Objectives: To investigate whether duration of television (TV) viewing in young children is associated with subsequent development of asthma.
Design: Prospective longitudinal cohort study.
Setting: Avon Longitudinal Study of Parents and Children (ALSPAC), United Kingdom.
Participants: Children taking part in Avon Longitudinal Study of Parents and Children (ALSPAC) with no wheeze up to 3 ½ years with follow up data at 11 ½ years.
Main outcome measures: Asthma defined as: Doctor diagnosed asthma by 7 ½ years with symptoms and/or treatment in last 12 months at 11 ½ years. Parental report of hours of children’s television viewing per day was ascertained at 39 months.
Results: In children asymptomatic for wheeze to 3½ years with follow up data at 11½ years, asthma prevalence was 6% (185/3065). Increased TV viewing at 3 ½ years was associated with increased prevalence of asthma at 11 ½ years (p for linear trend=0.0003). Children who watched television for more than 2 hours per day were almost twice as likely to develop asthma by 11 ½ years than those watching <2 hours TV per day (Adjusted Odds Ratio (AOR) (95% Confidence Interval) 1.8 (1.2 to 2.6)).
Conclusion: Longer duration of TV viewing in children asymptomatic for wheeze at 3½ years was associated with the development of asthma in later childhood.