Table 6. Incidence and adjusted hazard ratio of incident respiratory failure between non-SLE and SLE cohorts by propensity score matching.

	SLE
		No			Yes		Compared to non-SLE cohort
Variables	Event	PY	Rate	Event	PY	Rate	IRR (95% CI)	Hazard Ratio (95% CI)
Overall	271	204242	1.33	488	65457	7.46	5.62(5.27–5.99)***	7.84(5.82–10.6)***

SLE, systemic lupus erythematosus; PY: person-year; Rate: incidence rate (per 1,000 person-years); IRR, incidence rate ratio;

***p<0.001.