Exploring the environmental determinants of sleep quality: A questionnaire-based pilot study in Indian university dormitories

We surveyed the ventilation practices, bedroom conditions, and sleep-related behaviours in naturally ventilated hostels in Kanpur, India, and related them to self-estimated sleep quality, using the Pittsburgh Sleep Quality Index (PSQI). For 70.1 % of 518 valid responses obtained from 18 to 27-year-old respondents, PSQI was above 5, indicating disturbed sleep. Sleeping with windows and doors open, both connecting to the outdoors, and morning airing were associated with lower PSQI (better sleep). Sleeping with only doors open was associated with higher PSQI (poor sleep). Use of evaporative coolers was associated with perceived disturbances and PSQI, depending on whether the windows or doors were closed or open. Although PSQI was marginally related to the use of evaporative air coolers, their use was significantly related to lower self-reported sleep latency and increased perceived environmental disturbances. The high bedroom temperatures, stuffy air and odours were frequently reported, and they were associated with higher PSQI. Those who reported more environmental disturbances also reported more disturbed sleep. Principal Component Analysis (PCA) identified two likely sources of environmental disturbance: evaporative cooler use, contributing to lower temperatures, noise, and stuffy air, and inadequate thermoregulation, leading to thermal and odour discomfort. We confirmed that the results were robust using the Monte Carlo Cross Validation (MCCV) method, splitting the data into two independent and equal groups of responses to address the problem that all dependent and independent variables were assessed by the same subjects. Future studies, including objective measurements, are recommended to verify these associations in the same settings.