Poor asthma control may reduce a patient’s overall daily activity. Little is known about productivity limitations in patients with well- vs poorly-controlled asthma. We compared overall daily activity impairment in well-controlled vs poorly-controlled asthma patients enrolled in a longitudinal observational cohort study.
Methods: EXCELS was a 5-year prospective observational cohort study of ~5000 omalizumab (OMA)-treated and 2500 non-OMA-treated moderate-to-severe persistent allergic asthma patients, aged ≥ 12 years. Patients reported asthma control via the Asthma Control Test (ACT; well-controlled [ACT>19] vs poorly-controlled [ACT≤19]) and productivity impairment via the Work Productivity and Activity Impairment-Asthma (WPAI-A) questionnaires at baseline, every 6 months through Month 24, and then yearly. WPAI-A ratings were summarized as the percent activity impairment due to asthma. Higher ACT scores reflect better asthma control, and higher WPAI numbers reflect greater productivity loss. We calculated the Pearson correlation coefficients between WPAI and ACT scores.
Well-controlled asthma patients consistently reported less productivity impairment (mean WPAI-A scores [SD; n]) than those with poorly-controlled asthma: baseline (6.9 [12.5, n=3429] vs 37.4 [28.6, n=3902], p<0.001), year (Y)1 (6.4 [12.1, n=3953] vs 37.7 [27.8, n=3378] p<0.001), Y2 (6.3 [11.9, n=4019] vs 37.7 [27.4, n=3312] p<0.001), and Y3 (6.3 [12.0, n=4050] vs 38.2 [27.5, n=3281] p<0.001). Similar results were obtained when patients were stratified by their omalizumab status (continuous users, new starts, and no-users). ACT/WPAI correlation varied between -0.707 and -0.750 across timepoints.
Asthma control demonstrated strong negative correlation with work/school productivity impairment: poor asthma control was consistently associated with higher productivity impairment.