Identification of familial hypercholesterolemia in a country-wide laboratory network in Sri Lanka.

Familial hypercholesterolemia (FH) is a common inherited condition resulting in elevated low-density lipoprotein cholesterol (LDL-C) and increased risk of premature coronary artery disease. Despite its clinical significance, FH remains underdiagnosed in South Asia. This study aims to determine the prevalence and demographic distribution of FH in Sri Lanka, using data from a country-wide laboratory network. The study is a cross-sectional and observational study. Retrospective collection of lipid panels from a laboratory network, covering October 2024-March 2025 was done. Patients with LDL-C >190 mg/dl were recruited for the study, and Make Early Diagnoses to Prevent Early Deaths criteria were used for FH diagnosis. Statistical analysis calculated the prevalence with 95% confidence interval (CI); subgroup analyses were done by age, sex, and district. A total of 219,653 individuals had done a lipid profile test, of which 13,592 individuals had an LDL-C >190 mg/dl. FH was prevalent in 0.57%, equivalent to a ratio of 1:177 (95% CI: 0.54-0.60), accounting for 1243 cases. Most cases were male (n = 703); highest prevalence in >40 age group (n = 524, 3.9%) and in the Western Province of the country (Colombo, Gampaha). Males <20 years had higher LDL-C than females, but females >40 had higher LDL-C. Males had higher triglycerides and lower HDL across ages. LDL/HDL and CHOL/HDL ratios were consistently higher in males. This study reveals that FH is more prevalent in Sri Lanka than previously recognized, with notable differences by age, sex, and geographic region. The findings highlight a significant burden of undiagnosed FH and emphasize the importance of implementing nationwide screening.