ASCVD in people with severe hypercholesterolemia. Indeed, multiple studies have demonstrated the prognostic implication of an FH monogenic defect among hypercholesterolemic individuals, even after adjustment for LDL-C cholesterol levels [
      • Khera A.V.
      • Won H.H.
      • Peloso G.M.
      • et al.
      Diagnostic yield and clinical utility of sequencing familial hypercholesterolemia genes in patients with severe hypercholesterolemia.
      ,
      • Trinder M.
      • Francis G.A.
      • Brunham L.R.
      Association of monogenic vs polygenic hypercholesterolemia with risk of atherosclerotic cardiovascular disease.
      ]. However, our study suggests that as individuals with FH survive and get older, the relevance of an FH causing variant as a predictor for future events seems to decline. One reason may be due to survival bias, according to which, the FH individuals with the highest risk already presented fatal events, and those who were able to survive and reach an old age, particularly those without a premature ASCVD, are in the opposite extreme of the risk spectrum. Moreover, the old subjects included in this cohort have been on LLT for almost 14 years, and thus have been exposed to a long treatment, despite the overall late treatment onset in this age group (median of 58 years of age among those not presenting an incident event). Another reason may be the age itself which represents one of the most important risk factors for ASCVD as it advances and may attenuate the relative strength of other factors.
      Distinctly from the presence of an FH variant, previous history of ASCVD persisted as a strong predictor of incident events among the elderly. Therefore, once established, the presence of obstructive atherosclerotic disease, regardless of the vascular bed involved, represents a major risk factor for future events. This result reinforces the need for intensive LDL-C lowering therapy not only with monoclonal antibodies against PCSK9 inhibitors, but also the small interference RNA molecule inclisiran [
      • Scicchitano P.
      • Milo M.
      • Mallamaci R.
      • et al.
      Inclisiran in lipid management: a Literature overview and future perspectives.
      ] or bempedodic acid [
      • Goldberg A.C.
      • Leiter L.A.
      • Stroes E.S.G.
      • et al.
      Effect of bempedoic acid vs Placebo added to maximally tolerated statins on low-density lipoprotein cholesterol in patients at high risk for cardiovascular disease: the CLEAR wisdom randomized clinical trial.
      ] in addition to standard LLT not only for FH as has been suggested [
      • Santos R.D.
      • Gidding S.S.
      • Hegele R.A.
      • et al.
      Defining severe familial hypercholesterolaemia and the implications for clinical management: a consensus statement from the International Atherosclerosis Society Severe Familial Hypercholesterolemia Panel.
      ] but for all with severe hypercholesterolemia and previous ASCVD. Indeed, with these newer therapies further LDL-C lowering can be achieved [
      • Santos R.D.
      • Stein E.A.
      • Hovingh G.K.
      • et al.
      Long-term evolocumab in patients with familial hypercholesterolemia.
      ], and it would be possible to attain the more restrict goals proposed for very-high risk patients even for those with FH [
      • Mach F.
      • Baigent C.
      • Catapano A.L.
      • et al.
      ESC/EAS Guidelines for the management of dyslipidaemias: lipid modification to reduce cardiovascular risk.
      ].
      The strengths of this study include the well selected population of old people with severe hypercholesterolemia prospectively followed at a specialized lipid clinic, the use of state-of-the-art molecular diagnosis, the almost 14-year LLT duration and adjudication of all ASCVD events. However, its main limitations include data of patients participating on a genetic cascade screening program that may bring bias for a higher risk population, absence of data on severity of atherosclerotic plaque burden or extension of previous revascularization procedures and absence of Lp(a) values that have been previously shown to be associated with ASCVD in old people with FH [
      • Perez de Isla L.
      • Watts G.F.
      • Muniz-Grijalvo O.
      • et al.
      A resilient type of familial hypercholesterolaemia: case-control follow-up of genetically characterized older patients in the SAFEHEART cohort.
      ]. Furthermore, we may quote the relative limited number of events although the annualized event rates are quite like the ones found in the larger and contemporary SAFEHEART study [
      • Perez de Isla L.
      • Alonso R.
      • Mata N.
      • et al.
      Predicting cardiovascular events in familial hypercholesterolemia: the SAFEHEART registry (Spanish familial hypercholesterolemia cohort study).
      ]. Finally, despite additional LDL-C lowering after admission to the lipid clinic residual LDL-C is still elevated according to current recommendations [
      • Mach F.
      • Baigent C.
      • Catapano A.L.
      • et al.
      ESC/EAS Guidelines for the management of dyslipidaemias: lipid modification to reduce cardiovascular risk.
      ].
      In conclusion, in old severe hypercholesterolemic individuals participating on a genetic cascade screening FH program undergoing long-term LLT previous ASCVD was associated with incident events while FH causing variants were not.

      Financial support

      RDS is recipient of a scholarship from Conselho Nacional de Pesquisa e Desenvolvimento Tecnológico, Brazil, (CNPq) #303734/2018-3. The funding of Sociedade Hospital Samaritano and Ministério da Saúde (PROADI-SUS; SIPAR: 25000.180.672/2011-81) and FAPESP (grant no 2013/17368-0) are gratefully acknowledged.

      CRediT authorship contribution statement

      Elaine R. Coutinho: data collection, Formal analysis, Writing – original draft. Marcio H. Miname: Formal analysis, Writing – original draft. Viviane Z. Rocha: Writing – original draft. Marcio S. Bittencourt: Formal analysis. Cinthia E. Jannes: data collection. Jose E. Krieger: data collection, study design, Funding acquisition, Supervision. Alexandre C. Pereira: study design. Raul D. Santos: study design, Supervision, Writing – original draft.

      Declaration of competing interest

      ERC has received honoraria related to speaker activities from Amgen, Ache and Novartis; MHM has received honoraria related to speaker activities from Amgen; VZR has received honoraria related to speaker activities from: Ache, Amgen, Novo-Nordisk and Sanofi; MSB has received honoraria from Boston Scientific and Novo-Nordisk; RDS has received honoraria related to consulting, research and/or speaker activities from: Abbott, Ache, Amgen, Amryt, Astra Zeneca, Biolab, Esperion, Getz Pharma, Kowa, Libbs, Novo-Nordisk, Novartis, Merck, Pfizer, PTC Therapeutics and Sanofi; all other authors have none to declare.

      Appendix A. Supplementary data

      The following is the supplementary data to this article:

      References

        • Mach F.
        • Baigent C.
        • Catapano A.L.
        • et al.
        ESC/EAS Guidelines for the management of dyslipidaemias: lipid modification to reduce cardiovascular risk.
        Eur. Heart J. 2020; 41 (2019): 111-188
        • Hu P.
        • Dharmayat K.I.
        • Stevens C.A.T.
        • et al.
        Prevalence of familial hypercholesterolemia among the general population and patients with atherosclerotic cardiovascular disease: a systematic review and meta-analysis.
        Circulation. 2020; 141: 1742-1759
        • Beheshti S.O.
        • Madsen C.M.
        • Varbo A.
        • et al.
        Worldwide prevalence of familial hypercholesterolemia: meta-analyses of 11 Million subjects.
        J. Am. Coll. Cardiol. 2020; 75: 2553-2566
        • Defesche J.C.
        • Gidding S.S.
        • Harada-Shiba M.
        • et al.
        Familial hypercholesterolaemia.
        Nat. Rev. Dis. Prim. 2017; 317093
      1. Mortality in Treated Heterozygous Familial Hypercholesterolaemia: Implications for Clinical Management. Scientific Steering Committee on Behalf of the Simon Broome Register Group.
        Atherosclerosis. 1999; 142: 105-112
        • Khera A.V.
        • Won H.H.
        • Peloso G.M.
        • et al.
        Diagnostic yield and clinical utility of sequencing familial hypercholesterolemia genes in patients with severe hypercholesterolemia.
        J. Am. Coll. Cardiol. 2016; 67: 2578-2589
        • Mata P.
        • Alonso R.
        • Perez-Jimenez F.
        Screening for familial hypercholesterolemia: a model for preventive medicine.
        Rev. Esp. Cardiol. 2014; 67: 685-688
        • Miname M.H.
        • Santos R.D.
        Reducing cardiovascular risk in patients with familial hypercholesterolemia: risk prediction and lipid management.
        Prog. Cardiovasc. Dis. 2019; 62: 414-422
        • Lacaze P.
        • Sebra R.
        • Riaz M.
        • et al.
        Familial hypercholesterolemia in a healthy elderly population.
        Circ Genom Precis Med. 2020; 13e002938
        • Mata N.
        • Alonso R.
        • Badimon L.
        • et al.
        Clinical characteristics and evaluation of LDL-cholesterol treatment of the Spanish familial hypercholesterolemia longitudinal cohort study (SAFEHEART).
        Lipids Health Dis. 2011; 10: 94
        • Versmissen J.
        • Oosterveer D.M.
        • Yazdanpanah M.
        • et al.
        Efficacy of statins in familial hypercholesterolaemia: a long term cohort study.
        BMJ (Clinical research ed.). 2008; 337: a2423
        • Santos R.D.
        • Coutinho E.R.
        Resilience of individuals with familial hypercholesterolaemia to develop atherosclerotic cardiovascular disease: lessons learned from the elderly.
        Eur. J. Prev. Cardiol. 2021;
        • Mundal L.J.
        • Igland J.
        • Veierod M.B.
        • et al.
        Impact of age on excess risk of coronary heart disease in patients with familial hypercholesterolaemia.
        Heart. 2018; 104: 1600-1607
        • Neil A.
        • Cooper J.
        • Betteridge J.
        • et al.
        Reductions in all-cause, cancer, and coronary mortality in statin-treated patients with heterozygous familial hypercholesterolaemia: a prospective registry study.
        Eur. Heart J. 2008; 29: 2625-2633
        • Lloyd-Jones D.M.
        • Leip E.P.
        • Larson M.G.
        • et al.
        Prediction of lifetime risk for cardiovascular disease by risk factor burden at 50 years of age.
        Circulation. 2006; 113: 791-798
        • Jansen A.C.
        • van Aalst-Cohen E.S.
        • Tanck M.W.
        • et al.
        The contribution of classical risk factors to cardiovascular disease in familial hypercholesterolaemia: data in 2400 patients.
        J. Intern. Med. 2004; 256: 482-490
        • Coutinho E.R.
        • Miname M.H.
        • Rocha V.Z.
        • et al.
        Familial hypercholesterolemia and cardiovascular disease in older individuals.
        Atherosclerosis. 2021; 318: 32-37
        • Perez de Isla L.
        • Watts G.F.
        • Muniz-Grijalvo O.
        • et al.
        A resilient type of familial hypercholesterolaemia: case-control follow-up of genetically characterized older patients in the SAFEHEART cohort.
        Eur. J. Prev. Cardiol. 2022; 29: 795-801
        • Shetty P.
        • matter Grey
        Ageing in developing countries.
        Lancet. 2012; 379: 1285-1287
        • Jannes C.E.
        • Santos R.D.
        • de Souza Silva P.R.
        • et al.
        Familial hypercholesterolemia in Brazil: cascade screening program, clinical and genetic aspects.
        Atherosclerosis. 2015; 238: 101-107
        • Silva P.R.S.
        • Jannes C.E.
        • Oliveira T.G.M.
        • et al.
        Evaluation of clinical and laboratory parameters used in the identification of index cases for genetic screening of familial hypercholesterolemia in Brazil.
        Atherosclerosis. 2017; 263: 257-262
        • Richards S.
        • Aziz N.
        • Bale S.
        • et al.
        Standards and guidelines for the interpretation of sequence variants: a joint consensus recommendation of the American College of medical genetics and Genomics and the association for molecular pathology.
        Genet. Med. 2015; 17: 405-424
        • Sharifi M.
        • Higginson E.
        • Bos S.
        • et al.
        Greater preclinical atherosclerosis in treated monogenic familial hypercholesterolemia vs. polygenic hypercholesterolemia.
        Atherosclerosis. 2017; 263: 405-411
        • Trinder M.
        • Francis G.A.
        • Brunham L.R.
        Association of monogenic vs polygenic hypercholesterolemia with risk of atherosclerotic cardiovascular disease.
        JAMA Cardiol. 2020; 5: 390-399
        • Scicchitano P.
        • Milo M.
        • Mallamaci R.
        • et al.
        Inclisiran in lipid management: a Literature overview and future perspectives.
        Biomed. Pharmacother. 2021; 143112227
        • Goldberg A.C.
        • Leiter L.A.
        • Stroes E.S.G.
        • et al.
        Effect of bempedoic acid vs Placebo added to maximally tolerated statins on low-density lipoprotein cholesterol in patients at high risk for cardiovascular disease: the CLEAR wisdom randomized clinical trial.
        JAMA. 2019; 322: 1780-1788
        • Santos R.D.
        • Gidding S.S.
        • Hegele R.A.
        • et al.
        Defining severe familial hypercholesterolaemia and the implications for clinical management: a consensus statement from the International Atherosclerosis Society Severe Familial Hypercholesterolemia Panel.
        Lancet Diabetes Endocrinol. 2016; 4: 850-861
        • Santos R.D.
        • Stein E.A.
        • Hovingh G.K.
        • et al.
        Long-term evolocumab in patients with familial hypercholesterolemia.
        J. Am. Coll. Cardiol. 2020; 75: 565-574
        • Perez de Isla L.
        • Alonso R.
        • Mata N.
        • et al.
        Predicting cardiovascular events in familial hypercholesterolemia: the SAFEHEART registry (Spanish familial hypercholesterolemia cohort study).
        Circulation. 2017; 135: 2133-2144