PE incidence high in sickle cell patients
MedWire News: The incidence of pulmonary embolism (PE) is 50 to 100 times higher in people with sickle cell disease (SCD) than it is in the general population, show results of a study conducted in Pennsylvania, USA.
However, the prevalence of PE among people admitted to hospital is similar between those with and without SCD, report Margaret Ragni (University of Pittsburgh Medical Center, Pennsylvania) and colleagues.
"PE is a leading cause of mortality in hospitalized patients, yet the prevalence of PE in SCD and its relation to disease severity or intrinsic hypercoagulability are not established," say the researchers.
To address this, they estimated inpatient PE incidence and prevalence among people with and without SCD using the Pennsylvania Health Care Cost Containment Council discharge data for 2001-2006. The team also compared the severity of illness and mortality between the groups.
As reported in the Journal of Thrombosis and Haemostasis, the incidence of PE was substantially higher in the Pennsylvania residents with SCD than in those without SCD. For example, in 2006, 21 (0.52%) of a total of 4000 residents with SCD developed PE, compared with 2397 (0.0058%) of 41,255,577 residents without SCD.
By contrast, the prevalence of PE among people admitted to hospital with SCD during the 6-year study period (n=20,847) was similar to the prevalence in people admitted without SCD (n=11,134,765), at 0.57% versus 0.60%. Furthermore, prevalence did not change after adjustment for race.
Patients with PE and SCD had similar illness severity to those with PE but no SCD (8.1 vs 7.7% in the two highest categories) and similar inpatient mortality (6.2 vs 4.2%), but they underwent significantly fewer PE scans than the patients with PE and no SCD (42.0 vs 57.2%).
Among patients admitted to hospital with SCD for any reason, those developing PE were significantly older (37 vs 28 years), with longer length of hospital stay (9.2 vs 5.0 days), greater severity of illness (8.1 vs 3.3% in the two highest categories), and higher inpatient mortality (6.2 vs 1.4%), compared those who did not develop PE.
Ragni and co-authors say that the study "establishes the higher incidence of PE in individuals with SCD than in non-SCD individuals on a year-by-year basis."
They add: "Given the 6% mortality rate we found among SCD with PE, which is at least 4-fold greater than that among SCD without PE, and the evolving refinement of chest CT technology with potential for earlier PE detection, consideration should be given to a higher index of suspicion and a lower threshold for performing chest CT pulmonary angiography in SCD patients, particularly in those with pulmonary symptoms."
The team concludes by calling for prospective clinical studies to confirm the utility of this approach and determine whether prophylactic anticoagulation in hospitalized SCD patients is warranted.
By Laura Cowen