Frequent toothbrushing plus regular dental flossing or interdental brushing may be linked to a reduced risk of stroke in middle-aged and older adults, according to a large study published on July 4 in the Journal of Dentistry.
It is believed to be the first study to explore worldwide whether flossing and interdental brushing frequency provide extra benefits for stroke prevention beyond increased toothbrushing frequency, the authors wrote.
“Promoting adjunctive oral hygiene practices could represent a simple, accessible, and population-based strategy for reducing ischemic stroke risk in middle-aged and older adults,” wrote the authors, led by Dr. Sang Min Park of the Seoul National University Hospital in Seoul, South Korea.
Worldwide, stroke is one of the leading causes of death. Although brushing daily is promoted widely for good oral health, the preventive effect of adjunctive oral hygiene practices, like flossing, on stroke risk is not clear.
To explore the link between comprehensive oral hygiene habits and stroke risk, a population-based retrospective cohort study using data from the Korean National Health Insurance Service-Health Screening cohort was conducted.
The study included data from 98,866 adults age 40 or older who underwent general and oral health exams during 2009-2010. These patients were followed from 2011 to 2019. Patients with preexisting cardiovascular disease, death before baseline, or missing data were excluded, the authors wrote.
Patients self-reported oral hygiene behaviors, including flossing. Incident stroke requiring hospitalization for two or more days and was classified as total, ischemic, or hemorrhagic stroke according to diagnostic codes was the primary outcome. Hazards models were used to estimate adjusted hazard ratios (aHRs) and 95% confidence intervals (CIs), they wrote.
Patients with good dental hygiene habits appeared to show a lower risk of stroke compared to those with poor practices.
Furthermore, patients who brushed at least twice per day and regularly used floss and interdental brushes had a 23% lower risk of ischemic stroke (adjusted hazard ratio: 0.77; 95% CI: 0.63 to 0.94). Those who increased how often they flossed and used interdental brushes appeared to be linked to a reduced risk of ischemic stroke among patients with missing teeth who brushed their teeth zero to one time per day, the authors wrote.
However, the study was not without limitations. The evaluation of dental hygiene practice frequency may not be accurate due to patients' self-reporting information, they wrote.
“Comprehensive oral hygiene behaviors, including regular toothbrushing, dental flossing, and interdental brushing, may contribute to stroke prevention beyond conventional vascular risk factor management,” Park and colleagues wrote.
