Lower Serum Creatinine Is a New Risk Factor of Type 2 Diabetes: The Kansai Healthcare Study

OBJECTIVE—Because skeletal muscle is one of the target tissues for insulin, skeletal muscle mass might be associated with type 2 diabetes. Serum creatinine is a possible surrogate marker of skeletal muscle mass. The purpose of this study was to determine whether serum creatinine level is associated with type 2 diabetes. RESEARCH DESIGN AND METHODS—The study participants were nondiabetic Japanese men (n = 8,570) aged 40–55 years at entry. Type 2 diabetes was diagnosed if fasting plasma glucose was ≥126 mg/dl or if participants were taking oral hypoglycemic medication or insulin. RESULTS—During the 4-year follow-up period, 877 men developed type 2 diabetes. Lower serum creatinine was associated with an increased risk of type 2 diabetes. The multiple-adjusted odds ratio for those who had serum creatinine levels between 0.40 and 0.60 mg/dl was 1.91 (95% CI 1.44–2.54) compared with those who had levels between 0.71 and 0.80 mg/dl. CONCLUSIONS—Lower serum creatinine increased the risk of type 2 diabetes.