Effects of Comorbidities on Asthma Hospitalization and Mortality Rates: A Systematic Review

Table 2

Study characteristics.

Author (year)	Research type	Population			Study length (years)	C	MD	O	DM	OSA
		Total	Control (asthma-only)	Comorbid condition
Kendzerska et al. [8]	Retrospective cohort	—	—	—	10	M
Baarnes et al. [9]	Retrospective cohort	57,053	1,845	662	4	M
Yamauchi et al. [10]	Retrospective cohort	30,405	19,865	6,279	3	M and ER
Harada et al. [11]	Retrospective	650	474	176	12	M
Becerra et al. [12]	Inpatient sample study	179, 789	136,118	8,189	3					LOS
Vuillermin et al. [13]	Cross-sectional analysis	615	410	205	1		ER
Ahmedani et al. [14]	Prospective follow-up study	568	N/A	187	1		ER
Wiesenthal et al. [15]	Prospective follow-up study	460	227	233	3			ER
Hsiao et al. [16]	Retrospective cohort	17,725	766	3,545	13				ER

Description of results from each selected article regarding the significant differences in hospital/emergency room (ER) visits, mortality (M), and hospital length of stay (LOS) in patient due to the chronic disease comorbidity compared to the asthma-only control. C,  COPD/asthma comorbidity; MD,  mental disorder/asthma comorbidity; O,  obesity/asthma comorbidity; D ,  diabetes mellitus/asthma comorbidity; OSA ,  obstructive sleep apnea. This paper utilized a population health administrative data for all individuals living in Ontario, Canada (population of approximately 13 million in 2010) that are over the age of 35. No articles were found that discussed the clinical impacts of either hypertension-asthma, myocardial ischemia-asthma, or rhinitis/sinusitis-asthma comorbidity.