Background: While an often clinically reported symptom in hypersensitivity pneumonitis (HP), the burden of cough has yet to be elucidated.

Objective: Examine objective and subjective cough measures in patients with chronic HP, factors associated with cough, and response to treatment.

Methods: We prospectively recruited an observational cohort of patients with HP who were treatment naïve or had a cumulative steroid treatment duration of less than 6 months. Those who underwent bronchoalveolar lavage (BAL) had their lymphocyte fraction recorded. Subjects underwent baseline lung function tests, objective cough monitoring and were asked to complete the cough visual analogue (VAS) and Leicester Cough Questionnaire (LCQ). Patients who received therapy had repeat assessments at 3 months.

Results: 43 patients were recruited (61% female, mean age 64 ± 10.9, mean predicted FVC 85 ± 19.5%, TLco 56 ± 16.7%). Baseline 24hr cough frequency were (n = 26) mean 5.7/hr, median 7.4/hr. Mean values for cough VAS was 35.2 mm, and LCQ was 15.1. These are similar to published data on idiopathic pulmonary fibrosis 1,2. Cough frequency moderately correlated with both VAS (? = 0.67, P <0.001) and LCQ (? = -0.60, P <0.001). BAL lymphocyte fraction (mean 33.6%) was not associated with any of the cough measures. Lower FVC was associated with higher VAS (r = -0.546, P = 0.007). Thirty patients received treatment. At 3 months, Cough VAS reduced (-9.9 mm, P = 0.014) and LCQ improved (1.5 points, P <0.001), but there was no change in 24hr cough frequency (P = 0.64) after treatment.

Conclusions: Cough is a significant problem for patients with HP and current treatment options appear to have limited impact.