Severe painful vaso-occlusive crises and mortality in a contemporary adult sickle cell anemia cohort study.
BACKGROUND
Frequent painful vaso-occlusive crises (VOCs) were associated with mortality in the Cooperative Study of Sickle Cell Disease (CSSCD) over twenty years ago. Modern therapies for sickle cell anemia (SCA) like hydroxyurea are believed to have improved overall patient survival. The current study sought to determine the relevance of the association between more frequent VOCs and death and its relative impact upon overall mortality compared to other known risk factors in a contemporary adult SCA cohort.


METHODS
Two hundred sixty four SCA adults were assigned into two groups based on patient reported outcomes for emergency department (ED) visits or hospitalizations for painful VOC treatment during the 12 months prior to evaluation.


RESULTS
Higher baseline hematocrit (p = 0.0008), ferritin (p = 0.005), and HDL cholesterol (p = 0.01) were independently associated with 1 or more painful VOCs requiring an ED visit or hospitalization for acute pain. During a median follow-up of 5 years, mortality was higher in the ED visit/hospitalization group (relative risk [RR] 2.68, 95% CI 1.1-6.5, p = 0.03). Higher tricuspid regurgitatant jet velocity (TRV) (RR 2.41, 95% CI 1.5-3.9, p < 0.0001), elevated ferritin (RR 4.00, 95% CI 1.8-9.0, p = 0.001) and lower glomerular filtration rate (RR=2.73, 95% CI 1.6-4.6, p < 0.0001) were also independent risk factors for mortality.


CONCLUSIONS
Severe painful VOCs remain a marker for SCA disease severity and premature mortality in a modern cohort along with other known risk factors for death including high TRV, high ferritin and lower renal function. The number of patient reported pain crises requiring healthcare utilization is an easily obtained outcome that could help to identify high risk patients for disease modifying therapies.


BACKGROUND
ClinicalTrials.gov NCT00011648 http://clinicaltrials.gov/
Center for Cancer and Blood Disorders, Children's National Medical Center, Washington DC, United States of America ; Genomic Medicine Section, Hematology Branch, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, Maryland, United States of America.
Deepika S
DS
Darbari
Zhengyuan
Z
Wang
Minjung
M
Kwak
Mariana
M
Hildesheim
James
J
Nichols
Darlene
D
Allen
Catherine
C
Seamon
Marlene
M
Peters-Lawrence
Anna
A
Conrey
Mary K
MK
Hall
Gregory J
GJ
Kato
James G
JG
Taylor
D000328:Adult; D000755:Anemia, Sickle Cell / Q000378:metabolism / Q000401:mortality* / Q000503:physiopathology*; D008076:Cholesterol, HDL / Q000378:metabolism; D005260:Female; D005293:Ferritins / Q000378:metabolism; D006400:Hematocrit; D006801:Humans; D053208:Kaplan-Meier Estimate; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D016016:Proportional Hazards Models; D012307:Risk Factors
D008076:Cholesterol, HDL; D005293:Ferritins