The Weight of Weight on Prostate Cancer Survival

Prostate cancer patients who were obese at diagnosis had greater death risks

(RxWiki News) How much we weigh in relation to our height matters. In other words, body mass index (BMI) matters. If we’re carrying around too much fat, our chances of all sorts of diseases are — well — fattened. Our weight at the time we’re diagnosed with a disease may matter as well.

A recent study revealed that men who were overweight or obese when they were diagnosed with prostate cancer were more likely to die from the disease than their healthy-weight counterparts.

This link was particularly strong in men with the most aggressive forms of prostate cancer.

"Maintain a healthy weight."

Reina Haque, PhD, a researcher at Kaiser Permanente Southern California's Department of Research & Evaluation in Pasadena, California, led this case-control study to determine if a man's BMI at the time of prostate cancer diagnosis was related to prostate cancer mortality.

The study compared men who died from prostate cancer (cases) with men who did not die from the disease (controls).

A total of 751 men diagnosed with prostate cancer between 1971 and 2001 were enrolled in the study. All of these men had undergone a radical prostatectomy (surgical removal of the prostate).

The 323 patients who died were matched with 428 controls.

The men were placed into three groups, according to their BMI scores at the time of diagnosis: healthy weight (BMI of 18.5 to 24.9), overweight (BMI of 25 to 29.9) and obese (BMI greater than 30).

Nearly 43 percent of the men in the study were overweight or obese at the time of their diagnosis, and 30 percent of cases were obese, compared to 22 percent of the controls.

Overall, men who were obese when they were diagnosed had a 50 percent increased risk of dying from the disease compared to healthy-weight men.

When the researchers looked at Gleason scores — a measure of the aggressiveness of prostate cancer on a 2 to 10 scale — risks of dying rose along with increasing BMI.

Overweight or obese men with a Gleason Score of 8 or more were 2.37 times more likely to die of prostate cancer than men who had healthy weights at the time of diagnosis.

This association remained intact, even after adjusting for other risk factors such as PSA (prostate-specific antigen) levels at diagnosis, lymph node status (if cancer had or had not spread to nearby lymph nodes) and other clinical factors the researchers examined.

"Here's yet another study which emphasizes the relationship of being overweight to an adverse outcome," E. David Crawford, MD, professor of surgery, urology and radiation oncology and head of the Section of Urologic Oncology at the University of Colorado Health Sciences Center (UCHSC) in Denver, told dailyRx News.

"As I have repeated many times, 'What is heart healthy is prostate healthy,' and being overweight, along with a lack of exercise, does not benefit either organ," Dr. Crawford said.

“These results suggest that BMI at diagnosis is strongly correlated with prostate cancer mortality, and that men with aggressive disease have markedly greater odds of death if they are overweight or obese,” the authors wrote in conclusion.

They noted that additional study is needed to determine if lifestyle choices, such as diet and physical activity, could extend prostate cancer patient lives.

"Moving forward, we are hoping future studies will examine the effect of weight loss and other lifestyle modifications on prostate cancer mortality," Dr. Hague said in a prepared statement.

Additional research could also look at the relationship between BMI and death risks in men treated with radiation or hormone therapy, the researchers added.

This study was published in the September/October issue of Obesity Research & Clinical Practice.

The US National Institutes of Health/National Cancer Institute supported this study.

No conflicts of interest were disclosed.

Review Date: 
October 30, 2013