Abstract
BACKGROUND:
The survival of sickle cell patients is limited as compared to the general population. The major morbidity and mortality comes from sickle cell complications including cardiovascular disease, renal failure, infections and thrombosis (Manci Br J Haematol 2013). However, literature is conflicting about risk for malignancies in this population and remains to be investigated by larger studies. Our retrospective study is aimed at studying the prevalence of different malignancies in a large cohort of hospitalized sickle cell patients in the year 2014 using the National Inpatient Sample (NIS).
METHODS:
Study Population:
We identified hospitalized sickle cell patients in NIS using ICD-9 codes (282.5,282.6X -282.6X) for year 2014. We also identified the various malignancies through ICD-9 codes and studied the prevalence of individual malignancies in hospitalized sickle cell patients (SCD/cases) compared to a matched cohort of hospitalized patients with no sickle cell disease (No SCD/controls).
Statistical Analysis:
The 1:N Case-Control Matching Macro (Parsons LS et al SUGI 29) was used to match cases with controls with respect to potential confounders including age, race, gender in the ratio of 1:4. Chi Square was used to determine the difference in the proportions of individual malignancies between the two groups. P value <0.05 was considered statistically significant. All analyses were performed using SAS 9.4.
RESULTS:
We identified 117,405 hospitalized sickle cell patients in the NIS database who were matched to 469,620 controls (Table 1). A total of 1890 malignancies were found in sickle cell cohort. The prevalence of malignancies in hospitalized sickle cell patients was 1.6% as compared to 4.6% in controls (OR 0.34; range:0.30-0.38). The prevalence of all studied malignancies including hematological malignancies was lower in hospitalized sickle cell patients as compared to a matched population of hospitalized patients with no sickle cell disease (Table 2).
CONCLUSION:
Our study showed a lower prevalence of both solid tumors and hematological malignancies in patients with sickle cell disease as compared to matched cohorts. Future prospective cohort studies are needed to evaluate the risk of malignancies in sickle cell anemia and identify if any protective mechanisms exist against the development of malignancy in this patient population.
No relevant conflicts of interest to declare.
