Meeting physical activity guidelines halves mortality risk due to flu, pneumonia

Key takeaways:

• Achieving even 10 to 150 minutes of aerobic physical activity a week may have mortality benefits.
• Conversely, high levels of muscle strengthening a week increased the risk for influenza and pneumonia mortality.

Adults who met the minimum recommended amount of weekly aerobic and muscle-strengthening activities had a 48% lower risk for influenza and pneumonia compared with those not meeting the guidelines, according to researchers.

"We were impressed during the pandemic by the many studies showing that regular physical activity reduced the risk of severe COVID-19 illness,” Bryant J. Webber, MD, MPH, of CDC’s division of nutrition, physical activity and obesity, told Healio. “We were also aware of other studies showing the benefit of physical activity for preventing other infectious disease outcomes. In light of this, we wished to analyze the association between physical activity and influenza and pneumonia mortality using a large dataset of American adults.”

The study, published in the British Journal of Sports Medicine, examined the association in 577,909 U.S. adults who participated in the National Health Interview Survey from 1998 to 2018.

The participants were considered to have met both aerobic guidelines if they reported 150 minutes or more of moderate-to-vigorous physical activity (MVPA) per week and two or more episodes of muscle-strengthening activities (MSAs) per week.

Compared with participants who met neither guideline, Webber and colleagues found that participants who met both recommendations had a 48% lower adjusted risk for influenza and pneumonia mortality (HR = 0.52; 95%CI, 0.39-0.68).

Those who only met the MVPA guidelines had a 36% lower adjusted risk for mortality related to both diseases (HR = 0.64; 95%CI, 0.54-0.76), and there was no significant association for participants who only met the MSA guideline.

After adjusting for MSA, sociodemographic and lifestyle factors, underlying medical conditions and vaccination status, participants who reported MVPA vs. those who reported no activity had a:

• 21% lower risk for mortality with 10 to 149 minutes of weekly activity;
• 41% lower risk for mortality with 150 to 300 minutes of weekly activity;
• 50% lower risk for mortality with 301 to 600 minutes of weekly activity; and
• 41% lower risk for mortality with more than 600 minutes of weekly activity.

Meanwhile, after adjusting for aerobic activity, Webber and colleagues found that two or more episodes of MSA per week was associated with a 47% lower risk for mortality compared with fewer than two episodes per week.

“Interestingly, risk was 41% higher among adults reporting very high levels of muscle-strengthening activity (seven episodes/week or more),” Webber said.

The researchers highlighted the significant difference in mortality risk for participants who had 10 to 150 minutes of MVPA vs. those who reported no MVPA.

“Although this level is often labelled ‘insufficient’ because it falls below the recommended duration, it may confer health benefits relative to physical inactivity,” they wrote.

Webber said that primary care physicians should consider physical activity “as another tool — in addition to influenza and pneumococcal vaccination — for preventing death from influenza and pneumonia.”

“When counseling patients, PCPs might mention that physical activity has a broad range of health benefits, including immediate benefits for sleep, blood pressure and anxiety levels, and long-term benefits for brain health, chronic disease prevention, healthy weight management and, as demonstrated in this study and others, infectious disease mortality protection,” he said.

Webber added that PCPs should also consider adding physical activity “as a ‘vital sign’ that is routinely assessed and documented during patient encounters.”

“As we note briefly in the paper, clinical decision tools that flag inadequate levels of physical activity, and potentially flag very high levels of muscle-strengthening activity, might help identify patients who would benefit from physical activity counseling,” he said.