The association between accelerometer-assessed physical activity and respiratory function in older adults differs between smokers and non-smokers

Archana Singh-Manoux,Vadim Zipunnikov,Séverine Sabia,Mehdi Menai,Mika Kivimäki,Vincent T. van Hees,Jean-Philippe Regnaux,Mohamed Amine Benadjaoud

doi:10.1038/s41598-019-46771-y

Abstract

The association between physical activity and lung function is thought to depend on smoking history but most previous research uses self-reported measures of physical activity. This cross-sectional study investigates whether the association between accelerometer-derived physical activity and lung function in older adults differs by smoking history. The sample comprised 3063 participants (age = 60–83 years) who wore an accelerometer during 9 days and undertook respiratory function tests. Forced vital capacity (FVC) was associated with moderate-to-vigorous physical activity (MVPA; acceleration ≥0.1 g (gravity)) in smokers but not in never smokers: FVC differences for 10 min increase in MVPA were 58.6 (95% Confidence interval: 21.1, 96.1), 27.8 (4.9, 50.7), 16.6 (7.9, 25.4), 2.8 (−5.2, 10.7) ml in current, recent ex-, long-term ex-, and never-smokers, respectively. A similar trend was observed for forced expiratory volume in 1 second. Functional data analysis, a threshold-free approach using the entire accelerometry distribution, showed an association between physical activity and lung function in all smoking groups, with stronger association in current and recent ex-smokers than in long-term ex- and never-smokers; the associations were evident in never smokers only at activity levels above the conventional 0.1 g MVPA threshold. These findings suggest that the association between lung function and physical activity in older adults is more pronounced in smokers than non-smokers.

Highlights

Most studies on the association between physical activity and lung function rely on self-reported physical activity data which are prone to reporting bias
In models adjusted for age, sex, ethnicity, height and weight, compared to never smokers, current, recent, and long-term ex-smokers had respectively 360.0 (95%CI = 254.1, 466.0), 305.6 (95%CI = 221.8, 387.5) and 55.0 (18.5, 91.5) ml lower FEV1, and 278.6 (95%CI = 157.2, 400.0), 238.3 (95%CI = 143.3, 333.2) and 47.6 (95%CI = 5.7, 89.4) ml lower Forced vital capacity (FVC)
Results based on conventional categorization of physical activity showed that the association between moderate-to-vigorous physical activity (MVPA) and lung function is dependent on smoking history, with associations being evident only in current and ex-smokers

Summary

Introduction

Most studies on the association between physical activity and lung function rely on self-reported physical activity data which are prone to reporting bias. Physical activity assessed objectively by accelerometers is more strongly associated with health outcomes[21,22,23]. These studies categorize the duration of physical activities www.nature.com/scientificreports/. Www.nature.com/scientificreports at different intensities (from sedentary behaviour to moderate-and-vigorous physical activity, MVPA) this method represents important loss of information as the physical activity scale is a continuum. To address this issue, functional data analysis is useful in order to model the entire distribution of intensities of accelerometer data[24,25,26].

Methods

Results

Conclusion