For patients with chronic obstructive pulmonary disease (COPD), catching a cold can be more than just an annoyance; their risk of experiencing COPD symptom exacerbation rises 30-fold when they exhibit signs of a cold.
Researchers in Canada conducted an observational study in which patients with varying COPD severity were asked to report both their respiratory symptoms and cold incidence daily, then examined the relationship between the 2 factors. Their findings were published
in the International Journal of Chronic Obstructive Pulmonary Disease.
In the study, some participants were given a fax machine while others were provided with a smartphone. Both groups were asked to use the given device to complete a “diary” of respiratory and cold-like symptoms every day. The diary questions asked about respiratory symptoms including shortness of breath, cough, and phlegm, while colds were determined by reports of 2 or more consecutive days of symptoms like runny/stuffy nose, sore throat, or chest congestion. If a cold was detected, a nurse would visit the patient’s house to collect samples for detection of a respiratory virus.
As the researchers had predicted, there was a significant correlation between cold symptoms and COPD exacerbations. Among patients who had experienced at least 1 exacerbation, 1 cold, and 1 cold-free period, the relative risk of exacerbation was 30.4 times higher when they had a cold compared with when they did not. Of the 262 COPD exacerbations observed in the study, 217 began when cold-like symptoms were present for at least 1 day.
When scoring the severity of COPD symptom exacerbation, the researchers found that symptom scores were significantly higher in patients who were positive for both a cold and virus, in those cold negative but virus positive, and in those cold positive but virus negative, compared with exacerbations that were negative for both cold and virus. The mean symptom severity score was highest during the first 3 days of cold symptoms, though the scores were also elevated in the intermediate and late stages of a cold compared with when no cold was present.
Based on the findings that “the presence of apparent colds in COPD patients is associated with both increased risk of exacerbations and greater severity of these when they occur,” the study authors emphasized the importance of avoiding exposure to colds and infections. They referenced the growing burden of COPD in both healthcare costs and mortality, which makes it all the more essential to prevent symptom exacerbations whenever possible.
“The benefit of ensuring that COPD patients receive annual influenza immunization is obvious, as are basic hygiene procedures,” they wrote. Cold-like symptoms, “when detected and reported by COPD patients, should initiate watchfulness on the part of health care providers to reduce the possibility of major intervention being required.”