Frequency of Vaso-Occlusive Episode and Predictors Among Children with Sickle Cell Anaemia at Mulago National Referral Hospital, Uganda

Abstract Background Sickle cell anaemia (SCA) involves complications, with the most frequent and severe being painful vaso-occlusive crises (VOCs). VOCs often require emergency department visits for pain relief. However, we lack information about the burden of these crises in our context. We determined the frequency and factors associated with VOCs in young children in a tertiary institution in Uganda. Methods A cross-sectional study design was employed. Data was collected using structured questionnaire from 406 children with SCA aged 6 months – 15 years presenting to acute care unit of Mulago National Referral Hospital, Kampala, Uganda between February and May 2023. Results A total of 406 children were recruited, most of whom were in the 6-11yrs (44.8%) age range. The prevalence of VOC was 74.38% (95% CI: 70.36–79.02). Prevalence was highest among older age groups12-15yrs (82.6%). Younger age (< 6 years) was associated with reduced odds of VOC compared to older children (aOR 0.67, 95% CI: 0.23–0.89, p = 0.03). Caregiver provision of adequate oral fluids was also protective, associated with 10% lower odds of VOC (aOR 0.90, 95% CI: 0.17–0.98, p = 0.04). Clinical interventions showed particularly strong protection: hydroxyurea therapy reduced VOC odds by 46% (aOR 0.54, 95% CI: 0.33–0.86, p < 0.01), while penicillin prophylaxis showed a 69% reduction (aOR 0.31, 95% CI: 0.18–0.45, p = 0.02). Conclusion Almost three-quarters of children with SCA seeking acute care had VOCs. Protective factors included hydroxyurea therapy, penicillin prophylaxis, adequate oral fluids, and younger age. These findings highlight the urgent need to scale up evidence-based interventions like hydroxyurea and penicillin while strengthening caregiver education on preventive measures in resource-limited settings. Clinical Trials Registration: Not applicable