Prevalence and risk factors of diabetes in patients with Klinefelter syndrome: a longitudinal observational study.

To evaluate the prevalence and risk factors of diabetes in patients with Klinefelter syndrome.Retrospective longitudinal study.Medical college hospital.Klinefelter group (n = 39) and idiopathic hypogonadotropic hypogonadism (IHH) group (n = 40).Testosterone replacement therapy.The metabolic parameters, lipid profiles, and sex hormones were compared before and after T replacement therapy. The median duration of follow-up was 4 years in the Klinefelter group and 5.2 years in the IHH group.The prevalence of diabetes was 20.5% (8 of 39) in the Klinefelter group and 5% in the IHH group. In the Klinefelter group, the incidence of diabetes was 12.5% in patients with 47,XXY karyotype and 57.1% in patients with other atypical karyotypes, such as 46XY/47XXY chimera. In the Klinefelter group, the average (± SD) age at diagnosis of diabetes was 27.1 ± 4.5 years. Four subjects had diabetes before T therapy, and their blood glucose did not improve after T replacement. One patient had a history of acute pancreatitis. Two other subjects had very high triglyceride levels. During the follow-up, body weight increased more in Klinefelter patients than in IHH patients.The prevalence of diabetes is higher in Klinefelter patients than in IHH patients, possibly owing to abnormal karyotypes. Other risk factors, such as low T level, high body weight, acute pancreatitis, and high triglyceride levels, may also contribute to the development of diabetes.