Implementation of key demand-reduction measures of the WHO Framework Convention on Tobacco Control and change in smoking prevalence in 126 countries: an association study
Summary
Background
The WHO Framework Convention on Tobacco Control (WHO FCTC) has mobilized efforts among 180 parties to combat the global tobacco epidemic. This study examined the association between highest-level implementation of key tobacco control demand-reduction measures of the WHO FCTC and smoking prevalence over the treaty’s first decade.
Methods
We used WHO data from 126 countries to examine the association between the number of highest-level implementations of key demand-reduction measures (WHO FCTC articles 6, 8, 11, 13, and 14) between 2007 and 2014 and smoking prevalence estimates between 2005 and 2015. McNemar tests were done to test differences in the proportion of countries that had implemented each of the measures at the highest level between 2007 and 2014. Four linear regression models were computed to examine the association between the predictor variable (the change between 2007 and 2014 in the number of key measures implemented at the highest level), and the outcome variable (the percentage point change in tobacco smoking prevalence between 2005 and 2015).
Findings
Between 2007 and 2014, there was a significant global increase in highest-level implementation of all key demand-reduction measures.
The mean smoking prevalence for all 126 countries was 24·73% (SD 10·32) in 2005 and 22·18% (SD 8·87) in 2015, an average decrease in prevalence of 2·55 percentage points (SD 5·08; relative reduction 10·31%).
Unadjusted linear regression showed that increases in highest-level implementations of key measures between 2007 and 2014 were significantly associated with a decrease in smoking prevalence between 2005 and 2015. Each additional measure implemented at the highest level was associated with an average decrease in smoking prevalence of 1·57 percentage points (95% CI –2·51 to –0·63, p=0·001) and an average relative decrease of 7·09% (–12·55 to –1·63, p=0·011).
Controlling for geographical subregion, income level, and WHO FCTC party status, the per-measure decrease in prevalence was 0·94 percentage points (–1·76 to –0·13, p=0·023) and an average relative decrease of 3·18% (–6·75 to 0·38, p=0·079). This association was consistent across all three control variables.
Interpretation
Implementation of key WHO FCTC demand-reduction measures is significantly associated with lower smoking prevalence, with anticipated future reductions in tobacco-related morbidity and mortality.
These findings validate the call for strong implementation of the WHO FCTC in the WHO’s Global Action Plan for the Prevention and Control of Non-communicable Diseases 2013–2020, and in advancing the UN’s Sustainable Development Goal 3, setting a global target of reducing tobacco use and premature mortality from non-communicable diseases by a third by 2030.
Research in context
Evidence before this study
The researchers searched MEDLINE, PubMed, and Google Scholar for studies published in English or French from database inception to Nov 30, 2016. They also askded tobacco control experts about any articles that might have been submitted or in press. They also searched Google Scholar and Google for grey literature.
Two studies were identified that examined the empirical relationship between the implementation of tobacco control demand measures of the WHO FCTC and smoking prevalence. First, Dubray and colleagues (2015) found that overall, countries with higher MPOWER composite scores in 2008 experienced greater decreases in current tobacco smoking between the years 2006 and 2009. Fewer than 60 countries had sufficient data to meet the inclusion criteria. Second, Anderson and colleagues (2016) found a negative association between higher policy scores (articles 6, 8, 11, 13, and 14 in 2010) and change in smoking prevalence between 2010 and 2015.
Added value of this study
The new study offers a comprehensive global assessment of the effect of the change in progress of highest-level implementation of key tobacco control demand-reduction measures of the WHO FCTC on reductions in smoking prevalence over the treaty’s first decade.
First, the new analyses were done with a cohort of 126 countries for which WHO had computed trend estimates of smoking prevalence for 2005 and 2015.
Second, the outcome variable was the difference in smoking prevalence over a broader 10-year period (2005–15), corresponding to the first decade of the WHO FCTC.
Third, the predictor variable for each of the 126 countries was the change in the number of key demand-reduction measures that had been implemented at the highest level between 2007 (WHO’s first analysis) and 2014 (WHO’s most recent analysis), rather than the single timepoint measures used in Dubray and colleagues’ and Anderson and colleagues’ studies.
The new study’s use of changes in the number of highest-level implementations allows for a more rigorous assessment of whether increases in implementation of tobacco control demand-reduction measures were associated with decreases in prevalence. Additionally, the present study assessed the effect of five key WHO FCTC measures on changes in smoking prevalence over a 10-year period, whereas the other studies examined the association of an aggregate policy score with change in smoking prevalence over a 3-year (Dubray and colleagues) or a 5-year (Anderson and colleagues) period.
Implications of all the available evidence
Although the progress of WHO FCTC ratification has been remarkable (179 countries and the European Union, covering nearly 90% of the world’s population), implementation of the treaty has been slow and has not always been at the highest level.
The present results show that countries that have implemented key demand-reduction measures of the WHO FCTC at the highest level have experienced significant decreases in smoking prevalence, with the magnitude of the decrease being proportional to the number of highest-level implementations. Finally, these results support the call for full implementation of the WHO FCTC in WHO’s Global Action Plan for the Prevention and Control of Non-communicable Diseases 2013–2020 and Sustainable Development Goal 3.
