Compared to white men, black men appear to have up to four-fold greater risk of developing prostate cancer as their body mass index (BMI) increases, according to a study published in JAMA Oncology.
To explore a possible connection between obesity and prostate cancer, investigators analyzed data collected between 2001 and 2011 by the Selenium and Vitamin E Cancer Prevention Trial.
The trial included 3,398 black men and 22,673 white men, all cancer-free and age 55 and up at the start. Medical histories were gathered, including information on smoking, diabetes, family history of prostate cancer, ethnicity, and education. BMI was also assessed.
Over a median follow-up of 5.6 years, the researchers found a 58 percent increased risk for prostate cancer among black men compared with white men. In terms of weight, the researchers found that obesity raised risk in black men as weight increased.
For black men with a BMI of 25 kg/m² or less, their risk for any prostate cancer was up 28 percent, while that risk jumped to 103 percent for black men with a BMI of 35 kg/m² or more.
In addition, the researchers found that obesity among black men was linked to greater risk of both aggressive and non-aggressive prostate cancer risk.
Compared with healthy-weight black men, severely obese black men more faced a 122 percent increased risk for low-grade prostate cancer. Their risk for high-grade disease was 81 percent higher.
Obese white men, meanwhile, were found to face a 33 percent higher risk for aggressive prostate cancer compared with normal-weight white men, and no greater risk for low-grade cancer.
In fact, obese white men appeared to face a 20 percent lower risk for low-grade prostate cancer, relative to their healthy-weight peers.