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Associations of Regular Internet Usage with All-Cause and Cause-Specific Mortality: A Prospective Cohort Study
Cheng-Shen Qiu1, Xu-Lian Tang1, Hong-Min Li1
1Department of Epidemiology, School of Public Health, Southern Medical University, Guangzhou, China.
Objectives:
The impact of internet usage on mortality is not widely known. This study intended to investigate the associations between regular internet usage and the risks of all-cause and cause-specific mortality, while also ascertaining potential factors that may modify these correlations.
Design:
A community-based prospective cohort study.
Setting And Participants:
The study included 21,481 individuals [mean (SD) age, 64.1 (11.0) years] from the Health and Retirement Study, with data collected between 2006 and 2020.
Methods:
The Cox proportional hazards regression model was used to evaluate the associations between regular internet usage and the risks of all-cause and cause-specific mortality, adjusting for demographic factors, lifestyle behaviors, and other potential confounding factors. Moreover, we explored the association between daily hours of internet usage and the risk of outcomes.
Results:
Regular internet usage was significantly associated with a lower risk of all-cause mortality (hazard ratio, 0.78; 95% CI, 0.74-0.83) and cardiovascular mortality (hazard ratio, 0.72; 95% CI, 0.64-0.82). No significant interaction effects were observed for age, sex, regular exercise, or current alcohol consumption (all P interactions > .05). Additionally, estimations for daily hours of usage indicated a U-shaped relationship with all-cause mortality. Adults who used 2.1 to 4 hours per day had the lowest risk; however, not all estimations showed their significance on account of the limited sample size.
Conclusions And Implications:
Regular internet usage was associated with a lower risk of all-cause and cardiovascular mortality, which may prompt consideration of the beneficial impact of internet usage on lifespan.
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