Sleep Quality Among Pilgrims at High Altitude: A Cross-Sectional Study From Gosaikunda Lake, Nepal (4380 m)

Introduction Nepal is a touristic country; globally, many people visit Nepal for mountaineering, trekking, sightseeing, and pilgrimages. Gosaikunda, located at an elevation of 4380 m (14,370 ft) in the Rasuwa district, Nepal, is a popular pilgrimage site. At high altitudes, hypobaric hypoxia is the primary cause of sleep disturbances and is characterized by difficulty falling asleep, frequent nighttime awakening, difficulty returning to sleep, and waking up earlier in the morning than desired, ultimately resulting in a reduction in total sleep duration and quality. Objective The primary objective of this study was to evaluate the quality of sleep patterns of pilgrims while undergoing acute high-altitude exposure on their journey to Gosaikunda, Nepal, which is a pilgrimage site situated at an altitude of 4380 meters (14,370 feet) above sea level. Methodology A cross-sectional descriptive study from August 7 to 14, 2022, was conducted among Gosaikunda pilgrims who visited the sacred lake in Rasuwa district in Nepal at an altitude of 4380 m, where weather is unpredictable and adverse climatic events are prevalent. The subjective sleep quality was evaluated by using the Athens Insomnia Scale (AIS). Individual participants rated each item (sleep symptoms) as 0 to 3, 0 = no problem, 1 = slight problem, 2 = marked problem, and 3 = very marked or no sleep at all. The total range of the score is 0 to 24, with a cutoff point score ≥ 6 being considered poor sleep. Results Out of 229 participants, 42 (18%), 24 (11%), and three (1%) of them experienced mild, moderate, and severe insomnia, and 160 (70%) had no sleep disturbances. Based on the Athens Insomnia Scale cutoff points, 69 (30.13%) had a score of ≥ 6, indicative of insomnia, and 160 (69.86%) had a score of less than 6, suggestive of no insomnia. Daytime sleepiness was the most common subjective sleep issue among the pilgrims suffering from insomnia (40, 57.97%) and no insomnia (96, 60%). The majority of pilgrims, 207 (99.12%), stayed overnight while ascending at Gosiakunda (4380 meters). The mean body mass index (BMI) in kg/m² of pilgrims suffering from insomnia and those not suffering from insomnia was 25.29±5.3 and 24.58±4.47, respectively, with a P-value greater than 0.05. The mean age among pilgrims suffering from insomnia and pilgrims who didn't was 41.64±13.39 and 41.64±13.44, respectively, with a P-value greater than 0.05. The majority of the pilgrims took an average of two days to reach Gosaikunda Lake, of which 207 (99.12%) remained at altitude for one night and 22 (0.96%) stayed for more than one night. Conclusion Acute exposure to high altitude results in frequent arousal due to hypobaric hypoxia, which in turn causes pilgrims to feel mentally and physically fatigued and somnolent due to the poor sleep they experience. An elevated BMI, advanced age, and male sex were associated with poor sleep quality after acute altitude exposure. Further research is needed to better understand the mechanisms underlying these associations and to develop effective interventions to improve sleep quality during rapid ascent.