Table 3.

Subgroup analysis of crude and adjusted hazard ratios (95% confidence interval) of rheumatoid arthritis for asthma according to age and sex.

Characteristics	Asthma
	Crude†	P-value	Adjusted†,‡	P-value
Age <40 years old, men (n = 2,080)
Rheumatoid arthritis	1.64 (1.08–2.49)	0.021*	1.50 (0.98–2.30)	0.063
Control	1.00		1.00
Age <40 years old, women (n = 4,660)
Rheumatoid arthritis	1.40 (1.14–1.70)	0.001*	1.28 (1.05–1.57)	0.017*
Control	1.00		1.00
Age 40–59 years old, men (n = 3,370)
Rheumatoid arthritis	2.32 (1.80–2.99)	<0.001*	2.21 (1.71–2.85)	<0.001*
Control	1.00		1.00
Age 40–59 years old, women (n = 13,970)
Rheumatoid arthritis	1.17 (1.05–1.30)	0.003*	1.10 (0.99–1.22)	0.074
Control	1.00		1.00
Age ≥60 years old, men (n = 2,395)
Rheumatoid arthritis	1.55 (1.18–2.04)	0.002*	1.46 (1.11–1.93)	0.007*
Control	1.00		1.00
Age ≥60 years old, women (n = 7,000)

^*Cox-proportional hazard regression model, Significance at P < 0.05.

^†Stratified model for age, income, and region of residence, hypertension, diabetes mellitus, and dyslipidemia histories.

^‡Adjusted model for depression histories, and Charlson Comorbidity Index.