Background The Global Lung Initiative 2012 (GLI‐2012) spirometry equations are multi‐ethnic equations that cover all ages between 3 and 95. However, there is a need to evaluate the suitability of these equations to a sample of Middle Eastern adolescents prior to being applied in clinical practice. The aim of this study is to evaluate the suitability of GLI‐2012 equations and two regional equations to a sample of Jordanian adolescents. Methods Spirometric measures were collected from 1036 healthy 14 to 17‐year‐old Jordanian children. z‐scores, predicted values, percent predicted values, and frequency of measures below lower limit of normal (LLN) were calculated for each adolescent using the studied equations. Results The means of z‐scores produced by GLI‐2012 equations for Caucasians in forced expiratory volume in the first second (FEV1), forced vital capacity (FVC), FEV1/FVC% and mid forced expiratory flow (FEF25‐75) for boys were 0.12, −0.06, 0.34 and 0.09, respectively, while for girls they were −0.09, −0.16, 0.19 and −0.05, respectively. The mean of z‐scores produced by GLI‐2012 Other or Mixed equations in FEV1, FVC, FEV1/FVC% and FEF25‐75 for boys were 0.74, 072, 021 and 0.33, respectively, and for girls were 0.53, 0.56,0.02 and 0.2, respectively. The frequency of measures below LLN as produced by GLI 2012 for Caucasians were significantly different from the expected 5% in FEV1 and FEF25‐75 in boys only, whereas Other or Mixed produced frequencies significantly different from the expected 5% in most of the parameters. Conclusion Spirometry reference equations formulated for Jordanian adolescents may improve the diagnosis and treatment of asthma in Jordan.

Background: Type 2 diabetes mellitus (T2DM) is a chronic condition with an impairing effect on multiple organs. Numerous respiratory disorders have been observed in patients with T2DM. However, T2DM e ect on pulmonary function is ff inconclusive. Aims: In this study, we investigated the effect of T2DM on respiratory function and the correlation of glycemic control, diabetes duration and insulin intake. Methods: 1500 patients were recruited for this study, 560 having T2DM for at least a year were included in the final data, in addition to 540 healthy volunteers. Forced expiratory volume in one second (FEV1), forced vital capacity (FVC), forced expiratory flow at 25-75% (FEF 25-75%), as well as FEV1/FVC ratio values were measured. Results: A two-sample t-test showed that z-scores produced by Al-Qerem et al.’s equations for FEV1, FVC, and FEF 25-75% were significantly lower for the T2DM group than the control group (p < 0.01). FEV1/FVC ratio in T2DM group were significantly higher (p < 0.01). Multiple linear regression analysis found that glycemic control represented by HbA1c as well as disease duration were negatively associated with pulmonary function (p < 0.01). However, insulin intake was found to have no significant correlation with the pulmonary function. Conclusion: T2DM was linked to reduced pulmonary function and was consistent with a restrictive ventilation pattern. HbA1c as well as disease duration were independent risk factors for reduced pulmonary function.