A new study of veterans demonstrated no link between prostate cancer (PCa) recurrence and metabolic syndrome (MetS), in contrast to some previous studies. Elevated low-density lipoprotein (LDL) levels and impaired fasting glucose, however, might have an effect.
“This analysis of a large cohort of veterans supports a role for lipid and glucose metabolism in PCa recurrence and contributes to a developing body of evidence that may support preventive recommendations if these findings are confirmed,” stated lead researcher Liam Macleod, MD, of the University of Washington School of Medicine in Seattle, and colleagues.
For the retrospective study, the investigators analyzed the relationship between MetS and biochemical recurrence of localized PCa (after prostatectomy or radiotherapy) among 1,706 predominantly Caucasian veterans. Most men had clinical stage T1a–T2a disease, Gleason 7, and PSA less than 10 ng/dL. Patients receiving active surveillance or androgen-deprivation therapy were excluded.
MetS was defined as any 3 of the following features:
- blood pressure greater than 130/85 mm Hg
- fasting blood glucose 100 mg/dL or higher
- waist circumference above 102 cm (40 inches)
- high-density lipoprotein (HDL) less than 40 mg/dL
- or triglycerides 150 mg/dL or above.
The researchers also separately examined LDL cholesterol levels (greater than 130 mg/dL).
After a median 41 months, 279 men experienced PCa recurrence. Contrary to previous research, the investigators found no associations between recurrence and MetS or any number of its components, according to results published in Prostate Cancer and Prostatic Disease. Although the researchers could not confirm a link between hypertension and PCa recurrence, for example, “the role for hypertension merits further investigation,” they stated.
Having a high LDL cholesterol level was associated with 33% greater odds of disease recurrence. “Our findings of an association between elevated LDL and PCa recurrence support the concept that cholesterol interactions may have a role in the protective effects of statins noted by some researchers,” the investigators stated.
In addition, having an impaired fasting glucose level was linked to 54% greater odds of PCa recurrence. The cytotropic effects of glucose and insulin-mediated stimulation of cancer growth factors are among the possible mechanisms, according to the researchers.
In light of the specialized population and the results of previous studies, the investigators encourage further research.
The new findings differ from those of other recent studies. For example, in a study published recently in European Urology (2015;67:64-70), Bimal Bhindi, MD, of the University of Toronto, and colleagues found that men with MetS versus no component of MetS had 54% increased odds of a PCa diagnosis, 56% increased odds of clinically significant PCa, and 56% increased odds of intermediate- or high-grade PCa. The study included 2,235 men without a prior PCa diagnosis who underwent a prostate biopsy.