NEW DELHI: Nearly one in four school-going adolescents in Central Delhi was found to be sleep deprived, with poor sleep associated with lower academic performance and higher depressive symptoms, according to a study published in the Indian Journal of Community Medicine.
The study found that 326 of 1,452 adolescents, or about 22.5 per cent, were sleep deprived. Those affected recorded average academic grades of 64 per cent, compared with 67 per cent among their peers who were not sleep deprived.
The study covered adolescents aged 12 to 18 years, with an average age of 14.18 years.
The participants were drawn from government, government-aided and private schools in Central Delhi, with boys and girls equally represented.
The study was conducted by researchers from Sir Ganga Ram Hospital, the National Health Systems Resource Centre, the ICMR-Dr AS Paintal Distinguished Scientist Chair under the Ministry of Health and Family Welfare, and the Armed Forces Medical College. It was published in May 2026.
The researchers used standardised questionnaires to assess sleep quality, depressive symptoms, cognitive function and sleep-related habits. They also examined academic performance, school attendance, body mass index, socioeconomic status and family type.
Sleep deprivation was assessed using the Pittsburgh Sleep Quality Index, with a global score above five considered indicative of poor sleep quality. The researchers also referred to insufficient sleep as getting less than eight hours of sleep a night.
The analysis showed that sleep deprivation was significantly associated with academic performance. Students with sleep deprivation had average grades of 64 per cent, compared with 67 per cent among those without it.
Daytime sleepiness was also reported by a substantial proportion of students. About 48.3 per cent said they had difficulty staying awake at least once a week, while 6 per cent experienced such difficulty three or more times a week, according to the study.
The study also found a particularly strong link between sleep deprivation and depressive symptoms. About 60 per cent, or 912 adolescents, reported depressive symptoms, including 32.9 per cent with mild symptoms and 27 per cent with moderate-to-severe symptoms.
After accounting for several other factors, adolescents with depression had 3.51 times higher odds of sleep deprivation than those without depression.
The researchers also found a moderate positive correlation between poorer sleep quality and greater depressive symptoms.
Sleep hygiene also emerged as an important factor. Better sleep-hygiene scores were associated with lower odds of sleep deprivation, with an adjusted odds ratio of 0.441 for every unit increase in the sleep-hygiene score.
According to the study, the correlation analysis showed that poorer sleep quality was linked with poorer sleep-hygiene practices, while better sleep hygiene was associated with fewer depressive symptoms.
The researchers said these findings point to behavioural factors as an important area for intervention.
The researchers also examined cognitive functioning. Nearly 66 per cent, or 999 adolescents, were classified as having poor cognitive function according to the study's assessment. However, sleep deprivation itself was not significantly associated with cognitive scores.
The study also looked at family background. Nearly 73.2 per cent of the adolescents lived in nuclear families, while the observed prevalence of sleep deprivation was 21.2 per cent among those from nuclear families and 27.6 per cent among those from joint families.
However, family type was not a statistically significant independent factor after adjustment for other variables. The adjusted analysis found an odds ratio of 0.770 for joint families compared with nuclear families, with a p-value of 0.145.
Socioeconomic background was also examined. The largest groups were adolescents from lower-middle-class families, at about 46.3 per cent, and upper-lower-class families, at 38.2 per cent. Socioeconomic class was not significantly associated with sleep deprivation but was significantly associated with cognitive function.
The researchers highlighted that more than 80 per cent of participants came from lower-middle- or upper-lower socioeconomic groups. They said factors such as noise, crowded living conditions and caregiving responsibilities could affect sleep and academic engagement, although these factors were not directly measured.
Physical health was another area examined. Nearly half of the adolescents were classified as thin, while around 8 per cent were overweight or obese. However, body mass index categories did not show a significant association with sleep deprivation in the adjusted analysis.
The researchers said sleep problems could also be influenced by lifestyle and environmental factors, including irregular routines and screen exposure.
They said the findings highlight the need for school-based measures focusing on sleep hygiene and mental health. They suggested involving parents and teachers to reinforce regular sleep routines and improve awareness of the relationship between sleep, learning and well-being.