Abstract
Background. Cell-phone usage has increased dramatically over the last decade, along with a rising public concern over the health effects of using this device. The association between cell-phone usage and hypertension has not been examined before. Methods. We analysed data from 21,135 adults aged ≥18 years who participated in the 2008 National Health Interview Survey. Based on reported cell-phone use, participants were categorized as cell-phone nonusers, predominantly landline users, dual users of cell phone and landline, and predominantly cell-phone users. The main outcome of interest was self-reported physician-diagnosed hypertension (n = 6,793). Results. 43.5% of the participants were cell-phone nonusers, while 13.8% were predominantly cell-phone users. We found that cell-phone use was inversely associated with hypertension, independent of age, sex, race/ethnicity, smoking, alcohol consumption, education, body mass index (BMI), and physical activity. Compared to cell-phone nonusers, the multivariable odds ratio (95% confidence interval) of hypertension was 0.86 (0.75-0.98, P trend = .005) among predominantly cell-phone users. This inverse association between cell-phone use and hypertension was stronger in women, those aged <60 years, whites, and those with BMI <25 kg/m(2). Conclusion. We found that cell-phone usage was protectively associated with self-reported hypertension in a nationally representative sample of US adults.