January 10th, 2018
Obesity and aging – literature review
Increasing obesity cases in adults is among the threats to advances made in bettering life expectancy and population ageing (Byles, 2009). Many countries in the modern day face an increasing risk of obesity associated with trend towards urbanization, changes to global food availability, eating habits, and increasing sedentary lifestyles (Byles 2009, p.412). In the year 2000, the number of overweight and obese adults as reported by Caballero (2007) had surpassed those who were underweight (cited in Byles, 2009, p.413). Though obesity cases are higher in developed world where the risk factors are widespread, obesity has become a public health concern even in the developing world (Byles, 2009). In the developed world however, overweight and obesity cases are widespread among individuals across all age groups thus presenting a significant healthcare issue (Ogden, et al., 2006; Byles, 2009). Various studies have thus assessed the incidence and prevalence of obesity in the developed nations.
Ogden et al. (2006) for instance assessed the prevalence of overweight conditions in children and adolescents, and obesity in adults in the United States from 199 to 2004. Using a study sample of 3958 children and adolescents between the ages of 2 and 19, and 4431 adults above 20 years old, the study found out that 17.1 % of the children and adolescents were overweight and 32.2 % of the adults obese in the year 2003-2004 (Ogden et al., 2006, pp.1551-1553). This percentage was an increase from the respective values of 13.9% and 30.5% in the year 1999-2000 (Ogden et al., 2006, pp.1551-1553). The study used height and weight data obtained from the National Health and Nutrition Examination Survey (NHANES) to assess overweight and obesity cases according to the predefined Body Mass Index (BMI) values (Ogden et al., 2006). Overweight children and adolescents were for instance those whose BMI was “at or above the 95th percentile of the sex-specific … BMI for age growth charts” whereas an adult was considered obese when the BMI value was 30 or higher (Ogden et al., 2006, p.1549). Extreme obesity cases were those with BMI values equal to or higher than 40, with 4.8% and 3.0% representing extreme obese cases in total adult population and the adult population aged 60 and above respectively (Ogden et al., 2006, p.1549 & p.1553).
With these high cases of obesity noted in adults and the proportion of persons in old age (≥ 65 years) estimated to increase for most countries (UN 2009); the need to combat obesity in old age arises. The significance of obesity in the aged in the United States is evident from another study assessing adult obesity trends in the United states from the year 1999 to 2008 (Flegal, Carroll, Ogden & Curtin 2010). The study used 2007-2008 height and weight measurements data from NHANES which comprised of 5555 adult men and women aged 20 years and above, and compared these measurements with results for the years 1999 to 2006 (Flegal et al., 2010). For measurement outcomes, the study defined an individual as being overweight when the BMI value was 25.0 to 29.9, whereas a BMI of 30.0 or higher represented an obese condition (Flegal et al., 2010, p.238). The study findings indicated the age-adjusted prevalence of obesity at 95 % confidence interval to be 33.8% for the entire sample, 32.2% for men and 35.5% for women (Flegal et al., 2010, p.238). Irrespective of the gender, the prevalence rate for obesity varied according to the age group, and the ethnic and racial groupings (Flegal et al., 2010). With respect to Age group; both overweight (BMI ≥25) and obese (BMI≥30) conditions increased from younger age groups (20-39 years and 40-59 years) to the elder age group (≥60 years) except for women above 60 years whose obese cases were lower than those of the younger age groups (Flegal et al., 2010, p.236).
Increased obesity cases in old age adults necessitates increased attention due to various adverse health outcomes associated with obesity that bear the potential of increasing the cost of providing care to the aged population. Salihu, Bonnema and Alio (2009) for instance reviewed the health effects of obesity for the population aged 50 years and above in addition to estimating the prevalence of the condition in that age group. The study limited its review to studies published in PubMed (1996-2008) and Psychinfo (2002-2008) that focused on obesity or associated health conditions in either the 60+ age group (elderly) or the 50+ age group (pre-elderly). The review indicated that the increasing cases of obesity worldwide were independent of the social economic status of individuals and could lead to various health risks (Salihu et al., 2009). For instance, the reviewed literature suggested obesity in the elderly increased risk of morbidity factors such as cancers, hypertension, stroke, heart disease and metabolic syndrome (Salihu et al., 2009). Other adverse health outcomes associated with obesity as noted in the study are obstructive sleep apnea, disability, depression, Alzheimer’s disease and other cognitive decline conditions (Salihu et al., 2009). Such obesity-associated conditions increases the health costs for providing rightful care for the elderly thus increasing obesity cases among the elderly, could outstrip the capacity of nursing homes to effectively deal with such conditions (Salihu et al., 2009).
Further adverse effects of obesity in aging are in its influence on age-related oxidative stress. To exemplify such effects, Vassalle, Maffei, Ndreu and Mercuri (2009) evaluated the effect of obesity and smoking on age-related oxidative stress. The study estimated the oxidative-INDEX , a score comprising aspects of both oxidative and counterpart antioxidant properties in 179 subjects (50 males, 16-79 years of age) who had been pre-screened for acute or chronic cardiovascular, immunological and inflammatory disease or malignancy; conditions that could alter the study outcomes (Vassale et al., 2009). The study ordered subjects into obese, overweight and normoweight categories according to the BMI values, with BMI values above 30 denoting obese condition (Vassale et al., 2009). The results of the study indicated that obese subjects had a higher oxidative stress status as compared to overweight and normoweight subjects with oxidative-INDEX levels having a positive correlation to BMI values of the entire population (Vassale et al., 2009). With the relationship between oxidative stress and susceptibility to diseases, the results linking obesity to increased oxidative stress buttresses the challenge that obesity in old age presents to healthy aging and improved life expectancy (Vassale et al., 2009). In aging for instance, oxidative stress could be one of the processes through which progressive loss of functionality and subsequent progressive decline in biological function proceeds (Vassale et al., 2009). Such loss of biological function negatively affects various processes that are necessary for survival.
To address the issue of obesity in old age, a number of studies offer strategies that could reduce the prevalence of obesity among the elderly population. Apart from conventional therapies (reviewed in Clapham, Arch and Tadayonn 2001); various studies have provided insight into how obesity may be prevented, treated or managed in old age. One of the strategies that studies have argued to better the prevention of obesity in old age is physical activity. Dubnov et al. (2003) for instance reviewed the effects of physical activity on weight gain after menopause in order to provide strategies that would better obesity treatment during the menopause transition. The study first evaluates other relevant strategies used to achieve weight loss such as dieting and behavioral changes before providing the case for physical activity. Following the review on the effect of physical activity, various beneficial effects of its use in managing obesity in the elderly are highlighted. For instance, by engaging in physical activity, the elderly population could reduce their mortality risk resulting from the reduction in risks to other ailments such as hypertension, diabetes and dyslipidemia (Dubnov et al., 2003). Further, such physical activity bears the potential to significantly reduce the amount of abdominal obesity in elderly women, hinder accumulation of abdominal fats associated with aging process, and prevent weight gain (Dubnov et al., 2003). The review establishes that physical activity is to be a prudent way for ensuring sustainable weight loss within the elder generation without adversely affecting their health when appropriately structured (Dubnov et al., 2003). Optimally structured physical activity according to the study could involve 30 minutes of moderate intensity activities such as a brisk walk of 3.5 km each day (Dubnov et al., 2003). Alternatively, such 30 minutes could be a cumulative tally for a series of activities performed at different periods within the day such as gardening, playing with grand children or climbing stairs (Dubnov et al., 2003).
Expounding on the effects of physical activity on obesity in aging, Brach, VanSwearingen, FitzGerald, Storti and Kriska (2004) evaluated the association between physical activity, physical function and obesity. The study used 171 community-dwelling women with a mean age of 74.3 years who participated in a 14-year follow-up study to a trial on walking intervention (Brach et al., 2004). Obesity and physical activity measures were taken in 1982, 1985, 1995, and 199 using BMI and Modified Paffenbarger Questionnaire respectively whereas physical function was evaluated via the functional Status Questionnaire and gait speed in 1999 (Brach et al., 2004). The Study results suggested that physical activity increased physical function in obese women to a level equal that of older women with normal weight (Brach et al., 2004). Such study findings suggest that physical activity could confer significant beneficial health outcomes to obese subjects (Brach et al., 2004).
Future treatment for obesity cases could also lie in complementary and alternative medicine that has shown promise in various studies. Cherniack (2008) for instance assesses the potential that a number of alternative therapies used in weight loss could have in obesity treatment by reviewing studies that link these alternative therapies to weight reduction. Dietary supplements such as Conjugated Linoleic Acid (CLA) and chitosan provide one of the possible future treatments for obesity. In one of the reviewed studies on CLA, a double-blinded randomized assay of 180 men with a placebo control group indicated statistically significant weight losses with CLA administration as a triglyceride (Cherniack, 2008). Administration of CLA as free fatty acid however did not confer such beneficial effects to the subjects (Cherniack, 2008). Other complementary and alternative medicine approaches that show promise for obesity treatment in old age according to the review are botanicals such as tea extracts, and Garcinia cambogia fruit; acupuncture therapies and; hypnotherapy approaches (Cherniack, 2008). Lack of adequate clinical trials on such alternative therapies, methodological challenges in some of the studies returning a positive effect and mixed effects of suggested therapies under different experimental conditions however necessitate further evaluation of such therapies before their widespread use in obesity treatment for the elderly (Cherniack, 2008). Go to part 3 here.