As ancillary findings, our analyses overall substantiated the role of other known parameters as predictors of total PSA and free/total PSA ratio in the general population, such as age, race/ethnicity, smoking habit, obesity, diabetes mellitus, personal history of BPE, and concomitant use of non-steroidal anti-inflammatory drugs (NSAIDs), statins, or 5-ARIs. Here, KLK3 is linked to obesity due to melanocortin 4 receptor deficiency.