Scabies increased the risk and severity of COPD: a nationwide population-based study

Figures & data

Figure 1 Flowchart of recruitment of subjects from the 1-million random sample of the NHIRD from 2000 to 2006 in Taiwan.

Abbreviations: COPD, chronic obstructive pulmonary disease; NHIRD, National Health Insurance Research Database.

Table 1 Demographic characteristics associated with patients with scabies and control group

Characteristics	Patients with scabies, n (%)	Control subjects, n (%)	P-value
Number of cases	3,568 (20.0)	14,255 (80.0)
Gender
Female	1,782 (49.9)	7,122 (50)	0.99
Male	1,786 (50.1)	7,133 (50)
Age, years
40–49	1,159 (32.5)	4,634 (32.5)	1
50–59	851 (23.9)	3,404 (23.9)
60–69	562 (15.8)	2,239 (15.7)
≥70	996 (27.9)	3,978 (27.9)
Insured region
Northern Taiwan	1,427 (40)	6,968 (48.9)	<0.001*
Middle Taiwan	687 (19.3)	2,500 (17.5)
Southern Taiwan	1,268 (35.5)	4,360 (30.6)
Other (Eastern Taiwan and outlying islands)	186 (5.2)	427 (3)
Urbanization
1 (highest)	805 (22.6)	4,133 (29)	<0.001*
2	1,023 (28.7)	4,082 (28.6)
3	593 (16.6)	2,414 (16.9)
4	638 (17.9)	2,126 (14.9)
5	106 (3)	341 (2.4)
6	217 (6.1)	632 (4.4)
7 (lowest)	186 (5.2)	527 (3.7)
Insured amount, NTDa
<20,000	2,840 (79.6)	10,915 (76.6)	<0.001*
20,000–39,999	428 (12)	1,752 (12.3)
40,000–59,999	208 (5.8)	1,045 (7.3)
≥60,000	92 (2.6)	543 (3.8)
Comorbidity
Diabetes mellitus	1,182 (33.1)	2,600 (18.2)	<0.001*
Hypertension	1,935 (54.2)	5,160 (36.2)	<0.001*
Congestive heart failure	415 (11.6)	750 (5.3)	<0.001*
Coronary heart disease	1,019 (28.6)	2,425 (17)	<0.001*
Chronic kidney disease	351 (9.8)	576 (4)	<0.001*
Osteroporosis	427 (12)	1,218 (8.5)	<0.001*

Notes:

a 1 US dollar =33 NTD.

* P<0.05.

Abbreviation: NTD, New Taiwan dollars.

Table 2 COPD incidence between patients with scabies and control group

	Patients with scabies (n=3,568)	Patients without scabies (n=14,255)
With COPD, n (%)	904 (25.3)	1,861 (13.1)
Without COPD, n (%)	2,664 (74.7)	12,394 (86.9)
Crude HR (95% CI)	2.15 (1.98–2.32)**

Note:

** P<0.001 for comparison between the two groups of patients.

Abbreviations: HR, hazard ratio; COPD, chronic obstructive pulmonary disease.

Table 3 Independent risk factors of COPD identified by Cox regression analysis in the 5-year follow-up period

	Crude HR (95% CI)	Adjusted HR (95% CI)
Scabies	2.15 (1.98–2.32)**	1.72 (1.59–1.87)**
Gender
Female	1	1
Male	1.19 (1.10–1.28)**	1.27 (1.18–1.38)**
Age, years
40–49	1	1
50–59	1.66 (1.47–1.87)**	1.35 (1.19–1.53)**
60–69	2.44 (2.15–2.76)**	1.59 (1.39–1.81)**
≥70	3.19 (2.87–3.55)**	2.03 (1.80–2.28)**
Insured region
Northern Taiwan	1	1
Middle Taiwan	1.20 (1.08–1.33)**	1.09 (0.98–1.22)
Southern Taiwan	1.18 (1.09–1.29)**	1.05 (0.95–1.15)
Other (Eastern Taiwan and outlying islands)	1.23 (1.01–1.50)*	0.94 (0.77–1.16)
Urbanization
1 (highest)	1	1
2	1.05 (0.95–1.17)	0.97 (0.87–1.07)
3	1.07 (0.95–1.21)	0.99 (0.87–1.11)
4	1.28 (1.14–1.43)**	1.03 (0.91–1.16)
5	1.30 (1.03–1.64)*	0.86 (0.68–1.1)
6	1.41 (1.19–1.67)**	1.01 (0.84–1.21)
7 (lowest)	1.5 (1.25–1.80)**	1.09 (0.90–1.31)
Insured amount, NTDa
<20,000	1	1
20,000–39,999	0.67 (0.59–0.76)**	0.98 (0.86–1.13)
40,000–59,999	0.62 (0.52–0.74)**	0.95 (0.79–1.14)
≥60,000	0.54 (0.41–0.69)**	0.76 (0.59–0.99)*
Comorbidity
Diabetes mellitus	1.94 (1.79–2.10)**	1.02 (0.94–1.12)
Hypertension	3.04 (2.81–3.28)**	1.77 (1.62–1.94)**
Congestive heart failure	4.03 (3.66–4.43)**	1.74 (1.56–1.94)**
Coronary heart disease	3.34 (3.10–3.60)**	1.81 (1.66–1.98)**
Chronic kidney disease	2.61 (2.32–2.93)**	1.15 (1.01–1.30)*
Osteoporosis	1.92 (1.74–2.13)**	1.26 (1.13–1.40)**

Notes:

a 1 US dollar =33 NTD.

* P<0.05,

** P<0.001.

Abbreviations: HR, hazard ratio; NTD, New Taiwan dollars; COPD, chronic obstructive pulmonary disease.

Table 4 The association between scabies and major COPD complications analyzed by Cox regression

COPD complication	With scabies (n=3,568), n (%)	Without scabies (n=14,255), n (%)	Crude HR (95% CI)	Adjusted HR (95% CI)
COPD
No	2,664 (74.7)	12,394 (86.9)	1	1
Yes	904 (25.3)	1,861 (13.1)	2.15 (1.98–2.32)**	1.72 (1.59–1.87)**
COPD without complication
No	3,324 (93.2)	13,583 (95.3)	1	1
Yes	244 (6.8)	672 (4.7)	1.61 (1.39–1.86)**	1.33 (1.15–1.55)**
COPD with acute exacerbation
No	2,981 (83.5)	13,148 (92.2)	1	1
Yes	587 (16.5)	1,107 (7.8)	2.34 (2.12–2.59)**	1.85 (1.67–2.06)**
COPD with pneumonia
No	3,289 (92.2)	13,964 (98)	1	1
Yes	279 (7.8)	291 (2)	4.22 (3.58–4.98)**	3.29 (2.77–3.92)**
COPD with acute respiratory failure
No	3,427 (96)	14,140 (99.2)	1	1
Yes	141 (4)	115 (0.8)	5.38 (4.21–6.88)**	4.00 (3.08–5.20)**
COPD with cardiopulmonary arrest
No	3,538 (99.2)	14,230 (99.8)	1	1
Yes	30 (0.8)	25 (0.2)	5.26 (3.09–8.95)**	3.95 (2.25–6.95)**

Note:

** P<0.001.

Abbreviations: COPD, chronic obstructive pulmonary disease; HR, hazard ratio; CI, confidence interval.