Impact of secondhand smoke exposure on cognitive function among middle-aged and older women in China: findings from three waves of the China Health and Retirement Longitudinal Study

Abstract

ObjectivesTo examine the association between secondhand smoke (SSH) and women’s global cognitive function and cognitive subdomains.DesignCohort study.ParticipantsData for this study were obtained from the China Health and Retirement Longitudinal Study (2011-2013-2015), and pooled analysis was applied to wave 1 and wave 2 (2011–2013), wave 2 and wave 3 (2013–2015) and wave 1 and wave 3 (2011–2015). Data from a total of 6875 Chinese women with normal cognitive function at baseline were selected for analysis, including 2981 who were interviewed in 2011, 2471 in 2013, and 1894 in 2015.Main outcome measures and methodsSHS was classified based on the number of exposed years (<25 years, ≥25 years to <30 years, ≥30 years to <40 years, ≥40 years). Global cognitive function, visuospatial ability, orientation and attention, and episodic memory function were used as measures of cognitive function. Three waves of data were pooled using a dummy variable to differentiate between 2-year and 4-year groups. LDV models were used to examine independent associations between SHS and cognitive function. Demographic factors, socioeconomic factors, baseline cognitive functioning and health conditions were controlled for in our models.ResultsSSH was found to be inversely and significantly associated with cognitive function. Compared with those who had not been exposed to household SSH, women who had lived with a smoking husband had a significantly faster cognition decline, especially in global cognitive function (β=−0.33, 95% CI=−0.66 to −0.01, p<0.01), visuospatial ability (β=−0.04, 95% CI=−0.08 to −0.01, p<0.05) and episodic memory function (β=−0.16, 95% CI=−0.31 to −0.01, p=0.031).ConclusionsHousehold SSH exposure for more than 40 years was associated with a more significant decline in global cognitive function, visuospatial ability and episodic memory function, but not in orientation and attention function among older Chinese women.

Higher Blood Cotinine Level is Associated with Worse Cognitive Functioning in Non-smoking Older Adults

“…Controversy exists on the association between SHS and cognitive functioning in older adults, although a limited number of studies have examined the relationship between the two and found a negative cognitive effect of SHS. In a longitudinal study of 6875 middle-aged and older Chinese women, women who had lived with a smoking husband experienced a signi cantly faster decline in global cognitive function, visuospatial ability, and episodic memory function than those who had not (Bai et al, 2020). However, in that study, researchers failed to adjust important covariates such as body mass index, exercise, and alcohol use.…”

“…A limited number of studies have examined the effect of SHS on cognitive functioning in this population (Llewellyn et al, 2009). Among the existing studies, many used participants' self-report exposure to SHS (Bai, Jin, & Huang, 2020;Barnes et al, 2010;Friedrich, 2007;Heffernan & O'Neill, 2013) and thus was unprecise and subject to recall and report bias. Thus, studies involving the use of biomarkers to objectively measure the extent of SHS are needed to clarify its relationship with cognitive functioning in this growing population.…”

Risk Factors, Lifestyle Behaviors, and Vascular Brain Health

“…65 Even secondhand smoke, particularly over a long duration, has been associated with worse cognitive function. 66…”

Secondhand smoke exposure from the indoor and outdoor shisha centers located at the perimeter of educational institutions in Malaysia: a cross-sectional study

“…In children, SHS can lead to the development of ear infections, asthma, and respiratory infections including fatal sudden infant death syndrome; in adults, it is linked to an increased risk of cardiovascular diseases and lung cancers [2]. Household SHS exposure was associated with a significant decline in global cognitive function, visuospatial ability, and memory function among Chinese women [14].…”