The effect of self-reported flossing behavior on cardiovascular disease events and mortality: Findings from the 2009-2016 National Health and Nutrition Examination Surveys.

Background: There is increasing evidence suggesting that daily oral hygiene self-care measures may alleviate cardiovascular disease (CVD) risk. The authors aimed to determine the influence of self-reported dental flossing behavior on the prevalence of CVD events, CVD-linked mortality, and a CVD risk marker of inflammation (ie, C-reactive protein [CRP]).

Methods: Data from 18,801 adult participants of the 2009-2016 National Health and Nutrition Examination Surveys were analyzed with regard to flossing behavior, prevalence of CVD events, mortality cause data, and CRP levels. Information on mortality was obtained from the US mortality registry, updated to 2019. Participants who answered the flossing question were divided into 4 groups according to their frequency of flossing: not flossing (0 d/wk); occasional flossing (1-3 d/wk); frequent flossing (4-6 d/wk); and daily flossing (7 d/wk). Multiple logistic regression and Cox proportional hazard regression were used for analysis.

Results: Daily flossing was associated with lower prevalence of CVD events after adjusting for age, sex, sociodemographic factors, and lifestyle habits (model 2); the odds ratio was 0.71 (95% CI, 0.59 to 0.85) for CVD prevalence in the daily flossing group compared with the not flossing group. The odds ratio for CVD prevalence for each additional day of flossing was 0.95 (95% CI, 0.93 to 0.98; P for linear trend < .001) in model 2, and remained statistically significant after model 2 was further adjusted for metabolic syndrome. Daily flossing compared with not flossing was associated with lower risk of experiencing CVD mortality (hazard ratio, 0.64; 95% CI, 0.49 to 0.84) in model 2. The hazard ratio of CVD mortality for each additional day of flossing was 0.94 (95% CI, 0.90 to 0.98; P for linear trend = .002) in model 2. Participants in the not flossing group had significantly elevated CRP levels, even after multivariable adjustments.

Conclusions: Poor flossing behavior is associated with higher prevalence of cardiovascular events, increased risk of experiencing CVD mortality, and elevated CRP levels.

Practical implications: Improvement in flossing behavior can have an additional benefit in the prevention of CVD events. Cardiologists need to advise patients to improve their personal oral hygiene practices, in addition to the standard diet and exercise advice.