Tobacco smoking associated with periodontal pocket development
KUOPIO, Finland: A study by researchers in Finland and the UK has found that self-reported daily smokers had a higher incidence of deepened periodontal pockets than those who had never smoked. The study also investigated the accuracy of self-reported smoking by assessing serum cotinine levels and found a positive association between these levels and the development of periodontal pockets.
Tobacco smoking is known to have a causal effect on the progression of periodontal disease. According to the study by researchers at the University of Eastern Finland in Kuopio, Oulu University Hospital in Finland and King’s College London in the UK, self-reports are the most common method of assessing an individual’s tobacco use; however, incorrect disclosure of smoking status and the level of tobacco consumption can lead to invalid data in studies that examine the effects of tobacco use. Together with the incidence of deepened periodontal pockets, the researchers therefore assessed study participants’ serum cotinine levels. Serum cotinine is the primary metabolite in nicotine and measuring it is a reliable quantitative biomarker for exposure to nicotine-containing tobacco products.
A total of 294 participants were included in the analysis, and smoking status was assessed through home interviews, resulting in study participants being categorised into the following groups: daily smokers, occasional smokers, quitters and never-smokers. Serum cotinine levels were measured using liquid-phase radioimmunoassay methodology, and a follow-up clinical oral examination was performed, where the depth of periodontal pockets was assessed using the World Health Organization periodontal probe.
Covariates were assessed, including participants’ socio-demographic factors—such as education—and dental behaviour and oral hygiene.
“The participants who developed periodontal pockets after four years were more likely to be males, less educated, daily smokers and had serum cotinine levels ≥ 42.0 µg/L than those with no periodontal pocket after four years,” the researchers found. After adjusting for confounding factors, an incidence rate ratio (IRR) of 1.59 was observed for daily smokers in comparison with never-smokers. Close to no elevated risk for periodontal pocket development was found for occasional smokers and quitters.
The amount of smoking was found to be associated with the development of deepened periodontal pockets in an exposure-dependent manner. “The IRRs for the highest category (20+ cig/day) varied from 2.03 to 2.41. In a fully adjusted model, 1–9 cigarettes/day was not associated with periodontal pocket development,” the study read.
In assessing the accuracy of self-reported smoking status, the researchers found a strong correlation in daily smokers between serum cotinine levels and the reported number of cigarettes smoked. “This study reveals that smoking is related to deterioration of periodontal health irrespective of whether the measurement of smoking is based on self-reports or serum cotinine level,” the researchers wrote, noting that the self-reported smoking was consistent with the serum cotinine levels found in study participants.
The study, titled “Effect of smoking on periodontal health and validation of self-reported smoking status with serum cotinine levels”, was published online on 8 May 2021 in Acta Odontologica Scandinavica, ahead of inclusion in an issue.