Association between mobile phone use and incidence of dementia: A prospective cohort study using the UK Biobank

Introduction: The rapid growth in mobile phone use has led to public concern about its potential effects on the risk of dementia. This study aimed to investigate the association between mobile phone use in daily life and the risk of dementia incidence in community-dwelling adults based on the data from the UK Biobank.Methods: Participants in the UK Biobank aged 60 years or older with no diagnosis of dementia at the time of recruitment were included in this prospective cohort study. A Cox regression model adjusted for sociodemographic characteristics, general health factors, mental health, lifestyle factors, comorbidities, and medication use was used to estimate the hazard ratio (HR) and confidence interval (CI) of the association between mobile phone use and dementia risk. Results: The final analyses included 213,181 participants. During a median follow-up period of 12.4 years, 6,344 cases of incident dementia occurred. Mobile phone use displayed a modest association with lower risk of dementia incidence, with HRs of 0.85 (95% CI: 0.79-0.91), 0.85 (95% CI: 0.80-0.91), 0.78 (95% C: 0.71-0.86), 0.86 (95% CI: 0.77-0.96), and 0.83 (95% CI: 0.70-0.98) for participants who reported phone call usage of fewer than 5 minutes, 5-29 minutes, 30-59 minutes, 1-3 hours, and more than 3 hours per week, respectively, compared with non-users. In addition, the proportions of the association medicated by family/friend visits and other leisure/social activities were 2.62% (95% CI: -0.64-6.51) and 2.22% (95% CI: 1.12-4.12), respectively.Conclusions: Daily mobile phone use is significantly associated with a reduced risk of incident dementia in community-dwelling adults in the UK Biobank population. This association seems to be mediated by improved social and mental activities.