In patients with COPD, a link was observed between inhaled corticosteroid (ICS) use and the risk for cardiovascular disease (CVD), according to Hannah Whittaker, PhD, MSc. “Previous studies have reported mixed associations between ICS and CVD in people with COPD,” Dr. Whittaker wrote.
To fill this knowledge gap, Dr. Whittaker and colleagues conducted a random-effects metaregression and meta-analysis, published in Chronic Obstructive Pulmonary Disease. They used updated literature to examine the relationship between ICS-containing medications and CVD in patients with COPD. In their search for studies, they observed that CVD outcomes specifically included stroke-related events, heart failure, and myocardial infarction. “We also aimed to investigate study-related factors that modify the relationship between ICSs and CVD risk and stratify by subgroups of [patients with] COPD,” Dr. Whittaker and colleagues wrote.
Follow-Up Periods Greater Than 3 Years More Likely to Show Reduced CVD Risk
A total of 15 studies (N=240,903) met the criteria for inclusion. Pooled results from the metaanalysis showed a significant link between ICS-containing medication and reduced risk for CVD (HR, 0.87; 95% CI, 0.78-0.97). Modifying the relationship between ICS use and the risk for CVD were non-ICS comparators, follow-up time, and exclusion of patients with previous CVD.
“We found [a link] between ICS-containing medication and a decreased risk [for] CVD in people with COPD, suggesting that subgroups of patients with COPD may benefit from ICS use more than others, such as patients on long term ICSs,” the researchers pointed out.
Studies with follow-up periods greater than 3 years were considerably more likely to report a reduced risk for CVD compared with studies with follow-up periods of 3 years or less (ratio of HRs, 0.77; 95% CI, 0.62-0.95) (Table). Compared with studies that measured ICSs against placebos, those that compared ICSs with bronchodilators were more likely to show an increased risk for CVD (ratio of HRs, 1.54; 95% CI, 1.20-1.98; P=0.005). Finally, research that excluded patients with a history of CVD were more likely to show a reduced risk for CVD compared with studies that did not exclude patients with such a history (ratio of HRs, 0.68; 95% CI, 0.54-0.86; P=0.006).
Exact Cause of Association Between COPD & CVD Remains Unclear
The exact cause of the relationship between COPD and CVD remains unclear, according to the researchers. “The prevalence of CVD in [patients with] COPD is estimated to range between 14% to [more than] 60%,” they wrote. “People with COPD and CVD share common risk factors such as smoking, age, and exposure to air pollution. It is thought that patients who smoke are exposed to harmful particles that increase systemic inflammation, a characteristic of both COPD and CVD.”
Oxidation stress and hypoxia may also play a role in the relationship between CVD and COPD, the researchers added. “ICSs have been shown to reduce biomarkers such as lymphocytes and neutrophils and in turn improve lung function and reduce exacerbations,” they noted. “This reduced inflammation could, therefore, lead to a reduced risk [for] CVD in [patients with] COPD taking ICS medications.”
Further studies, they added, are needed to better understand this relationship and whether this association varies by COPD phenotype and patient characteristics.
