Background: Epidemiological studies have associated androgenetic alopecia (AGA) with severe young-age coronary artery disease and hypertension, and linked it to insulin resistance. We carried out a case-control study in age- and weight-matched young males to study the link between AGA and insulin resistance using the homeostasis model assessment of insulin resistance (HOMA-IR) index or metabolic syndrome clinical manifestations.
Methods: Eighty young males, 18-35 years old, with AGA > or = stage III in the Hamilton-Norwood classification, and 80 weight- and age-matched controls were included. Alopecia, glucose, serum insulin, HOMA-IR index, lipid profile and androgen levels, as well as metabolic syndrome criteria, were evaluated.
Results: The HOMA-IR index was significantly higher in cases than controls. Nonobese cases had a higher mean diastolic blood pressure and a more frequent family history of AGA than nonobese controls. A borderline difference in the HOMA-IR index was found in obese AGA cases vs. obese controls [P = 0.055, 95% confidence interval (CI) 2.36-4.20 vs. 1.75-2.73]. Free testosterone values were significantly higher in controls than cases, regardless of body mass index (BMI). A statistically significant additive effect for obesity plus alopecia was found, with significant trends for insulin, the HOMA-IR index, lipids and free testosterone when BMI and alopecia status were used to classify the participants.
Conclusions: Our results support the recommendation for assessing insulin resistance and cardiovascular-related features and disorders in all young males with stage III or higher AGA, according to the Hamilton-Norwood classification.