Factors predicting the age when type 2 diabetes is diagnosed in Hong Kong Chinese subjects

OBJECTIVE To examine the factors predicting age at diagnosis of type 2 diab etes in Hong Kong Chinese. RESEARCH DESIGN AND METHODS The relationships between age at diagnosis and parental history of diabetes as well as an array of clinical and metabolic factors were examined using a hospital clinic-based diabetes registry invol ving 3,414 index patients with type 2 diabetes. Patterns of age at diagnosi s in successive generations were also examined using 21 affected child-pare nt pairs and 7 affected child-parent-grandparent trios. RESULTS Approximately 29% of the index patients were diagnosed with type 2 diabetes at less than or equal to 35 years of age (hereby defined as early- onset). The early-onset patients had higher rates of positive paternal (16 vs. 5%) and maternal (22 vs. 12%) history of diabetes (boty at P < 0.01) an d had poorer metabolic profiles. In the overall index patients, male sex, h igher HbA waist-to-hip ration (WHR), and systolic blood pressure (sBP); low er HDL cholesterol level; and a positive paternal as well as maternal histo ry of diabetes predicted younger age at diagnosis. More senior age and high er BMI and diastolic blood pressure predicted older age at diagnosis. Predi ctors for younger age at diagnosis in the male patients were higher HbA and sBP and a positive paternal history of diabetes. Predictors for younger ag e at diagnosis in the female patients were higher HbA(1c). Whr and sBp and a paternal as well as maternal history of diabetes. In the affected child-p arent pairs and child-parent-grandparent trios, there was a decrease in age at diagnosis in successive generations. CONCLUSIONS Our data indicate that both familial (possibly genetic) and met abolic lactors affect the age of onset of type 2 in the Chinese population. The result also suggest an onset and progression pattern of the disease th at is compatible with the phenomenon of anticipation.