Impact of Obesity and Weight Change After Prostate Cancer Treatment

By Patrick Daly - Last Updated: December 2, 2022

Researchers, led by Kassandra Dindinger-Hill, evaluated how obesity and weight change affect survival and cardiovascular outcomes following prostate cancer treatment. Dindinger-Hill, presenting at the 23rd Annual Meeting of the Society of Urologic Oncology, reported that pretreatment obesity and post-treatment weight gain were associated with worse cardiovascular-specific and all-cause mortality, but not with prostate cancer-specific survival.

The study included 5077 men with prostate cancer and a median age of 64.3 years (interquartile range, 59.0-70.0 years). Participants were categorized as healthy, overweight, or obese based on body mass index ranges of ≤25 kg/m², 25-30 kg/m², and ≥30 kg/m², respectively. Researchers measured body weight changes as the percent difference in body weight between the first and second postdiagnosis measurements, which were a median of 5.02 years apart.

Prostate Cancer-Specific Survival Not Linked to Obesity

According to the authors, 35.3% (n=1793) of the cohort was overweight and 12.7% (n=644) was obese. Obesity prior to prostate cancer treatment was significantly correlated with cardiovascular disease-specific mortality (hazard ratio [HR], 1.62; 95% CI, 1.05-2.50) and all-cause mortality (HR, 1.34; 95% CI, 1.07-1.67). Likewise, obesity after treatment was associated with significantly increased cardiovascular disease-specific mortality (HR, 1.83; 95% CI, 1.31-2.56) and all-cause mortality (HR, 1.37; 95% CI, 1.16-1.64).

The researchers found a relative body weight change of more than 5% from pretreatment weight was associated with increased cardiovascular disease-specific mortality (HR, 1.48; 95% CI, 1.03-2.14) but not all-cause or prostate cancer-specific mortality compared with patients with stable weight, defined as <3% relative weight change.

“Post-treatment weight gain and weight gain during treatment were associated with worse cardiovascular- and all-cause-specific mortality, respectively,” the researchers summarized. “These findings have important implications for prostate cancer survivors and may inform future lifestyle interventions.”