Characterizing Mortality Among Individuals with Sickle Cell Disease in Michigan, 2010 – 2020

Abstract

Background
Sickle cell disease (SCD) is a rare, chronic condition associated with significant morbidity and early mortality. However, accurately estimating mortality rates among those living with SCD can be challenging in part due to the lack of population-level data regarding prevalence and deaths. Previous estimates have relied on cause of death from death certificates, single-institutions, or payer-dependent estimates and therefore, likely provide an inaccurate estimate of mortality.
Objective
To identify deaths from 2010 through 2020 and estimate the 5-year mortality rate among those with SCD in Michigan using population-level data.
Methods
The Michigan Sickle Cell Data Collection Program is a CDC-funded, population-based surveillance system that longitudinally collects and combines multiple data sources to characterize persons living with SCD and their health outcomes, including morbidity and mortality. Date of death was collected from vital records (2010-2020), Medicaid (2010-2020), and SCD clinics (2016-2019). Date of birth was subtracted from date of death to calculate age at death (years). We assessed mean and median age at death overall, by sex, and by age group (0-24, 25-44, 45-64, 65+ years). The 5-year mortality rate (2016 - 2020) was calculated overall and by age group. The numerator comprised number of deaths during this period, and the denominator comprised anyone with SCD living in Michigan anytime from 2016 through 2020 multiplied by the number of years included. Statewide mortality rates for the general population were obtained from CDC National Center for Health Statistics 2016 mortality data.
Results
Overall, we identified 557 deaths among individuals with SCD in Michigan (2010-2020). The mean age at death was 46 years (SD 18.1), ranging from 0 to 92 years; median age at death was 46 years, with females somewhat higher (48 years) than males (45 years). The greatest number of SCD deaths (40%) occurred among those 45-64 years, followed by the 25-44 age group (34%), 65+ age group (14%) and 0-24 age group (12%). The overall 5-year mortality rate was 1,565 deaths per 100,000 person-years; mortality rates for the age groups 0-24, 25-44, 45-64, 65+ were 305, 1,388, 3,783, and 8,135, 1,249, 3,168, and 7,255 deaths per 100,000 people, respectively.
Conclusion
Across all age groups, the mortality rate among individuals with SCD was substantially higher than the general Michigan population, particularly among young adults who had a mortality rate almost seven times higher than the general population. These findings highlight the need to focus additional efforts to reduce mortality in young adults with SCD during the transition from pediatric to adult care.

Categories: Conference Abstracts/Posters