Biochemical features of eugonadal patients with idiopathic gynaecomastia: A retrospective cross-sectional study

Patients with idiopathic gynaecomastia have greater BMI and an unfavourable lipid profile compared with age-matched controls. Twenty-five adult eugonadal patients with idiopathic gynaecomastia and 50 age- and BMI-matched controls were selected. Clinical and biochemical parameters and ultrasound testis volume were reviewed retrospectively. Patients and controls differed for no biochemical parameter, except for LH levels, which were 31% higher in patients (p = 0.019), although within the normal range. Compared with controls, patients had a threefold greater rate of elevated LDL-c (p = 0.025). Patients ≥ 25 years had higher levels of serum LDL-c compared with either patients < 25 years (p = 0.006) or controls ≥ 25 years (p = 0.012). In patients, both at bivariate analysis and at linear regression, age correlated positively with total cholesterol and LDL-c, the latter correlated inversely with total testosterone. Negative interactions were found for age and total testosterone with LDL-c, for LH and estradiol to testosterone ratio (E2:T) with LDL-c, and for age and E2:T with total cholesterol. Our data suggest inadequate local androgen action in patients with idiopathic gynaecomastia. This partial androgen resistance might blunt the beneficial effects of testosterone on lipid metabolism. Further studies are needed to verify whether this metabolic derangement impacts the cardiovascular health of these patients.