Clinical and biochemical characteristics of acromegalic patients with different abnormalities in glucose metabolism.

To determine the prevalence of diabetes, glucose intolerance and impaired fasting glucose in Mexican patients with acromegaly and establish associations with clinical, anthropometric and biochemical variables. 257 patients with acromegaly were evaluated by a 75 g-oral glucose tolerance test with measurements of both GH and glucose (0, 30, 60, 90 120 min) as well as baseline IGF-1. Normal glucose tolerance (NGT), impaired fasting glucose (IFG), impaired glucose tolerance (IGT) and diabetes (DM) were defined based on the 2003 ADA criteria. NGT, IFG, IGT and DM were found in 27.6, 8.9, 31.6 and 31.9% of the subjects, respectively; 42 of the DM patients were unaware of the diagnosis. Patients with diabetes were older than subjects in the other 3 categories (P = 0.001), and the proportion of women was significantly higher in the DM (74%) and IGT (68%) groups than in the NGT group (52%) (P = 0.004). Odds ratio for the development of DM was 3.29 (95% CI 3.28-3.3). GH and IGF-1 levels were comparable among the different groups. In a multivariable analysis DM was significantly associated with age, presence of a macroadenoma, disease duration and a basal GH > 30 μg/dl. DM and probably IGT are more prevalent in acromegaly than in the general Mexican population. DM was more frequent in females of all ages, in subjects with severely elevated GH concentrations, in patients with macroadenomas, and long-standing disease duration. The odds ratio for DM in our subjects with acromegaly is more than 3 times higher than in the general population.