Relationship of body mass index and other anthropometric measures and prostate specific antigen, NHANES 2001–2002

Abstract

4649 Background: Obesity has been suggested to be a risk factor for prostate cancer. However, there has been limited information examining the relationship between body mass index (BMI) and other anthropometric measures such as triceps thickness (TT) and waist circumference (WC) and prostate specific antigen (PSA), a marker used in screening for prostate cancer. Methods: We analyzed data from the 2001–2002 National Health and Nutrition Examination Survey (NHANES), a cross-sectional survey of a nationally representative sample of the non-institutionalized civilian US population. Participants in this study were limited to men aged 40 years and older without previously diagnosed prostate cancer (n = 1320). Weighted analyses were done overall and within three racial/ethnic groups [non-Hispanic whites (white), non-Hispanic blacks (black), or Mexican Americans (Mexican)]. BMI, TT, and WC were examined as both as a continuous and as a categorical variable. Three linear regression models were fit to determine the individual effect of BMI, TT, and WC on PSA within each racial/ethnic group after adjusting for age. Results: Among white men, the median PSA was 1.09 ng/mL [95% CI (0.96, 1.30)] for men with a normal BMI, 0.80 [95% CI (0.70, 0.94)] for overweight men, 0.83 [95% CI (0.74,0.95)] for obese men, and 0.74 [95% CI (0.56,1.22)] for severely obese men. Among black men, the median PSA for men was 0.83 [95% CI (0.70, 1.94)] and remained constant across BMI levels. Among Mexican men, the median PSA was 0.92 [95% CI (0.82, 1.23)] for men with a normal BMI, 0.91 [95% CI (0.81, 1.07) ] for overweight, 0.73 [95% CI (0.54,1.14)] for obese, and 0.59 [95% CI (0.39,1.06)] for severely obese men. In linear regression models controlling for age, a significant non-linear relationship was seen with BMI and PSA for both white (p = 0.010) and Mexican men (p < 0.001) but not for black men (p = 0.167). Increased TT was associated with decreasing PSA for black and Mexican men. Increased WC was associated with decreasing PSA for white and Mexican men. Conclusion: These data do suggest racial/ethnic differences of PSA across BMI categories as well as other anthropometric measures. This finding may help inform practitioners about the relationship of anthropometric measures on PSA levels. No significant financial relationships to disclose.