Severe edentulism is a major risk factor influencing stroke incidence in rural Ecuador (The Atahualpa Project)

Background: There is no information on stroke incidence in rural areas of Latin America, where living conditions and cardiovascular risk factors are different from urban centers. Aim: Using a population-based prospective cohort study design, we aimed to assess risk factors influencing stroke incidence in community-dwelling adults living in rural Ecuador. Methods: First-ever strokes occurring from 1 June 2012 to 31 May 2016, in Atahualpa residents aged ≥40 years, were identified from yearly door-to-door surveys and other overlapping sources. Poisson regression models adjusted for demographics, cardiovascular risk factors, edentulism and the length of observation time per subject were used to estimate stroke incidence rate ratio as well as factors influencing such incidence. Results: Of 807 stroke-free individuals prospectively enrolled in the Atahualpa Project, follow-up was achieved in 718 (89%), contributing 2,499 years of follow-up (average 3.48 ± 0.95 years). Overall stroke incidence rate was 2.97 per 100 person-years of follow-up (95% CI: 1.73–4.2), which increased to 4.77 (95% CI: 1.61–14.1) when only persons aged ≥57 years were considered. Poisson regression models, adjusted for relevant confounders, showed that high blood pressure (IRR: 5.24; 95% CI: 2.55–7.93) and severe edentulism (IRR: 5.06; 95% CI: 2.28–7.85) were the factors independently increasing stroke incidence. Conclusions: Stroke incidence in this rural setting is comparable to that reported from the developed world. Besides age and high blood pressure, severe edentulism is a major factor independently predicting incident strokes. Public awareness of the consequences of poor dental care might reduce stroke incidence in rural settings.