Sickle Cell Disease May Not Worsen COVID-19 Prognosis

By Will Boggs MD

July 07, 2020

NEW YORK (Reuters Health) - Sickle cell disease does not appear to worsen the prognosis of COVID-19, at least not in younger patients, although vaso-occlusive crisis is common with the infection, researchers in France report.

Patients with sickle cell disease (SCD) are thought to be at increased risk of COVID-19 complications, but there are currently no data on the outcomes of these patients.

Dr. Jean-Benoit Arlet of the French Sickle Cell Referral Center, George Pompidou European Hospital, in Paris, and colleagues evaluated outcomes of 83 inpatients with sickle cell disease infected by SARS-CoV-2 from 24 French centers.

The patients ranged in age from 19 to 68 years (median, 33.5 years), the authors report in The Lancet Haematology. Most had hemoglobin SS/Sbeta(o)-thalassemia (SS/Sb(o), 86%), with fewer patients having hemoglobin SC (10%) or Sbeta(+)-thalassemia (5%).

Vaso-occlusive crisis in association with COVID-19 developed in 54% (44/81) of patients, and acute chest syndrome was associated with COVID-19 in 28% (23/82).

One in five patients (17/83) required admission to the intensive-care unit (ICU), and nine of these required mechanical ventilation. ICU admission was more common among patients with SC genotype (5/8, 63%) than among those with SS/Sb(o) genotype (12/71, 17%).

The prevalence of ICU admission was significantly lower among patients younger than 45 years (9/68, 13%) than among older ones (8/15, 53%).

Compared with all other inpatients who tested positive for COVID-19 within the same age range, those with sickle cell disease had 56% lower odds of ICU admission for young adults (15-44 years, P=0.039) but 76% higher odds of ICU admission for older adults (45-65 years, P=0.28).

Most patients admitted to the ICU (15/17, 88%) required transfusion with a median four units of packed red blood cells per patient.

Two patients died in the ICU with COVID-19 pneumopathy, both men with hemoglobin SC.

"These results suggest that COVID-19, even if potentially severe, does not seem to carry an increased risk of morbidity or mortality in patients with sickle cell disease, as most patients worldwide have the SS/Sb(o) genotype and are younger than 45 years," the authors conclude.

Dr. Victor R. Gordeuk of the University of Illinois at Chicago, who recently reported four cases of COVID-19 in patients with sickle cell disease (SCD), told Reuters Health by email, "Overall, it was encouraging that the severity of COVID-19 was not markedly worse in patients with SCD, especially those under age 45. The numbers are small and therefore firm conclusions cannot be drawn. However, the data raises the concern that patients over age 45 and especially those with hemoglobin SC may be especially vulnerable to COVID-19."

"We can provide some reassurance about COVID-19 to our younger patients with SCD," he said. "But we need to especially emphasize social distancing and prevention in older patients."

"Enrolling our patients in registries of COVID-19 may provide surprising information: for example, does something about hemoglobin SS disease provide relative protection from severe COVID-19?" Dr. Gordeuk added. "An interesting parallel may be HIV disease: some data suggests that SCD patients are relatively protected from severe complications."

Dr. Arlet did not respond to a request for comments.

SOURCE: Lancet Haematology, online June 18, 2020.