Association between tooth loss and hypertension: A systematic review and meta-analysis

Objectives: Poor oral health status may increase the risk of cardiovascular disease. However, whether a specific association exists between tooth loss and hypertension is inconclusive. Accordingly, a quantitative systematic review was conducted to investigate the relationship between tooth loss and hypertension. Methods: Systematic search, data analysis and quality assessment were conducted on relevant literature published in PubMed, Embase, Web of Science and Cochrane Libraries until October 2021. Odds ratio (OR) with 95% confidence interval (CI) was used as effect size to evaluate the association between tooth loss and hypertension. Meta-regression and subgroup analyses were performed to identify whether difference was associated with study-level factors. Results: Of the 56 studies selected, 28 studies in 16 different countries involving 1,224,821 individuals were eligible for the systematic review. After adjustment for confounding factors, individuals with tooth loss had a higher risk for hypertension (OR 1.20; 95%CI 1.10-1.30, I² = 40.02%). With respect to the risk of hypertension on tooth loss, individuals with hypertension still had a higher risk for tooth loss (OR 1.35; 95%CI 1.07-1.62, I² = 51.10%). Age limitation of the included population is the major source of heterogeneity. However, studies in which the population was limited to the elderly did not report an increase in association between tooth loss and hypertension compared with studies without age limitation. Conclusions: The results suggest a bidirectional association between tooth loss and hypertension. Future longitudinal prospective studies are required to establish causality between tooth loss and hypertension. Clinical significance: Subjects with severe tooth loss should be carefully monitored for the manifestation of hypertension. The oral health status of hypertensive patients should also be meticulous maintained to prevent unwarranted tooth loss.