0556 Polysomnographic Findings in Heavy Machinery Operators Working in High-Altitude Mining Sites with Suspected Sleep-Related Breathing Disorders

Abstract Introduction High-altitude mining is a major economic activity in countries such as Peru. Mining camps are located in remote areas and require rotational work systems in which operators alternate between day and night shifts under demanding environmental conditions. Exposure to hypobaric hypoxia, prolonged work cycles, and irregular sleep schedules predisposes workers to fatigue and excessive daytime sleepiness. Previous research has reported fatigue in 20–40% of high-altitude miners, and sleepiness has been linked to up to 65% of driving-related incidents. These findings highlight the need to evaluate sleep disorders and fatigue-related risks in this work setting. Methods Thirty-eight heavy machinery operators who generated sleepiness alerts while driving at a mining camp located at 4,300 meters above sea level were evaluated. Workers with recurrent alerts detected by a semi-automated fatigue-monitoring system underwent respiratory polygraphy onsite and were later referred to a sea-level Sleep Unit for complete polysomnography. Clinical variables predictive of obstructive sleep apnea (OSA) were analyzed and adjusted for age, sex, and altitude of residence (>3000 m vs. sea level). Results Thirty-three valid clinical records were included. OSA was diagnosed in 17 workers (51.5%): 47.1% mild, 41.2% moderate, and 11.8% severe. CPAP therapy was prescribed for 13 patients; one received a mandibular advancement device, and three were managed expectantly. Compared with non-OSA individuals, patients with OSA had higher BMI (29.8 vs. 26.1 kg/m2), higher Epworth scores (11.2 vs. 7.8), and higher STOP-BANG values (4.9 vs. 3.2). STOP-BANG (OR 1.45), Epworth (OR 1.21), and BMI (OR 1.18) were significantly associated with OSA. After adjustment for altitude, STOP-BANG (OR 1.52) and BMI (OR 1.28) remained significant predictors, whereas Epworth did not. Conclusion High-altitude machinery operators with repeated sleepiness alerts showed a high prevalence of OSA, with most requiring treatment. STOP-BANG and BMI were the strongest predictors of OSA after adjusting for altitude of residence. These findings support systematic screening for sleep disorders in high-altitude mining environments. Support (if any)