I found an interesting article in a recently published issue of the Journal of Addiction Medicine, Vol 7 (1) pages 58-65. This article describes the effect of opioids on PSA (prostate specific antigen) scores.
PSA is an enzyme normally found in low levels in the blood of men with healthy prostates. It’s elevated in a variety of prostate diseases. Notably, it’s elevated in men with prostate cancer, but it can also be elevated from other ailments that cause inflammation of the prostate.
Routine screening of men through checking the PSA levels is controversial, and some experts say routine screening of PSA leads to unnecessary prostate biopsies. They also say screening doesn’t reduce deaths from prostate cancer. However, many men specifically ask for PSA screening, and many doctors still check the PSA levels as part of a routine physical. PSA levels can be followed after a patient has been treated for prostate cancer, and elevated levels can mean a recurrence of the cancer.
In this study of Iranian men, male opioid addicts had 28% lower PSA levels than subjects that didn’t use opioids.
We already know that opioid use is associated with lower serum testosterone levels, so the authors of the study postulated that lower testosterone levels lead to lower PSA levels, but this was not the case, at least in this group of men. There was no correlation between serum testosterone levels and PSA levels in this study, so it did not appear that testosterone levels caused the lowered PSA levels.
Since prostate biopsies are performed on men with elevated PSAs the study authors were concerned that in opioid addicts, their lower PSA levels will fall below the threshold for biopsy. This could mean cancers could be missed in opioid users that might be detected in non-opioid users. Therefore, prostate cancers may not be detected in opioid addicts until the cancer is more advanced.
Indeed, in this study, more the men on opioids who were diagnosed with prostate cancer during the study period had higher grade prostate cancer than the men not on opioids who were diagnosed with prostate cancer during the study period.
This study suggests that for men on long-term opioids, PSA cut-offs should be lowered when deciding if the patient needs an evaluation for possible prostate cancer.