High BMI associated with lower urinary tract symptoms in older men

September 1, 2011

Obesity increases the risk of lower urinary tract symptoms in older men, whereas exercise potentially prevents LUTS in this population.

Despite the negative effect of LUTS on public health, its independent association with increased mortality and risk of falls, and the high cost associated with the diagnosis and treatment of LUTS in the United States, with estimates exceeding $6 billion, little research has focused on LUTS prevention, said first author J. Kellogg Parsons, MD, MHS.

Dr. Parsons and colleagues used data from the Osteoporotic Fractures in Men (MrOS) study to examine the association between adiposity and physical activity with incident LUTS in community-dwelling older men. The MrOS study enrolled 5,994 men from March 2000 through April 2002 on whom extensive information on prostate disease and LUTS are collected. All men were 65 years of age or older at baseline.

The onset of LUTS was defined as any of the following at a follow-up clinic visit, which occurred at a mean of 4.6 years after the baseline visit:

There were 1,695 men 65 years of age or older who qualified for the study (675 men 65 to 69 years of age, 852 men 70 to 79 years of age, and 168 men 80 years of age or older). Of these, 524 developed LUTS by the follow-up visit.

"We saw a pretty strong correlation between baseline obesity and later development of LUTS," said Dr. Parsons, associate professor of surgery at the University of California, San Diego. "The men who were obese at baseline were the ones most likely to develop LUTS at the last visit."

Compared with men with a body mass index less than 25 kg/m2 , those with a BMI of 25 kg/m2 to 29 kg/m2 had a 29% increased risk of developing LUTS, and those with a BMI in excess of 30 kg/m2 had a 41% increased risk (p=.05).

"When we looked at physical activity, we saw an inverse association [between activity and development of LUTS]," he said.

The odds of developing LUTS declined by 29% in men whose level of physical activity, as determined by the Physical Activity Scale for the Elderly, was in the highest quartile compared with sedentary men (p=.03). Men who reported walking daily had a 20% decreased risk of developing LUTS compared with those who didn't walk (p=.03).