“To the best of our knowledge, this is the first United States nationwide investigation into lifetime survival for individuals with sickle cell disease covered by Medicare and Medicaid and disparities in survival by public insurance type, using comprehensive claims data collected from all 50 states,” the authors report in the study, published in Blood Advances.
“Our study underscores the persistent life expectancy shortfall for patients with sickle cell disease, the burden of premature mortality during adulthood, and survival disparities by insurance status,” they write.
SCD, which disproportionately affects people of African descent, significantly increases the risk of various acute and chronic life-threatening complications, including acute pain crisis, stroke, acute chest syndrome, chronic pain, symptomatic anemia, infections, and organ damage.
In recent years, advances ranging from newborn screening to prophylactic antibiotics have significantly improved the survival rates of children with SCD in the United States. However, premature mortality in adulthood has remained well above that of the general public.
A recent study of a U.S. birth cohort predicted life expectancy with SCD to be approximately 2 decades shorter than in those without the disease. However, those projections were based on a simulation model, and other life expectancy estimates have had sample sizes with state or regional limitations.
With no population-level individual data–based periodic life tables existing for individuals with SCD, the authors turned to nationwide data on Medicare and Medicaid beneficiaries to get a better idea of survival predictions.
For the study, they identified 94,616 individuals diagnosed with SCD who had not undergone transplant and were receiving common care, based on nationwide Medicare and Medicaid claim data from 2008 to 2016 on beneficiaries in all 50 states.
Of the patients, 74% were Black and 53% resided in the South at the index date. The patients had a mean entry age overall of 26.6 years across insurance types.
The results showed projected life expectancy at birth with SCD to be 52.6 years, with the life expectancy at birth for females significantly longer, compared with that of males (55.0 versus 49.3 years). For the general population, U.S. life expectancy estimates have been reported to be about 76 years.
Specifically, life expectancy in the cohort into adulthood was 35.4 years at 18 years of age; 24.1 years at 35 years of age; 19.6 years at 45 years old; 13.2 years at 65 years of age; and 5.4 years at 85 years old.
Likewise, survival probability rates were high during childhood, with survival probability at 18 years being 0.98, declining to 0.804 at age 30; 0.628 at age 45; 0.267 at age 65 and 0.70 at age 85.
Black individuals had a significantly shorter life expectancy at birth than non-Black individuals (52.2 vs. 55.1 years), with the survival expectancy for Black individuals significantly shorter than the 75-year life expectancy estimated by the 2016 U.S. Centers for Disease Control and Prevention life table for the Black population in general.
Of the patients, only 5% had Medicare old age and survivor’s insurance, and 4% had Medicare disability insurance benefits or end-stage renal disease (ESRD), while 48% had Medicaid, and 43% were dually eligible for Medicare and Medicaid. The racial and regional distributions were similar across insurance types.
Adults covered by Medicare had a life expectancy of 39.8 years at 18 years of age, an improvement over life expectancy for those with Medicare for disabilities or ESRD and those dually insured by Medicare and Medicaid.
And the shorter life expectancy with Medicare and Medicaid was also observed among beneficiaries aged 65 or older, compared with those enrolled in Medicare old age and survivor’s insurance.
“Evidently, the life expectancy gap persists among patients with sickle cell disease, even though they are protected by public insurance,” the authors report.
The shorter life expectancy among those with dual eligibility for Medicare and Medicaid is consistent with that of the general population, the authors add.
“It is well-recognized that the dual-eligible individuals are a vulnerable population with some of the most complex and expensive health care needs,” they write. “They are more likely to have fewer socioeconomic resources, more chronic conditions, and poorer survival outcomes than single eligible.”
First author Boshen Jiao, PhD, MPH, of the Harvard T.H. Chan School of Public Health, in Boston, noted that socioeconomic factors, on a broader level, have an important impact on SCD.
“Even the first and most established FDA-approved medication for sickle cell disease, hydroxyurea, suffers from underutilization,” he told MDedge. “This issue can be associated with disparities along racial lines, particularly concerning access to treatments.”
Such factors can also play a role in the lack of a well-coordinated transition program needed to prevent gaps in care between youth and adulthood, as well as a lack of access to specialized care needed to potentially initiate new therapies.
Ultimately, the decline in survival seen from childhood to adulthood in SCD “emphasizes the pivotal role of health care during the critical transition phase from childhood to adulthood for individuals with sickle cell disease,” Dr. Jiao said. “Moreover, the prospect of a curative therapy that can intervene in the early stages of life, prior to adulthood, stands as a desirable goal.”
The authors urge that “future studies should uncover factors influencing survival outcomes and explore policy options to address the unmet needs of the disabled or dually eligible population with SCD.” They had no disclosures to report.
A version of this article first appeared on Medscape.com.