The purpose of this study was to investigate the effect of periodontitis on development of overt nephropathy, defined as macroalbuminuria, and end-stage renal disease (ESRD) in type 2 diabetes.
RESEARCH DESIGN AND METHODS:
Individuals residing in the Gila River Indian Community aged > or =25 years with type 2 diabetes, one or more periodontal examination, estimated glomerular filtration rate > or =60 ml/min per 1.73 m(2), and no macroalbuminuria (urinary albumin-to-creatinine ratio > or =300 mg/g) were identified. Periodontitis was classified as none/mild, moderate, severe, or edentulous using number of teeth and alveolar bone score. Subjects were followed to development of macroalbuminuria or ESRD, defined as onset of renal replacement therapy or death attributed to diabetic nephropathy.
Of the 529 individuals, 107 (20%) had none/mild periodontitis, 200 (38%) had moderate periodontitis, 117 (22%) had severe periodontitis, and 105 (20%) were edentulous at baseline. During follow-up of up to 22 years, 193 individuals developed macroalbuminuria and 68 developed ESRD. Age- and sex-adjusted incidence of macroalbuminuria and ESRD increased with severity of periodontitis. After adjustment for age, sex, diabetes duration, BMI, and smoking in a proportional hazards model, the incidences of macroalbuminuria were 2.0, 2.1, and 2.6 times as high in individuals with moderate or severe periodontitis or those who were edentulous, respectively, compared with those with none/mild periodontitis (P = 0.01). Incidences of ESRD in individuals with moderate or severe periodontitis or in those who were edentulous were 2.3, 3.5, and 4.9 times as high, respectively, compared with those with none/mild periodontitis (P = 0.02).
Periodontitis predicts development of overt nephropathy and ESRD in individuals with type 2 diabetes. Whether treatment of periodontitis will reduce the risk of diabetic kidney disease remains to be determined.