Omega-3 fatty acids in sickle cell anemia

To the editor:

A study done a decade ago found that treatment of sickle cell anemia with ω-3 fatty acids reduced the frequency of pain episodes from 7.8 to 3.8 per year (P < .01).¹  However, only 10 patients completed that study, and the finding received scant attention. A more recent study of 140 Sudanese patients (including children and adults with ages ranging from 2 to 24 years) found that ω-3 fatty acids reduced the frequency of pain episodes from a median of 4.6 to 2.7 per year (P < .01) and of pain requiring hospitalization from a median of 1 to 0 per year (P < .0001). They also reduced the frequency of severe anemia from 16.4% to 3.2% per year (P < .05) and of transfusion from 16.4% to 4.5% per year (P < .03).²  The theoretical ability of ω-3 fatty acids to ameliorate aspects of the pathophysiology of sickle cell anemia—the coagulopathy,¹  the increased red blood cell adhesiveness,^2,3  the inflammation,⁴  and the NO insufficiency⁵ —adds credence to the empiric observations.

However, the subjective nature of judgments regarding pain and the need for hospital care and the phenotypic heterogeneity of sickle cell disease⁶  are reasons to delay accepting the universality of these studies. A firm recommendation about treatment of the millions of individuals with sickle cell anemia should be supported by a larger multicenter study.

Nevertheless, funding and then organizing and completing the needed study will take years. Thus, clinicians must juxtapose the possibility that a generation of patients with sickle cell anemia might be helped by ω-3 fatty acids (which appear to have negligible toxicity) against the possibility that ω-3 fatty acids might prove to be no better than a placebo in a large, controlled, double-blind multicenter study.