Smoking and cognitive change from age 11 to age 80

Do Financial Literacy and Financial Education Influence Smoking Behavior in the United States?

Smoking is still a serious economic, health, and social problem despite various efforts to curb its prevalence. We examined the influence of financial literacy and financial education on the smoking behavior in the United States in terms of the use of rational decision-making abilities to reduce irrational behavior. We hypothesized that financial literacy and financial education, as proxies for rational decision making, would reduce the likelihood of smoking. We used data from the Preference Parameters Study (PPS) of Osaka University conducted in the United States in 2010 and applied probit regression models to test our hypothesis on a sample of 3831 individuals. We found that financially literate people are less likely to be smokers, though we found no clear role of financial education in reducing the likelihood of smoking. Further, respondents' gender, age, unemployment status, and risky health behaviors such as drinking and gambling, have a significantly positive association with smoking, while marital status, university degree, family size, household income, household assets, physical exercise, and level of happiness have a significantly negative association. Our findings suggest that financial literacy, as an instrument encouraging rational decision making, could be a tool to help reduce smoking in the United States.

Cognitive decline trajectories and influencing factors in China: A non-normal growth mixture model analysis

BACKGROUND

With the increase in the aging population worldwide, cognitive decline has become an important research topic. The purpose of this study is to examine the cognitive development trajectories and influencing factors of different latent classes of Chinese elderly people. This will provide us with effective guidance for prevention and intervention.

METHODS

Four waves of data from the Chinese Longitudinal Healthy Longevity Survey (CLHLS) were collected and included 2440 Chinese elderly individuals. The cognitive function of elderly individuals was measured using the Mini Mental State Examination (MMSE). A nonnormal Growth Mixture model (GMM) with five time-invariant covariates was used to identify the different trajectories of cognitive decline in elderly individuals.

RESULTS

Three latent decline trajectory groups were identified: stable cognitive group (SCG), high initial level - cognitive decline group (HIL-CDG), and high initial level - cognitive decline group (LIL-CDG). Elderly women were more likely to be assigned to a lower level subgroup than men. People who smoked and played cards or mahjong were more likely to be assigned to a cognitively stable group.

CONCLUSION

Education may help raise the upper limit of cognition. Smoking may impair cognitive upper limit. A small amount of alcohol intake and participation in cognitive and physical activities may help the elderly to delay cognitive decline in their later years.

Combined Effect of Noise and Smoking on the Cognitive Performance of Automotive Industry Workers

Introduction:

Noise is an environmental stressor and can cause or exacerbate mental disorders, and affect the individual performance in certain conditions. This study aimed to evaluate the combined effects of noise and smoking on the cognitive performance of the workers in the automotive industry.

Methods:

This research is a descriptive-analytical study with a cross-sectional design conducted on 300 workers randomly assigned into two groups of noise-exposed and nonexposed. They were examined using computerized tests, including the Tower of London test (TOL), Continuous Performance test (CPT), and Stroop test. The sound pressure levels were measured based on an 8-hour equal-loudness contour in each group according to ISO 9612 standard, using the Testo CEL-815 sound level meter.

Results:

The study of combined effects of noise and smoking on 12 CPT indicators using the 2-way Analysis of Variance (ANOVA) indicate that noise and smoking factors had a significant impact on the mean number of errors and correct responses in the third 50-stimuli stage, the mean number of errors and correct responses in the second 50-stimuli stage with P<0.001, P<0.001, P=0.012 and P<0.001 for smoking respectively, but only noise affected the other 7 indicators (P<0.001).

Conclusion:

Smoking and noise have negative impacts on concentration, attention, and cognitive processing speed, which can lead to an individual’s mistakes and delayed decision making at the workplace.

Health literacy, cognitive ability and smoking: a cross-sectional analysis of the English Longitudinal Study of Ageing

OBJECTIVES

We used logistic regression to investigate whether health literacy and cognitive ability independently predicted whether participants have ever smoked and, in ever smokers, whether participants still smoked nowadays.

DESIGN

Cross-sectional study.

SETTING

This study used data from Wave 2 (2004-05) of the English Longitudinal Study of Ageing, which is a cohort study of adults who live in England and who, at baseline, were aged 50 years and older.

PARTICIPANTS

8734 (mean age=65.31 years, SD=10.18) English Longitudinal Study of Ageing participants who answered questions about their current and past smoking status, and completed cognitive ability and health literacy tests at Wave 2.

PRIMARY AND SECONDARY OUTCOME MEASURES

The primary outcome measures were whether participants reported ever smoking at Wave 2 and whether ever smokers reported still smoking at Wave 2.

RESULTS

In models adjusting for age, sex, age left full-time education and occupational social class, limited health literacy (OR=1.096, 95% CI 0.988 to 1.216) and higher general cognitive ability (OR=1.000, 95% CI 0.945 to 1.057) were not associated with reporting ever smoking. In ever smokers, limited compared with adequate health literacy was associated with greater odds of being a current smoker (OR=1.194, 95% CI 1.034 to 1.378) and a 1 SD higher general cognitive ability score was associated with reduced odds of being a current smoker (OR=0.878, 95% CI 0.810 to 0.951), when adjusting for age, sex, age left full-time education and occupational social class.

CONCLUSIONS

When adjusting for education and occupation variables, this study found that health literacy and cognitive ability were independently associated with whether ever smokers continued to smoke nowadays, but not with whether participants had ever smoked.

Does incipient dementia explain normal cognitive decline determinants? Lothian birth cohort 1921

The presence of an apolipoprotein E (APOE) ε4 allele, lower physical fitness, smoking, and lower serum vitamin B-12 have been reported as contributing to poorer cognitive function in LBC1921 at age 79, after adjusting for childhood intelligence. Because incident dementia was not previously ascertained within LBC1921, it is possible that preclinical or unrecognized cases at age 79 influenced findings. Dementia cases arising over approximately 16 years of follow-up were determined by a consensus using evidence from electronic medical records, death certificates, and clinical reviews. The analyses from the original reports were repeated after the exclusion of those who had developed dementia. In a subsequent set of analyses, the authors considered the potential impact of terminal decline, excluding those participants who died within 4 years of baseline testing. Positive APOE ε4 status was found to be associated with poorer Logical Memory (Wechsler, 1987) at age 79 (F(1, 355) = 8.16, p = .005, ηp2 = 0.022; n = 359) and lower Moray House Test (Scottish Council for Research in Education, 1933) score at age 79 (F(1, 357) = 4.27, p = .04, ηp2 = 0.012; n = 363). Lower age 79 IQ was associated with smoking (F(2, 360) = 3.67, p = .026, ηp2 = 0.020; n = 367), lower vitamin B-12 (Sβ = 0.11, p = .014; n = 367), and poorer physical fitness (Sβ = 0.21, p < .001; n = 359). Only the relationship with physical fitness remained significant after excluding those who died within 4 years of baseline (Sβ = 0.203, p < .001; n = 310). Unrecognized dementia had little or no effect on determinants of lifetime cognitive ageing in LBC1921. Terminal decline may have accounted for the associations with age 11 to age 79 cognitive change. (PsycINFO Database Record

Healthy cognitive ageing in the Lothian Birth Cohort studies: marginal gains not magic bullet

In the face of shifting demographics and an increase in human longevity, it is important to examine carefully what is known about cognitive ageing, and to identify and promote possibly malleable lifestyle and health-related factors that might mitigate age-associated cognitive decline. The Lothian Birth Cohorts of 1921 (LBC1921, n = 550) and 1936 (LBC1936, n = 1091) are longitudinal studies of cognitive and brain ageing based in Scotland. Childhood IQ data are available for these participants, who were recruited in later life and then followed up regularly. This overview summarises some of the main LBC findings to date, illustrating the possible genetic and environmental contributions to cognitive function (level and change) and brain imaging biomarkers in later life. Key associations include genetic variation, health and fitness, psychosocial and lifestyle factors, and aspects of the brain's structure. It addresses some key methodological issues such as confounding by early-life intelligence and social factors and emphasises areas requiring further investigation. Overall, the findings that have emerged from the LBC studies highlight that there are multiple correlates of cognitive ability level in later life, many of which have small effects, that there are as yet few reliable predictors of cognitive change, and that not all of the correlates have independent additive associations. The concept of marginal gains, whereby there might be a cumulative effect of small incremental improvements across a wide range of lifestyle and health-related factors, may offer a useful way to think about and promote a multivariate recipe for healthy cognitive and brain ageing.

The Differential Effects of Alcohol and Nicotine-Specific Nitrosamine Ketone on White Matter Ultrastructure

Aims

The chronic consumption of alcohol is known to result in neurodegeneration and impairment of cognitive function. Pathological and neuroimaging studies have confirmed that brain atrophy in alcoholics is mainly due to widespread white matter (WM) loss with neuronal loss restricted to specific regions, such as the prefrontal cortex. Neuroimaging studies of cigarette smokers also suggest that chronic inhalation of tobacco smoke leads to brain atrophy, although the neurotoxic component is unknown. As a high proportion of chronic alcoholics also smoke cigarettes it has been hypothesized that at least some alcohol-related brain damage is due to tobacco smoke exposure.

Methods

39 Long Evans rats were subjected to 8 weeks exposure to alcohol and/or 5 weeks co-exposure to nicotine-specific nitrosamine ketone (NNK), a proxy for tobacco smoke. Their frontal WM was then assayed with transmission electron microscopy.

Results

NNK and ethanol co-exposure had a synergistic effect in decreasing myelinated fibre density. Furthermore, NNK treatment led to a greater reduction in myelin sheath thickness than ethanol whereas only the ethanol-treated animals showed a decrease in unmyelinated fibre density.

Conclusion

These data suggest that NNK causes WM degeneration, an effect that is exacerbated by alcohol, but unlike alcohol, it has little impact on the neuronal components of the brain.

The effects of chronic smoking on the pathology of alcohol-related brain damage

Both pathological and neuroimaging studies demonstrate that chronic alcohol abuse causes brain atrophy with widespread white matter loss limited gray matter loss. Recent neuroimaging studies suggest that tobacco smoking also causes brain atrophy in both alcoholics and neurologically normal individuals; however, this has not been confirmed pathologically. In this study, the effects of smoking and the potential additive effects of concomitant alcohol and tobacco consumption were investigated in autopsied human brains. A total of 44 cases and controls were divided into four groups: 16 non-smoking controls, nine smoking controls, eight non-smoking alcoholics, and 11 smoking alcoholics. The volumes of 26 gray and white matter regions were measured using an established point-counting technique. The results showed trends for widespread white matter loss in alcoholics (p < 0.007) but no effect on gray matter regions. In contrast, smoking alone had no effect on brain atrophy and the combination of smoking and alcohol showed no additional effect. Neuronal density was analyzed as a more sensitive assay of gray matter integrity. Similar to the volumetric analysis, there was a reduction in neurons (29%) in the prefrontal cortex of alcoholics, albeit this was only a trend when adjusted for potential confounders (p < 0.06). There were no smoking or combinatorial effects on neuronal density in any of the three regions examined. These results do not support the hypothesis that smoking exacerbates alcohol-related brain damage. The trends here support previous studies that alcohol-related brain damage is characterized by focal neuronal loss and generalized white matter atrophy. These disparate effects suggest that two different pathogenic mechanisms may be operating in the alcoholic brain. Future studies using ultrastructural or molecular techniques will be required to determine if smoking has more subtle effects on the brain and how chronic alcohol consumption leads to widespread white matter loss.

Adolescent brain maturation and smoking: what we know and where we're headed

Smoking is a leading cause of mortality and morbidity worldwide. Smoking initiation often occurs during adolescence. This paper reviews and synthesizes adolescent development and nicotine dependence literatures to provide an account of adolescent smoking from onset to compulsive use. We extend neurobiological models of adolescent risk-taking, that focus on the interplay between incentive processing and cognitive control brain systems, through incorporating psychosocial and contextual factors specific to smoking, to suggest that adolescents are more vulnerable than adults to cigarette use generally, but that individual differences exist placing some adolescents at increased risk for smoking. Upon smoking, adolescents are more likely to continue smoking due to the increased positive effects induced by nicotine during this period. Continued use during adolescence, may be best understood as reflecting drug-related changes to neural systems underlying incentive processing and cognitive control, resulting in decision-making that is biased towards continued smoking. Persistent changes following nicotine exposure that may underlie continued dependence are described. We highlight ways that interventions may benefit from a consideration of cognitive-neuroscience findings.

Cigarette smoking and p300 amplitude in adults: a systematic review

OBJECTIVE

To determine the association between chronic tobacco cigarette smoking and P300 amplitude.

DESIGN

Systematic review with meta-analysis and meta-regression.

DATA SOURCES

Medline, Cochrane Database of Systematic Reviews, PsychInfo, and Web of Science.

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

Eligible studies contained P300 amplitudes obtained from either visual or auditory stimuli and standard deviations or errors in female and male subjects older than 18 years in a group of nonabstaining chronic cigarette smokers and a nonsmoking control group.

RESULTS

The 9 eligible studies comprised 13 relevant datasets containing 1,956 current cigarette smokers and 2,194 nonsmoking controls (N = 4,150). The P300 amplitude was smaller in cigarette smokers than in nonsmoking controls (Hedges' g effect size = .365; 95% confidence interval [CI] = 0.196-0.534, p < .001). Meta-regression showed significant positive associations between the number of cigarettes smoked per day at the time of the study (slope estimate = .036, 95% CI = 0.016-0.056, p ≤ .001, length of smoking in years (slope estimate = .056, 95% CI = 0.005-0.102, p = .018), pack years (slope estimate = .018, 95% CI = 0.009-0.031 p = .009), and age (slope estimate = .068, 95% CI = 0.025-0.113, p = .002).

CONCLUSIONS

P300 amplitude was smaller in cigarette smokers than in nonsmoking controls, and a possible dose-response relationship was apparent. Findings indicate a possible association between cigarette smoking and decreased P300 amplitude.

Association between tobacco smoking and cognitive functioning in young adults

BACKGROUND

Tobacco smoking represents a considerable public health burden globally. Smoking in older adults is associated with cognitive impairment and more rapid age-associated cognitive decline, but there is a paucity of studies in younger people.

METHOD

Adults aged 18-29 years were recruited from a longitudinal study investigating impulsivity in young people. Exclusion criteria were presence of any axis-I morbidity or cannabis use. Subjects undertook neurocognitive assessment using the Cambridge Neuropsychological Test Automated Battery (CANTAB). Demographic, clinical, and cognitive differences between smokers (N = 37) and nonsmokers (N = 177) were characterized.

RESULTS

Groups were well matched in terms of age, education, income, and gender. In comparison to nonsmokers, nicotine users showed significant cognitive impairments on sustained attention (target detection: p= .005), spatial working memory (errors: p= .023, strategy use: p= .004), executive planning (p= .002), and did not appropriately adjust behavior as a function of risk (Gamble task risk adjustment: p= .004). Smokers were intact on general response speeds and response inhibition.

CONCLUSIONS

These data, using objective translational paradigms, support an association between tobacco smoking and cognitive problems in young people, with implications for such individuals and for society. Future studies should extend these results longitudinally to explore causality, and evaluate effects of nicotinic agents (including anti-smoking medications) on cognition.

Free and nanoencapsulated curcumin prevents cigarette smoke-induced cognitive impairment and redox imbalance

Cigarette smoke-exposure promotes neurobiological changes associated with neurocognitive abnormalities. Curcumin, a natural polyphenol, have shown to be able to prevent cigarette smoke-induced cognitive impairment. Here, we investigated possible mechanisms involved in curcumin protection against cigarette smoke-induced cognitive impairment and, due to its poor bioavailability, we investigated the potential of using curcumin-loaded lipid-core nanocapsules (C-LNC) suspension. Rats were treated with curcumin and cigarette smoke, once a day, 5 days each week, for 30 days. Animals were divided into ten groups: I, control (vehicle/corn oil); II, curcumin 12.5mg/kg; III, curcumin 25mg/kg; IV, curcumin 50mg/kg; V, C-LNC 4 mg/kg; VI, tobacco exposed; VII, curcumin 12.5mg/kg along with tobacco exposure; VIII, curcumin 25mg/kg along with tobacco exposure; IX, curcumin 50mg/kg along with tobacco exposure; X, C-LNC 4 mg/kg along with tobacco exposure. Cigarette smoke-exposure impaired object recognition memory (P<0.001), indicated by the low recognition index, increased biomarkers of oxidative/nitrosative stress such as TBARS (P<0.05) and NOx (P<0.01), decreased antioxidant defenses such as NPSH content (P<0.01) and SOD activity (P<0.01) and inhibited the activities of enzymes involved in ion homeostasis such as Na(+),K(+)-ATPase and Ca(2+)-ATPase. Both curcumin formulations (free and nanoencapsulated) prevented the memory impairment, the redox imbalance and the alterations observed in the ATPases activities. Maintenance of ion homeostasis and redox balance is involved in the protective mechanism of curcumin against tobacco-induced cognitive impairment. Our results suggest that curcumin is a potential therapeutic agent for neurocognition and that C-LNC may be an alternative to its poor bioavailability.

Smoking, childhood IQ, and cognitive function in old age

OBJECTIVES

To examine the association between smoking history and cognitive function in old age, and whether it remains after controlling for childhood cognitive ability (IQ) and adult socioeconomic status (SES).

METHODS

In the Lothian Birth Cohort 1936 Study, 1080 men and women, who previously participated in a nationwide IQ-type test in childhood, were followed up at age 70. The associations between smoking history and age 70 IQ, general cognitive ability (g), processing speed, memory, and verbal ability were assessed.

RESULTS

Lower childhood IQ was associated with a higher risk of becoming a smoker and continuing to smoke in late life, and with reduced lung function (FEV1) in late life. Current smokers scored significantly lower than ex-smokers and never smokers on tests of age 70 IQ, general cognitive ability, and processing speed, but not memory or verbal ability. After controlling for childhood IQ and SES, current smoking at age 70 (but not pack years of smoking) was associated with impairments in general cognitive ability and processing speed.

CONCLUSION

Smoking in old age makes a small, independent contribution to cognitive performance in old age.

A comprehensive assessment of neurocognition in middle-aged chronic cigarette smokers

BACKGROUND

The majority of studies investigating the neurocognitive consequences of chronic smoking have been conducted with adults 60 years and older. Therefore, the scope of neurocognitive dysfunction associated with chronic cigarette smoking in middle age (i.e., 30-60 age range) has not been fully delineated.

METHODS

Twenty-seven (44±9 years of age; 4 females) non-smoking and 30 smoking (49±8 years of age; 4 females) participants completed a comprehensive neurocognitive battery and measures of fine motor dexterity and postural stability. All participants were free of biomedical or psychiatric conditions that may have influenced neurocognitive and motor function.

RESULTS

Smokers performed significantly worse than non-smokers on the following domains: auditory-verbal and visuospatial learning, visuospatial memory, cognitive efficiency, executive skills, general intelligence, processing speed, fine motor dexterity and postural stability. The differences between smokers and non-smokers evidenced moderate to strong effect sizes and were not mediated by age, education, vocational level, estimated verbal intelligence or alcohol consumption. In smokers, a greater number of lifetime years of smoking was related to poorer performance on measures of cognitive efficiency, processing speed and visuospatial skills.

CONCLUSIONS

Results from this middle-aged cohort replicated previous research and provides novel findings indicating that chronic smoking was associated with inferior performance on measures of general intelligence, visuospatial learning and memory and fine motor dexterity. Research that relates measures of neurobiological function/integrity to neurocognition is needed to better understand the mechanisms contributing to the poorer performance across multiple domains demonstrated by smokers.

Cohort profile: the Lothian Birth Cohorts of 1921 and 1936

This cohort profile describes the origins, tracing, recruitment, testing and follow-up of the University of Edinburgh-based Lothian Birth Cohorts of 1921 (LBC1921; N = 550) and 1936 (LBC1936; N = 1091). The participants undertook a general intelligence test at age 11 years and were recruited for these cohorts at mean ages of 79 (LBC1921) and 70 (LBC1936). The LBC1921 have been examined at mean ages of 79, 83, 87 and 90 years. The LBC1936 have been examined at mean ages of 70 and 73 years, and are being seen at 76 years. Both samples have an emphasis on the ageing of cognitive functions as outcomes. As they have childhood intelligence test scores, the cohorts' data have been used to search for determinants of lifetime cognitive changes, and also cognitive change within old age. The cohorts' outcomes also include a range of physical and psycho-social aspects of well-being in old age. Both cohorts have a wide range of variables: genome-wide genotyping, demographics, psycho-social and lifestyle factors, cognitive functions, medical history and examination, and biomarkers (from blood and urine). The LBC1936 participants also have a detailed structural magnetic resonance imaging (MRI) brain scan. A range of scientific findings is described, to illustrate the possible uses of the cohorts.

Chronic cigarette smoking: implications for neurocognition and brain neurobiology

Compared to the substantial volume of research on the general health consequences associated with chronic smoking, little research has been specifically devoted to the investigation of its effects on human neurobiology and neurocognition. This review summarizes the peer-reviewed literature on the neurocognitive and neurobiological implications of chronic cigarette smoking in cohorts that were not seeking treatment for substance use or psychiatric disorders. Studies that specifically assessed the neurocognitive or neurobiological (with emphasis on computed tomography and magnetic resonance-based neuroimaging studies) consequences of chronic smoking are highlighted. Chronic cigarette smoking appears to be associated with deficiencies in executive functions, cognitive flexibility, general intellectual abilities, learning and/or memory processing speed, and working memory. Chronic smoking is related to global brain atrophy and to structural and biochemical abnormalities in anterior frontal regions, subcortical nuclei and commissural white matter. Chronic smoking may also be associated with an increased risk for various forms of neurodegenerative diseases. The existing literature is limited by inconsistent accounting for potentially confounding biomedical and psychiatric conditions, focus on cross-sectional studies with middle aged and older adults and the absence of studies concurrently assessing neurocognitive, neurobiological and genetic factors in the same cohort. Consequently, the mechanisms promoting the neurocognitive and neurobiological abnormalities reported in chronic smokers are unclear. Longitudinal studies are needed to determine if the smoking-related neurobiological and neurocognitive abnormalities increase over time and/or show recovery with sustained smoking cessation.

Social involvement, behavioural risks and cognitive functioning among older people

This study analyses the relationships between cognitive performance, social participation and behavioural risks, taking into account age and educational attainment. We examine individual data for 11 European countries and Israel from the first wave of the Survey on Health, Ageing and Retirement in Europe (SHARE). The stochastic frontier approach methodology enables us to identify different sources of plasticity on cognitive functioning while taking into account age-related decline in cognitive performance. Several social participation variables were examined: employment status, attending educational courses, doing voluntary or charity work, providing help to family, friends or neighbours, participating in sports, social or other clubs, in a religious organisation and in a political or community organisation, and we controlled for age, education, income, physical activity, body-mass index, smoking and drinking. In the pooled sample, the results clearly show that all kinds of social involvement enhance cognitive functions, in particular in work. Moreover, behavioural risks such as physical inactivity, obesity, smoking or drinking were clearly detrimental to cognitive performance. Models for men and women were run separately. For both genders, all social involvement indicators associated with better cognitive performance. The results varied by countries, however, particularly the signs of the associations with a number of indicators of social involvement and behavioural risks.

Smoking increases risk for cognitive decline among community-dwelling older Mexican Americans

OBJECTIVES

Few studies have investigated smoking and cognitive decline (CD) among older Mexican Americans. In this study, the authors explore the relationship between smoking status and cognitive changes over time in a large sample of community-dwelling older adults of Mexican descent.

DESIGN

Latent growth curve analyses were used to examine the decreasing growth in the number of correct responses on a test of cognitive functioning with increasing age (7 years with four data collection points).

SETTING

In-home interviews were obtained from participants residing in the Southwest United States.

PARTICIPANTS

Participants were community-dwelling older Mexican Americans.

MEASUREMENTS

Cognitive functioning was assessed at each of the four data collection points with the Mini-Mental State Examination. Participants' self-reports of health functioning and smoking status were obtained at baseline.

RESULTS

With the inclusion of health variables and other control variables, the effect of smoking status on cognitive functioning was significant such that the decrease in the number of correct responses over time was greater for smokers than for nonsmokers.

CONCLUSIONS

Smoking increases risk for CD among community-dwelling older Mexican Americans. There are numerous health benefits in quitting smoking, even for older adults who have been smoking for many years. Further efforts to ensure that smoking cessation and prevention programs are targeted toward Hispanics are necessary.

Distribution of etiologies in patients above and below age 45 with first-ever ischemic stroke

BACKGROUND

There is limited information about distribution of etiologies of ischemic stroke in different age groups.

MATERIALS AND METHODS

In this study, we applied the Trial of ORG 10172 in Acute Stroke Treatment (TOAST) classification in 87 patients aged < or = 45, and in 347 patients aged 46-60 years with first-ever ischemic stroke in order to follow the distribution of stroke etiologies in different age groups.

RESULTS

Traditional risk factors, except smoking and atrial fibrillation, were more frequent in older patients. The most frequent etiologies in the younger stroke patients (aged < or = 45) were 'other' than routine causes (26.4%), cardioembolism (22.4%) and 'idiopathic' strokes (20.7%), when no cause was found. In older patients (aged 46-60), small vessel disease (25.1%) and cardioembolism (22.2%) were the most frequent etiologies of stroke.

CONCLUSIONS

In stroke patients below the age of 45, the TOAST classification should be expanded to better classify the wide diversity of stroke etiologies. The relatively low frequency of routine stroke etiologies in patients aged < or = 45 can be explained by the significantly lower prevalence of traditional risk factors in these patients. In patients 46-60 years old, the TOAST classification is adequate in the characterization of ischemic stroke etiologies.

Chronic cigarette smoking modulates injury and short-term recovery of the medial temporal lobe in alcoholics

Memory function is largely mediated by the medial temporal lobe (MTL), and its compromise has been observed in alcohol dependence and chronic cigarette smoking. The effects of heavy alcohol consumption and chronic smoking on hippocampal volumes and MTL metabolites and their recovery during abstinence from alcohol have not been assessed. Male alcoholics in treatment (ALC) [13 smokers (sALC) and 11 non-smokers (nsALC)] underwent quantitative magnetic resonance imaging and short-echo proton magnetic resonance spectroscopic imaging at 1 week and 1 month of sobriety. Outcome measures were compared with 14 age-matched, non-smoking light-drinkers and were related to visuospatial learning and memory. Over 1 month of abstinence, N-acetyl-aspartate, a neuronal marker, and membrane-associated choline-containing metabolites normalized in the MTL of nsALC subjects, but remained low in the MTL of sALC subjects. Metabolite concentration changes in both groups were associated with improvements in visuospatial memory. Hippocampal volumes increased in both groups during abstinence, but increasing volumes correlated with visuospatial memory improvements only in nsALC subjects. In summary, chronic cigarette smoking in alcohol-dependent men appears to have adverse effects on MTL metabolite recovery during short-term sobriety. These data may also have implications for other conditions with established MTL involvement and significant smoking co-morbidity, such as schizophrenia-spectrum and mood disorders.

Chronic cigarette smoking and heavy drinking in human immunodeficiency virus: consequences for neurocognition and brain morphology

Alcohol use disorders (AUD) and chronic cigarette smoking are common among individuals with human immunodeficiency virus infection (HIV). Concurrent AUD in HIV is related to greater abnormalities in brain morphology and neurocognition than either condition alone. However, the potential influence of chronic smoking on brain morphology and neurocognition in those concurrently afflicted with AUD and HIV has not been examined. The goal of this retrospective analysis was to determine if chronic smoking affected neurocognition and brain morphology in a subsample of HIV-positive non-treatment-seeking heavy drinking participants (HD+) from our earlier work. Regional volumetric and neurocognitive comparisons were made among age-equivalent smoking HD+(n=17), nonsmoking HD+ (n=27), and nonsmoking HIV-negative light drinking controls (n=27) obtained from our original larger sample. Comprehensive neuropsychological assessment evaluated multiple neurocognitive domains of functioning and for potential psychiatric comorbidities. Quantitative volumetric measures of neocortical gray matter (GM), white matter (WM), subcortical structures, and sulcal and ventricular cerebral spinal fluid (CSF) were derived from high-resolution magnetic resonance images. The main findings were (1) smoking HD+ performed significantly worse than nonsmoking HD+ on measures of auditory-verbal (AV) learning, AV memory, and cognitive efficiency; (2) relative to controls, smoking HD+ demonstrated significantly lower neocortical GM volumes in all lobes except the occipital lobe, while nonsmoking HD+ showed only lower frontal GM volume compared with controls; (3) in the HD+ group, regional brain volumes and neurocognition were not influenced by viremia, highly active antiretroviral treatment, or Center for Disease Control symptom status, and no interactions were apparent with these variables or smoking status. Overall, the findings suggested that the direct and/or indirect effects of chronic cigarette smoking created an additional burden on the integrity of brain neurobiology and neurocognition in this cohort of HIV-positive heavy drinkers.

Chronic Smoking Is Associated With Differential Neurocognitive Recovery in Abstinent Alcoholic Patients: A Preliminary Investigation

BACKGROUND

Approximately 50 to 90% of individuals in North America seeking treatment for alcoholism are chronic smokers. A growing body of evidence suggests that chronic cigarette smokers show a pattern of neurocognitive dysfunction similar to that observed in alcoholic patients. However, previous studies investigating neurocognitive recovery in abstinent alcoholic patients did not specifically consider the potential effects of chronic cigarette smoking.

METHODS

This study comprehensively compared longitudinal neurocognitive changes over 6 to 9 months of abstinence among 13 nonsmoking recovering alcoholic patients (ALC) and 12 actively smoking ALC. The neurocognitive performance of the alcoholic groups was compared with nonsmoking light-drinking controls (nonsmoking LD).

RESULTS

Nonsmoking ALC exhibited a significantly greater magnitude of longitudinal improvement than smoking ALC on measures of cognitive efficiency, executive skills, visuospatial skills, and working memory. Both nonsmoking ALC and smoking ALC demonstrated equivalent improvement on auditory-verbal learning, auditory-verbal memory, and processing speed. Nonsmoking LD showed no significant changes in neurocognition over time. In cross-sectional comparisons at 6 to 9 months of abstinence, nonsmoking ALC were superior to smoking ALC on measures of auditory-verbal learning, auditory-verbal memory, cognitive efficiency, executive skills, processing speed, and working memory. The longitudinal and cross-sectional neurocognitive differences observed between nonsmoking and smoking ALC remained significant after covarying for group differences in education, estimated premorbid intelligence alcohol consumption, and other potentially confounding variables. In smoking ALC, greater smoking severity was inversely related to longitudinal improvement on multiple neurocognitive measures.

CONCLUSIONS

These preliminary results suggest that chronic smoking may modulate neurocognitive recovery in abstinent alcoholic patients. More generally, chronic smoking may impact neurocognition in other conditions where is it a prevalent behavior.

Smoking and cognitive change from age 11 to 66 years: a confirmatory investigation

Previously we reported that smoking is associated with a small relative decline in cognition from childhood to old age. In this study we perform confirmatory analyses on a further wave of data collected from 298 of the participants, all with age 11 IQ scores, at age 66years, 2years after the original observations. Non-smokers scored a mean 4.9 memory test and 2.6 information processing speed test points and ex-smokers 3.5 memory test and 1.9 information processing speed test points higher than current smokers respectively over the two waves of testing, equivalent to 4-8% of mean test scores, adjusted for the effects of childhood IQ. Across tests a 100l/min higher Peak Expiratory Flow Rate was associated with a 3-4% higher test score at ages 64 and 66years. These data confirm the adverse effect of smoking on information processing speed, and provide new evidence for a similar adverse effect on memory for people in their mid-sixties.

The association between telomere length, physical health, cognitive ageing, and mortality in non-demented older people

Telomeres are nucleo-protein complexes that protect the ends of chromosomes. The telomeric DNA component shortens each time a somatic cell replicates, eventually leading to cell senescence. Telomere length has been associated with morbidity and mortality rates from age-related diseases. We tested the hypotheses that mean peripheral blood leukocyte telomere length, at age 79 years, is associated with physical health at age 79, cognitive ability at age 79, lifetime cognitive change, smoking, alcohol consumption, social class in adulthood, and mortality in a cohort of people without dementia (the Lothian Birth Cohort 1921: LBC1921). There was a small, significant association between telomere length and verbal fluency (a test of executive function) before (r=-0.16, p=0.027) and after (r=-0.17, p=0.022) adjustment for mental ability at age 11. This might be a type 1 error. Otherwise, we find that telomere length in old age does not have a significant association with age-related physical and cognitive decline or mortality.

Neurocognitive consequences of cigarette smoking in young adults—a comparison with pre-drug performance

The present study examined effects of current and past regular cigarette smoking in young adult subjects. One hundred and twelve 17-21-year-old subjects, assessed since infancy, were evaluated using a battery of neurocognitive tests for which commensurate measures were obtained at 9-12 years of age, prior to the initiation of regular smoking. Smokers, determined by urinalysis and self-report, were categorized as heavy (>9 cigarettes per day) and light (<9 cigarettes per day) current smokers and former smokers, the latter having smoked cigarettes regularly in the past but not for at least 6 months. A third of the subjects were currently smoking cigarettes regularly with half of these being heavy smokers. Among former smokers, the average duration of smoking was slightly less than 2 years. Overall IQ, memory, processing speed, vocabulary, attention and abstract reasoning were the primary outcomes with comparisons being made between each of the three user groups and a control group who never smoked regularly. After accounting for potentially confounding factors including clinical assessment, marihuana use and pre-drug performance in the relevant cognitive domain, current regular smokers did significantly worse than non-smokers in a variety of cognitive areas predicated upon verbal/auditory competence including receptive and expressive vocabulary, oral arithmetic, and auditory memory. This impact of current smoking appears to behave in a dose-response and duration-related fashion. In contrast, former smokers differed from the non-smokers only in the arithmetic task. These results suggest that regular smoking during early adulthood is associated with cognitive impairments in selected domains and that these deficits may be reversed upon cessation. Together, the findings add to the body of evidence to be used in persuading adolescents and young adults against the initiation of smoking and, if currently smoking, the advantages of stopping.

Brain metabolite concentrations and neurocognition during short-term recovery from alcohol dependence: Preliminary evidence of the effects of concurrent chronic cigarette smoking

BACKGROUND

Longitudinal studies of brain tissue metabolite recovery in short-term abstinent alcoholics have primarily investigated the frontal lobes and cerebellum with variable results. Preliminary proton magnetic resonance spectroscopic imaging (1H MRSI) suggested that chronic cigarette smoking exacerbates alcohol-induced brain injury in 1-week abstinent alcoholics. However, the potential effects of chronic cigarette smoking on the recovery of alcohol-induced brain injury have not been studied.

METHODS

Multislice short-echo time 1H MRSI was used to measure longitudinal changes in common brain metabolites in 25 recovering alcohol-dependent individuals (RA), retrospectively assigned to smoking (n = 14) and nonsmoking (n = 11) subgroups. Recovering alcohol-dependent individuals in longitudinal analyses were studied after approximately 7 and 34 days of abstinence from alcohol. In cross-sectional analyses, 36 RA (19 smokers, 17 nonsmokers) with approximately 34 days of sobriety were compared with 29 light drinkers (LD). Relationships between neurocognition and metabolite concentrations in abstinent RA were also examined.

RESULTS

Over 1 month of abstinence from alcohol, RA, as a group, showed significant increases of regional N-acetylaspartate (NAA; marker of neuronal viability) and choline-containing compounds (Cho; marker of cell membrane synthesis/turnover) primarily in frontal and parietal lobes. These increases appeared to be driven by nonsmoking RA. Cross-sectional results indicate that metabolite levels in RA at 35 days of sobriety are not significantly different from those in LD in most regions, except for lower NAA and Cho in parietal WM and subcortical structures. However, metabolite levels at that time appear to be strongly modulated by smoking status. The patterns of metabolite-neurocognition relationships were different for nonsmoking and smoking RA.

CONCLUSIONS

Within the first weeks of sobriety, regional brain NAA and Cho levels increased, but metabolite levels did not normalize in all brain regions after 35 days of sobriety. Neurobiologic recovery in RA appeared to be adversely affected by chronic smoking. Greater consideration of the effects of continued cigarette smoking on the neurobiologic and neurocognitive recovery of alcohol-dependent individuals is warranted.

A comparison of neurocognitive function in nonsmoking and chronically smoking short-term abstinent alcoholics

Approximately 70-90% of individuals in North America seeking treatment for alcoholism are chronic smokers. A growing body of evidence suggests chronic cigarette smoking alone adversely affects neurocognition in adults. However, few studies on the neurocognitive function of short-term abstinent alcoholics have specifically considered the potential effects of chronic cigarette smoking. In this study, 20 nonsmoking recovering alcoholics (nsRA) and 22 actively smoking recovering alcoholics (sRA) participants, matched on age and education, were contrasted on a comprehensive neurocognitive battery after 34+/-9 days of abstinence. nsRA were superior to sRA on measures of auditory-verbal learning and memory, processing speed, cognitive efficiency, and static postural stability. These group differences were not a function of group disparities in age, education, estimated premorbid verbal intelligence, lifetime alcohol consumption, or other measured comorbid psychiatric or medical factors. In sRA, longer smoking duration was negatively correlated with executive skills, visuospatial learning, general cognitive efficiency, and static postural stability. These results indicate that greater consideration of the potential neurobiological effects of current chronic smoking on neurocognitive functioning is warranted in studies of alcoholism and other conditions where smoking is a common comorbid factor.

Relationship between Lifetime Smoking, Smoking Status at Older Age and Human Cognitive Function

Cigarette smoking is a major risk factor for clinical cardiovascular disease and may also be associated with poorer cognitive functioning in older age. We measured lifetime cigarette smoking, smoking status and cognitive function in over 2,000 men and women from the general population aged over 50 years with subclinical atherosclerosis (ankle brachial pressure index<or=0.95 but no history of clinical cardiovascular disease). In this population, an association was found between greater lifetime smoking and poorer cognitive function in men and between smoking cessation and better cognitive function in women. The former relationship appeared to reflect an association between smoking habit and prior cognitive function (in early life), whereas the latter remained significant after adjustment for tests of crystallised cognitive function, suggesting a relationship between continuing to smoke (as opposed to quitting) and age-related cognitive decline. Both relationships were independent of the degree of atherosclerosis (as measured using the ankle brachial pressure index), suggesting alternative underlying mechanisms for the association between smoking and human adult cognitive function.

Quantitative brain MRI in alcohol dependence: preliminary evidence for effects of concurrent chronic cigarette smoking on regional brain volumes

BACKGROUND

Recent in vivo research using magnetic resonance spectroscopy demonstrated that chronic cigarette smoking exacerbates regional chronic alcohol-induced brain injury. Other studies associated cigarette smoking with gray matter volume reductions in healthy adults, with greater brain atrophy in aging, and with poorer neurocognition. Although cigarette smoking is common among alcohol-dependent individuals, previous research did not account for the potential effects of chronic smoking on regional brain volumes in alcoholism.

METHODS

High-resolution T1-weighted magnetic resonance images from one-week-abstinent, alcohol-dependent individuals and light drinkers were automatically segmented into gray matter, white matter, and cerebral spinal fluid of lobes and subcortical structures. A brief neuropsychological test battery was used to assess cognition in alcohol-dependent individuals. The alcoholic and nondrinking groups were retrospectively divided into chronic smokers and nonsmokers, and the volumetric data were analyzed as a function of alcohol and smoking status.

RESULTS

Chronic alcohol dependence was associated with smaller volumes of frontal and parietal white matter, parietal and temporal gray matter, and thalami, accompanied by widespread sulcal but not ventricular enlargements. Chronic cigarette smoking was associated with less parietal and temporal gray matter and with more temporal white matter. Among alcoholics, better visuospatial learning and memory and greater visuomotor scanning speed were correlated with larger lobar white matter volumes in the nonsmoking alcohol-dependent group only.

CONCLUSIONS

These data provide preliminary evidence that comorbid chronic cigarette smoking accounts for some of the variance associated with cortical gray matter loss and appears to alter relationships between brain structure and cognitive functions in alcohol-dependent individuals.

Cigarette smoking exacerbates chronic alcohol-induced brain damage: a preliminary metabolite imaging study

BACKGROUND

Cigarette smoking is common among alcohol-dependent individuals. Nevertheless, previous research has typically not accounted for the potential independent or compounding effects of cigarette smoking on alcohol-induced brain injury and neurocognition.

METHODS

Twenty-four 1-week-abstinent recovering alcoholics (RAs; 14 smokers and 10 nonsmokers) in treatment and 26 light-drinking controls (7 smokers and 19 nonsmokers) were compared on measures of common brain metabolites in gray matter and white matter of the major lobes, basal ganglia, midbrain, and cerebellar vermis, obtained via multislice short-echo time proton magnetic resonance spectroscopic imaging. Smoking and nonsmoking RAs were also contrasted on measures of neurocognitive functioning, as well as laboratory markers of drinking severity and nutritional status.

RESULTS

Chronic alcohol dependence, independent of smoking, was associated with lower concentrations of frontal N-acetylaspartate (NAA) and frontal choline-containing compounds, as well as lower parietal and thalamic choline. Smoking RAs had lower NAA concentrations in frontal white matter and midbrain and lower midbrain choline than nonsmoking RAs. A four-group analysis of covariance also demonstrated that chronic cigarette smoking was associated with lower midbrain NAA and choline and with lower vermian choline. In smoking RAs, heavier drinking was associated with heavier smoking, which correlated with numerous subcortical metabolite abnormalities. The 1-week-abstinent smoking and nonsmoking RAs did not differ significantly on a brief neurocognitive battery. In smoking RAs, lower cerebellar vermis NAA was associated with poorer visuomotor scanning speed and incidental learning, and in nonsmoking RAs lower vermis NAA was related to poorer visuospatial learning and memory.

CONCLUSIONS

These human in vivo proton magnetic resonance spectroscopic imaging findings indicate that chronic cigarette smoking exacerbates chronic alcohol-induced neuronal injury and cell membrane damage in the frontal lobes of RAs and has independent adverse effects on neuronal viability and cell membranes in the midbrain and on cell membranes of the cerebellar vermis. Higher smoking levels are associated with metabolite concentrations in select subcortical structures. Greater consideration of the potential effects of comorbid cigarette smoking on alcohol-induced brain damage and other diseases affecting the central nervous system is warranted.

Childhood IQ, smoking, and cognitive change from age 11 to 64 years

We investigated whether smoking is a risk factor for relative cognitive decline from age 11 to 64 years. The potentially confounding effects of childhood IQ, occupational status, level of education, presence of heart disease, hypertension, and lung function were examined. Subjects were nondemented and living independently. They were all born in 1936, had been participants in the same Scottish national IQ survey in 1947, and were reexamined at age about 64 years in 2000-2002. Current smokers and nonsmokers had significantly different mental test scores at age 64. This difference remained after adjustment for childhood IQ. Multiple linear regression identified childhood IQ, level of education, occupational code, lung function, and smoking history as significant independent predictors of mental function at age 64. In this sample, smoking makes a small (<1% variance) independent negative contribution to cognitive aging.