Researchers at the National Cancer Institute in Bethesda have found that higher body mass index (BMI) correlated strongly with increased risk of death from prostate cancer. However, no such association was found between BMI or weight gain and the development of the cancer. The study is the first large, prospective study to identify increasing weight after age 18 as an independent, poor prognostic factor for prostate cancer.
The incidence of obesity has increased dramatically worldwide and in the US, 30% of American adults are categorized as obese. Obesity is linked to chronic medical problems, including heart disease and diabetes, while some studies also indicate higher BMIs are linked to some cancers.
Led by Margaret Wright at the National Cancer Institute in Bethesda, researchers followed 287,760 men, ages 50-71 years as part of the NIH-AARP Diet and Health Study to examine the individual impact of BMI and adult weight change on the incidence, severity and outcome of prostate cancer.
The researchers found that higher BMI and weight gain since the age of 18 were associated with significantly higher risk of death from prostate cancer. Men who were overweight (BMI 25-29.9) had a 25% higher risk, mildly obese men (BMI 30-34.9) had a 46% higher risk, and severely obese men (BMI greater than 35) had a 100%, or doubled risk.
The researchers concluded that although there is no evidence to suggest that the incidence of prostate cancer is higher in obese men, the risk of death from the disease increases as BMI increases.