BMJ Open Respiratory Research (Sep 2020)
Asthma control is associated with economic outcomes, work productivity and health-related quality of life in patients with asthma
Abstract
Background The objective of this analysis was to examine the association between asthma control (based on Asthma Control Test (ACT) responses) and healthcare resource utilisation (HRU), work productivity and health-related quality of life (HRQoL) among a nationwide sample of US adults with a self-reported diagnosis of asthma and without comorbid chronic obstructive pulmonary disease.Methods Data were obtained from the 2015 and 2016 self-administered, internet-based National Health and Wellness Surveys. Patients were grouped by ACT score (≤15: poorly controlled; 16–19: partly controlled; 20–25: well-controlled asthma). Study outcomes included HRU (patient-reported healthcare provider visits, emergency department visits and hospitalisations during the previous 6 months); work productivity, measured using the Work Productivity and Activity Impairment-General Health Scale; HRU-associated costs and work productivity loss and HRQoL, measured using EuroQoL-5 Dimensions-5 Levels (EQ-5D-5L) and the Short Form Health Survey-36V.2 (SF-36V.2). Incremental differences in outcomes between groups were assessed using generalised linear models adjusted for covariates.Results Of 7820 eligible adults, 17.4% had poorly controlled, 20.1% partly controlled and 62.5% well-controlled asthma. Well-controlled asthma was associated with significantly lower HRU (p<0.001) and lower mean direct costs ($6012 vs $8554 and $15 262, respectively; p<0.001); well-controlled asthma was also associated with significantly lower mean scores for work absenteeism, work presenteeism, overall work impairment and activity impairment (all p<0.001), and lower mean indirect costs ($6353 vs $10 448 and $14 764, respectively; p<0.001). Clinically meaningful differences favouring well-controlled asthma were seen for all HRQoL measures, with statistically significantly higher adjusted mean EQ-5D-5L index and SF-6D Health Utilities Index scores (derived from SF-36V.2) for patients with well-controlled asthma compared with partly controlled or poorly controlled asthma (p<0.001).Conclusions The study demonstrates a clear relationship between asthma control and its impact on HRU, costs, work productivity and HRQoL. This will allow for better identification and management of patients with poorly controlled asthma.