Introduction: Annual admissions for moyamoya have steadily increased from 4.9 to 15.4/1,000,000 since 1997. Here we report changes in treatment and complications during this period as derived from a national database.
Hypothesis: We assessed the hypothesis that increasing volume of moyamoya admissions over time would correlate with decreased hospital complications and length of stay.
Methods: The Kids Inpatient Database (KID) was queried for all pediatric admissions with a diagnosis of moyamoya from 1997, 2000, 2003, 2006, 2009, and 2012. Patient safety indicators (PSIs) and hospital acquired conditions (HACs) were identified using ICD-9 codes for procedures or secondary diagnoses. Trends in utilization and outcomes were determined by multivariate regression analysis.
Results: 2,452 admissions for moyamoya were identified. After controlling for patient and hospital factors, total use of MRI and cerebral angiography was stable (9.9-14.2% and 14-22% of admissions, respectively), but CT use decreased from 7.1% to 2.8% (p<0.0001). A 38.5% reduction in total procedures performed during each admission was observed (2.6 vs 1.6; p<0.0001). The percentage of admissions undergoing ECIC bypass increased significantly from 10.3% in 1997 to 22.4% in 2006, and remained stable through 2012 (22.1%, p<0.0001). PSIs and HACs have stayed stable at 4.8-7.9% and 2.0-4.0% per year, respectively. Comparing complications between operative and non-operative admissions, ECIC bypass patients experienced more accidental lacerations (0.44 vs 0.05%; p<0.02) and anesthetic complications (0.22 vs 0.15%; p<0.04), while nonoperative admissions had more respiratory failures (2.25 vs 0.44%, p<0.004). For all patients, an 85% decrease in meningitis (1.2% to 0.2%; p<0.001), a 29.2% decrease in inpatient stroke (13.6 vs 9.6%; p<0.0001), and a 32.7% decrease in inpatient seizures (29.0 vs 19.5%; p<0.0001) were observed. Length of stay decreased by 21.2% since 1997 (7.0 vs 5.6 days; p<0.0001).
Conclusions: Over the 15-year study period, inpatient treatment of moyamoya has improved significantly, including decreased utilization of ionizing radiation, stable rates of PSIs and HACs, decreased prevalence of inpatient strokes, meningitis, seizures and shorter length of stay.