The purpose of this cross-sectional study was to investigate the association of periodontitis and/or tooth loss with hypertension by excluding the common confounders. Eighty-one Tanzanian women who were aged 46–58 years, nonsmokers, nonalcoholic drinkers, and on no medication underwent clinical examination. Multiple-regression analysis showed that the severity of periodontitis was significantly correlated with increased systolic blood pressure and diastolic blood pressure. Simple-regression analysis indicated that the severity of periodontitis was inversely correlated with 24-hour urinary excretion of potassium ( , ) and also inversely with the frequency of intakes of green vegetables ( , ) and fruits ( , ). Low-potassium intake in the diet mostly accompanied by low dietary fiber intake increases BP as well as periodontal inflammation. Potassium intake may be an important factor linking periodontitis and hypertension in middle-aged nonsmoking and nonalcoholic women on no medication, although chronic inflammation such as periodontitis may cause hypertension through a more direct mechanism. 1. Introduction Periodontitis, which affects a large number of adults globally, is epidemiologically related to atherosclerotic vascular diseases and metabolic syndrome [1, 2]. Periodontitis as chronic inflammation destroys the supporting structure of the teeth and increases the level of C-reactive protein (CRP) [3–5]. Recent attention has focused on elevated serum CRP, a marker of systemic inflammation, as a strong and independent risk factor or predictor of hypertension (HT) [6]. The systemic response to periodontal infection is a possible pathway underlying the observed association between periodontitis and increased risk for HT. Epidemiological systematic examinations about the noted relationship between periodontitis and vascular diseases should be conducted among healthy subjects who have never smoked [7] because smoking is regarded as a strong confounder and may spuriously inflate the association between periodontitis and vascular diseases. Alcohol consumption is also one of the risk factors that can lead to the development of not only HT [8] but also periodontitis [9]. In nonsmoking menopausal Japanese women, tooth loss but not periodontitis was proven to be significantly associated with an increased risk of HT [10]. Medical care is also a confounding variable that strongly affects epidemiological studies in developed countries such as Japan, where epidemiological analysis on the association between vascular diseases and oral health may be complicated by the
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