en Pediatrics پژوهشي Research <span style="font-size:10pt"><span style="line-height:200%"><span sans-serif="" style="font-family:Calibri,"><b><span style="font-size:12.0pt"><span style="line-height:200%"><span new="" roman="" style="font-family:" times="">Background and objectives: </span></span></span></b><span style="font-size:12.0pt"><span style="line-height:200%"><span new="" roman="" style="font-family:" times="">Major &beta;-thalassemia refers to a severe form of &beta;-thalassemia in which, patients need blood transfusions from an early age. Iron overload is an important and long-term complication of repeated blood transfusions. The lungs are one of the sites of iron deposition; therefore, it is essential to investigate lung dysfunction due to iron deposition. This study evaluates pulmonary function tests in &beta;-thalassemia major patients receiving regular blood transfusions and chelation therapy.</span></span></span></span></span></span><br> <span style="font-size:11pt"><span style="line-height:200%"><span sans-serif="" style="font-family:Calibri,"><b><span style="font-size:12.0pt"><span style="line-height:200%"><span new="" roman="" style="font-family:" times="">Methods: </span></span></span></b><span style="font-size:12.0pt"><span style="line-height:200%"><span new="" roman="" style="font-family:" times="">In this cross-sectional descriptive study, 120 patients (68 males and 52 females) with &beta;-thalassemia major aged 6 to 41 years who underwent blood transfusion at Bahrami Children&#39;s Hospital (Tehran, Iran) in 2021 were enrolled. The patients underwent hematological and pulmonary function tests on the day of transfusion. Association between pulmonary function tests and demographic and laboratory data was investigated.</span></span></span></span></span></span><br> <span style="font-size:11pt"><span style="line-height:200%"><span sans-serif="" style="font-family:Calibri,"><b><span style="font-size:12.0pt"><span style="line-height:200%"><span new="" roman="" style="font-family:" times="">Results: </span></span></span></b><span style="font-size:12.0pt"><span style="line-height:200%"><span new="" roman="" style="font-family:" times="">Spirometry indices including forced expiratory volume in the first second (FEV1), forced vital capacity (FVC), and forced expiratory volume to forced vital capacity ratio (FEV1/FVC) were 86.14%&plusmn;9.9, 87.86%&plusmn;11.19, and 98.78%&plusmn;10.97, respectively. In this study, the percentages of FEV1 and FEV1/FVC of patients older than 23 years were significantly lower compared to patients younger than 23 years. Moreover, a significantly lower FEV1/FVC ratio was seen in patients with higher body mass index and a serum ferritin level above 3,325 ng/dl. The most common impairment (19%) was a restrictive pattern.</span></span></span></span></span></span><br> <span style="font-size:11pt"><span style="line-height:200%"><span sans-serif="" style="font-family:Calibri,"><b><span style="font-size:12.0pt"><span style="line-height:200%"><span new="" roman="" style="font-family:" times="">Conclusion: </span></span></span></b><span style="font-size:12.0pt"><span style="line-height:200%"><span new="" roman="" style="font-family:" times="">Age is inversely associated with FEV1 and FEV1/FVC ratio. Moreover, higher body mass index and serum ferritin levels are significantly associated with reduced FEV1/FVC ratio. </span></span></span></span></span></span><br> &nbsp; Thalassemia, Respiratory Function Tests, Blood Transfusion, Iron Overload 21 30 http://jcbr.goums.ac.ir/browse.php?a_code=A-10-309-1&slc_lang=en&sid=1 Alireza Shafiei ar.shafii@gmail.com 10031947532846003873 10031947532846003873 No Division of Allergy and Clinical Immunology, Department of Pediatrics, Bahrami Hospital, Tehran University of Medical Sciences, Tehran, Iran Mohammad kajiyazdi mkajiyazdi50@gmail.com 10031947532846003874 10031947532846003874 No Division of Pediatric Hematology and Oncology, Department of Pediatrics, Bahrami Hospital, Tehran University of Medical Sciences, Tehran, Iran Mohammadali Ehsani maehsani@gmail.com 10031947532846003875 10031947532846003875 No Division of Pediatric Hematology and Oncology, Department of Pediatrics, Bahrami Hospital, Tehran University of Medical Sciences, Tehran, Iran Elham Shahgholi eshahgholi@gmail.com 10031947532846003876 10031947532846003876 No Division of Pediatric Hematology and Oncology, Department of Pediatrics, Bahrami Hospital, Tehran University of Medical Sciences, Tehran, Iran Saman Aghabekloo saman.beglou@gmail.com 10031947532846003877 10031947532846003877 Yes Department of Pediatrics, Bahrami Hospital, Tehran University of Medical Sciences, Tehran, Iran