VA Dental Diabetes Study: Twelve month results

Objective: The relationship between periodontitis and diabetes is complex and persons with diabetes are more likely to have periodontal disease. A related question is whether periodontal therapy improves glycemic control among persons with poorly controlled diabetes. Here we report results of four-months versus twelve-months of structured periodontal treatment in a randomized clinical trial of the efficacy of periodontal care in the improvement of glycemic control in veterans with poorly controlled diabetes. Methods: We enrolled 162 veterans (mean age=59, mean number of teeth = 21) with poorly controlled diabetes defined as HbA1c >8.5% on at least 2 occasions. They were randomly assigned to four months or twelve months of therapy, including initial scaling and root planing plus doxycycline 100 mgm po * 14days and 0.12% chlorhexidine rinse * 4 months. Antimicrobials were not continued after the first 4 months in either group. Outcomes included the percent of participants with improvement in hemoglobin A1c (HbA1c) between pretreatment and 1-year post-treatment initiation in the FOUR MONTHS versus TWELVE MONTHS therapy groups. Analyses included simple/multiple variable logistic regressions, adjusted for baseline HbA1c, age over 55 years, and increasing insulin over the 12-month period.

Results: Unadjusted analyses of change after 12 months showed that the percent with HbA1c improvement was greater in the FOUR MONTHS OF THERAPY GROUP (52%) versus the TWELVE MONTHS OF THERAPY GROUP (35%), p=0.03. Odds of improvement in the TWELVE MONTH group were 0.36 (95%CI: 0.16,0.78) relative to the FOUR MONTH group, after adjusting for age>55, baseline HbA1c, and increases in insulin.

Conclusions: Veterans with poorly controlled diabetes who had periodontal therapy for only 4 months had a greater likelihood of improvement in HbA1c at 12 months after initiation of therapy compared to those treated for 12 months.

VA HSR&D QUERI DII-99.206 and NIH K24 DE00419 and NIH K24 DE018211