Background Sickle cell disease is a genetic disorder associated with lifelong symptoms of anemia, vaso-oclusive crisis and organ damage. Pulmonary complications and declining lung functions are contributors to morbidity and mortality. Determination of lung functions can enable early diagnosis and institution of appropriate intervention. Methods and findings  A cross sectional study done at Jaramogi Oginga Odinga Teaching and Referral Hospital in Kisumu, Kenya, to determine the prevalence, patterns, and the factors associated with abnormal lung functions in children and adolescents aged 6-17 years with confirmed diagnosis Sickle Cell Disease. A total of 138 participants were recruited. A structured data collection tool was used to collect Socio-demographics and clinical characteristics. The spirometry was done using NDD Easy-On PC spirometer and results entered into database, cleaned and analyzed for proportions, frequency, mean, range and odds ratio at 95% confidence level. Females were 65(47%), males 73(53%), and the mean age was 10.99 years with SD of 3.15. A total of 79(57%) were from rural and fuel used was fired wood 41%. Hospital admission were 84(61%), vaso-oclusive crisis 104 (75%), acute chest syndrome 61(44%) and blood transfusions 56(40%) in the last 12 months. Prevalence of abnormal lung functions was 28 % (39), restrictive pattern 26(67%) and obstructive pattern 13(33%). Urban setting (OR 24.101 p value 0.163), being female (OR 18.911 p value 0.069), and blood transfusion (OR 11.683 p value 0.195) had high odds ratio while, stable hydroxyurea use (OR 0.525 p value 0.678) and hospital admission (OR 0.048 p value 0.121) had low odds ratio, but not statistically significant. Conclusion One third had abnormal lung function mostly restrictive followed by obstructive pattern. Residence in urban setting, being female and blood transfusion had high odds ratio, while stable hydroxyurea use and hospital admission had low odds ratio but no statistically significant

The authors have declared no competing interest.

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