Effect of being overweight and obese on periodontal treatment costs

Obesity can increase a person’s risk of developing periodontal disease, and patients with obesity have greater health care costs. However, the effect of obesity on periodontal treatment costs has not been examined. This retrospective cohort study used data from the electronic dental records of adult patients examined from July 1, 2010, through July 31, 2019 at a US dental school. Primary exposure was body mass index, which was categorized as obese, overweight, or normal. Periodontal disease was categorized using clinical probing measures. Fee schedules and procedure codes were used to compute the primary outcome, which was total periodontal treatment costs. A generalized linear model with gamma distribution was used to examine the relationship between body mass index and periodontal costs after controlling for initial periodontal disease severity and other confounding variables. Parameter coefficients and mean ratios with 95% CIs were estimated. The study sample included 3,443 adults, of whom 39% were normal weight, 37% were overweight, and 24% were obese. Mean (SD) total periodontal treatment costs for patients who were obese were considerably higher ($420 [$719]) than those for patients who were overweight ($402 [$761]) and patients who were normal weight ($268 [$601]). After controlling for covariates and disease severity, patients who were obese had 27% higher periodontal treatment costs than patients who were normal weight. The additional periodontal treatment costs attributable to obesity were greater than those attributable to either diabetes or smoking. The study results suggest that among patients at a dental school, those who were obese incurred substantially higher periodontal treatment costs than patients who were normal weight, independent of initial periodontal disease severity. The study findings have important implications for clinical guidelines and dental benefit design and coverage policies.