Objective: This study describes the clinical characteristics of childhood- and adolescent-onset type 2 diabetes mellitus (CAT2DM) seen at a diabetes center in southern India.
Research design and methods: Between January 1992 and December 2009, 368 CAT2DM patients were registered. Anthropometric measurements were done using standardized techniques. Biochemical investigations included C-peptide measurements and glutamic acid decarboxylase antibody assay wherever feasible. Retinopathy was diagnosed by retinal photography; microalbuminuria, if urinary albumin excretion was between 30 and 299 mg/μg of creatinine; nephropathy, if urinary albumin excretion was ≥300 mg/μg; and neuropathy, if vibration perception threshold on biothesiometry was ≥20 V.
Results: The proportion of CAT2DM patients, expressed as percentage of total patients registered at our center, rose from 0.01% in 1992 to 0.35% in 2009 (P<0.001). Among the 368 cases of CAT2DM, 96 (26%) were diagnosed before the age of 15 years. The mean age at first visit and age at diagnosis of the CAT2DM subjects were 22.2±9.7 and 16.1±2.5 years, respectively. Using World Health Organization growth reference charts, 56% of boys and 50.4% of girls were >85(th) percentile of body mass index for age. Prevalence rates of retinopathy, microalbuminuria, nephropathy, and neuropathy were 26.7%, 14.7%, 8.4%, and 14.2%, respectively. Regression analysis revealed female gender, body mass index >85(th) percentile, parental history of diabetes, serum cholesterol, and blood pressure to be associated with earlier age at onset of CAT2DM.
Conclusions: CAT2DM appears to be increasing in urban India, and the prevalence of microvascular complications is high. Female predominance is seen at younger ages.