Temporal trends in the mortality rate of Alzheimer's disease and other dementias attributable to smoking, 1990-2017.

BACKGROUND

Smoking is a well-defined modifiable risk factor for dementia. Understanding national temporal trends of dementia deaths due to smoking is critical for prioritizing action for the global prevention of dementia, as well as smoking prevention. We aimed to estimate the patterns and temporal trends of smoking-attributable dementia-related deaths for 195 countries from 1990 to 2017.

METHODS

Detailed data on dementia deaths attributable to smoking were obtained from the Global Burden of Disease Study 2017. The estimated annual percentage change (EAPC) was used to quantify the temporal trends in the age-standardized mortality rate (ASMR) of dementia attributable to smoking by age, sex, region, and country.

RESULTS

In 2017, approximately 2.51 million deaths attributable to dementia occurred globally; among them, 317,747 dementia-related deaths were attributable to smoking. The corresponding ASMR decreased by 31.1% from 6.33 per 100,000 population in 1990 to 4.36 per 100,000 population in 2017, with an EAPC of -1.43 (95% CI -1.48, -1.37). The reduction in the ASMR in women (EAPC = -2.13; 95% CI -2.18, -2.08) was more pronounced than that in men (EAPC = -1.26; 95% CI -1.32, -1.20). Most geographic region have achieved significant declines in ASMRs since 1990; however, Central Asia and 24 countries and territories showed increased trends in ASMRs over the same period.

CONCLUSIONS

Despite large reductions in the ASMRs of dementia attributable to smoking over the past three decades, the corresponding number of deaths has steadily increased due to population growth and aging. The ASMR trend patterns were heterogeneous across countries, and there were undesirable increases in the dementia ASMR in some countries. Strengthened efforts for tobacco prevention are still needed to reduce the disease burden due to smoking, particularly in countries where the dementia ASMR is increasing.