Prediabetes mellitus (PDM) risk is greater in individuals with abdominal obesity and smoking habit. Smoking affects β-cell activity and insulin sensitivity, while abdominal obesity is a major factor for insulin resistance. 

To evaluate the independent and interactive impact of smoking and abdominal obesity in the development of PDM, a recent cross-sectional study was conducted with 3,017 participants (40-79 years old) in southwest China. 

Out of the total population, 38.98% were diagnosed with PDM. The findings revealed that current smokers had 26% higher risk whereas individuals with abdominal obesity had a 40% higher risk of developing PDM. 

Individuals with both risk factors had a threefold higher likelihood of developing PDM than healthy individuals without either factor. 

The synergistic risk between current smoking and abdominal obesity was found to be 5.51 times greater than the sum of their individual effects in individuals exposed to only one of these factors.