Smoking Seems Not to Be Linked to Increased Dementia Risk
No increased risk for dementia observed when adjusting for risk of death without dementia
TUESDAY, March 26, 2019 (HealthDay News) -- After adjusting for the competing risk of death without dementia, smoking is not associated with an increased risk for dementia, according to a study published online March 26 in the Journal of Alzheimer's Disease.
Erin L. Abner, Ph.D., from the University of Kentucky in Lexington, and colleagues examined tobacco smoking as a risk for dementia and neuropathologic burden in 531 initially cognitively normal older adults, followed for an average of 11.5 years.
The researchers found that 20.9 percent of the participants were diagnosed with dementia and 45.6 percent died without dementia. The hazard ratio for dementia was 1.64 (95 percent confidence interval [CI], 1.09 to 2.46) for former smokers versus never smokers and 1.20 (95 percent CI, 0.50 to 2.87) for current smokers versus never smokers. The subdistribution hazard ratio (sHR) was 1.21 (95 percent CI, 0.81 to 1.80) for former smokers and 0.70 (95 percent CI, 0.30 to 1.64) for current smokers in the Fine-Gray model, which accounts for the competing risk of death without dementia. Current smoking was associated with an increased incidence of death without dementia (sHR, 2.38; 95 percent CI, 1.52 to 3.72).
"This may have implications for the current focus on smoking cessation as a modifiable risk for dementia," the authors write. "We emphasize that this is not to say that efforts invested in smoking cessation are misguided or unimportant."