A population-based cohort of adults with asthma: mortality and participation in a long-term follow-up

Helena Backman,Linnea Hedman,Caroline Stridsman,Sven-Arne Jansson,Anne Lindberg,Bo Lundbäck,Eva Rönmark

doi:10.1080/20018525.2017.1334508

Abstract

ABSTRACT Background and objective: Asthma is a major public health concern. The aim of this study was to characterize a large population-based cohort of adults with asthma, and to study factors associated with all-cause mortality and non-participation in a long-term follow-up. Design: Random and stratified samples from five population-based cohorts were clinically examined during 1986–2001, and all subjects with asthma were included in the study (n = 2055, age 19–72 years, 55% women). Independent associations between different risk factors and (i) mortality and (ii) non-participation in a clinical follow-up in 2012–2014 were estimated. Results: In 1986–2001, 95% reported any wheeze and/or attacks of shortness of breath in the past 12 months, and/or asthma medication use. Over the up to 28 years of follow-up time, the cumulative mortality was 22.7%. Male gender, current smoking, and lower forced expiratory volume in 1 sec of predicted (FEV1% of predicted) were independent risk factors for mortality, while obesity was associated with non-participation in the follow-up. Older ages, ischemic heart disease, and low socioeconomic status were associated with both mortality and non-participation. Conclusions: The risk factors associated with mortality in this adult population-based asthma cohort were similar to those commonly identified in general population samples, i.e. male gender, current smoking, and lower FEV1% of predicted, while obesity was associated with non-participation in a long-term follow-up. Ischemic heart disease, low socioeconomic status, and older ages were associated with both mortality and non-participation.

Highlights

Asthma is a major public health concern which places a considerable burden on society in terms of morbidity, mortality, and costs [1]
Subjects with asthma have long been reported to have excess all-cause mortality compared to subjects without asthma [11,12,13], the excess mortality among subjects with asthma seems to be declining, according to recent studies [14,15,16,17]. This excess mortality risk is related to lower pre-bronchodilator forced expiratory volume in 1 sec (FEV1) [12,18,19,20,21] and large FEV1 bronchodilation response [22], but studies presenting factors associated with mortality among subjects with asthma are scarce
The main findings were that male gender, current smoking, older age, lower FEV1% of predicted, and ischemic heart disease at study entry were independent risk factors for mortality among adult subjects with asthma followed over 10–28 years

Summary

Introduction

Asthma is a major public health concern which places a considerable burden on society in terms of morbidity, mortality, and costs [1] It is a common disease of differing severity presenting with several phenotypes [2]. The aim of this study was to characterize a large population-based cohort of adults with asthma, and to study factors associated with all-cause mortality and non-participation in a long-term follow-up. Current smoking, and lower forced expiratory volume in 1 sec of predicted (FEV1% of predicted) were independent risk factors for mortality, while obesity was associated with non-participation in the follow-up. Conclusions: The risk factors associated with mortality in this adult population-based asthma cohort were similar to those commonly identified in general population samples, i.e. male gender, current smoking, and lower FEV1% of predicted, while obesity was associated with non-participation in a long-term follow-up. Low socioeconomic status, and older ages were associated with both mortality and non-participation

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Methods

Results

Conclusion