Predictors of In-Hospital Mortality and Home Discharge in Patients with Aneurysmal Subarachnoid Hemorrhage: A 4-Year Retrospective Analysis.

BACKGROUND: Factors associated with discharge disposition and mortality following aneurysmal subarachnoid hemorrhage (aSAH) are not well-characterized. We used a national all-payer database to identify factors associated with home discharge and in-hospital mortality. METHODS: The National Inpatient Sample was queried for patients with aSAH within a 4-year range. Weighted multivariable logistic regression models were constructed and adjusted for age, sex, race, household income, insurance status, comorbidity burden, National Inpatient Sample SAH Severity Score, disease severity, treatment modality, in-hospital complications, and hospital characteristics (size, teaching status, and region). RESULTS: Our sample included 37,965 patients: 33,605 were discharged alive and 14,350 were discharged home. Black patients had lower odds of in-hospital mortality compared with White patients (adjusted odds ratio [aOR] = 0.67, 95% confidence interval [CI] 0.52-0.86, p = 0.002). Compared with patients with private insurance, those with Medicare were less likely to have a home discharge (aOR = 0.58, 95% CI 0.46-0.74, p < 0.001), whereas those with self-pay (aOR = 2.97, 95% CI 2.29-3.86, p < 0.001) and no charge (aOR = 3.21, 95% CI 1.57-6.55, p = 0.001) were more likely to have a home discharge. Household income percentile was not associated with discharge disposition or in-hospital mortality. Paradoxically, increased number of Elixhauser comorbidities was associated with significantly lower odds of in-hospital mortality. CONCLUSIONS: We demonstrate independent associations with hospital characteristics, patient characteristics, and treatment characteristics as related to discharge disposition and in-hospital mortality following aSAH, adjusted for disease severity.

Use of magnetically purified Plasmodium falciparum parasites improves the accuracy of erythrocyte invasion assays.

Merozoite invasion of erythrocytes is a crucial step for the asexual cycle of Plasmodium falciparum. Multiple invasion pathways, which involve different ligand-receptor interactions, have been identified in P. falciparum by examining the entry of purified parasite into erythrocytes with different surface receptors, either mutant or under different enzyme treatments. The most critical step for a successful invasion assay is the isolation of erythrocytes infected with viable schizonts. Here, we applied a magnetic column to purify the schizonts for the erythrocyte invasion assay. Comparing to Percoll-sorbitol purification method, this modified approach showed great improvement on reproducibility and reliability of invasion assay, particularly for short-term, culture-adapted parasite isolates. The magnetic purification method is an excellent alternative for parasite isolates that do not tolerate or with unknown sensitivity to Percoll-sorbitol exposure.