A randomised controlled trial of a complex intervention to reduce children's exposure to secondhand smoke in the home

Tob Control. 2018 Mar;27(2):155-162. doi: 10.1136/tobaccocontrol-2016-053279. Epub 2017 Apr 21.

Abstract

Objectives: Exposing children to secondhand tobacco smoke (SHS) causes significant harm and occurs predominantly through smoking by caregivers in the family home. We report a trial of a complex intervention designed to reduce secondhand smoke exposure of children whose primary caregiver feels unable or unwilling to quit smoking.

Design: An open-label, parallel, randomised controlled trial.

Setting: Deprived communities in Nottingham City and County, England PARTICIPANTS: Caregivers resident in Nottingham City and County in England who were at least 18 years old, the main caregiver of a child aged under 5 years living in their household, and reported that they were smoking tobacco inside their home.

Interventions: We compared a complex intervention combining personalised feedback on home air quality, behavioural support and nicotine replacement therapy for temporary abstinence with usual care.

Main outcomes: The primary outcome was change in air quality in the home, measured as average 16-24 hours levels of particulate matter of < 2.5 µm diameter (PM2.5), between baseline and 12 weeks. Secondary outcomes included changes in maximum PM2.5, proportion of time PM2.5 exceeded WHO recommended levels of maximum exposure of 25 µg/mg3, child salivary cotinine, caregivers' cigarette consumption, nicotine dependence, determination to stop smoking, quit attempts and quitting altogether during the intervention.

Results: Arithmetic mean PM2.5 decreased significantly more (by 35.2 %; 95% CI 12.7% to 51.9 %) in intervention than in usual care households, as did the proportion of time PM2.5 exceeded 25 µg/mg3, child salivary cotinine concentrations, caregivers' cigarette consumption in the home, nicotine dependence, determination to quit and likelihood of having made a quit attempt.

Conclusions: By reducing exposure to SHS in the homes of children who live with smokers unable or unwilling to quit, this intervention offers huge potential to reduce children's' tobacco-related harm.

Trial registration number: ISRCTN81701383.This trial was funded by the UK National Institute for Health Research (NIHR): RP-PG-0608-10020.

Keywords: Addiction; Secondhand smoke; Smoking Caused Disease.

Publication types

  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Air Pollution / analysis
  • Air Pollution, Indoor / analysis
  • Air Pollution, Indoor / prevention & control*
  • Child, Preschool
  • Cotinine / metabolism
  • Humans
  • Particulate Matter / analysis
  • Saliva / metabolism
  • Smoking / drug therapy*
  • Tobacco Smoke Pollution / analysis
  • Tobacco Smoke Pollution / prevention & control*
  • Tobacco Use Cessation Devices
  • Treatment Outcome
  • Young Adult

Substances

  • Particulate Matter
  • Tobacco Smoke Pollution
  • Cotinine

Associated data

  • ISRCTN/ISRCTN81701383