Prevalence of patient safety indicators and hospital-acquired conditions in those treated for unruptured cerebral aneurysms: establishing standard performance measures using the Nationwide Inpatient Sample database

Abstract

Object: The Agency for Healthcare Research and Quality (AHRQ) patient safety indicators (PSIs) and the Centers for Medicare and Medicaid Services hospital-acquired conditions (HACs) are metrics used to gauge the quality of health care provided by health care institutions. The PSIs and HACs are publicly reported metrics and are directly linked to reimbursement for services. To better understand the prevalence of these adverse events in hospitalized patients treated for unruptured cerebral aneurysms, the authors determined the incidence rates of PSIs and HACs among patients with a diagnosis of unruptured aneurysm in the Nationwide Inpatient Sample (NIS) database.

Methods: The NIS, part of the AHRQ's Healthcare Cost and Utilization Project, was queried for all hospitalizations between 2002 and 2010 involving coiling or clipping of unruptured cerebral aneurysms. The incidence rate for each PSI and HAC was determined by searching the hospital records for ICD-9 codes. The SAS statistical software package was used to calculate incidences and perform multivariate analyses to determine the effects of patient variables on the probability of each indicator developing.

Results: There were 54,589 hospitalizations involving unruptured cerebral aneurysms in the NIS database for the years 2002-2010; 8314 patients (15.2%) underwent surgical clipping and 9916 (18.2%) were treated with endovascular coiling. One thousand four hundred ninety-two PSI and HAC events occurred among the 8314 patients treated with clipping; at least 1 PSI or HAC occurred in 14.6% of these patients. There were 1353 PSI and HAC events among the 9916 patients treated with coiling; at least 1 PSI or HAC occurred in 10.9% of these patients. Age, sex, and comorbidities had statistically significant associations with an adverse event. Compared with the patients having no adverse event, those having at least 1 PSI during their hospitalizations had significantly longer hospital stays (p < 0.0001), higher hospital costs (p < 0.0001), and higher mortality rates (p < 0.0001).

Conclusions: These results estimate baseline national rates of PSIs and HACs in patients with unruptured cerebral aneurysms. These data may be used to gauge individual institutional quality of care and patient safety metrics in comparison with national data.