Statins, commonly used to lower blood cholesterol levels, can help chronic obstructive pulmonary disease (COPD) patients by preventing or treating COPD-related comorbidities, and by improving patients’ lung function and exercise capacity, according to a meta-analysis study of existing research data.
Results from the meta-analysis, titled “Effectiveness of long-term using statins in COPD – a network meta-analysis,” were published in the journal Respiratory Research.
COPD-related comorbidities can significantly worsen a patient’s prognosis and outcomes. Among these, cardiovascular diseases and pulmonary hypertension are especially prevalent in COPD patients.
Likewise, chronic inflammation is linked to disease progression in COPD, and high levels of C-reactive protein (CRP; a marker of inflammation) and interleukin-6 (IL-6, a signaling protein produced by immune cells) are known to associate with poorer outcomes.
Statins are widely used to treat cardiovascular conditions and hypercholesterolemia (high cholesterol levels). A growing number of recent studies also suggest that statins can have beneficial effects on COPD.
According to previous studies, statin use is associated with lower all-cause mortality and fewer COPD exacerbations or flares, which are linked to disease worsening. But whether statins reduce inflammation and pulmonary hypertension in COPD patients is not clear.
Researchers in China performed a so-called meta-analysis, comparing results from existing publications on the possible link between statins and different clinical parameters observed in COPD patients.
The meta-analysis first identified 988 studies on COPD and statins use, published between January 1990 and March 2018. Of these, 53 studies were included in the final analysis.
The studies included results of statin-linked all-cause mortality, heart disease-related mortality, COPD mortality, COPD acute exacerbations, inflammatory markers (namely CRP, IL-6, IL-8, and TNF-α), lung function tests of FEV1% and FEV1/FVC%, the six-minute walk test (a test assessing exercise capacity), total cholesterol, triglycerides, and pulmonary hypertension.
Patients in the analyzed studies ranged in number from 40 to 68,754, and study durations ranged from one to 120 months. Researchers compared results between different types of statins whenever data were available.
Results showed that although statins did not reduce heart disease-related mortality, they significantly reduced the risk for all-cause mortality by 28%, for COPD-associated mortality by 28%, and of acute exacerbations related to COPD by 16%.
Since chronic inflammation plays an essential role in COPD development, researchers then analyzed the effects of statins on inflammatory markers associated with COPD, namely CRP, interleukins IL-6 and IL-8, and TNF-α. Overall, they found significant reductions in all markers with statin use.
The team also found that, compared with other statins, Fluvastatin, Atorvastatin and Rosuvastatin were more effective in reducing C-reactive protein levels — one of the most studied biomarkers in COPD.
Likewise, a significant reduction in pulmonary hypertension in COPD patients was seen with statin treatment. Specifically, researchers found that Atorvastatin and Fluvastatin were the most effective statins in reducing pulmonary hypertension in these patients.
Other benefits of statin treatment seen in COPD patients included better lung function, as measured by forced expiration volume (FEV1) and forced vital capacity (FVC), and increased exercise performance (measured by the six-minute walk test).
Overall, results suggested that long-term use of statins can benefit COPD patients, working to possibly slow or prevent disease progression by slowing or preventing comorbid conditions.
“In conclusion, our network meta-analysis showed that long-term using statins reduced inflammatory factors including CRP and IL-6, increased lung function index including FEV1% and FEV1/FVC%, and reduced the risk of [COPD acute exacerbation], heart disease-related mortality and all-cause mortality,” the researchers wrote.
They also noted that among the statins analyzed, “Fluvastatin and Atorvastatin are more effective in reducing CRP and PH in COPD patients.”