Obesity Is a Significant Risk Factor for Prostate Cancer at the Time of Biopsy

Abstract

Background Studies suggest obesity is associated with decreased prostate cancer risk. We hypothesized obesity is biologically associated with increased risk, though this is obscured due to hemodilution of PSA and larger prostate size. Methods Retrospective study of 441 consecutive men undergoing prostate biopsy between 1999 and 2003 at two equal access centers. The association between obesity (body mass index ≥30 kg/m2) and positive biopsy and Gleason ≥4+3 were estimated using logistic regression analysis adjusting for multiple clinical characteristics. Results 123 men (28%) were obese and 149 men (34%) had cancer. Median PSA and age were 5.7 ng/ml and 63.9 years. Obese men had significantly lower PSA concentrations (p=0.02) and larger prostate volumes (p=0.04). Obesity was not significantly related to age (p=0.19) or race (p=0.37). On univariate analysis, obesity was not associated with prostate cancer risk (OR 1.13, 95% CI 0.73–1.75, p=0.58). However, after adjusting for multiple clinical characteristics, obesity was associated with significantly increased prostate cancer risk (OR 1.98, 95% CI 1.17–3.32, p=0.01). After multivariable adjustment, there was no significant association between obesity and high-grade disease (p=0.18). Conclusions Without adjustment for clinical characteristics, obesity was not significantly associated with prostate cancer risk in this equal access clinic-based population. However, after adjusting for the lower PSA levels and the larger prostate size, obesity was associated with a 98% increased prostate cancer risk. These findings support the fact current prostate cancer screening practices may be biased against obese men.

Body mass index influences prostate cancer risk at biopsy in Japanese men

“…6,17 Other research from Western countries did not find a positive impact of BMI on the PCa risk at biopsy. 8 Accordingly, it is almost consistent among Western countries that overweight men have no elevated PCa risk at biopsy.…”

“…[3][4][5] The results of most prospective studies assessing the relationships between obesity and PCa risk have shown consistent results, whereas inconsistent results have been shown in studies investigating the impact of obesity on the PCa risk at biopsy in men with raised PSA; there have been positive, null and negative impacts of obesity on the PCa risk at biopsy reported for PCa or high-grade disease among Western populations. [6][7][8][9][10] The WHO currently defines overweight as a BMI of 25 kg/m 2 or greater and that of obesity as 30 kg/m 2 or greater. The limits for overweight and obesity were derived primarily in European populations, and correspond to risk thresholds for a wide range of chronic diseases and mortality.…”

Angiopoietin-Like Proteins Potential Therapeutic Targets for Metabolic Syndrome and Cardiovascular Disease

“…Thus, Angptl2 signaling might be a common key player in these 2 major diseases related to chronic low-grade inflammation. Obesity is known to increase the risk of several cancers, such as esophageal, 54,55 colon, 54,55 liver, 56 gall bladder, 55 pancreatic, 55,57 kidney, 55 prostate, 58 breast, 54,55 and uterine endometrial cancers. 54,55 Circulating inflammatory mediators, upregulated in obesity, including Angptl2, could be involved in carcinogenesis.…”

A cross-sectional study on prevalence of obesity and its association with dietary habits among college students in Abha, Saudi Arabia

“…3 Obesity is a major predisposing factor for type II diabetes, dyslipidemia, hypertension, cardiovascular diseases, metabolic syndrome and certain cancers. [4][5][6][7] World Health Organization stated approximately there were 400 million adults who were obese in 2005 in which the rates are higher among women. 8 The prevalence of obesity had increased in the Arabian Gulf region because of the economic rise happened between the year 1970 and 1980 and it was really alarming all the national health authorities.…”