Lifestyle Factors and the Male Cognitive Function - Literature review Example

Smoking, Drinking and Other Lifestyle Factors and Cognitive Function in Men in the Caerphilly Cohort”- Review Cognitive function is one of the many human faculties that are affected because of aging. Many diseases such as Alzheimer’s, Parkinson’s, etc. that are associated with old age have a direct affect on the brain and on the ability to reason, communicate and solve problems. Also, oxygen to the brain and cerebral blood flow are a determining factor in how the brain works. The article in review focuses on how smoking, drinking and other lifestyle factors have an influence on the cognitive function in men 55-69 years of age who were part of the Caterphilly Cohort study of possible Heart Disease and Stroke, presented as a cross-sectional study thereof that can also serve to tie in factors such as diseases of the elderly and cerebral oxygen and blood flow, as observed in other, similar studies that have made reference to this one on numerous occasions throughout the years that it was published. For now, focussing on the article in mention, Elwood (et al, 1999) state, “Current cigarette smokers gave lower test cognitive function scores than either men who had never smoked, or ex-smokers. There was however no evidence of any gradient in function with the total lifetime consumption of tobacco. Age and social class show strong associations with cognitive function. Leisure pursuits and social contact are also both positively associated. Neither tobacco smoking nor the drinking of alcohol seem to be associated with cognitive function, though there is evidence suggestive of self selection of both men who had never smoked and ex-smokers.” The study, though, fails to mention an important observation with regard to alcohol. It does not address the consequences of heavy drinking and alcoholism on the human body and, more specifically, the brain and its functions, and it also does not say anything about the way cognitive function operates when under the influence. At the risk of stating the obvious, drinking too much alcohol will affect the motor responses, reflexes and thinking abilities of people at any age. For people who constantly drink, their cognitive capacities would obviously be seriously undermined not only while under the effect of alcohol, but also in the aftermath of a binge (the “hangover”). More specifically with regard to the study in question, excessive consumption of alcohol has been directly linked to dementia, so much so that this type of dementia has been labelled “alcoholic dementia”, which is virtually ignored in this study although dementia directly affects the mental and emotional workings of the human mind. The study also indicates that “There was no significant association between alcohol consumption and cognitive function, though ex-drinkers had markedly lower test scores than either current drinkers or men who had never drunk alcohol. This seemed probably to be a consequence of a high prevalence of illness among the ex-drinkers.” This is an ambiguous statement at best, which disregards the fact that many of the ex-drinkers could have quit drinking precisely due to health problems produced by alcohol that led to their illnesses –and consequent reduction in cognitive performance- in the first place. So the study only deals with “moderate drinking” and with “the lifetime consumption of tobacco” (note that it does not specify what type of consumption; this could also include chewing tobacco and other forms of tobacco consumption that do not necessarily involve smoking), also failing to address the issue of temporary cognitive function loss due to lack of oxygen to the brain, the latter being one of the symptoms of many lung diseases typically caused by smoking. However, a study by Rogers et al (1985) indicates that “elderly individuals who have smoked for three to four decades can benefit substantially by abstaining from cigarette smoking and that significant improvement in cerebral circulation occurs within a relatively short period.” The article subject-matter of this review somewhat corroborates these findings in quoting from Rogers that a negative and continuous relationship had been found between cerebral blood flow and smoking and drinking habits, although it fails to analyze this further or contribute with any new findings to that regard. Another article by Cervilla et al (2000) that makes reference to the one currently under review coincides with Rogers’ study in stating that “smoking seems to be a prospective risk factor for incident cognitive impairment; thus encouragement of older people to stop smoking could be considered as part of a strategy to reduce the incidence of cognitive impairment.” In evaluating effects on the moderate drinker, the article expressly states that “There is certainly no evidence in our data to support the conclusion drawn from the smaller Zutphen cohort that alcohol intake is protective against cognitive decline.” However, the article fails to definitively state whether moderate alcohol intake has a negative effect on cognitive performance, at best indicative of the fact that further studies on the subject are necessary. Another thought-provoking study finds that “in women, up to one drink per day [of an alcoholic beverage] does not impair cognitive function and may actually decrease the risk of cognitive decline.” (Stampfer et al, 2005). This is important as it would seem to be indicative, as mentioned in other studies regarding alcohol and cognitive performance, that moderate alcohol consumption increases the circulation of blood to, from and in the brain although, conversely, a study performed by Rogers et al 22 years prior had indicated that the chronic consumption of alcohol reduced regional cerebral blood flow. Another study that, at first glance, would seem to be somewhat contradictory found that “alcohol consumption has been associated with complex changes in cerebral vasculature and structure in older adults. How alcohol consumption affects the incidence of dementia is less clear. [In determining] the prospective relationship of alcohol consumption and risk of dementia among older adults, [...] a trend toward greater odds of dementia associated with heavier alcohol consumption was most apparent among men and participants with an apolipoprotein E 4 allele [a lipoprotein sometimes present in the human brain]. We found generally similar relationships of alcohol use with Alzheimer disease and vascular dementia. Compared with abstention, consumption of 1 to 6 drinks weekly is associated with a lower risk of incident dementia among older adults.” (Kenneth et al, 2003). Hence the foregoing would indicate that heavy alcohol consumption affects cognitive performance negatively and that moderate drinking (1 to 6 drinks a week) has a more positive effect on cognitive function than not drinking at all. Another study adamantly states that “current smokers aged >75 years perform more poorly on cognitive tests and appear to decline in memory more rapidly than their peers who do not smoke, especially if they lack the APOE-4 allele [a lipoprotein sometimes present in the human brain]” going on to sustain that “smoking does not affect cognitive performance in those persons aged less than 75 years.” (Reitz, et al, 2005). However, this would be contradictory to the findings of Elwood et al’s article which specifically mentions the fact that the study’s subjects were aged 55 to 69, and to the studies performed by Rogers et al. As for social interaction and its effects on cognitive performance, the general consensus of the article and other studies performed is that they are positive. An interesting study performed by Glei et al (2005) of elderly Taiwanese, which began in 1989 and cites the study presently under scrutiny, suggests that “despite a social structure where elderly persons often live with their children and social interaction is likely to be more family-centred than in western countries, data from Taiwan suggest that participation in social activities outside the family may have a bigger impact on cognitive function than social contacts with family or non-relatives.” This coincides to some degree with Elwood et al’s statement that social contact is positively associated with cognitive function, although it does not make the distinction between family and non-relatives. The article also concludes that the pursuit of intellectual activities positively contributes to cognitive performance over time, showing the strongest relationship with the cognitive tests and, especially, the AH4, a test applied to determine reasoning ability. This is corroborated by several other studies, including the one carried out by Richards et al in 2003, whose findings included the assertion that “participation in cognitively complex or social leisure activities has an independent association with adult cognition, suggesting that seeking mental stimulation may have a beneficial effect on cognition in middle age.” Other results in the article would indicate that social class and the education level are other lifestyle factors that make an important contribution to cognitive performance over time, and the studies of both Rotterdam (Breteler et al, 1994) and Huppert et al (1995) which are cited by Elwood suggest that these factors go hand in hand in that they are closely similar to each other, with social class being specifically related to language and perception, and education being associated to language and abstract thinking (Huppert). In a study performed by Turrell et al (2002) that also references the current article by Elwood et al “the influence of childhood and adult socioeconomic position, socioeconomic mobility, and cumulative disadvantage across the lifecourse on cognitive function in late middle age” was examined. “[Those] from poor childhood backgrounds, and those who attained a limited education and earned a low income, performed worst on each test. Men who occupied a disadvantaged socioeconomic position in childhood and then experienced upward mobility over the lifecourse exhibited better cognitive performance than those with similar socioeconomic origins but limited or no upward mobility. Conversely, men from advantaged childhood backgrounds who later in life experienced downward mobility scored poorer on each cognitive test than their counterparts who remained in the most advantaged groups throughout the lifecourse. There was a strong, graded association between cumulative socioeconomic disadvantage and cognitive function: Men who occupied a low socioeconomic position during both childhood and adulthood scored worse on every test than those who occupied a high position at all points in their lives. “ What is more, another study links the lack of education with dementia and Alzheimer’s disease stating that both “are higher among adults with limited education, and the less educated perform poorer on cognitive function tests. Improvements in both parental socioeconomic circumstances and the educational attainment of their offspring could possibly enhance cognitive function and decrease risk of dementia later in life.” (Kaplan et al, 2001). Having examined this article, its references and other articles that refer to it, the conclusion that can be reached is that, despite the many studies that have been performed regarding the effects of lifestyle factors and, more particularly, smoking and drinking, on cognitive performance over time, its findings are by no means definitive. Further studies are necessary to allay any doubt as to what effect substance abuse may have on cognitive performance later in life, and what precisely are its long-lasting consequences. Works Cited Breteler MMB, Claus JJ, Grobee DE, et al. (1994). “Cardiovascular disease and distribution of cognitive function in elderly people: the Rotterdam study.” BMJ. Accessed 25 Jan 2006. Cervilla, J.A., et al. (2000). “Smoking, drinking, and incident cognitive impairment: a cohort community based study included in the Gospel Oak Project.” Journal of Neurology, Neurosurgery and Psychiatry. Accessed 25 Jan 2006. Elwood, PC, et al. (1999). “Smoking, Drinking and Other Lifestyle Factors and Cognitive Function in Men in the Caerphilly Cohort.” Journal of Epidemiology and Community Health. Glei, D. et al. (2005). “Participating in social activities helps preserve cognitive function: an analysis of a longitudinal, population-based study of the elderly.” International Journal of Epidemiology. Accessed 23 Jan 2006. Huppert FA, Brayne C, Gill C, et al. (1995). “CAMCOG - A concise neuropsychological test to assist dementia diagnosis: sociodemographic determinants in an elderly population sample.” British Journal of Clinical Psychology. Accessed 25 Jan 2006. Kaplan, G, et al. (2001). “Childhood socioeconomic position and cognitive function in adulthood.” International Journal of Epidemiology. Accessed 25 Jan 2006. Kenneth, J. et al. (2003). “Prospective Study of Alcohol Consumption and Risk of Dementia in Older Adults.” Journal of the American Medical Association. Accessed 22 Jan, 2006. < http://jama.ama-assn.org/cgi/content/abstract/289/11/1405> Reitz, C. et al. (2005). “Effect of smoking and time on cognitive function in the elderly without dementia.” Neurology. Accessed 23 Jan 2006. Richards, M. et al. (2003). “Leisure activities and cognitive function in middle age: evidence from the Whitehall II study.” Journal of Epidemiology and Community Health. Accessed 23 Jan 2006. < http://jech.bmjjournals.com/cgi/content/abstract/57/11/907> Rogers, R.L., et al. “Abstention from cigarette smoking improves cerebral perfusion among elderly chronic smokers.” Journal of the American Medical Association. Vol. 253 No. 20, May 24, 1985. Stampfer, M., et al. (2005). “Effects of Moderate Alcohol Consumption on Cognitive Function in Women.” Journal of Medicine. Accessed 22 Jan 2006. < http://content.nejm.org/cgi/content/abstract/352/3/245> Turrell, G., et al. (2002). “Socioeconomic Position Across the Lifecourse and Cognitive Function in Late Middle Age.” The Journals of Gerontology Series B: Psychological Sciences and Social Sciences. Accessed 25 Jan 2006. Read More