Meditation or Exercise for Preventing Acute Respiratory Infection - A Randomized Controlled Trial

Bruce Barrett, MD, PhD, Mary S. Hayney, PharmD, Daniel Muller, MD, PhD, David Rakel, MD, Ann Ward, PhD, Chidi N. Obasi, MD, Roger Brown, PhD, Zhengjun Zhang, PhD, Aleksandra Zgierska, MD, PhD, James Gern, MD, Rebecca West, PhD, APRN, Tola Ewers, MS, Shari Barlow, BA, Michele Gassman, MA, Christopher L. Coe, PhD

Ann Fam Med. 2012;10(4):337-346.

Abstract and Introduction

Abstract

Purpose This study was designed to evaluate potential preventive effects of meditation or exercise on incidence, duration, and severity of acute respiratory infection (ARI) illness.

Methods Community-recruited adults aged 50 years and older were randomized to 1 of 3 study groups: 8-week training in mindfulness meditation, matched 8-week training in moderate-intensity sustained exercise, or observational control. The primary outcome was area-under-the-curve global illness severity during a single cold and influenza season, using the Wisconsin Upper Respiratory Symptom Survey (WURSS-24) to assess severity. Health care visits and days of missed work were counted. Nasal wash collected during ARI illness was assayed for neutrophils, interleukin-8, and viral nucleic acid.

Results Of 154 adults randomized into the study, 149 completed the trial (82% female, 94% white, mean age 59.3 ± 6.6 years). There were 27 ARI episodes and 257 days of ARI illness in the meditation group (n = 51), 26 episodes and 241 illness days in the exercise group (n = 47), and 40 episodes and 453 days in the control group (n = 51). Mean global severity was 144 for meditation, 248 for exercise, and 358 for control. Compared with control, global severity was significantly lower for meditation (P = .004). Both global severity and total days of illness (duration) trended toward being lower for the exercise group (P=.16 and P=.032, respectively), as did illness duration for the meditation group (P=.034). Adjusting for covariates using zero-inflated multivariate regression models gave similar results. There were 67 ARI-related days of-work missed in the control group, 32 in the exercise group (P = .041), and 16 in the meditation group (P <.001). Health care visits did not differ significantly. Viruses were identified in 54% of samples from meditation, 42% from exercise, and 54% from control groups. Neutrophil count and interleukin-8 levels were similar among intervention groups.

Conclusions Training in meditation or exercise may be effective in reducing ARI illness burden.

Introduction

Acute respiratory infection (ARI) is extremely common, often debilitating, and among the most costly of human illnesses. Influenza, the most serious of the viral ARIs, is associated with approximately 36,000 deaths and more than 500,000 hospitalizations in the United States yearly.^[1] Nevertheless, symptoms of influenza infection are usually indistinguishable from those produced by other viruses.^[2,3] In the United States each year, noninfluenza ARI accounts for more than 20 million doctor visits and 40 million lost school and work days, with an economic impact of more than $40 billion, making noninfluenza ARI rank first in the top 10 most expensive illnesses.^[4] Reducing this burden even modestly could lead to substantial economic and quality-of-life benefits.
Available treatments are not very effective. If started early enough, antiviral medications have limited efficacy for influenza,^[5] but not for other viral ARIs. Symptomatic treatments may reduce severity slightly but have never been shown to reduce illness duration or overall severity. Influenza vaccination is accepted as effective for prevention,^[6] but it is imperfect, with sero-protection rates ranging from 60% to 80% in healthy younger adults and 40% to 60% in the elderly.^[7] For noninfluenza ARI, immunization strategies are impractical, and preventive strategies are limited to not smoking,^[8] hand washing,^[9] and avoiding sick contacts.
There is some evidence that enhancing general physical and mental health may reduce ARI burden. In a series of observational and viral inoculation studies, perceived stress,^[10] negative emotion,^[11] and lack of social support^[12] predicted not only self-reported illness, but also such biomarkers as viral shedding and inflammatory cytokine activity. Evidence suggests that mindfulness meditation can reduce experienced stress and negative emotions.^[13,14] Similarly, both epidemiological and experimental studies have suggested that regular exercise may protect people from ARI illness.^[15,16] A recent observational cohort study (n = 1,002 adults) reported 32% to 46% lower incidence, duration, and severity of ARI illness among the most active vs least active participants.^[17] Thus, sufficient evidence exists to justify testing the hypothesis that training in meditation or exercise can reduce susceptibility to ARI illness.