Chewing areca nut as an independent risk factor for proteinuria in middle-aged men

No previous large-scale research has reported the association of chewing areca nut (AN) with proteinuria. The aim of this study was to investigate such an association in men over a 7-year study. In this cross-sectional research, we retrospectively reviewed the records of health check-ups in a community hospital setting from 2003 to 2009. Laboratory tests, medical histories, and the status of smoking cigarettes, drinking alcohol, and chewing AN were obtained for each participant. Proteinuria was defined as having +/- or heavier protein response (including +/- to 4+) in a urine test performed by an automated chemical analyzer. We compared characteristics in participants with and without proteinuria, and analyzed the adjusted risk for proteinuria with chewing AN in middle-aged men. We also compared the changes in adjusted risk for proteinuria under a stricter definition of proteinuria (≥ 1+ proteinuria). There were 11,991 men with a mean age of 58.94 ± 12.06 years. The prevalence of proteinuria in AN chewers was 13.7%, and 11.2% for non-chewers (p = 0.005). Of the 1381 participants with proteinuria, the proportion chewing AN was 15.3%, and 12.6% for those without proteinuria (p = 0.005). In the multivariate logistic regression analysis with three different levels of adjustment models, with adjustment factors for age, drinking, smoking, hypertension, diabetes, hyperlipidemia, body mass index, chronic kidney disease, anemia, liver dysfunction, and hyperuricemia, the odds ratios of proteinuria for chewing AN were 1.61, 1.55 and 1.40 (all p = 0.000). With the stricter definition of proteinuria, the odds ratios became weaker (1.40, 1.36 and 1.19; p = 0.009, 0.029 and 0.24). We concluded that chewing AN was independently associated with risk of proteinuria in middle-aged Chinese men.