People with chronic obstructive pulmonary disease (COPD) have an increased risk of severe illness, hospitalization, and death if they become infected with the influenza virus, according to a Canadian study. Researchers emphasize that getting a flu vaccine can significantly reduce these risks.
The study, published in the journal Chest, is titled “Effectiveness of Influenza Vaccination on Hospitalizations and Risk Factors for Severe Outcomes in Hospitalized Patients With COPD.”
The flu is a respiratory illness caused by the influenza virus, with symptoms including fever, sore throat, and coughing. Although it is manageable in normal cases, the flu can cause severe complications, including bacterial infections of the lungs.
Children, elderly people, and those with chronic disorders (such as lung diseases, including COPD) are at higher risk of flu-related complications. Because of this, the World Health Organization (WHO) recommends the influenza vaccine for these high-risk groups.
However, “the effectiveness of influenza vaccination in reducing influenza-related hospitalizations among patients with COPD is not well-described, and influenza vaccination uptake remains suboptimal,” researchers said.
Using data from the Serious Outcomes Surveillance (SOS) Network of the Canadian Immunization Research Network (CIRN), the trial (NCT01517191) encompassed information from 46 hospitals, including data from 4,198 hospitalized COPD patients with known vaccination status. The SOS Network collects information about influenza and related illnesses to better understand their outcomes, especially in high-risk groups.
The team analyzed data from four winter seasons, between 2011 and 2015, analyzing nasopharyngeal swabs (samples from the back of the nose or throat) to diagnose the flu. There were 1,833 influenza infections among the patients analyzed.
Results showed that the consequences of the flu can be severe in COPD patients. About 2 in 10 patients (17.2%) required intensive care, and about 1 in 10 patients (9.7%) died because of the flu, compared with 12.1% and 7.9%, respectively, in those not infected with the flu virus.
In addition, more hospitalized COPD patients with the flu required mechanical ventilation (8.7%), compared with patients who tested negative for the flu (5.2%).
The team found that the “influenza vaccine was associated with a 38 percent reduction in influenza-related hospitalizations among patients with COPD,” Sunita Mulpuru, MD, of the Ottawa Hospital Research Institute, the study’s first author, said in a news release. This observation suggests that COPD patients can benefit from the flu vaccine.
“Given the results of this study, we strongly encourage patients with COPD to receive the influenza vaccine each year as a protective measure against influenza and its serious health consequences,” Mulpuru said.
Still, despite its benefits, only 66.5 percent of the COPD patients analyzed had been vaccinated.
Researchers also found that no more than 69 percent of the hospitalized patients received antiviral treatment, partly explained by prescription delays.
Based on the results, the team suggested that “initiatives to increase vaccination uptake and early use of antiviral agents among patients with COPD could reduce influenza-related hospitalization and critical illness and improve healthcare costs in this vulnerable population.”
Mulpuru said, “Our results suggest that greater awareness is needed among patients with COPD and their healthcare providers regarding the severe consequences of influenza infection and the benefits of vaccination. Finding methods to improve vaccination rates among patients with COPD is likely to have a significant impact.”