Skip to main content

Table 5 Features of differences between cough intensity and frequency

From: Clinical significance of self-reported cough intensity and frequency in patients with interstitial lung disease: a cross-sectional study

 

Cough frequency-dominant group

Equal cough severity group

Cough intensity-dominant group

p-value

(n = 12)

(n = 79)

(n = 38)

Type of interstitial lung disease, n (%)

0.858

 IIPs

7 (58)

41 (52)

22 (58)

 

 CTD-ILD

5 (42)

30 (38)

14 (37)

 

 CHP

0

8 (10)

2 (5)

 

Age, years, median (IQR)

73 (67–79)

70 (65–75)

65 (59–74)

0.048

Male sex, n (%)

7 (58)

47 (56)

22 (58)

0.986

Current smoker, n (%)

3 (25)

4 (5)

3 (8)

0.091

Pack-years of smoking, median (IQR)

13 (0–53)

22 (0–44)

20 (2–40)

0.925

Body mass indexa, mean ± SD

22.7 ± 3.8

24.1 ± 3.3

23.1 ± 3.2

0.162

FSSG score, median (IQR)

8 (0–10)

3 (1–6)

5 (2–12)

0.158

MRC chronic dyspnoea scale, median (IQR)a

2 (2–3)

1 (1–2)

1 (1–3)

0.036

Pulmonary function tests, % predicted, mean ± SDb

 FEV1

87.2 ± 20.6

89.2 ± 19.1

87.7 ± 21.5

0.903

 FVC

88.0 ± 24.3

89.8 ± 20.4

86.0 ± 20.4

0.664

 TLC

85.0 ± 24.0

83.2 ± 21.8

78.1 ± 22.8

0.476

 DLCO

50.9 ± 13.7

54.3 ± 15.5

50.7 ± 15.7

0.464

Composite Physiologic Index, mean ± SDb

40.9 ± 16.2

38.8 ± 13.6

42.3 ± 13.1

0.454

Medication, n (%)

 Glucocorticoid

1 (8)

27 (34)

15 (40)

0.132

 Antifibrotic agent

2 (17)

13 (17)

8 (21)

0.826

 Proton pump inhibitor

4 (33)

28 (35)

19 (50)

0.288

VAS score for cough, mm, median (IQR)

 Intensity

38 (26–45)*

15 (7–30)

54 (32–64)*

< 0.001

 Frequency

67 (64–82)*†

14 (5–30)

21 (10–32)

< 0.001

Leicester Cough Questionnaire score, median (IQR)

 Physical

4.8 (3.4–5.7)*†

6.3 (5.9–6.6)

5.9 (5.3–6.4)*

< 0.001

 Psychological

4.9 (3.9–6.4)*

6.7 (6.0–7.0)

6.3 (5.7–6.9)

0.002

 Social

4.9 (3.9–6.1)*†

7.0 (6.0–7.0)

6.6 (5.5–7.0)

0.001

 Total

13.9 (11.1–18.2)*†

19.6 (18.0–20.6)

18.7 (17.1–20.1)

< 0.001

  1. To explore the features associated with a differences between the VAS scores for cough intensity and cough frequency, we stratified patients into three categories using the following formula: (cough intensity) − (cough frequency), defining a cough frequency-dominant group, ≤10 mm; an equal cough severity group, −9 mm to 9 mm; and a cough intensity-dominant group, ≥10 mm. p-values are shown for across-group comparisons using one-way analysis of variance, the Kruskal-Wallis test, chi-square test, or Fisher’s exact test as appropriate. Using a nominal 5% level of statistical significance, multiple comparisons were made using a Bonferroni-corrected significance level of 1.6% (p < 0.016). CHP, chronic hypersensitivity pneumonia; CTD-ILD, connective tissue disease-associated interstitial lung disease; DLco, diffusing capacity of the lung for carbon monoxide; FEV1, forced expiratory volume in 1 s; FSSG, frequency scale for symptoms of gastro-oesophageal reflux disease; FVC, forced vital capacity; IIPs, idiopathic interstitial pneumonias; IQR, interquartile range; MRC, Medical Research Council; SD, standard deviation; TLC, total lung capacity; VAS, visual analogue scale. aCough frequency-dominant group (n = 12), equal cough severity group (n = 78), cough intensity-dominant group (n = 38); bCough frequency-dominant group (n = 11), equal cough severity group (n = 77), cough intensity-dominant group (n = 35). *p < 0.016 vs equal cough severity group; †p < 0.016 vs cough intensity-dominant group
Back to article page

BMC Pulmonary Medicine

ISSN: 1471-2466

Contact us