Study objectives: To determine the longitudinal associations of long-time mobile phone use (LTMPU) with sleep disturbances and mental distress in a prospective cohort of technical college students.
Methods: A total of 4333 (response rate: 91.5%) and 3396 (response rate: 78.4%) participants were recruited at baseline and 8-month follow-up, respectively. Data were collected by a set of questionnaires including socio-demographics, lifestyle practice, duration of mobile phone use per day, sleep patterns on weekdays and weekends, as well as Insomnia Severity Index, Epworth Sleepiness Scale, reduced Morningness-Eveningness Questionnaire, Beck Depression Inventory, and Zung Self-Rating Anxiety Scale. LTMPU was defined as using mobile phone ≥4 hours/day.
Results: At baseline, 23.5% (n = 1020) of the participants reported using mobile phone ≥ 4 hours/day. LTMPU at baseline was positively associated with the new incidences (range, adjusted odds ratio 1.31-1.53) of a series of the sleep disturbances and mental distress at follow-up. The discontinuation of LTMPU was associated with an amelioration of the risks of most of these problems. Cross-lagged analyses revealed bidirectional associations of the duration of mobile phone use with poor sleep and mental health outcomes.
Conclusions: LTMPU predicts the new incidences of most sleep disturbances and mental distress, while discontinuation of LTMPU is associated with amelioration of these problems. Moreover, there are bidirectional associations between the duration of mobile phone use and various sleep and mental outcomes. These findings highlight the critical role of prevention and early recognition of excessive mobile phone use and their accompanied mental and sleep problems.