Dataset Information

The predictive value of smoking expectancy and the heritability of its accuracy.

ABSTRACT:

Introduction

Among smokers, former smokers, and never-smokers, this study aimed to (a) determine the predictive value of smoking expectancy on future smoking status, and (b) test the relative contribution of genes and environment to a person's ability to accurately predict future smoking status. For smokers, smoking expectancy reflects the intention to continue smoking; for former smokers, it reflects the intention to take up smoking again; and for never-smokers, it reflects the intention to initiate smoking.

Methods

A longitudinal design was employed in which participants of the Netherlands Twin Register completed 2 consecutive surveys 2 years apart between 1993 and 2011 (3,591 adolescents aged 14-18 years), or between 1993 and 2004 (11,568 adults, aged 18+ years). Smoking expectancy was measured by asking, "Do you think you'll smoke in a year's time?", with answer categories ranging from "certainly not" to "absolutely yes" on a 5-point scale. To determine the predictive value of smoking expectancy, analyses were performed in smokers, former smokers, and never-smokers separately. Data of 2,987 adolescents and 4,911 adult twins were analyzed to estimate heritability. A dichotomous variable reflected the ability to predict future smoking status (correct/incorrect).

Results

Smoking expectancy significantly predicted future smoking status among former smokers and never-smokers. The ability to accurately predict future smoking status was explained by additive genetic factors for 59% of adolescents and 27% of adults, with the remainder being explained by unique environmental factors.

Conclusions

A single question on smoking expectancy helps predict future smoking status. Variation in how well subjects predict their future smoking behavior is influenced by genetic factors, especially during adolescence.

SUBMITTER: Treur JL

PROVIDER: S-EPMC3983427 | biostudies-literature | 2014 Mar

REPOSITORIES: biostudies-literature

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Publications

The predictive value of smoking expectancy and the heritability of its accuracy.

Treur Jorien L JL Boomsma Dorret I DI Lubke Gitta H GH Bartels Meike M Vink Jacqueline M JM

Nicotine & tobacco research : official journal of the Society for Research on Nicotine and Tobacco 20131029 3

<h4>Introduction</h4>Among smokers, former smokers, and never-smokers, this study aimed to (a) determine the predictive value of smoking expectancy on future smoking status, and (b) test the relative contribution of genes and environment to a person's ability to accurately predict future smoking status. For smokers, smoking expectancy reflects the intention to continue smoking; for former smokers, it reflects the intention to take up smoking again; and for never-smokers, it reflects the intentio ...[more]

PMID: 24169813

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Dataset Information

The predictive value of smoking expectancy and the heritability of its accuracy.

Introduction

Methods

Results

Conclusions

Publications

The predictive value of smoking expectancy and the heritability of its accuracy.

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