Over the years it has been suggested, on and off, that bicycling may have impact on a man’s PSA levels and therefore on his potential risk for diagnosis of prostate cancer. However, there has never been any real evidence of such impact.
A new systematic review and meta-analysis of the available data — by Jiandani et al. — now seems to confirm that (based on the currently available data) there is no effect of bicycling on PSA levels in regular cyclists. However, the authors are careful to note that
- There have been a limited number of appropriate trials. (Only eight trials met the study inclusion criteria.)
- The numbers of patients in such trials have been small (with only 912 patients in total and a median sample size of just 42 participants)
- There have been no randomized controlled trials at all.
The authors report the following specific findings:
- Six studies of the eight studies investigated the acute pre-post change in PSA levels following bicycling activity (from a single 15-min bicycle ride to a 4-day cycling event).
- Two studies reported a total increase in PSA levels from baseline by up to 3.3 times.
- One study reported an increase in free PSA levels by 0.08±0.18 ng/ml.
- There were no changes in PSA levels in four studies.
- A single study compared PSA levels in elite/professional cyclists versus non-cyclists and showed no significant difference in PSA levels between the groups.
- Data from six studies were meta-analyzed and showed no significant increase in PSA levels from pre-cycling to post-cycling (mean change +0.027 ± 0.08 ng/ml, P = 0.74).
Jiandani et al. are careful to note that:
- Their study may “have low statistical power to detect a difference in PSA.”
- A higher sample size “may demonstrate statistical significance” but it may still not be clinically significant.
However, at this time there is no good reason to believe that cycling is necessarily a cause of an increased PSA level in men who bicycle on a regular basis. On the other hand, if you do not bicycle on a regular basis, it may not be the best idea to get a screening PSA test carried out within 48 hours of so of a long bike ride.
Filed under: Diagnosis, Risk | Tagged: bicycling, PSA, risk |
THE "NEW" PROSTATE CANCER INFOLINK 
Since it only requires a guy to skip the bicycle or exercise bike for 48 hours, I’ll stick with the recommendation to do so to play it safe. What is surprising are the occasional unanticipated PSA elevations wherein the physician had earlier performed a DRE and then drew the patient’s blood for the PSA test.
Lots of debate here. Another scenario in tagging along Chuck’s comment is a bowel movement, believe it or not. Anything that can jostle a prostate for that matter could in fact have some effect on PSA results — but we really don’t know to what degree. We do know that if one took a PSA test in the morning and again in the evening that a significantly different number could be seen … but we don’t know why. Suspects are the usual: sex during the day, medications (particularly allergy medications but not limited to), exercise, diet, illness (UTI or otherwise), etc.
What we have learned is that changes in PSA are more the norm than the exception. Thus more need for monitoring velocity over time. Especially the active surveillance guys need to understand this. What we also have learned is that surgical removal of the prostate results in more accurate PSA readings moving ahead. That these cases with rising detectable PSA are largely unaffected by any of the suspects listed above.
Tony:
While I am not obsessive about this, my general guidance to anyone getting PSA tests done repetitively (for whatever reason: annual PSA tests in high-risk men; men on active surveillance; men getting regular tests post-treatment) is to avoid any form of sexual activity the night before and to get the blood drawn at the lab first thing in the morning on an empty stomach … just as one would if one was getting blood drawn to check one’s cholesterol levels. That way one at least is wiping out the potential risk associated with inconsistency in timing of the tests and one’s recent food/alcohol intake. I am actually mildly surprised that some organization (e.g., the AUA) hasn’t issued some “good practice” guidance about this issue — but they would probably say we don’t have enough data to justify it.
And they’d be correct. No one knows if your suggested “guideline” would be a good practice based upon a myriad of reasons. It may provide for a consistent baseline I suppose. But it sounds more like an issue for the NCI to take up than the AUA. In the meantime, it’s really a best practice to let patients know that there is a solid reason for monitoring to be done over a period of time rather than a single test. And let them know that medications can in fact fluctuate PSA by as much as 100% if not more. We already know there are medications such as dutasteride and finasteride that can “mask” PSA by as much as 50%. And I have seen cases of PSA doubled by allergy medicine. Not sure how that would play out in the recommendations you have stated.
Tony:
I’m not in the business of writing guidelines. My only point is that if you are consistent about how and when you get your blood drawn, then over a series of tests you will be more likely to get a series of individually consistent results. There are certainly other factors (like other drug usage) that also have to be taken into account by individual patients and their physicians.
PSA level elevates from 5 year consistent level of 0.7 to 2.45 — this is after biking an hour the night before (12 hours). This may provide some significant info … I am retesting my PSA in a month and will discover that my PSA jumped specifically due to that activity — or, that the jump/anomaly is of concern.
I am 78 and have BPH with a prostate that weighs 58 grams and my PSA level has fluctuated between 1.40 and 2.30 ng/ml for many years. Last summer first time after year I retested the day after 4-5 days biking. It was 4.65, In 3 days it fell down to 3.33 and finally after 2 weeks down to 2.58 .I wonder if it shows something bad.
That also happened once before, when I was tested (3.17) a day after a vigorous sitting shoulder press on the machine then dropped again to my previous level in 10 days.
Yalçın:
Your really need to discuss this with your doctors to get a good answer to your question, but if this happened to me and I already had BPH I would simply get another test in 3 months time before I made any other decisions. The chances seem to be high that this is not a serious problem.