Association between Helicobacter pylori seropositivity and mild to moderate COPD: clinical implications in an Asian country with a high prevalence of H. pylori

Figures & data

Table 1 Baseline clinical characteristics of COPD patients and control group

Characteristics	COPD (n=201)	Control (n=402)	P-value
Age, years	60.68±8.24	60.68±8.23
Male (%)	175 (87.1)	350 (87.1)
Body mass index, kg/m^2	24.07±3.02	24.16±2.73	0.685*
Height	1.68±0.069	1.67±0.069	0.095*
Smoking status (%)			<0.001
Current smoker	73 (36.3)	86 (21.4)
Exsmoker	95 (47.3)	166 (41.3)
Nonsmoker	31 (15.4)	144 (35.8)
Median pack-years (IQR)	25 (15.0–40.0)	20.0 (12.5–35.0)	0.312
Spirometry
FEV1	2.58±0.59	3.04±0.53	<0.001*
FEV1(%)	88.6±14.94	106.0±13.02	<0.001*
FVC	3.91±0.812	3.83±0.66	0.241*
FVC (%)	96.8±13.52	96.6±11.27	0.833*
FEV1/FVC	65.91±6.18	79.45±5.13	<0.001*
Hypertension (%)	59 (29.4)	121 (30.1)	0.850**
Diabetes mellitus (%)	27 (13.5)	67 (16.7)	0.313**
Chronic kidney disease (%)	1 (0.5)	10 (2.5)	0.111**
Iron deficiency anemia (%)	0 (0)	2 (0.5)	0.555**
Cardiovascular disease (%)			0.711**
Coronary artery disease	3 (1.5)	8 (2.0)
Cerebrovascular disease	2 (1.0)	2 (0.5)

Notes: Continuous data are shown as mean ± SD,

* P-value from t-test,

** P-value from Fisher’s exact test.

Abbreviations: FEV₁, forced expiratory volume in 1 second; FVC, forced vital capacity; IQR, interquartile range; SD, standard deviation.

Table 2 The prevalence of positive Helicobacter pylori serology by COPD stage

	COPD (n=201)	Control (n=402)	P-value
H. pylori IgG seropositivity n(%)	92 (45.8)	210 (52.2)	0.134
H. pylori IgG level, units/mL Median (IQR)	114.8 (33.6–191.0)	109.6 (34.3, 166.4)	0.549

Notes:

* P-value from chi-squared test,

** P-value from Mann-Whitney test.

Abbreviations: IgG, immunoglobulin G; IQR, interquartile range.

Figure 1 Helicobacter pylori serum IgG levels in COPD patients and control subjects.

Note: Displayed as median ± IQR.
Abbreviations: IgG, immuno globulin G; IQR, interquartile range.

Table 3 The association of seropositivity of Helicobacter pylori and CLO tests

	H. pylori seropositive (119)	H. pylori seronegative (117)
CLO positive patients (89)	71 (79.8%)	18 (20.2%)
CLO negative patients (147)	48 (32.7%)	99 (67.3%)

Notes: Kappa index: 0.442, P<0.001.

Figure 2 Correlation between Helicobacter pylo IgG titer and FEV₁.

Notes: The distribution of H. pylori IgG titer according to the airflow limitation. Linear regression of the H. pylori IgG versus FEV₁ (%). No significant correlation was found between two variables (n=187, r=−0.071, P=0.333).
Abbreviations: FEV₁, forced expiratory volume in 1 second; IgG, immunoglobulin G.

Table 4 Univariate and multivariate analysis of Helicobacter pylori seropositivity

Variables	Seropositivity				CLO positivity
	Unadjusted OR (95% CI)	P-value	Adjusted OR (95% CI)	P-value	Unadjusted OR (95% CI)	P-value	Adjusted OR (95% CI)	P-value
Smoking	0.857 (0.602–1.220)	0.391	0.909 (0.630–1.313)	0.612	1.304 (0.668–2.544)	0.464	1.296 (0.647–2.596)	0.464
CVD	1.510 (0.531–4.297)	0.440	1.340 (0.467–3.845)	0.586	0.991 (0.231–4.250)	0.990	0.900 (0.208–3.899)	0.888
Gastritis/peptic ulcer	1.343 (0.761–2.371)	0.309	1.132 (0.629–2.037)	0.679	4.4 (0.532–36.372)	0.169	3.961 (0.468–33.519)	0.207
GERD	0.482 (0.322–0.721)	<0.001	0.485 (0.321–0.733)	0.001	0.494 (0.241–1.013)	0.054	0.527 (0.254–1.091)	0.084
COPD	0.772 (0.550–1.084)	0.135	0.778 (0.546–1.108)	0.164	1.023 (0.597–1.755)	0.933	1.014 (0.577–1.781)	0.963

Note: P-value from multiple logistic regression analysis, adjusting for sex, age, smoking status, gastric diseases known to be related to H. pylori infection, and the severity of airflow limitation as defined by FEV₁.

Abbreviations: CI, confidence interval; GERD, gastroesophageal reflux disease; OR, odds ratio; CVD, cardiovascular disease.

Table 5 Impact of Helicobacter pylori test on the lung function decline

Total (195)	H. pylori seropositive (93)	H. pylori seronegative (102)	P-value
FEV1 (SE)	7.8 mL/year (6.8)	6.8 mL/year (6.6)	0.92
FVC (SE)	28.9 mL/year (8.7)	27.4 mL/year (8.5)	0.90

Note: Adjusted by age, sex, BMI, initial FEV₁ or FVC, smoking status.

Abbreviations: BMI, body mass index; FEV₁, forced expiratory volume in 1 second; FVC, forced vital capacity; SE, standard error.

Figure 3 Impact of Helicobacter pylori seropositivity on lung function decline.

Notes: (A) FEV₁ decline and (B) FVC decline.
Abbreviations: FEV₁, forced expiratory volume in 1 second; FVC, forced vital capacity.