The predictive role of the total potassium intake and odds of breast cancer: a case-control study.

ABSTRACT

BACKGROUNDS Dietary potassium can play an important role in decreasing inflammatory factors as a protective factor for cancers. In this case-control study, we aimed to assess the possible association between dietary potassium intake and the risk of breast cancer (BC) among Iranian adult women. METHODS: The present case-control study was conducted at Shohada and Imam Hossain hospitals, in Tehran. The study included 134 newly diagnosed cases of BC and 267 controls. A validated semi-quantitative 168-item food frequency questionnaire was used to compute the potassium intake. Logistic regression, adjusted for potential confounders, was used to estimate odds ratios(ORs) and 95% confidence intervals(CI) of BC according to tertiles of potassium intake. RESULTS: The mean(M) ± standard deviation(SD) of age and body mass index (BMI) were 47.9 ± 10.3 years and 29.4 ± 5.5 kg/m2, respectively. Also, the M ± SD of potassium intake for the control and case groups was 1616 ± 293 and 1542 ± 338 (mg/1000 Kcal), respectively. In the multivariable-adjusted model for potential confounders, the higher total potassium intake was associated with decreased odds of BC (OR 0.35, 95%CI 0.19-0.62, P for trend < 0.001). Moreover, an inverse relationship was observed between potassium from plant sources (OR 0.39, 95%CI 0.22-0.69, P for trend = 0.001) and fruit and vegetable sources (OR 0.49, 95%CI 0.28-0.87, P for trend = 0.016) and odds of BC. CONCLUSIONS: Our findings suggested that diet rich in potassium may have a predictive role to reduce the odds of BC.