According to a Medwire news report, researchers are calling for high-quality studies to investigate the relationship between exercise and COPD, after a systematic review found a poor level of evidence.
Judith Garcia-Aymerich and colleagues reported that although they did establish that physical activity is often associated with exacerbation and mortality, the evidence about determinants of physical activity was lacking. The research team reviewed 86 studies that examined links between physical activity and its determinants and/or outcomes in patients with COPD.
The majority of the studies were cross-sectional and only half measured physical activity using a direct method, such as a pedometer. A total of 59 of the selected studies focused on determinants, while 23 focused on outcomes and four on both.
The Medwire news report notes that the researchers found that a large proportion of the studies investigated the effect of exercise training on physical activity; however, the results were inconsistent and the quality of the evidence was low because many did not include a control group or included a control group without randomization.
Only three studies tested the effect of pharmacological treatment on physical activity, with inconsistent results and “several methodological flaws” that resulted in quality of evidence being rated as very low, as noted on the Medwire news report.
Overall, the researchers found that the quality of evidence was better than that for determinants in terms of COPD outcomes despite fewer studies existing. Based on moderate quality evidence, low levels of physical activity were linked to a reduced risk of COPD exacerbations and mortality.
With the generally poor quality of evidence observed in this review, the researchers conclude that “[t]he research community should make an effort to conduct prospectively planned cohort studies and randomised trials to provide a stronger evidence base for determinants and outcomes of physical activity and for developing recommendations for or against treatments in clinical guidelines,” according to Medwire.