HDL Cholesterol and Atherogenic Lipid Indices in Hidradenitis Suppurativa: Associations with BMI and Hurley Disease Severity

Background: Hidradenitis suppurativa (HS) is a chronic inflammatory disease associated with cardiometabolic comorbidities and increased cardiovascular risk. Methods: This retrospective case–control study evaluated serum lipid parameters and atherogenic indices—including the atherogenic index of plasma (AIP), Castelli risk index I (CRI-I), Castelli risk index II (CRI-II), and the atherogenic coefficient (AC)—in 176 patients with HS compared with 132 controls frequency-matched for age and sex and examined their associations with BMI and Hurley stage using multiple linear regression models. Results: BMI was significantly higher in patients with HS than in controls (median 29.4 vs. 26.1 kg/m2, p < 0.001), and subsequent regression analyses were therefore adjusted for BMI. Patients with HS exhibited higher triglyceride, LDL-C, and non-HDL-C levels, lower HDL-C levels, and higher atherogenic indices than controls, whereas total cholesterol did not differ significantly between the groups. After BMI adjustment, differences in triglyceride, LDL-C, and non-HDL-C lost significance, whereas HDL-C and all atherogenic indices remained significantly altered. In ordinal trend analyses, increasing Hurley stage showed modest associations with lower HDL-C and higher LDL-C, non-HDL-C, CRI-I, CRI-II, and AC, whereas triglycerides and AIP showed no significant trends after FDR correction. Conclusion: However, residual confounding by unmeasured cardiometabolic and lifestyle factors cannot be excluded, and the present findings do not establish increased cardiovascular risk or the clinical predictive utility of these indices. These findings should therefore be considered hypothesis-generating and warrant confirmation in prospective studies incorporating comprehensive cardiometabolic covariates, inflammatory biomarkers, and direct measures of subclinical atherosclerosis.