BACKGROUND: An increased risk for periodontitis has been associated both with type-1 or insulin dependent diabetes (IDDM) and with type-2 or non-insulin dependent diabetes (NIDDM).

AIMS: 1) To describe and analyze periodontal conditions in older low-income ethnic diverse subjects with or without a diagnosis of diabetes. 2) To assess to what extent diabetes mellitus is associated with periodontal status, and 3) how periodontitis ranks as a coexisting disease among other diseases in subjects with diabetes mellitus.

MATERIAL AND METHODS: Radiographic signs of alveolar bone loss were studied in 1101 older subjects 60-75 years old (mean age 67.6, SD+/-4.7). The number of periodontal sites and the proportions of teeth with probing depth (PD) > or =5 mm, clinical attachment levels (CAL) > or =4 mm were studied in a subset of 701 of the subjects.

RESULTS: IDDM was reported by 2.9% and NIDDM by 9.2% of the subjects. The number of remaining teeth did not differ by diabetic status. The number of sites with PD > or =5 mm and the proportion of PD with > or =5 mm was significantly smaller in the non-diabetic group (chi2=46.8, p<0.01, and chi2=171.1, p<0.001, respectively). Statistical analysis failed to demonstrate group differences for the number and proportions of sites with CAL > or =4 mm and for radiographic findings of alveolar bone loss. Combining all periodontal parameters revealed that the Mantel-Haenszel common odds of having IDDM/NIDDM and periodontitis was 1.8 : 1 (95% CI: 1.1-3.1, p<0.03). The common odds ratio estimate of an association between heart disease and diabetes was 3.6 : 1 (95% CI: 2.1-2.6, p<0.001).

CONCLUSIONS: Probing depth differences between IDDM/NIDDM vs. non-diabetic subjects may reflect the presences of pseudo-pockets and not progressive periodontitis in many subjects with diabetes mellitus. Periodontitis is not a predominant coexisting disease in older subjects with diabetes mellitus.