PURPOSE: Pulmonary hypertension (PH) is a source of significant morbidity and mortality in patients with hemolytic diseases. PH and atherosclerosis are both diseases of the vasculature, sharing many similarities. We studied lipid levels, a known risk factor for atherosclerosis, in patients with sickle cell disease and examined the relationship to PH.
METHODS: Sixty-nine adult patients with sickle cell disease (SS and SC) or sickle cell/beta-thalassemia (SβThal) followed in a specialized sickle cell and thalassemia center were evaluated for echocardiographic data to determine the presence of PH. Data regarding lipid levels (total cholesterol, triglycerides, and high- (HDL) and low-density lipoprotein (LDL)) and markers of hemolysis were retrospectively collected; differences between individuals with or without PH were analyzed using the two-tailed t-test. PH was defined as a tricuspid regurgitant jet velocity ≥ 2.5 m/s and/or a right ventricular systolic pressure ≥ 40mmHg, with no left ventricular systolic dysfunction on echocardiography. All laboratory and echocardiographic data collected were performed in the outpatient setting between January 2009 and May 2010.
RESULTS: Of the initial 69 subjects, 33 had complete outpatient laboratory and echocardiographic data and were included in the analysis. Of the 33, 8 were found to fulfill criteria for PH, while 25 did not. Six of the 8 subjects with PH (75%) and 16/25 subjects without PH (64%) were of the SS genotype. When analyzing total cholesterol, triglycerides, HDL, and LDL between the PH and non-PH groups, no significant difference was found (p= 0.46, 0.94, 0.15, 0.83 respectively). There was also no significant difference in age between the two groups (p= 0.69). When the analysis was restricted to the SS genotype, the results remained non-significant.
CONCLUSION: There was no significant difference in mean lipid levels in those with and without PH in our cohort of patients. The lack of significance may be due to the small size of our cohort.
CLINICAL IMPLICATIONS: Studying possible risk factors in the development of PH may aid in the prevention and treatment of PH in sickle cell disease.
DISCLOSURE: Ahmad Abdelwahed, No Financial Disclosure Information; No Product/Research Disclosure Information