Type 2 Diabetes-Related Complications Among Commercial Pilots: Aeromedical Considerations from a Retrospective Cohort

Purpose: Type 2 diabetes mellitus (T2DM) and diabetes-related complications can pose serious challenges to pilots by affecting their flight performance and professional careers. This study aims to investigate the emergence of complications in commercial pilots with T2DM through a retrospective evaluation of their aeromedical examination records. Patients and Methods: The retrospective cohort study included 59 commercial pilots who had a confirmed diagnosis of T2DM in year 2012, whereas pilots without such diagnosis within that year were excluded from the study. Their examination records involving the first diagnosis of T2DM prior to 2012 and all subsequent records from 2013 to 2021 were comprehensively analyzed. Data included demographic information, smoking status, age of diabetes and complication onset, certain biochemical markers, complications, and aeromedical certification processes. Estimated glomerular filtration rate (eGFR) values were calculated in each record using the CKD- EPI equation, with chronic kidney disease determined as two consecutive eGFR measurements being < 60 mL/min/1.73 m 2 . Examination intervals varied from 6 to 12 months based on aeromedical regulations. Statistical analyses were performed using proper comparative tests, and multivariate logistic regression was employed to identify factors linked to complications. Results: Of the 59 pilots, 28 (47.5%) had at least one complication, such as coronary artery disease (CAD), retinopathy, stroke, or diabetic kidney disease (DKD), with 14 of them diagnosed retrospectively by eGFR measurements. The prevalence of smoking was 30.5%, with 77.78% of them developing complications, indicating a significant relationship (p=0.004). The mean age at the diagnosis of T2DM was 50.16± 6.62, while complications occurred at 58.64± 5.69 years. No significant difference was found in the age of T2DM onset between pilots with complications and those without. Conclusion: This study identified a strong association between smoking and diabetes-related complications, demonstrated a high rate of complications —primarily CAD and DKD— in pilots with T2DM, and underscored the importance of periodical examinations in detecting subclinical conditions. Routine eGFR measurement was also shown to be essential for the early detection of DKD diagnosis. Keywords: diabetes mellitus, commercial pilots, complication of diabetes, aeromedical examination, flight safety, early diagnosis, diabetic kidney disease