Influence of hospital volume and outcomes of adult structural heart procedures

Table 3 Hospital volume and primary outcome, length of hospital stay > 2 d, and predictor of highest quartile of cost of care (> $17160) following atrial septal defect/patent foramen ovale closure: Multivariate adjusted model

	Primary outcome		Length of stay		Cost of care
	OR (95%CI)	P value	OR (95%CI)	P value	OR (95%CI)	P value
Hospital volume (n of procedure per yr)
1st tertile (< 14)	Referent		Referent		Referent
2nd tertile (14-37)	0.73 (0.57-0.93)	0.013	0.50 (0.36-0.69)	< 0.001	0.72 (0.49-1.07)	0.104
3rd tertile (> 37)	0.67 (0.48-0.94)	0.019	0.37 (0.24-0.57)	< 0.001	2.55 (1.54-4.20)	< 0.001

Three levels hierarchical mixed effects models were generated (patient level factors nested within hospital level factors) with the unique hospital identification number incorporated as random effects. Primary outcome (n = 6328) was adjusted for age, sex, Deyo’s modification of Charlson Comorbidity Index, Median Household income, primary payer, hospital teaching status, emergent/urgent admission, weekend admission, Intracardiac Echocardiography use during procedure and hospital volume. In length of stay > 2 d (n = 6302) and predictors of highest quartile of cost (> 17160 $) (n = 5389), we included all variables in primary outcome. Hospital volume were calculated based on the unique hospital identification number on year to year basis. OR: Odds ratio.