COPD Exacerbations Linked to Rising Temperatures

Supaksh Gupta, MD

Research presented at the European Respiratory Society International Congress suggested an increased risk of chronic obstructive pulmonary disease (COPD) exacerbations approximately 2 days after an increase in ambient temperature.

Investigators believed this raised concern regarding increased exacerbation risk with a changing climate.

In an interview with HCPLive, Supaksh Gupta, MD, International Medicine Clinic at Harbourview, Seattle, Washington, spoke of some of the concerns regarding COPD and changing climate.

“Based on prior research, extremes of temperatures (both heat and cold) appear to be associated with increased respiratory mortality in COPD patients as well as heat waves,” Gupta said.

Additionally, COPD exacerbations such as an increase in cough frequency, sputum production, or shortness of breath, had also been recorded.

Prior evidence of respiratory mortality in this vulnerable patient population prompted Gupta and fellow investigators to examine the association between risk of disease exacerbations and ambient temperature in preceding days.

The Study

A time-stratified case-crossover analysis was conducted over the course of the study.

During that time, 1177 current and former smokers from an observational study dubbed SPIROMICS were enrolled in the study. Each participant had at least 1 COPD exacerbation prior to enrollment.

Gupta and colleagues used local ambient temperature as a continuous variable.

Using conditional logistic regression, they assessed the risk of COPD exacerbation based on ambient temperature at lag days 0 to 7.

The Findings

Gupta and investigators noted that risk of exacerbation was elevated for increased temperatures during the preceding 1 to 6 days, with the observed risk peaking at the two-day lag period.

After controlling for relative humidity, each 1-degree Celsius increase in ambient temperature was significantly associated with 2% increased odds of COPD exacerbation 2 days following the elevated temperature (p=0.002).

Gupta noted these findings could possibly be linked to issues regarding the current climate crisis.

“It's difficult to draw a direct link, but it is possible that with the increased wildfire frequency due to the ongoing climate crisis, individuals may be exposed to increased environmental pollutants that have been associated with the risk of development of COPD,” Gupta said.

Gupta hypothesized that access to indoor air conditioning or cooling centers during warm periods might be possible temporizing and protective measures for patients with COPD.

Additionally, he felt as though further research was needed regarding increasing temperatures due to climate issues.

“I’m concerned that with increasing temperatures due to the ongoing climate crisis, the risks of increased morbidity are not equally distributed amongst all patient group,” he said. “Individuals living with COPD may be one such subset of patients at increased risk. Further research is warranted to better characterize the risk and evaluate for protective factors to mitigate that risk.”