Table 3.

Comorbidity and aHR of depression

Comorbidity	n	Event	Person-years	Incidence ratea	HR (95% CI)
					Model 1	Model 2	Model 3
Diabetes mellitus
No
Control	2 02,135	18,470	956,972.07	19.3005	1 (Ref.)	1 (Ref.)	1 (Ref.)
Cholecystectomy	94,444	11,369	436,207.81	26.0633	1.36 (1.328, 1.392)	1.376 (1.344, 1.408)	1.359 (1.327, 1.391)
Yes
Control	21,733	2,931	97,997.9	29.9088	1 (Ref.)	1 (Ref.)	1 (Ref.)
Cholecystectomy	17,490	2,653	77,628.79	34.1755	1.148 (1.089, 1.21)	1.165 (1.105, 1.228)	1.166 (1.106, 1.229)
Hypertension
No
Control	1 67,476	14,125	794,826.97	17.7712	1 (Ref.)	1 (Ref.)	1 (Ref.)
Cholecystectomy	74,465	8,323	345,264.02	24.1062	1.365 (1.329, 1.403)	1.394 (1.357, 1.433)	1.378 (1.341, 1.416)
Yes
Control	56,392	7,276	26 0,143	27.9692	1 (Ref.)	1 (Ref.)	1 (Ref.)
Cholecystectomy	37,469	5,699	168,572.59	33.8074	1.217 (1.176, 1.26)	1.253 (1.21, 1.297)	1.244 (1.201, 1.288)
Dyslipidemia
No
Control	1 90,415	17,046	905,510.6	18.8247	1 (Ref.)	1 (Ref.)	1 (Ref.)
Cholecystectomy	89,292	10,570	414,729.08	25.4865	1.363 (1.33, 1.396)	1.369 (1.336, 1.403)	1.349 (1.316, 1.382)
Yes
Control	33,453	4,355	149,459.37	29.1384	1 (Ref.)	1 (Ref.)	1 (Ref.)
Cholecystectomy	22,642	3,452	99,107.52	34.8309	1.202 (1.15, 1.257)	1.24 (1.186, 1.297)	1.239 (1.185, 1.296)

aHR, adjusted HR; CI, confidence interval; HR, hazard ratio.

Model 1: nonadjusted.

Model 2: adjusted for age.

Model 3: adjusted for age, sex, income, place of residence, diabetes mellitus, hypertension, and dyslipidemia.

^aIncidence rate: per 1,000 person-years