Prevalence and factors associated with abnormal lung function in children aged 6 upto 18 years attending the sickle cell clinic at Mulago national referral hospital

Abstract

Background: Pulmonary complications in children with sickle cell disease (SCD) is common and is associated with a significant morbidity and mortality. However, despite the high burden of SCD in Uganda, there is a scarcity of data on the prevalence and factors associated with abnormal lung function among children living with SCD in Uganda. Objective: To determine the prevalence and factors associated with abnormal lung function among children living with SCD in Uganda. Method: A cross-sectional study was conducted at the sickle cell clinic (SCC) of Mulago National Referral Hospital (MNRH). Children aged 6 to 18 years were screened for eligibility. A questionnaire was administered, and clinical history and physical examination done. For eligible participants, spirometry was performed. Forced vital capacity (FVC), forced expiratory volume in one second (FEV1) and the FEV1/ FVC ratio determined to diagnose abnormal lung function. Results: A total of 427 participants were screened, and 332 were considered eligible. The mean age (standard deviation, [SD]) was 11.7 ±3.4 year, and 184 (55.4%) were female. The prevalence of abnormal lung function was 37.9% (126/332) (95% confidence interval (CI): 32.9 — 43.3). Of the 126 participants with abnormal lung functions, 67 (53.2%) had restrictive, 57 (45.2%) obstructive and 2 (1.6%) mixed patterns. The factors associated with abnormal lung functions were; serum lactate dehydrogenase (LDH) level > 600UL [ adjusted odds ratio (aOR): 2.9, 95% CI: 1.2 — 7.4, p=0.024], history of acute chest syndrome (aOR: 2.59, 95% CI: 1.05 — 6.36, p=, 0.041), wasting (aOR167,95%CI: 1.01- 2.79, p= 0.049), use of charcoal for cooking (aOR 2.01, 95% CI: 0.95 -3.77, p= 0.031) and SpO2 (aOR 2.83, 95%CI: 1.55- 5.19, p<0.001). Conclusion: Over one-third of the participants had an abnormal lung function. Routine screening may be considered in patients with a history of acute chest syndrome, elevated xii LDH, wasting and hypoxemia. Increasing serum LDH levels may be further investigated as a biomarker of abnormal lung function in this population.