Association between Cough Severity and Quality of Life Depends on Sex among Patients with Postinfectious Cough

Abstract Background: Sex difference in quality of life (QoL) and association between cough severity and QoL for subacute cough remains unknown. This study aimed to investigate whether there was sex difference in quality of life, and whether association between cough severity and QoL was modified by sex. Methods: Secondary analyses were performed in 180 participants with postinfectious cough in a multisite randomized controlled trial. Baseline demographics, clinical characteristics and cough specific quality of life questionnaire (CQLQ) were collected. Linear regression analyses were conducted to examine sex difference in CQLQ. Associations between cough severity, cough treatment and CQLQ in different sex were also analyzed. Results: The differences between women and men were not significant in the total CQLQ in the unadjusted analysis (P = 0.077). Women had 2.20-point higher total CQLQ score than men (0.11 to 4.30, P = 0.039), after adjusting for age, cough duration, cough severity, and clinical center. An increase of 1-point in cough severity was associated with a 2.55-point (1.16 to 3.95) increase in total CQLQ in women versus a 1.26-point (0.20 to 2.31) increase in men (P = 0.020). Sex did not modify treatment benefit in total CQLQ in both unadjusted and adjusted analyses (P = 0.287 and P = 0.819, respectively). Conclusions: Women may be associated with worse quality of life than men, and women’s quality of life is more significantly impaired as cough severity increases. However, they may have similar treatment response in QoL improvement.Trial registration: Chinese Clinical Trial Registry, ChiCTRTRC12002297. Registered 19 June 2012, http://www.chictr.org.cn/abouten.aspx