Study Links High Body Mass and Large Waist to Hearing Loss

Researchers have used data from a 20-year prospective study to determine that a high body mass and a large waist are both associated with self-reported hearing loss. In an analysis of 68,421 women aged 25 to 42 at the start of the study, a team including investigators from Brigham and Women’s Hospital, the Harvard School of Public Health, and Vanderbilt University School of Medicine found the risk for hearing loss increased along with body mass index (BMI) among study participants. Researchers controlled for age, smoking, diabetes, hypertension, and other factors, and determined women with a BMI of 25 to 29 saw an 8 percent increased risk of hearing loss, compared to women with a BMI under 25. Women in the 30 to 34 BMI range were found to be at 11 percent greater risk. Those in the 35 to 39 range were at a 16 percent increased risk, with that number reaching 19 percent among women with a BMI above 40. The level of risk associated with larger waist circumference went up in a similar fashion. The study also found that moderate physical activity, even as little as 4 hours of walking per week, reduced the risk for hearing loss, with researchers noting no further advantage to more vigorous exercise. Taking BMI and waist circumference into account, study authors found that women who were the most physically active had a 17 percent lower risk of hearing loss in comparison to women who were the least physically active, according to Sharon Curhan, MD, MSc, a clinical researcher at Brigham and Women’s Hospital, and lead study author. “A complex interaction of factors all contribute to acquired hearing loss,” says Curhan, “including age, genetics, noise exposure, some medical conditions, and certain medications.” This particular study focused on identifying preventable contributors to hearing loss, such as diet and lifestyle factors that can be modified, and may help reduce risk, she adds. “My hope is that people become aware that much of hearing loss is avoidable, and may not be an inevitable part of getting older,” says Curhan. “That means there are things we can do to prevent it. [Helping patients] to maintain a healthy weight and to stay physically active helps prevent a variety of important medical conditions, including hearing loss.” The findings originally appeared in the December issue of The American Journal of Medicine. —Mark McGraw Reference Curhan S, Eavey R, et al. Body Mass Index, Waist Circumference, Physical Activity, and Risk of Hearing Loss in Women. The American Journal of Medicine. 2013.