Not brushing teeth at night may increase the risk of cardiovascular disease

Abstract

In this study, we investigated whether tooth brushing timing affects cardiovascular disease risk. We enrolled 1,675 patients aged ≥ 20 years who were hospitalized for treatment, examination, or medical treatment. The participants were categorized based on tooth brushing: Group MN (brushing teeth after waking up and at night, n = 409), Group N (brushing teeth at night but not upon waking up, n = 751), Group M (brushing teeth after waking up but not at night, n = 164), and Group None (not brushing teeth at all, n = 259). The participants’ age, sex, smoking history, and follow-up results, was evaluated. Group M had four times as many men as women. Multivariate analysis of cardiovascular events showed significantly higher survival estimates in Group MN (P = 0.021) and Group N (P = 0.004) than those in Group None. Kaplan–Meier analysis of subgroups based on smoking status revealed that smokers in Group None had a significantly worse prognosis for cardiovascular onset events than smokers in other groups; non-smokers in Groups None and M showed a significantly worse prognosis on hospitalization. Our findings are limited to cardiovascular diseases and cannot be generalized to healthy populations. However, we suggest that brushing teeth at night is important for lowering cardiovascular disease risk.