Encourage men to improve their fitness levels to help them lower their prostate cancer risk
Men should be encouraged to improve their fitness levels to help them lower their chances of developing – though not dying from – prostate cancer.
That is the conclusion of paper published online today (31 January) in the British Journal of Sports Medicine. It has two first authors: Kate A Bolam and Emil Bojsen-Møller, both of whom are based in the Department of Physical Activity and Health at the Swedish School of Sport and Health Sciences GIH in Stockholm, Sweden.
There are relatively few known risk factors for prostate cancer, note doctors Bolam and Bojsen-Møller and five colleagues. And while there’s good evidence for the beneficial effects of physical activity on the risk of several cancers, the associations with prostate cancer are less clear-cut.
Most studies have assessed fitness at only one time point, with none examining the potential impact of fitness on both the risk of developing and dying from prostate cancer, the researchers state. They wanted to discover whether improvements in cardiorespiratory fitness might, over time, influence these risks, drawing on a national occupational health profile assessment database.
The database collected information on physical activity, lifestyle, perceived health, measurement of body mass and height, and the results of at least two cardiorespiratory fitness tests, measured by peddling on a stationary cycle, for 57,652 men out of a total of 181,673.
Annual cardiorespiratory fitness measurements were expressed as absolute and relative V02 max – the amount (volume) of oxygen the body uses while exercising as hard as possible – and divided into groups according to whether these increased annually by more than three per cent, fell by more than three per cent, or remained stable. In order to assess whether change in fitness on prostate cancer risk varied by baseline fitness, the Stockholm-based researchers created three groups of equal size of low, moderate, and high cardiorespiratory fitness.
For the incidence analysis, every participant was monitored from the date of the last assessment to the date of their prostate cancer diagnosis, or death from any cause, or until 31 December 2019, whichever came first.
For the mortality analysis, their survival was tracked from the date of their second assessment to either the date of death from prostate cancer, death from any cause, or until 31 December 2019, whichever came first.
During an average period of nearly seven years, 592 men (1 per cent of the total sample) were diagnosed with prostate cancer, and 46 (0.08 per cent) died of their disease.
The results highlight the importance of [cardiorespiratory fitness] for prostate cancer risk, which has been challenging to determine with single time point studies [Kate A Bolam and Emil Bojsen-Møller et al]
An annual percentage increase in absolute cardiorespiratory fitness was associated with a two per cent lower risk of prostate cancer, but not death, after accounting for potentially influential factors, including age, education level, year of test, weight (BMI), and smoking status.
When participants were grouped according to whether their cardiorespiratory fitness had increased, remained stable, or had fallen, those whose fitness had improved by three per cent or more a year were 35 per cent less likely to develop prostate cancer than those whose fitness had declined, after accounting for potentially influential factors.
When the participants were grouped by their cardiorespiratory fitness at their first assessment, the association between fitness and a reduction in prostate cancer risk was only statistically significant (15 per cent lower) for those with a moderate level of fitness to begin with.
As the study was observational in nature, it cannot, as such, establish causal factors, added to which genetic factors have a major role in both a person’s cardiorespiratory fitness and cancer risk, the researchers acknowledge.
Nevertheless, doctors Bolam and Bojsen-Møller and colleagues conclude: ‘The results highlight the importance of [cardiorespiratory fitness] for prostate cancer risk, which has been challenging to determine with single time point studies.’ They add: ‘Improvements in [cardiorespiratory fitness] in adult men should be encouraged and may reduce the risk of prostate cancer.'
To access the full version of the article – titled Association between change in cardiorespiratory fitness and prostate cancer incidence and mortality in 57 652 Swedish men doi: 10.1136/bjsports-2023-107007 – click
Author: I A McMillan
Share it with
