Pulmonary rehabilitation mitigates depression, anxiety symptoms in COPD
Pulmonary rehabilitation significantly improves symptoms of depression and anxiety in patients with COPD, according to a study.
“The evidence of effectiveness for pulmonary rehabilitation in people with COPD is strong. This message is frequently distilled from the important findings of the Cochrane Review on this topic by McCarthy and colleagues. However, despite including a large number of studies, the scope of outcomes for that Cochrane Review was narrow. There is also some debate regarding whether some interventions truly meet the accepted modern definition of pulmonary rehab, and randomized controlled trials comparing pulmonary rehab to usual care are no longer indicated,” Christian R. Osadnik, PhD, from the department of physiotherapy at Monash University and Monash Lung and Sleep at Monash Health, in Melbourne, Australia, wrote in an email to Healio Pulmonology. “This review therefore aimed to scrutinize the pulmonary rehab literature and determine its effect on mental health outcomes.”
For this systematic review and meta-analysis, Osadnik and colleagues included 11 randomized controlled trials involving 734 patients with COPD that compared pulmonary rehab with usual care. Pulmonary rehab was defined as exercise training that lasted at least 4 weeks or eight sessions with or without education or psychological support. Usual care was defined as the absence of any formal intervention that could improve anxiety or depression, including exercise, education or self-management programs.
Improved depression, anxiety symptoms
For the analysis, the researchers converted pooled effect estimates to scores equivalent to the Hospital Anxiety and Depression Scale (HADS).
After pulmonary rehab, as compared with usual care, the pooled standardized mean difference was –0.7 (95% CI, –0.87 to –0.53), which equated to mean difference of –2.5 (95% CI, –3.1 to –1.9) on the HADS Depression subscale. Additionally, these clinically meaningful benefits following pulmonary rehab were observed across both programs lasting up to 8 weeks and those lasting longer than 8 weeks (P = .63).
The researchers deemed the certainty of this evidence to be moderate, downgrading this judgment one level due to perceived risks of bias across many of the included studies.
Pulmonary rehab also improved anxiety symptoms, although the benefit was smaller than that seen for depression, according to the data. After pulmonary rehab, as compared with usual care, the pooled standardized mean difference was –0.53 (95% CI, –0.82 to –0.23), which equated to a mean difference of –2.2 (95% CI, –3.1 to –1) on the HADS Anxiety subscale. The magnitude of difference between shorter and longer programs again did not differ, but the pooled effect was only statistically significant in the group of programs lasting 8 weeks or less.
“The fact that pulmonary rehab was found to benefit symptoms of anxiety and depression in people with COPD was not surprising. After converting the magnitude of effect to a HADS-equivalent score, we were pleased to see this benefit could also be considered clinically relevant, as it exceeded the minimally important difference threshold for this instrument. We did not, however, expect to observe a slightly larger margin of effect for symptoms of depression compared to those of anxiety,” Osadnik said.
In post hoc exploratory meta-regression analyses, age, sex, disease severity, study year and program duration were not significant predictors of anxiety or depression symptoms at the end of pulmonary rehab.
The researchers acknowledged that the risk of bias as well as other factors inherent to reviews and meta-analyses potentially limit their findings. However, they noted that the data imply that pulmonary rehab appears to improve anxiety and depression symptoms, which often affect patients with COPD.
“The main take-home message for pulmonary rehab referrers and providers is that symptoms of anxiety and/or depression should not be considered a deterrent from undertaking pulmonary rehab — the intervention is likely to confer some benefit. Of course, average data from patients enrolled in clinical trials may not accurately translate into expected effects for individuals in clinical practice, but the message is nonetheless positive. Additionally, lack of observed difference between programs of shorter or longer length should be reassuring considering the large variability that exists between programs at different center,” Osadnik said.
He also noted that there are many opportunities for future research.
“Responder analyses are indicated to characterize those who do and do not respond to pulmonary rehab in terms of mental health symptoms including identification of the potential predictors of non-response. There is also some confusion in the literature regarding the impact of mental health symptoms on pulmonary rehab success. For example, do very high or very low symptoms affect responsiveness to treatment? And, we do not currently know how exactly to tailor the many working parts of pulmonary rehab in order to maximize its benefits on mental health outcomes. These are all important questions to answer in the future,” Osadnik told Healio Pulmonology.– by Melissa Foster
For more information:
Christian R. Osadnik, PhD, can be reached at firstname.lastname@example.org; Twitter: @COsadnik.
Disclosures: The authors report no relevant financial disclosures.