Cerebrovascular Accidents Among African American Adults with Sickle Cell Disease: A Nationwide Outcomes and Trend Analysis over Two Decades

Introduction: With nearly half of individuals with sickle cell disease (SCD) surviving into the sixth decade of life, there is a need to examine the incidence, mortality and outcomes of cerebrovascular accidents (CVA) in African American (AA) adults with SCD.

Methods: We conducted a retrospective analysis of yearly hospitalizations of AA adults who presented to acute care hospitals in the USA, between 2000 and 2014 using the Healthcare Cost and Utilization Project's Nationwide Inpatient Sample (NIS) database. Diagnoses were identified using the appropriate ICD9-CM codes. Inclusion criterion was a principal diagnosis of CVA. The exposure of interest was at least one ICD9 code for SCD comorbidity. Proportions and means were compared using appropriate bivariate statistics. Analyses of trends over time were computed using multivariable time series analysis.

Results: The annual proportion of individuals with SCD among all AA adults admitted for CVA (N = 1,294,288) rose from 0.16% in 2000 to 0.38% in 2014, p<0.01. Correspondingly, the rate of hospitalizations for CVA among AA adults admitted with co-morbid SCD (N= 1,005,135), more than doubled from 0.2% in 2000 to 0.47% in 2014, p<0.01. Patients over 50 years of age were the main group affected. Interestingly, the rate of hospitalizations for ischemic strokes increased in parallel from 0.14% in 2000 to 0.37% in 2014, whereas the rate of hospitalizations for hemorrhagic strokes plateaued after year 2002 and ranged between 0.1% and 0.12%.

In addition, the inpatient mortality of SCD patients with primary diagnosis of CVA varied from 7.6% to 17.6% between years 2000 and 2005, and then steadily decreased after 2005 to reach 4.7% in 2014. Co-morbid HTN rates increased among all admitted AA SCD adult patients (9.6% in 2000 to 22.1% in 2014, p<0.01) and more so among those admitted with a CVA (18% in 2000 to 63.5% in 2014, p<0.01). Furthermore, hospitalizations charges averaged $61,326 for AA SCD patients with CVA, compared with $27,029 for all AA SCD patients admitted from 2000 till 2014. Compared to all hospitalized AA adults with SCD, patients with CVA had on average longer hospital stays (7.7 days vs. 5.8 days) during the study period.

Conclusion: The rate of cerebrovascular accident hospitalizations among adult African Americans with sickle cell disease has doubled over the past two decades. Fortunately, the inpatient mortality has decreased.