Predictors for change in cough-related quality of life and symptom severity in acute cough: results of an observational pharmacy-based study.

Background: Acute cough is a common symptom, frequently linked to respiratory tract infections. Although self-limiting, acute cough can significantly affect patients' quality of life (QoL), causing discomfort, disrupting sleep, and hindering daily activities. Identifying factors contributing to changes in cough-related QoL (crQoL) and severity of symptoms (SoS) is essential for developing personalised treatment approaches and enhancing patient care. The aim of this study was to investigate predictors for change in crQoL and SoS in individuals with acute cough due to respiratory tract infections using the thyme/ivy herbal fluid extract BNO 1200 (Bronchipret^® drops).

Methods: We retrospectively analysed data from an observational/non-interventional pharmacy-based study on the effectiveness and tolerability of BNO 1200 for the treatment of acute cough due to respiratory tract infections. CrQoL and SoS were measured with the Leicester Cough Questionnaire (LCQ) and a patient-adapted version of the Bronchitis Severity Score (BSS), respectively. Change was defined as differences of LCQ and BSS scores before and after treatment with BNO 1200. We included age, sex, smoking status, cough severity and duration of symptoms before taking BNO 1200 as predictors for change in crQoL and SoS in multivariable regression analyses. Regarding clinically meaningful crQoL improvement (LCQ differences of ≥2 points), logistic regression analysis was performed, respectively. We derived β-estimates or odds ratios (ORs) with 95% confidence interval (CI).

Results: Data from 674 participants (mean age 44.7 years, 66.2% female) with acute cough due to respiratory tract infections were analysed. LCQ and BSS scores showed a mean change of 6.3 points (95% CI: 6.0 to 6.5) and 6.2 points (95% CI: 5.9 to 6.5) from baseline to follow-up, respectively. Further, 615 participants (91.2%) showed an improvement in LCQ scores of ≥2 points. Analyses on predictors for change in crQoL revealed that lower crQoL prior to treatment and longer duration of intake of BNO 1200 were significantly associated with crQoL change. When clinically meaningful crQoL improvement was considered, greater cough severity prior to treatment and lower crQoL before treatment were statistically significant predictors. Regarding SoS, crQoL prior to treatment (LCQ baseline values), longer duration of intake of BNO 1200, greater symptom severity prior to treatment (BSS baseline values) and younger age were significantly associated with greater change.

Conclusions: Factors predicting change in crQoL and SoS in acute cough due to respiratory tract infections were mainly at the level of symptom severity, treatment duration and crQoL prior to treatment with BNO 1200.