Table 2.

Comparison of incidence and hazard ratio of chronic fatigue syndrome stratified by sex, age and comorbidity between patients with and without peptic ulcer disease.

Variable	Peptic ulcer disease						Crude HR (95% CI)	Adjusted HR† (95% CI)
	No			Yes
	Event	PY	Rate#	Event	PY	Rate#
All	313	521,915	0.60	645	532,843	1.21	2.01(1.75, 2.30)***	1.83(1.59, 2.11)***
Sex
Female	158	274,642	0.58	352	282,402	1.25	2.15(1.79, 2.60)***	2.06(1.69, 2.52)***
Male	155	247,273	0.63	293	250,441	1.17	1.86(1.53, 2.26)***	1.61(1.31, 1.97)***
Stratify age
≤ 49	45	111,983	0.40	107	119,112	0.90	2.22(1.56, 3.14)***	2.01(1.39, 2.89)***
50–65	49	175,368	0.52	204	178,893	1.14	2.19(1.71, 2.80)***	2.04(1.57, 2.65)***
65 +	177	234,563	0.75	334	234,839	1.42	1.87(1.56, 2.25)***	1.68(1.38, 2.03)***
Comorbidity‡
No	152	311,769	0.49	196	183,995	1.07	2.18(1.76, 2.69)***	2.23(1.80, 2.75)***
Yes	161	210,146	0.77	449	348,848	1.29	1.66(1.38, 1.98)***	1.71(1.43, 2.05)***

Rate#, incidence rate, per 1,000 person-years; Crude HR, crude hazard ratio.

Adjusted HR†: multivariable analysis including age, sex, and comorbidities of diabetes, obesity, renal disease, rhematoid arthritis, HIV, and malignancy, untreated hypothyroidism, sleep apnea, narcolepsy, HBV, HCV, depression, anxiety, bipolar affective disorders, schizophrenia, delusional disorders, dementia, anorexia or bulimia nervosa, and alcohol or other substance abuse.

Comorbidity‡: Patients with any one of the comorbidities diabetes, obesity, renal disease, rhematoid arthritis, HIV, malignancy, untreated hypothyroidism, sleep apnea, narcolepsy, HBV, HCV, depression, anxiety, bipolar affective disorders, schizophrenia, delusional disorders, dementia, anorexia or bulimia nervosa, and alcohol or other substance abuse were classified as the comorbidity group.

*p < 0.05, **p < 0.01, ***p < 0.001.