Physical activity and influenza-coded outpatient visits, a population-based cohort study

Role of Physical Activity in the Prevention and Treatment of Influenza: A Review

BACKGROUND

Many concerns regarding respiratory diseases, including influenza, emerged during the epidemic of COVID-19. There were relevant research findings and suggestions for influenza prevention and treatment through physical activity, but little report about the total efficiency. So, this review was to summarize the role of physical activity in influenza prevention and treatment.

MAIN BODY

The databases Web of Science, Google Scholar, EBSCO, PubMed, CNKI, and Science Direct were used to search the related literatures. The first search ran from July to October, 2021, and the second search was conducted in September, 2023. Those publications that reported the effects of physical activity, exercise, and sport on influenza, flu, and cold were included. It found that long-term adherence to moderate physical activity is beneficial in enhancing the body's ability to resist influenza viruses. However, high-intensity endurance physical activity can cause an open window in the human immune system, which increases the risk of infection by influenza viruses. The patients with influenza infections can participate in moderate physical activity during the pre-onset period, but some of the researchers do not recommend physical activity for patients with influenza, avoiding the transmission of influenza viruses to others through human contact of physical activity. Moreover, animal studies have shown that physical activity may worsen influenza disease. While studies found that moderate physical activity is beneficial for preventing influenza, as most experimental studies were conducted on animals, the mechanisms in human with physical activity are still unclear. No study has yet suggested exercise prescriptions to prevent and control influenza, and there is currently no way to prevent or control influenza just through physical activity. The follow-up research is needed to increase human clinical experiments, elucidate the effect of physical activity on influenza, develop exercise prescriptions and gradually promote physical activity as a practical means for preventing and treating influenza.

SHORT CONCLUSIONS

Overall, participating in moderate physical activity regularly should be beneficial in influenza prevention, alleviating the patients' symptoms and increasing the recovery efficiency, but this needs more testing in clinical human trials.

Leisure Time Physical Activity and SARS-CoV-2 Infection among ELSA-Brasil Participants

The regular practice of physical activity (PA) can reduce the chance of aggravation of the disease and lower rates of hospitalization and mortality from COVID-19, but few studies have analyzed the association of PA with the risk of infection by SARS-CoV-2. The aim of the study was to analyze the association between PA and self-reported SARS-CoV-2 infection. A longitudinal study was conducted with data from 4476 ELSA-Brasil participants who had their PA analyzed twice, once in 2016-2018 and again in 2020. PA was identified using the IPAQ at both follow-up moments and categorized into four groups: (a) remained physically inactive (reference); (b) remained physically active; (c) became physically active in the second moment; and (d) became physically inactive in the second moment. The variables of age, sex, obesity, hypertension, diabetes and specific protective practices against COVID-19 were tested as possible confounders. Data were analyzed by logistic regression. A 95% confidence interval (CI) was used. Remaining physically active was associated with a 43% reduction in the risk of SARS-CoV-2 infection only among those who used specific practices to protect against COVID-19, OR = 0.57 and CI = 0.32-0.99. The results suggested that regular practice of PA can reduce the risk of SARS-CoV-2 infection, especially among those who have used specific practices to protect against COVID-19 during the pandemic.

The influence of physical activity level on the length of stay in hospital in older men survivors of COVID-19

The purpose of this study was to verify the influence of physical activity level on the length of hospital stay in older men recovered from COVID-19. In total, 126 older men diagnosed with COVID-19 were admitted to the hospital between September and December 2020. Among them, 70 survived, of which 39 older men were included in the study. Within 30 days after discharge, patients answered the International Physical Activity Questionnaire to measure their physical activity level through phone contact, with questions corresponding to the week before symptom onset. Clinical and laboratorial data from admission, days between onset of symptoms and admission, length of stay, computed tomography abnormalities, and the need for the intensive care unit were collected. The groups (active × sedentary) were compared using the Student t test or Mann-Whitney test for quantitative data and chi-square test was used for categorical data. There is no difference between the groups in characteristics of admission (p > 0.05), except by potassium level. Active older men had a shorter length of stay (6.50 ± 3.46 vs 11.48 ± 7.63 days; p = 0.03), disease duration (15.71 ± 4.84 vs 21.09 ± 7.69 days; p = 0.02), and lower frequency of lung damage when compared to their sedentary counterparts. In conclusion, being physically active prior to infection can attenuate length of hospital stay in older men with COVID-19.

Associations between physical activity prior to infection and COVID-19 disease severity and symptoms: results from the prospective Predi-COVID cohort study

OBJECTIVE

To investigate if the physical activity (PA) prior to infection is associated with the severity of the disease in patients positively tested for COVID-19, as well as with the most common symptoms.

DESIGN

A cross-sectional study using baseline data from a prospective, hybrid cohort study (Predi-COVID) in Luxembourg. Data were collected from May 2020 to June 2021.

SETTING

Real-life setting (at home) and hospitalised patients.

PARTICIPANTS

All volunteers aged >18 years with confirmed SARS-CoV-2 infection, as determined by reverse transcription-PCR, and having completed the PA questionnaire (n=452).

PRIMARY AND SECONDARY OUTCOME MEASURES

The primary outcome was disease severity (asymptomatic, mild illness and moderate illness). The secondary outcomes were self-reported symptoms.

RESULTS

From the 452 patients included, 216 (48%) were female, the median (IQR) age was 42 (31-51) years, 59 (13%) were classified as asymptomatic, 287 (63%) as mild illness and 106 (24%) as moderate illness. The most prevalent symptoms were fatigue (n=294; 65%), headache (n=281; 62%) and dry cough (n=241; 53%). After adjustment, the highest PA level was associated with a lower risk of moderate illness (OR 0.37; 95% CI 0.14 to 0.98, p=0.045), fatigue (OR 0.54; 95% CI 0.30 to 0.97, p=0.040), dry cough (OR 0.55; 95% CI 0.32 to 0.96, p=0.034) and chest pain (OR 0.32; 95% CI 0.14 to 0.77, p=0.010).

CONCLUSIONS

PA before COVID-19 infection was associated with a reduced risk of moderate illness severity and a reduced risk of experiencing fatigue, dry cough and chest pain, suggesting that engaging in PA may be an effective approach to minimise the severity of COVID-19.

TRIAL REGISTRATION NUMBER

NCT04380987.

Association between physical activity and immunogenicity of an inactivated virus vaccine against SARS-CoV-2 in patients with autoimmune rheumatic diseases

OBJECTIVES

To investigate whether physical activity is associated with enhanced immunogenicity of a SARS-CoV-2 inactivated vaccine (Coronavac) in patients with autoimmune rheumatic diseases (ARD) (n = 898) and in non-ARD (n = 197) individuals without pre-existing immunogenicity to SARS-CoV-2.

METHODS

This was a prospective cohort study within an open-label, single-arm, phase 4 vaccination trial. Immunogenicity was assessed after vaccination by measuring seroconversion rates of total anti-SARS-CoV-2 S1/S2 IgG (SC), geometric mean titers of anti-S1/S2 IgG (GMT), factor-increase in GMT (FI-GMT), frequency of neutralizing antibody (NAb), and median neutralizing activity. Physical activity (active being defined as ≥ 150 min/week) and sedentary behavior (>8h/day) were assessed by questionnaire.

RESULTS

Physically active ARD patients (n = 494) were younger and less frequently used prednisone/biologics than inactive patients (n = 404). After controlling for covariates, active patients exhibited greater SC (OR: 1.4 [95%CI: 1.1-2.0]), GMT (32% [95%CI: 8.8-60) and FI-GMT (33% [95%CI: 9.6-63%]) vs. inactive. Cluster analysis (physical activity/sedentary status) revealed greater GMT (43.0% [95% CI: 11.0-84.0%) and FI-GMT (48.0% [95%CI: 14.0-92.0%]) in active/non-sedentary vs. inactive/sedentary ARD patients. A dose-response was observed, with greater benefits for the group of patients performing ≥ 350 min/week of physical activity (OR: 1.6 [95%CI: 1.1-2.4]; 41% [95%CI: 10-80%]; 35% [95%CI: 4.3-74], for SC, GMT, and FI-GMT, respectively) vs. the least active group (≤30 min/week). Greater SC (OR: 9.9 [95%CI: 1.1-89.0]) and GMT (26% [95%CI: 2.2-56.0%]) were observed in active vs. inactive non-ARD.

CONCLUSIONS

A physically active lifestyle may enhance SARS-CoV-2 vaccine immunogenicity, a finding of particular clinical relevance for immunocompromised patients.

TRIAL REGISTRATION

Clinicaltrials.gov #NCT04754698.

Association of Physical Activity and Lower Respiratory Tract Infection Outcomes in Patients With Cardiovascular Disease

Background To investigate the dose-response association between physical activity and lower respiratory tract infection (LoRI) outcomes in patients with cardiovascular disease. Methods and Results Using the Korean National Health Insurance data, we identified individuals aged 18 to 99 years (mean age, 62.6±11.3 years; women, 49.6%) with cardiovascular disease who participated in health screening from January 1, 2009, to December 31, 2012 (n=1 048 502), and were followed up until 2018 for mortality and until 2019 for hospitalization. Amount of physical activity was assessed using self-reported questionnaires and categorized into 5 groups: 0 (completely sedentary), <500, 500 to 999, 1000 to 1499, and ≥1500 metabolic equivalents of task min/wk. After controlling for various confounders, adjusted hazard ratios (95% CIs) were 1.00 (reference), 0.74 (0.70-0.78), 0.66 (0.62-0.70), 0.52 (0.47-0.57), and 0.54 (0.49-0.60) for LoRI mortality, and 1.00 (reference), 0.84 (0.83-0.85), 0.77 (0.76-0.79), 0.72 (0.70-0.73), and 0.71 (0.69-0.73) for LoRI hospitalization among those engaging in physical activity of 0, <500, 500 to 999, 1000 to 1499, and ≥1500 metabolic equivalents of task min/wk, respectively. Assuming linear association between 0 and 2000 metabolic equivalents of task min/wk, each 500-metabolic equivalents of task min/wk increase of physical activity was associated with reduced LoRI mortality and hospitalization by 22% and 13%, respectively. The negative association was stronger in the older population than in the younger population (P for interaction <0.01). Conclusions In patients with cardiovascular disease, engaging in even a low level of physical activity was associated with a decreased risk of mortality and hospitalization from LoRI than being completely sedentary, and incremental risk reduction was observed with increased physical activity.

Estimating the Risk of Influenza-Like Illness Transmission Through Social Contacts: Web-Based Participatory Cohort Study

Background

Epidemiological studies on influenza have focused mostly on enhancing vaccination coverage or promoting personal hygiene behavior. Few studies have investigated potential effects of personal health behaviors and social contacts on the risk of getting influenza-like illness (ILI).

Objective

Taking advantage of an online participatory cohort, this study aimed to estimate the increased risk of getting ILI after contact with infected persons and examine how personal health behaviors, weather, and air pollution affect the probability of getting ILI.

Methods

A Web-based platform was designed for participants to record daily health behaviors and social contacts during the influenza season of October 1, 2015 to March 31, 2016, in Taiwan. Data on sleep, diet, physical activity, self-reported ILI, and contact with infected persons were retrieved from the diaries. Measurements of weather and air pollutants were used for calculating environmental exposure levels for the participants. We fitted a mixed-effects logistic regression model to the daily measurements of the diary keepers to estimate the effects of these variables on the risk of getting ILI.

Results

During the influenza season, 160 participants provided 14,317 health diaries and recorded 124,222 face-to-face contacts. The model estimated odds ratio of getting ILI was 1.87 (95% CI 1.40-2.50) when a person had contact with others having ILI in the previous 3 days. Longer duration of physical exercise and eating more fruits, beans, and dairy products were associated with lower risk of getting ILI. However, staying up late was linked to an elevated risk of getting ILI. Higher variation of ambient temperature and worse air quality were associated with increased risk of developing ILI.

Conclusions

Developing a healthier lifestyle, avoiding contact with persons having ILI symptoms, and staying alert with respect to temperature changes and air quality can reduce the risk of getting ILI.

Social participation and risk of influenza infection in older adults: a cross-sectional study

OBJECTIVES

Influenza infection can cause severe pneumonia, which is sometimes fatal, particularly in older adults. Influenza results in 3-5 million cases of severe illness and about 250 000 to 500 000 deaths annually worldwide. Social participation in the context of influenza infection is controversial because, although social participation is beneficial in maintaining physical function and mental health, it also increases the risk of contact with infected people. This study examined the association between social participation and influenza infection in Japanese adults aged 65 years or older.

DESIGN

Cross-sectional study.

SETTING

Japanese functionally independent adults aged 65 years or older.

PARTICIPANTS

Among the respondents to the Japan Gerontological Evaluation Study (JAGES) 2013 survey, which took place during the period from October to December 2013, 12 231 men and 14 091 women responded to questions on influenza vaccination and influenza infection.

OUTCOME MEASURES

Using JAGES data for 12 231 men and 14 091 women aged ≥65 years, we examined the association between social participation and influenza infection. The association between influenza infection and number of groups in which respondents participated was investigated among adults aged≥65 years, stratified by vaccination status and sex.

RESULTS

Unvaccinated women who participated in two or more social activities were 2.20 times (95% CI 1.47 to 3.29) as likely to report an influenza infection as those who reported no social participation. In contrast, vaccinated women who participated in two or more social groups had no additional risk of influenza infection as compared with female elders with no social participation. Among men, participation in social activities was not significantly associated with influenza infection, regardless of vaccination status.

CONCLUSIONS

Social participation was associated with a higher risk of influenza infection among unvaccinated older women, which suggests a need for further efforts to promote influenza vaccination, particularly among socially active elderly women.

Effects of exercise on vaccine-induced immune responses

The role of exercise in health is well known; here we discuss the specific role of exercise in vaccination responses. Chronic exercise or high levels of physical activity have been shown to be related to improved vaccination responses in older adults, illustrating improved immune function, and conferring potentially significant public health benefit. Acute exercise has recently been examined as a potential adjuvant to vaccination; its promise for clinical use warrants further investigation, given current data.