Skip to main content

Table 1 The basic characteristics of the subjects

From: Airway oxidative stress in chronic cough

Characteristic Subjects with chronic cough (N = 43) Healthy subjects (N = 15)
Age (years) 55.6 ± 1.9 52.7 ± 4.1
Females – number (%) 32 (74) 11 (73)
Ex smokers – number (%) 20 (47) 4 (27)
Atopic patients – number (%) 14 (33) 1 (7)
Duration of cough (years) 8.5 ± 1.5 ND
Most probable cause of cougha, Rhinitis 22 (51) ND
- number (%) Esophageal reflux 14 (33)  
  Asthma 9 (21)  
Leicester questionnaire total score 13.2 ± 0.5 ND
Cough sensitivity to hypertonic saline (coughs/Osmol/kg) 7.24 ± 1.03 ND
Histamine PD15 (mg)b 1.28 ± 1.20 ND
Nitric oxide concentration (ppm) 16.8 ± 2.0 ND
FEV1 (% of predicted) 93.7 ± 1.8 ND
PEF variation in ambulatory monitoring (%) 7.13 ± 0.68 ND
  1. Continuous data is expressed as means and standard errors. ND = not done; FEV1:= forced expiratory volume in one second; PD15 = provocative dose of histamine to induce a 15% fall in FEV1. PEF = peak expiratory flow.
  2. aBased on the results of the Cough Clinic diagnostic questionnaire. Two patients had more than one most probable cause.
  3. bAmong subjects without a 15% fall in FEV1 in response to histamine, an arbitrary value of 3.2 mg was used as PD15. Histamine challenge was missed in one patient due to technical reasons.