TitlePassive smoking assessed by salivary cotinine and self-report in relation to cause-specific mortality: 17-year follow-up of study participants in the UK Health and Lifestyle Survey.
Publication TypeJournal Article
Year of Publication2014
AuthorsBatty, GD, Gale, CR, Jefferis, B, Kvaavik, E
JournalJ Epidemiol Community Health
Date Published2014 Dec
KeywordsAdult, Cotinine, Female, Follow-Up Studies, Health Surveys, Humans, Male, Middle Aged, Mortality, Saliva, Self Report, Tobacco Smoke Pollution, United Kingdom

BACKGROUND: Evidence that passive smoking is a risk factor for cardiovascular disease and selected cancers is largely derived from studies in which this exposure is self-reported. Objective assessment using biochemical techniques may yield a more accurate estimate of risk, although each approach has its strengths and weaknesses. We examined the association of salivary cotinine, a widely utilised biomarker for passive smoking, and self-reported passive smoking in the home, with mortality from all causes, cardiovascular disease and all cancers combined.

METHODS: In 1992, investigators on the UK Health and Lifestyle Survey collected data on salivary cotinine, self-reported smoking (direct and passive) and a range of covariates in 3731 men and women aged 25 years and over. Mortality was ascertained using linkage to national death records.

RESULTS: Analyses were based on 2523 individuals (1433 [57%] women) who classified themselves as non-smokers (never and former). Seventeen years of follow-up gave rise to 588 deaths (253 from cardiovascular disease and 146 from cancer). In men, adjusted hazard ratios (HR) for the association between cotinine levels (1.3-15.0 [high] vs ≤0.3 [low] ng/mL) and the various mortality outcomes were weak for total mortality (HR; 95% CI: 1.22; 0.91 to 1.64) and cardiovascular disease (1.25; 0.78 to 1.99) and absent for all cancers combined (1.10; 0.61 to 2.00). Corresponding associations were generally stronger when self-reported passive smoking (some vs none) was the exposure of interest: 1.53 (1.12 to 2.08), 1.88 (1.20 to 2.96) and 1.58 (0.85 to 2.93). The pattern of association for women in both sets of analyses was less consistent.

CONCLUSIONS: In men in the present study, compared with our biochemical marker of passive smoking, cotinine, mortality was generally more consistently associated with self-reported passive smoking.

Alternate JournalJ Epidemiol Community Health
PubMed ID25138392
Grant ListMC_UP_A620_1015 / / Medical Research Council / United Kingdom
MC_UU_12011/2 / / Medical Research Council / United Kingdom
MR/K026992/1 / / Medical Research Council / United Kingdom