Cigarette smoking and cognitive health in elderly Japanese

OBJECTIVE: To examine the relationships between smoking status and various domains of cognitive function in community-dwelling elderly subjects. METHODS: Participants (N = 4348) were asked about smoking status, demographic variables, and lifestyle factors, and underwent multidimensional neurocognitive tests. RESULTS: All analyses were conducted separately by sex. Women never smokers exhibited significantly better scores than past and/or current smokers in some neurocognitive tests. Among men, never smokers had significantly higher scores, such as in the Symbol Digit Substitution Test. Multiple linear regression analysis showed that pack-years (history of smoking) were significantly associated with the Symbol Digit Substitution Test in men. CONCLUSIONS: Smoking status may be associated with a decline in processing speed, and this decline varies by sex.