Aim: The present study was designed to estimate the progression rates from combination of normal weight, overweight, obesity, and number of metabolic abnormalities (MA) to type 2 diabetes (T2D) in a non-diabetic high risk population in Isfahan, Iran.

Methods: A total of 1869 non-diabetic first-degree relatives (FDR) of patients with T2D 30-70 years old were examined and followed for a mean (SD) of 7.3 (2.2) years for T2D incidence. At baseline and through follow-up, participants underwent a standard 75-g 2-h oral glucose tolerance test.

Results: The metabolically healthy overweight and obese at baseline were associated with incidence of T2D, independently of age and gender. Any one MA increased the risk of developing T2D among normal weight, overweight and obese individuals. Those with normal weight and ≥3 MA were over 20 times (odds ratios (OR) 20.21; 95% confidence intervals (CI) 2.4, 170.4) and those with overweight and ≥3 MA 22.5 times (OR 22.5; 95% CI 3.0, 167.0) and obese with ≥3 MA were 25.4 times (OR 25.4; 95% CI 3.4, 187) more likely to develop T2D than those with normal weight and without MA. Compared with participants without MA, obese individuals with concomitant MA were not significantly more likely to progress to T2D.

Conclusion: Our data provide further evidence that normal weight, overweight and obese individuals with MA had a higher risk of incident T2D than normal weight individuals without MA.