Sleep Health Across Geographically Diverse Regions of India: A Multisite Online Cross-Sectional Study

IntroductionSleep is a modifiable determinant of cardiometabolic and mental health that remains poorly characterised in India outside urban and occupational cohorts, and almost no data exist for island and climatically distinct regions.This study estimated the prevalence of poor sleep quality and inadequate sleep duration among adults at four purposively selected, climatically contrasting Indian sites and examined their sociodemographic, lifestyle, environmental, and psychosocial correlates. MethodsA multicentric cross-sectional online survey was conducted between May and August 2026 among adults aged 18 years and above in the Andaman & Nicobar Islands (lead site), Delhi, Jammu & Kashmir, and Rajasthan, with additional convenience responses from other Indian states and union territories.A structured, self-administered questionnaire captured sociodemographic, lifestyle, occupational, and environmental variables, together with the Pittsburgh Sleep Quality Index (PSQI), Epworth Sleepiness Scale (ESS), Patient Health Questionnaire-9 (PHQ-9), and Perceived Stress Scale-10 (PSS-10).Poor sleep quality was defined as a global PSQI score above five.Associations were examined using chi-square or Fisher's exact tests, Kruskal-Wallis tests, Spearman's correlation, and multivariable logistic regression. ResultsOf 863 responses received, one from a respondent residing outside India was excluded, leaving 862 for analysis (mean age 25.8 ± 9.0 years; 56.1% female; 66.8% students).The mean global PSQI score was 6.55 ± 3.48; 475 respondents (55.1%, 95% CI 51.8-58.4)had poor sleep quality, and 641 (74.4%) reported sleeping fewer than seven hours on a typical night.Excessive daytime sleepiness (ESS ≥ 10) was present in 236 (27.4%), and depressive symptoms (PHQ-9 ≥ 10) were present in 257 (29.8%); 270 (31.3%) endorsed at least "several days" on the PHQ-9 item concerning thoughts of being better off dead or of self-harm.Poor sleep quality ranged from 40.5% in Rajasthan to 60.8% in Jammu and Kashmir, a difference of borderline statistical significance (p = 0.055).Among the 655 respondents who completed the environmental module, poor sleep quality increased in a graded fashion with self-reported heat/humidity disturbance (43.6% to 75.6%, p < 0.001) and nocturnal insect disturbance (50.3% to 84.2%, p = 0.005); these were unadjusted associations.Poor sleep quality was more frequent among those with depressive symptoms (80.9% versus 44.1%) and excessive daytime sleepiness (76.7% versus 47.0%; both p < 0.001).After adjustment, shift or irregular work (adjusted OR 2.15, 95% CI 1.15-4.01)and higher perceived stress (aOR 1.93 per SD, 95% CI 1.58-2.36)remained independently associated with poor sleep quality.No association was observed with self-reported hypertension, diabetes, or obesity. ConclusionsMore than half of this predominantly young, student-heavy online sample reported poor sleep quality, which was independently associated with irregular work schedules and perceived stress and, in unadjusted analyses, with self-reported heat, humidity, and insect disturbance.Because sampling was nonprobabilistic, these estimates are indicative rather than representative of Indian adults.The findings support further population-based research using objective environmental measures on sleep health in island and climatically challenging regions, as well as the integration of sleep screening into mental health and non-communicable disease (NCD) programmes.