Early Treatment, Lifelong Impact: Long-Term Cardiovascular Outcomes of Children With Familial Hypercholesterolemia

BACKGROUND: Current guidelines recommend initiating statin therapy in childhood for patients with familial hypercholesterolemia (FH) to reduce their cardiovascular risk. However, definitive evidence that early treatment leads to a reduction in cardiovascular events and mortality in adulthood is still lacking. This study aims to evaluate the incidence of cardiovascular events and cardiovascular death in adults with FH diagnosed and treated from childhood and compare these outcomes with those of their unaffected siblings and parents with FH for whom statins were not available in childhood. METHODS: For this cohort study, all individuals who attended the Amsterdam UMC pediatric lipid clinic as children for a tentative diagnosis of FH, and were aged ≥18 years as of January 1, 2024, were eligible. We combined existing clinical data obtained from local electronic medical records with newly collected information by means of an online questionnaire. RESULTS: Of the 526 adults included, 404 had FH, and 122 were unaffected siblings (mean [SD] age, 32.5 [7.2] and 33.1 [5.9] years, respectively). At age 52 years, the cumulative cardiovascular event–free proportion was similar in patients with FH treated from childhood and their unaffected siblings (0.98 [95% CI, 0.96–1.00] and 0.99 [95% CI, 0.97–1.00], respectively; HR adjusted-for-sex [95% CI], 0.94 [0.10–9.09]). The cumulative cardiovascular event–free proportion of their parents with FH was significantly lower (0.70 [95% CI, 0.54–0.74]; HR adjusted-for-sex [95% CI], 8.1 [2.5–25.7]). The cumulative cardiovascular death–free proportion was both 1.0 among patients with FH and their unaffected siblings, and 0.93 (95% CI, 0.90–0.95) among their affected parents ( P =0.009). CONCLUSIONS: Our findings show a significant disparity in cardiovascular risk between parents with FH, who were untreated during childhood, and their adult FH offspring, who received early statin treatment. Furthermore, the lack of difference in cardiovascular outcomes between adult patients with FH and their unaffected siblings further supports the long-term benefits of early FH diagnosis and subsequent lipid-lowering treatment.