The answer, according to a year 2000 study published in The American Journal of Medicine (lead author: Kossovksy), is both.
PURPOSE: To determine if early unplanned readmissions of patients hospitalized for heart failure are associated with suboptimal in-hospital care or with the clinical and demographic characteristics of the patient.
SUBJECT AND METHODS: We performed a case-control study among patients discharged with a principal diagnosis of heart failure. Cases included all patients unexpectedly readmitted within 31 days of discharge; controls were randomly selected from among those not readmitted. Quality of care was measured using explicit criteria reflecting the admission work-up, evaluation and treatment, and readiness for discharge.
RESULTS: Ninety-one cases and 351 controls were included. There was no significant association between early unplanned readmissions and the scores for quality of the admission work-up or evaluation and treatment during the stay. There was a significant association between readiness for discharge and subsequent early readmission: for each 10% decrease in the proportion of fulfilled criteria, the odds of readmission increased by 14% (95% confidence interval [CI] 1. 01 to 1.28, P = 0.04) for all-cause readmissions and by 19% (95% CI: 1.04 to 1.36, P = 0.01) for heart-failure-related readmissions. In a multiple logistic regression model, previous diagnosis of heart failure (odds ratio [OR] = 2.9, 95% CI: 1.7 to 4.8, P <0.001), age (OR = 3.3, 95% CI: 1.3 to 8.5, P = 0.01 for patients aged 65 to 79 years and OR = 4.1, 95% CI: 1.6 to 11, P = 0.004 for patients aged 80 years and older), and history of cardiac revascularization (OR = 2.1, 95% CI: 1.2 to 3.9, P = 0.01) showed a stronger association with early unplanned all-cause readmissions than the readiness-for-discharge score (OR = 1.16, 95% CI: 1.02 to 1.31, P = 0.02). Similar findings were seen for heart failure-related readmissions.
CONCLUSIONS: Among patients with heart failure, early unplanned readmissions were not associated with suboptimal admission work-up or evaluation and treatment but were weakly associated with readiness for discharge. However, they were strongly associated with the patients’ clinical and demographic characteristics.
The study used data from 1993-1998 who were seen in the main teaching hospital of the University Hospitals of Geneva, Switzerland. Another Swiss heart failure readmissions study by Luthi, et al. also found that process indicators were not related to readmissions. Note the contrast with the link between process safety indicators and readmissions found by Rosen, et al. There are differences between quality indictors and safety indictors (PDF). Moreover, it may matter which indicators one selects for analysis.
PS: I am aware of the new JAMA theme issue on readmissions. I am still reading the papers. I’ll post some things about them later this week or next.