Prevalence of diabetes mellitus in 6050 hypopituitary patients with adult-onset GH deficiency before GH replacement: a KIMS analysis.

OBJECTIVE: GH deficiency (GHD) in adults is characterized by a tendency toward obesity and an adverse body composition with visceral fat deposit and may thus predispose to the development of type 2 diabetes mellitus. The aim of this study was to assess the observed prevalence proportion (PP) and observed PP over expected PP ratio (standardized prevalence proportion ratio, SPR) of diabetes according to International Diabetes Federation criteria in a large cohort of GH-untreated adult-onset GHD patients. DESIGN AND METHODS: Associations between baseline variables and diabetes prevalence in 6050 GHD patients from KIMS (Pfizer International Metabolic Database) were studied and robust Poisson-regression analyses were performed. Comparisons between baseline status and HbA1c categories in the nondiabetic patients were done with covariance analysis. P values <0.05 were considered statistically significant.
RESULTS: PP was 9.3% compared with the expected 8.2%. SPR was 1.13 (95% confidence intervals (95% CIs), 1.04-1.23), which was significantly increased in females (1.23; 95% CI, 1.09-1.38%) but not in males (SPR 1.04; 95% CI, 0.92-1.17%). PP increased significantly by age, familial diabetes, country selection, BMI, waist circumference, number of pituitary deficiencies, and GHD etiology. SPR decreased significantly by age and increased significantly by BMI, waist circumference, and IGF1 SDS. Multiple regression model showed that the most important impact on SPR was from age and BMI. HbA1c values of 6.0-6.5% were found in 9.5% of nondiabetic patients and were associated with higher BMI and waist circumference.
CONCLUSIONS: GHD is associated with an increased prevalence of diabetes, largely to be explained by the adverse body composition. These data urge toward early initiation of lifestyle modification measures.