Analysis of Pulmonary Function in Children With Sickle Cell Anemia

In a new study, researchers found that pediatric patients with sickle cell anemia (SCA) showed signs of impaired pulmonary function compared with control individuals without SCA. The study was a systematic review and meta-analysis conducted by a research team led by Amar Taksande, MD, of Jawaharlal Nehru Medical College in Wardha, Maharashta, India, with results reported in the PanAfrican Medical Journal.

It has been known that obstructive and restrictive pulmonary conditions are associated with morbidity and mortality in pediatric patients with SCA. “However, the pattern of abnormal lung function in SCA has been disputed,” Dr Taksande and colleagues wrote. They undertook an analysis of the literature to compare patterns of pulmonary function tests (PFTs) in children with and without SCA, and to additionally examine whether hydroxyurea treatment impacted PFT results for children with SCA.

The researchers obtained information for their analysis from studies found through the Cochrane Library, PubMed, EMBASE, Scopus, and Web of Science databases, with the most recent search conducted on August 20, 2020. Search terms included words or phrases related to respiratory or pulmonary function and sickle cell anemia. The analysis included reports that involved case-control studies including PFT in patients with SCA and in control individuals. From a total of 707 identified articles, articles related to 9 eligible and relevant studies were evaluated in the meta-analysis, involving 788 children with SCA and 1101 control individuals.

The researchers calculated pooled mean differences between patients with or without SCA for PFT results, and these included data from 4 studies. Overall, children with SCA showed lower PFT for the evaluated parameters than individuals without SCA did. However, the authors considered the results to be significant for only force expiratory volume in 1 second (FEV1) and for forced vital capacity (FVC).

For FEV1, the difference was -12.67 (95% CI, -15.41 to -9.94; P <.00001). For FVC, the difference was -11.69 (95% CI, -14.24 to -9.14; P <.00001). For the FEV1/FVC ratio, the difference was -1.90 (95% CI, -4.32 to 0.52; P =.12). Peak expiratory flow rate showed a difference of -3.36 (95% CI, -6.69 to -0.02; P =.05). Total lung capacity showed a difference of -7.35 (95% CI, -14.97 to 0.27; P =.06), and carbon monoxide diffusing capacity showed a difference of -4.68 (95% CI, -20.64 to 11.29; P =.57). Heterogeneity of results was considered moderate for FEV1 and FVC parameters and higher for other parameters.

The researchers found no significant difference in FEV1 and FVC between children given hydroxyurea compared with those who did not receive it. The FEV1/FVC ratio was significantly different in this comparison, but this analysis showed high heterogeneity.

The researchers concluded that FEV1 and FVC are generally lower for children with SCA than for those without this condition. They also considered PFT evaluations to be a potentially important tool for screening and monitoring of patients who may be at high risk for pulmonary complications.

Reference

Taksande A, Jameel PZ, Pujari D, Taksande B, Meshram R. Variation in pulmonary function tests among children with sickle cell anemia: a systematic review and meta-analysis. Pan Afr Med J. 2021;39:140. doi:10.11604/pamj.2021.39.140.28755