Clinical and biological associations linked to the use of hydroxyurea in patients with homozygous sickle cell disease (SS) in Conakry, Guinea: a comparative study

Sickle cell disease is a major public health problem in Guinea, where access to disease-modifying therapy remains limited. Hydroxyurea is the reference treatment for severe forms, but data on its use in Guinean patients are scarce. Our aim was to evaluate the clinical and biological results associated with hydroxyurea use in patients with homozygous sickle cell disease (SS) followed at the two university hospitals of Conakry. We conducted a cross-sectional, descriptive and analytical study over six months (1 October 2025 to 31 March 2026) in the haematology departments of the Donka and Ignace Deen University Hospitals. In total, 210 SS patients were consecutively included and divided into two groups: 102 patients (48.6%) receiving hydroxyurea for at least six months and 108 patients (51.4%) not receiving hydroxyurea, forming the comparison group. Clinical events over the previous six months and haematological parameters were compared between the groups. Continuous variables were compared using the Mann–Whitney test and qualitative variables using the Pearson chi-square test or Fisher’s exact test; a two-sided p < 0.05 was considered significant. The mean age was 22 years (range 1–48), with a female predominance (sex ratio 0.9). Compared with the untreated group, patients receiving hydroxyurea had significantly fewer vaso-occlusive crises, hospitalisations, transfusions, and acute and chronic complications (all p < 0.001). Biologically, hydroxyurea was associated with higher fetal haemoglobin ( p < 0.001) and mean corpuscular volume ( p = 0.004), as well as lower leucocyte and platelet counts (both p < 0.001). Headache was the most frequent adverse effect (39.2%). In a low-income setting, hydroxyurea is associated with a more favourable clinical and biological course and represents an accessible therapeutic option for patients with SS.