Cognitive function in drinkers compared to abstainers in the New Mexico elder health survey

Midlife alcohol consumption and later life cognitive impairment: Light drinking is not protective and APOE genotype does not change this relationship

INTRODUCTION

Much debate exists about the role of light to moderate alcohol intake and subsequent cognitive function. The apolipoprotein E genotype may modify the relationship.

METHODS

Using data from the Honolulu-Asia Aging Study, a longitudinal population-based cohort (n = 2,416), Cox proportional hazards regression analyses were performed to measure midlife alcohol intake (average age = 52 years) and later life cognitive function (average age = 87 years) and to explore the role of apolipoprotein E genotype.

RESULTS

No protective effect of light drinking (>1 drink/month- 1 drink/day) or moderate drinking (>1-2 drinks/day) was observed in the cohort in adjusted models (HR = 1.013, CI:0.88-1.16; HR = 1.104, CI:0.91-1.34, respectively). Heavy drinking (>2-4 drinks/day) and very heavy drinking (>4 drinks/day) increased the risk for incident moderate cognitive impairment (HR = 1.355, CI:1.09-1.68; HR = 1.462, CI:1.04-2.05, respectively). When examining the relationship by apolipoprotein E ε4 carrier status, a similar dose-response pattern was observed in both groups with higher hazard ratios for those carrying at least one copy of the apolipoprotein E ℇ4 allele. As alcohol level increased, the age at incident moderate cognitive impairment decreased, especially among those with at least one apolipoprotein E ℇ4 allele.

DISCUSSION

We did not observe a significant protective effect for light to moderate drinking in midlife and subsequent cognitive impairment in this cohort. Heavy drinking increased the risk for moderate cognitive impairment and decreased the age at incidence, as did carrying at least one allele of the apolipoprotein E ℇ4 gene.

Interaction between Alcohol Consumption and Apolipoprotein E (ApoE) Genotype with Cognition in Middle-Aged Men

OBJECTIVE

Heavy alcohol consumption is associated with poorer cognitive function in older adults. Although understudied in middle-aged adults, the relationship between alcohol and cognition may also be influenced by genetics such as the apolipoprotein (ApoE) ε4 allele, a risk factor for Alzheimer's disease. We examined the relationship between alcohol consumption, ApoE genotype, and cognition in middle-aged adults and hypothesized that light and/or moderate drinkers (≤2 drinks per day) would show better cognitive performance than heavy drinkers or non-drinkers. Additionally, we hypothesized that the association between alcohol use and cognitive function would differ by ApoE genotype (ε4+ vs. ε4-).

METHOD

Participants were 1266 men from the Vietnam Era Twin Study of Aging (VETSA; M age = 56; range 51-60) who completed a neuropsychological battery assessing seven cognitive abilities: general cognitive ability (GCA), episodic memory, processing speed, executive function, abstract reasoning, verbal fluency, and visuospatial ability. Alcohol consumption was categorized into five groups: never, former, light, moderate, and heavy.

RESULTS

In fully adjusted models, there was no significant main effect of alcohol consumption on cognitive functions. However, there was a significant interaction between alcohol consumption and ApoE ε4 status for GCA and episodic memory, such that the relationship of alcohol consumption and cognition was stronger in ε4 carriers. The ε4+ heavy drinking subgroup had the poorest GCA and episodic memory.

CONCLUSIONS

Presence of the ε4 allele may increase vulnerability to the deleterious effects of heavy alcohol consumption. Beneficial effects of light or moderate alcohol consumption were not observed.

Risk Factors for Depression in Empty Nesters: A Cross-Sectional Study in a Coastal City of Zhejiang Province and China

The elderly are susceptible to depression, especially empty nesters. This study investigated the risk factors associated with depression in empty nesters. The participants were selected via multi-stage random cluster sampling. Depression symptoms were assessed using the Geriatric Depression Scale. The questionnaire surveyed demographic characteristics, underlying diseases, behaviors and lifestyles, negative life experiences, social support, self-care ability, etc. Chronic health conditions, such as being overweight/obese, smoking cessation, cancer, and chronic pain, as well as negative life experiences, such as the death of a loved one and financial loss, increased the risk of depression in empty nesters. In addition, the incapability of performing self-care also increased the risk of depression in empty nesters. The prevalence of depression in empty nesters was high. Being overweight/obese, cancer, chronic pain, smoking cessation, the death of a loved one, financial loss, and the incapability to deliver self-care were risk factors for depression in empty nesters. It is recommended that comprehensive measures be taken to enhance health interventions for this population, including encouraging a proper diet and physical activity for weight control, providing psychological counseling after negative life experiences, and teaching correct methods of smoking cessation.

Lifetime alcohol use and cognitive performance in older adults

Substance use is an important clinical issue in the older adult population. As older adults are susceptible to cognitive disorders, the intersection of the fields of substance use and cognitive neuroscience is an active area of research. Prior studies of alcohol use and cognitive performance are mixed, and inconsistencies may be due to under- or over-adjustment for confounders. This article adds to this literature by conducting a secondary analysis of self-reported lifetime history of alcohol use and cognitive performance in older adults (n = 133). It was hypothesized that current alcohol users would have poorer cognitive performance compared to never/minimal and former alcohol users. Older adult participants were classified into never/minimal alcohol users, former alcohol users, and current alcohol users. A neurocognitive battery included a global cognitive measure and individual measures of attention, memory, fluency, and executive function. A directed acyclic graph-based approach was used to select variables to be included in the multiple linear regression models. Though unadjusted analyses showed some significant associations between alcohol use and cognitive performance, all associations between alcohol use and cognitive performance were eliminated after adjusting for age, education, sex, race, and smoking pack years. Alcohol drink years were not significantly associated with cognitive performance among current and former alcohol users. These results suggest that lifetime alcohol use is not significantly associated with cognitive performance in older adults after adjustment for key confounders. Inconsistencies in prior studies may be due to uncontrolled confounding and/or unnecessary adjustment of mediators and/or colliders.

Midlife Alcohol Consumption and Risk of Dementia Over 43 Years of Follow-Up: A Population-Based Study From the Swedish Twin Registry

BACKGROUND

Midlife alcohol consumption (beer, wine, and spirits) was examined in relation to dementia incidence over 43 years.

METHODS

Participants were 12,326 members of the population-based Swedish Twin Registry born during 1907-1925 who responded to items about alcohol consumption in 1967/1970, subsequently classified as nondrinking (0 grams of ethanol per day), light (1-5g/d), moderate (5-12g/d), heavy (12-24g/d), and very heavy (>24g/d) drinking. Dementia was identified from the National Patient and Cause of Death Registries. Cox proportional hazard models adjusted for cluster-correlated data were used in cohort analyses. Conditional logistic regression (dementia-discordant pairs) and mixed effects models (dementia-concordant pairs) were used in twin analyses.

RESULTS

Overall, nondrinkers did not differ from light drinkers in dementia risk. Heavy drinking (hazard ratio = 1.10, p = .028) and very heavy drinking (hazard ratio = 1.18, p = .033) were associated with increased dementia risk controlling for sociodemographic, lifestyle, and cardiovascular factors. More alcohol from spirits was related to increased risk of dementia, whereas more alcohol from wine with decreased risk, although the association for wine reversed direction at high amounts. Relative to co-twins drinking light amounts, moderate-to-heavy drinking twins had (a) greater risk of dementia by 57% (p = .006, 300% in monozygotic pairs only) and (b) reduced time to dementia by 4.76 years (p = .019, 4.78 years in monozygotic pairs only).

CONCLUSION

Averaging more than 12 grams of alcohol per day may increase risk of dementia. Alcohol from spirits appears particularly important for the increased dementia risk. Genetic and/or familial factors do not explain these associations. Alcohol use reduction may be a useful population-wide intervention strategy.

The alcohol paradox: light-to-moderate alcohol consumption, cognitive function, and brain volume

BACKGROUND

Studies of older persons show consumption of light-to-moderate amounts of alcohol is positively associated with cognitive function and, separately, is negatively associated with total brain volume (TBV). This is paradoxical as generally, cognitive function is positively associated with TBV. We examined the relationships of TBV, global cognitive function (GCF), and alcohol consumption in a population-based cohort of 3,363 men and women (b. 1907-1935) participating in the Age Gene/Environment Susceptibility-Reykjavik Study (2002-2006) and who were free of dementia or mild cognitive impairment

METHODS

Drinking status (never, former, and current) and current amount of alcohol consumed were assessed by questionnaire. GCF is a composite score derived from a battery of cognitive tests. TBV, standardized to head size, is estimated quantitatively from brain magnetic resonance imaging.

RESULTS

Among women and not men, adjusting for demographic and cardiovascular risk factors, current drinkers had significantly higher GCF scores than abstainers and former drinkers (p < .0001); and GCF was associated with amount consumed. TBV was not associated with drinking status or amount consumed in men or women. GCF and TBV did significantly differ in their associations across alcohol categories (p interaction < .001). Within categories of alcohol intake, GCF and TBV were positively associated.

CONCLUSIONS

The difference in associations of alcohol intake to brain structure and function suggests there may be unmeasured factors that contribute to maintaining better GCF relative to TBV. However, at higher levels of reasonable alcohol consumption, there may be factors leading to reduced brain volume.

Shades of Grey: The Need for a Multi-disciplinary Approach to Research Investigating Alcohol and Ageing

This paper calls for an increase in multi-disciplinary research on the issue of alcohol and ageing, to ensure public health interventions reflect the complex and diverse needs of older drinkers. Older people (65+ years) represent a unique segment of the population; compared to adolescents and younger people, they are more likely to have a range of co-morbid conditions and be taking prescribed medication, and are more physiologically vulnerable to the effects of alcohol. This suggests that from a public health perspective, alcohol use by older people is problematic. However, as with younger people, alcohol use is closely associated with socialisation and social engagement. While social engagement is important at all stages of life, it is particularly critical as people age, when many of the formal social roles which provide a catalyst for social integration shift or are lost. Currently, however, there is little evidence of an integrated public health response to the complex issue of alcohol and ageing. That is, what is needed is a concurrent acknowledgement of the health problems that may be associated with contraindicated alcohol use, versus the potential health benefits that can accrue from social drinking. This will require a holistic rather than reductionist approach that integrates biomedical and social science insights to develop a more comprehensive and nuanced understanding of the implications of alcohol use amongst diverse populations of older people. Significance for public healthWith the rapid ageing of the global population and concerns about recent increases in the consumption of alcohol amongst older people, the issue of alcohol and ageing is becoming an important public health issue. However, there remains little research that adopts a holistic multi-disciplinary perspective. Such research is important and may offer the best way forward in terms of unravelling the complexity of competing risks and benefits associated with low to moderate drinking amongst older people.

Late-life alcohol consumption and cognitive function in elderly men

Moderate alcohol consumption (one to two drinks per day) has been associated with better cognitive function and lower risk of developing dementia in the elderly. In light of alcohol's well-known neurotoxic properties, more evidence from well-controlled population-based studies is required. The objective of this study was to examine whether self-reported alcohol intake at age 70 is linked to cognitive function (assessed by trail making tests (TMTs) A and B, which are measures of attention, mental speed, and flexibility) in a population-based cohort consisting of 652 cognitively healthy elderly men. Linear regression models were used to assess both cross-sectional (i.e., age 70) and prospective (i.e., age 77) associations between alcohol intake and cognitive function. The analyses were adjusted for education, body mass index, energy intake, self-reported physical activity, smoking, a history of hypertension or diabetes, apolipoprotein E ε4 status, and cholesterol levels at the age of 70. Baseline data were obtained from 1990 to 1996. Self-reported alcohol intake (mean 6.9 ± 7.1 g/day) was associated with better performance on TMT-B at ages 70 and 77 (β = -0.87, p < 0.001). In contrast, alcohol intake was not predictive of the difference in performance on these tests between ages 70 and 77. Despite cross-sectional associations with performance in a test of executive functioning, moderate intake of alcohol was not linked to differences in cognitive performance between ages 70 and 77 in the present study. Thus, our findings do not support the view that daily moderate alcohol consumption is a recommendable strategy to slow cognitive aging in elderly populations.

Alcohol consumption in mild cognitive impairment and dementia: harmful or neuroprotective?

OBJECTIVE

In several longitudinal studies, light-to-moderate drinking of alcoholic beverages has been proposed as being protective against the development of age-related changes in cognitive function, predementia syndromes, and cognitive decline of degenerative (Alzheimer's disease, AD) or vascular origin (vascular dementia). However, contrasting findings also exist.

METHOD

The English literature published in this area before September 2011 was evaluated, and information relating to the various factors that may impact upon the relationship between alcohol consumption and dementia or predementia syndromes is presented in the succeeding texts.

RESULTS

Light-to-moderate alcohol consumption may be associated with a reduced risk of incident overall dementia and AD; however, protective benefits afforded to vascular dementia, cognitive decline, and predementia syndromes are less clear. The equivocal findings may relate to many of the studies being limited to cross-sectional designs, restrictions by age or gender, or incomplete ascertainment. Different outcomes, beverages, drinking patterns, and study follow-up periods or possible interactions with other lifestyle-related (e.g., smoking) or genetic factors (e.g., apolipoprotein E gene variation) may all contribute to the variability of findings.

CONCLUSION

Protective effects of moderate alcohol consumption against cognitive decline are suggested to be more likely in the absence of the AD-associated apolipoprotein E ε4 allele and where wine is the beverage. At present, there is no indication that light-to-moderate alcohol drinking would be harmful to cognition and dementia, and attempts to define what might be deemed beneficial levels of alcohol intake in terms of cognitive performance would be highly problematic and contentious.

Diet and Alzheimer's disease risk factors or prevention: the current evidence

Preventing or postponing the onset of Alzheimer's disease (AD) and delaying or slowing its progression would lead to a consequent improvement of health status and quality of life in older age. Elevated saturated fatty acids could have negative effects on age-related cognitive decline and mild cognitive impairment (MCI). Furthermore, at present, epidemiological evidence suggests a possible association between fish consumption, monounsaturated fatty acids and polyunsaturated fatty acids (PUFA; in particular, n-3 PUFA) and a reduced risk of cognitive decline and dementia. Poorer cognitive function and an increased risk of vascular dementia (VaD) were found to be associated with a lower consumption of milk or dairy products. However, the consumption of whole-fat dairy products may be associated with cognitive decline in the elderly. Light-to-moderate alcohol use may be associated with a reduced risk of incident dementia and AD, while for VaD, cognitive decline and predementia syndromes, the current evidence is only suggestive of a protective effect. The limited epidemiological evidence available on fruit and vegetable consumption and cognition generally supports a protective role of these macronutrients against cognitive decline, dementia and AD. Only recently, higher adherence to a Mediterranean-type diet was associated with decreased cognitive decline, although the Mediterranean diet (MeDi) combines several foods, micro- and macro-nutrients already separately proposed as potential protective factors against dementia and predementia syndromes. In fact, recent prospective studies provided evidence that higher adherence to a Mediterranean-type diet could be associated with slower cognitive decline, reduced risk of progression from MCI to AD, reduced risk of AD and a decreased all-cause mortality in AD patients. These findings suggested that adherence to the MeDi may affect not only the risk of AD, but also of predementia syndromes and their progression to overt dementia. Based on the current evidence concerning these factors, no definitive dietary recommendations are possible. However, following dietary advice for lowering the risk of cardiovascular and metabolic disorders, high levels of consumption of fats from fish, vegetable oils, nonstarchy vegetables, low glycemic index fruits and a diet low in foods with added sugars and with moderate wine intake should be encouraged. Hopefully this will open new opportunities for the prevention and management of dementia and AD.

Moderate alcohol consumption and cognitive risk

We reviewed 143 papers that described the relationship between moderate drinking of alcohol and some aspect of cognition. Two types of papers were found: (1) those that provided ratios of risk between drinkers and nondrinkers (74 papers in total) and (2) those that, although they did not provide such ratios, allowed cognition in drinkers to be rated as "better," "no different," or "worse" than cognition in nondrinkers (69 papers in total). The history of research on moderate drinking and cognition can be divided into two eras: 1977-1997 and 1998-present. Phase I (1977-1997) was the era of neuropsychological evaluation involving mostly young to middle-aged (18-50 years old) subjects. Although initial studies indicated moderate drinking impaired cognition, many later studies failed to confirm this, instead finding no difference in cognition between drinkers and nondrinkers. Phase II (1998-present) was and is the era of mental status exam evaluation involving mostly older (≥55 years old) subjects. These studies overwhelmingly found that moderate drinking either reduced or had no effect on the risk of dementia or cognitive impairment. When all the ratios of risk from all the studies in phase II providing such ratios are entered into a comprehensive meta-analysis, the average ratio of risk for cognitive risk (dementia or cognitive impairment/decline) associated with moderate "social" (not alcoholic) drinking of alcohol is 0.77, with nondrinkers as the reference group. The benefit of moderate drinking applied to all forms of dementia (dementia unspecified, Alzheimer's disease, and vascular dementia) and to cognitive impairment (low test scores), but no significant benefit against cognitive decline (rate of decline in test scores) was found. Both light and moderate drinking provided a similar benefit, but heavy drinking was associated with nonsignificantly higher cognitive risk for dementia and cognitive impairment. Although the meta-analysis also indicated that wine was better than beer or spirits, this was based on a relatively small number of studies because most studies did not distinguish among these different types of alcohol. Furthermore, a number of the studies that did make the distinction reported no difference among the effects of these different types of alcohol. Therefore, at present this question remains unanswered. Analysis also showed that the presence of the apolipoprotein E epsilon 4 allele eliminated the benefit of moderate drinking. However, this was based on a relatively small number of studies and several other studies have found a beneficial effect of the epsilon e4 allele. Further studies are necessary to settle this question. The benefit of moderate alcohol for cognition was seen in both men and women, although the amount and pattern of drinking is very different between the two sexes. Lastly, the finding of unaffected or significantly reduced cognitive risk in light to moderate drinkers was seen in 14/19 countries for which country-specific ratio data were available, with three of the five remaining countries showing nonsignificant reductions as well. Overall, light to moderate drinking does not appear to impair cognition in younger subjects and actually seems to reduce the risk of dementia and cognitive decline in older subjects.

Alcohol use among older adults

Alcohol use is common in older adults and is associated with numerous health and social problems. Recent evidence suggests that in addition to level of alcohol consumption, drinking pattern may also be important. Moderate alcohol intake may confer some cardiac benefits, while heavy episodic drinking seems particularly problematic. Detecting alcohol misuse in older adults is difficult since clinical acumen is often poor, screening questionnaires have serious limitations and laboratory tests are not diagnostic. Brief alcohol interventions to reduce alcohol consumption appear useful in younger populations, but are less studied in older adults. While there is increasing research into the issue of alcohol use among older adults, clinicians and policy-makers must rely on limited evidence when making clinical decisions.

Chronic effects of low to moderate alcohol consumption on structural and functional properties of the brain: beneficial or not?

OBJECTIVE

Some studies suggest that the effects of low to moderate drinking (about 1-3 standard glasses of alcohol per day) on the brain and cognitive performance are positive. In the present study this hypothesis is investigated.

METHODS

For this purpose studies on the effects of low to moderate drinking on brain structure (Magnetic Resonance Induction (MRI) studies) and on cognitive performance were analysed and discussed

RESULTS

In MRI studies, a linear negative effect of alcohol consumption on brain volume was found. Furthermore, a linear decrease in grey matter concurring with a linear increase in white matter volumes as a function of number of drinks was reported in males, but not in females. Only in elderly low to moderate drinkers (aged > 65 years) there appeared to be an U-shaped relationship between alcohol consumption and white matter integrity (grade) on the one hand and cognition on the other hand.

CONCLUSIONS

The changes reported in brain shrinkage, grey matter and white matter volume, as a result of low to moderate alcohol consumption sooner offer support for the contention that such drinking decreases brain health than for its beneficial effect. An exception might hold for elderly light and moderate drinkers where less white matter damage was found than in abstainers concurring with better cognitive performance. However, methodological problems impose limits on this conclusion.

Race moderates age-related cognitive decline in type 2 diabetes

The age-related rate of cognitive decline in patients with diabetes mellitus has received relatively little attention. In this cross-sectional study, Caucasian (N = 145) and African American (N = 25) males with diabetes mellitus were recruited to examine age-related changes in cognitive performance. It is known that African Americans with diabetes mellitus are at increased risk for more frequent and more severe diabetes-related complications. It was hypothesized that such complications may accelerate age-related cognitive decline in African Americans. Three timed tests varying in complexity assessed attention, mental flexibility, and learning. Advancing age was uniformly associated with decreasing cognitive performance but only on more complex tasks did race moderate this relationship. A steeper age-related decline was observed in African Americans on more complex cognitive tests. Diabetes may be an accelerated form of aging that impacts cognition and race appears to differentially moderate this relationship.

Alcohol use and older adults: A little goes a long way

We examined the relationships between alcohol use, cognitive and affective variables, and the potential differential benefits of training for older adults drinkers and non-drinkers who participated in a randomized trial implemented between 2001-2006. Participants, who were living independently in the community, were randomly assigned to either twelve hours of memory training or health promotion classes. Outcomes included depression, health, cognition, verbal, visual, memory, and performance-based IADLs. The sample was 79% female, 17% Hispanic and 12% African-American. The typical participant had an average age of 75 years with 13 years of education. In the memory intervention group, there were 135 individuals (63 drinkers, 72 non-drinkers). In the health promotion condition, there were 129 individuals (58 drinkers and 71 non-drinkers). At baseline, drinkers scored higher on cognition, verbal memory, and lower on depression than non-drinkers. Alcohol use was positively related to physical health at baseline as measured by the Physical Component Summary Score of the Medical Outcomes Health Scale (SF-36). We found significant effects for the time*drinking*treatment group interaction in the repeated measures ANCOVA for the Mini Mental Status Examination, the Hopkins Verbal Learning Test, and the SF-36 Mental Health sub-scale. The time*drinking*group interactions were not statistically significant for any of the other outcomes; This study demonstrated that older adults benefited from targeted psychosocial interventions on affective, cognitive and functional outcomes. In addition, the SeniorWISE study provides empirical support to the research evidence emphasizing the health benefits of moderate alcohol consumption in older adults.

Alcohol intake, carotid plaque, and cognition: the Northern Manhattan Study

BACKGROUND AND PURPOSE

Moderate alcohol intake has been associated with better cognitive performance, implicating vascular and neurodegenerative processes. Few studies to clarify the importance of vascular disease have included direct measures of atherosclerosis or minority populations at higher risk of vascular disease and dementia.

METHODS

The Northern Manhattan Study includes stroke-free community based Hispanic (54%), black (25%), and white (22%) participants. We performed a cross-sectional study of alcohol intake and performance on the Mini-Mental State Examination (MMSE) in subjects with sonographic measurement of maximal carotid plaque thickness and adjusted for sociodemographic and vascular risk factors.

RESULTS

The median MMSE score was 27 (interquartile range 24 to 29; n=2215). Reported alcohol intake was divided into 5 groups: never (n=509), past (n=494), <1 drink/week (n=300), 1/week to < or =2 drinks/day (n=796), and >2 drinks/day (n=116). Drinking 1 drink weekly up to 2 daily was associated with better performance on the MMSE (odds ratio=1.19; 95% CI, 1.10 to 1.26) compared with nondrinkers in women (P< or =0.0001) but not in men, adjusting for sociodemographic and vascular risk factors. Maximal carotid plaque thickness (mean 1.1 mm; SD 1.2 mm) was not associated with alcohol intake and did not mediate the relationship between alcohol and cognition.

CONCLUSIONS

Moderate alcohol consumption was independently associated with better cognitive performance in women from this multiethnic sample. Carotid plaque was not a mediator of this association suggesting alcohol may impact cognition through a separate vascular or degenerative pathway.