Article Text
Abstract
Introduction The hardening hypothesis proposes that the proportion of hardcore smokers increases when smoking prevalence declines. To evaluate whether such hardening occurs in South Korea, we examined the association between quitting behaviours, the number of cigarettes smoked per day and the proportion of hardcore smokers and smoking prevalence among local districts in South Korea.
Methods This study used the cross-sectional data from the Korea Community Health Survey (2010–2018) to examine local district-level associations between smoking prevalence and quit attempts, quit plans, quit ratios, cigarettes smoked per day and the proportion of hardcore smokers. Panel regression analysis was performed using the indicators of hardcore smoking (quit attempts, quit plans, quit ratios, cigarettes smoked per day and proportion of hardcore smokers) as the outcome variables, and prevalence of smoking, local districts, age and sex as predictor variables.
Results When the smoking prevalence of the districts decreased by 1%, quit attempts, quit plans and quit ratios increased by 0.24% (95% CI 0.11 to 0.37), 0.37% (95% CI 0.26 to 0.47) and 1.71% (95% CI 1.65 to 1.76), respectively. Cigarette consumption decreased by 0.17 cigarettes per day (95% 0.15 to 0.19), and the prevalence of hardcore smokers decreased by 0.88% (95% CI 0.78 to 0.98) when smoking prevalence decreased by 1%.
Conclusion Hardening of smoking did not occur in South Korea when smoking prevalence declined, which suggests tobacco control policies in South Korea have been effective in reducing smoking prevalence without increasing the proportion of hardcore smokers.
- cessation
- public policy
- addiction
Data availability statement
Data are available in a public, open access repository. Korea Community Health Survey is an anonymised data disclosed to the public. Data request and analytic guidelines can be downloaded from the KCHS website (http://KCHS.cdc.go.kr/) in Korean.
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Data availability statement
Data are available in a public, open access repository. Korea Community Health Survey is an anonymised data disclosed to the public. Data request and analytic guidelines can be downloaded from the KCHS website (http://KCHS.cdc.go.kr/) in Korean.
Footnotes
BJ and JAL contributed equally.
Correction notice This article has been corrected since it first published. Equal contributor statement is added in the gutter section.
Contributors Concept and design: BJ, JAL and H-JC. Acquisition, analysis or interpretation of data: all authors. Drafting of the manuscript: BJ, JAL and H-JC. Critical revision of the manuscript for important intellectual content: all authors. Statistical analysis: JAL and Y-JK. Supervision and guarantor: H-JC.
Funding The authors have not declared a specific grant for this research from any funding agency in the public, commercial or not-for-profit sectors.
Competing interests No, there are no competing interests.
Provenance and peer review Not commissioned; externally peer reviewed.
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