Epidemiological Association of Tooth-loss with Hypertension in South African Adults

Studies from developed countries have suggested a causal relationship between chronic oral infections and cardiovascular diseases. However, no study has examined the relationship in less developed populations. Objective: To determine the association between tooth-loss (end-point of chronic oral infection) and hypertension in South African adults. Method: Logistic regression was used to examine this association in a nationally representative sample of 9098 adults of age 25-70 years who participated in the 1998 South African Demographic Health Survey (SADHS). Data was obtained through validated questionnaire administered by trained interviewers. Questionnaire included information on any experience of tooth loss (partial or complete), use of dental services, tobacco use and other known risk factors for hypertension, including family history of blood pressure (BP) and past diagnosis of diabetes and/or high cholesterol. Three readings of respondents' BP, height and weight were also recorded. Hypertension was defined as average BP ≥160/95 and/or being on antihypertensive medication. Results: Mean (±SD) age of participants was 43.3 (±12.1) years. The prevalence of hypertension and tooth-loss was 18.1% and 72.2% respectively. Tooth-loss was more common among those overweight/obese than among those of normal body mass index (BMI) (76.7% vs. 66.7%; p<0.01). Compared to those who reported daily brushing, non-daily brushers were more likely to be hypertensive (17.8% vs. 24.2%; p<0.01). Compared to those who had all their natural teeth, the age-adjusted odd ratio for hypertension was 1.43 and 2.23 for partially edentulous and completely edentulous respondents respectively. After adjusting for known risk factors for hypertension and dental care, being edentulous remained a significant risk factor for hypertension (OR; 95% CI = 1.37; 1.04-1.80). Conclusions: Our findings suggest that tooth-loss is an independent risk factor for hypertension in South African adults and, highlights the need for adoption of health promotion strategies that address both the risks for oral and general health.