The Relationship between Body Mass Index and Diabetes with Serum Prostate-Specific Antigen Levels in the Elderly

Prostate-specific antigen (PSA) is the most practical screening test for prostate cancer. Given the importance of screening for cancer detection, determining a specific threshold for abnormal PSA levels has special significance in this disease. Because the threshold can be changed by factors such as diabetes and obesity, this study aimed to determine the association between PSA levels with BMI and diabetes. This was a cross-sectional study and part of the health status evaluation plan of the elderly in Amirkola, Mazandaran, Iran (AHAP=Amirkola Health and Ageing Project), which was conducted on all 60 year and older men in Amirkola from 2011 to 2012. Data was collected through questionnaires, examination and blood sampling. The levels of PSA and testosterone were measured by ELISA. Body mass index (BMI) was calculated for all patients and diabetes was determined based on the previous history of the disease or FBS≥126 mg/dl, on two occasions. This study included 792 elders with an average age of 69.76±7.62 (age range 60–90 years) with a mean PSA of 1.88±2.98, testosterone of 4.77±4.10, fasting blood sugar of 112.92±40.08, and BMI of 26.04±4.01. There was a significant association between PSA and BMI (p=0.001) so that the group BMI≥30 showed lower values of PSA compared to the BMI<25, but there was no correlation between PSA levels and diabetes. Based on findings of this study, the levels of PSA should be interpreted with caution in screening for prostate cancer in obese patients and further investigation is needed in this area.