Association of Olfactory Impairment With All-Cause Mortality: A Systematic Review and Meta-analysis.

Importance: Olfactory impairment is highly prevalent and associated with multiple comorbidities, including neurodegenerative, cardiovascular, nutritional, and immune disorders. However, epidemiologic associations between olfactory impairment and mortality are discordant.

Objective: To systematically clarify the epidemiologic associations between olfactory impairment and mortality.