麻豆传媒

HONOLULU -- Exposure to colder temperatures, especially those below 20°F, was associated with an increased risk for chronic obstructive pulmonary disease (COPD) exacerbations leading to hospitalizations in older adults, an analysis of 2007-2019 Medicare data showed.

From November to February, there was a 1.5- to 2-fold increase in hospitalizations for Medicare beneficiaries with COPD, reported Ashwaghosha Parthasarathi, MBBS, of Rutgers University in New Jersey, during the CHEST annual meeting hosted by the American College of Chest Physicians.

In December to January, risk for COPD exacerbations leading to hospitalizations increased with decreasing temperatures:

• 65 to 79°F: OR 1.00
• 20 to 65°F: OR 1.13
• 15 to 20°F: OR 1.21
• -42 to 15°F: OR 1.26

Parthasarathi explained that climate change is a driving factor for not only more frequent extreme temperatures, but for more instances of cold weather throughout the country, which may lead to an increase in COPD exacerbations.

"What happens with climate change is polar vortex destabilization, [which could] cause excess extreme cold snaps in the continental U.S. What that means is we are now experiencing, even if it is for shorter durations, harsher winters compared to the previous years," he said.

He told 麻豆传媒 that, even in the South, they saw the same trend.

COPD is the fourth leading cause of death in the U.S., with more than 30 million people projected to have COPD by 2050. Older patients in particular are more prone to developing the disease, due to age-related changes in the lungs, more comorbidities, and impaired immunity.

For this study, a 3% random sample of Medicare patients from 2007 to 2019 was linked, through zip code, with daily national temperature data from the Parameter-elevation Relationships on Independent Slopes Model (PRISM) model. COPD hospitalization was defined as either inpatient or emergency department visits with a primary ICD-9 or -10 code for COPD.

Up to five controls were sampled on the same day of the week up to five weeks from the case date.

There were 158,515 patients with COPD hospitalization included; 47% were ages 65-74, and 40% were 75-84. Most patients were women (61%) and white (88%).

Common comorbidities among patients included hypertension, hyperlipidemia, diabetes mellitus, heart failure, pneumonia, anxiety, asthma, and depression.

Of these patients, 41% lived in the South, 24% in the Midwest, 21% in the Northeast, and 14% in the West.

The study's findings may prove useful for both interventions and resource planning to ensure that the healthcare system is able to meet the challenges of climate change, Parthasarathi said.

He noted that zip code-level exposure did not necessarily correlate with individual cold exposure, which was a limitation to the study. Furthermore, the study did not account for air pollution, humidity, and green spaces, potentially limiting its findings.

Further study is underway, and is aiming to examine larger population samples.

Comment