PREDICTING STANDING HEIGHT FROM HEIGHT PROXIES FOR DETERMINATION OF BODY MASS (BMI) AND ANTHROPOMETRIC STATUS OF OLDER PERSONS IN TWO LOCAL GOVERNMENT AREAS OF ABIA STATE

4.4       Relationship between the BMI derived from standing

4.5       Socio-economic predictors of BMI calculated from

Reference

4.4        Relationship between the BMI derived From Standing Height and the BMI derived from the height Proxies used in the study 41

According to World Health Organization (1995), the elderly are defined as a group of people over 60 years of age. Older adults are the fastest growing segment in the world’s population and they are quite heterogeneous (Dart and Keller, 2009). Anthropometry is the science of measuring the size, weight and proportion of human body (Mahan and Escott-stump, 2004).Anthropometric measurements provide simple, non-invasive methods to assess the nutritional status of populations (Lucia et al., 2002). 

Anthropometric measurements are also part of the nutritional assessment which is an important component of health care. Measuring the individual's stature with accuracy is very important because it is a basis for estimating basal energy expenditure and consequent nutrient needs and to calculate indices of nutrient status (Kaweesak et al., 2012). However, common methods of nutritional anthropometric assessment are not entirely satisfactory for all elderly persons. Certain measurements such as stature may be difficult to obtain because of postural changes, thinning of the disks of the spinal column, and diminution in the height of the vertebrae, all of which are associated with aging (Kaweesak et al., 2012). Data may also be difficult to interpret due, in part, to individual differences in the effects of normal aging). BMI is an indicator for assessing risk of chronic energy deficiency (CED) and obesity and has become a universal index of energy nutritional status in adults even though it is influenced by many factors other than energy stores (Bogin and Beydoun, 2007). 

Height is an important clinically measured parameter along with BMI and body surface area calculation. Human height or stature is the distance front the bottom of the feet to the top of the head in a human body. Collins (2014) defined height as the distance from base to top.These measurements play an inevitable part in drug dose adjustment, nutrition assessment and requirements, as well as for risk stratification. The body Mass Index (BMI) has become a universal index of energy status in adults even through it is influenced by many factors order than energy stores (Bogin, 2005). Measurement of the height of patients is required for determination of basic energy requirement, standardization of measurement of physical capacity and for adjusting drug dosage (Bloomfield et al., 2006; Venkataraman et al., 2015). However, in some situations, the exact height cannot be determined directly because of deformities of limbs or in patient’s body who had undergone amputations. BMI is a widely used body weight classification system, but has known limitations, and much need to be adjusted for arm span, knee height and sitting height in order to be useful as an indicator of health risks in special populations (Guylaine et al., 2005). 

Malnutrition remains a major nutritional problem commonly found in groups of the elderly (Fatmah and Erwin, 2012). Older adults are the fastest growing segment in the world population and they are quite heterogeneous and they are recognized as a group at risk of malnutrition in the population as a whole (Dart and Keller, 2009). Therefore, early screening of elderly malnutrition is urgently needed in assessing nutritional status through the calculation of body mass index (BMI) with body weight and body height as indicators (Fatmah and Erwin, 2012). 

Many elderly persons, particularly the very old who are in the institutions, are chair bound or bedridden due to arthritis, disease or surgery (Gibson, 2005). For these non-ambulatory persons and for those who are unable to stand for examinations, collection of acceptable anthropometric data poses a problem. As we age, there are many biological changes in the body composition, although rate and consequences of changes vary greatly (Gibson, 2005). Because of these changes, older adults have an increased susceptibility to several chronic diseases that may be prevented or delayed through the provision of nutrition intervention (Wadhwa et al., 1997). However, appropriate interventions are dependent on comprehensive assessment of nutritional status which includes diet, biochemical, clinical and anthropometric information. Nutritional status is difficult to measure in any population, but it is especially difficult in older adults because dietary recalls may be inaccurate due to cognitive impairment, biochemical laboratory values may be skewed due to the presence of chronic diseases, clinical symptoms may be difficult to detect due to normal aging process. Anthropometry is often heavily relied on to determine nutritional status of older adults (Dart and Keller, 2009).But accurate anthropometric measurements in the elderly might be difficult to obtain because of changes in body composition, posture and mobility, which occur during the aging process (Lucia et al., 2002). In many older persons, the use of body mass index to determine the adult nutritional status is limited by the measurement of height, which is often unreliable, because of spinal deformities such as kyphosis, vertebral compressions in height and alterations in height and shape of the vertebral discs (Kwok and Whitelow, 1991). Postural changes such as bowing of the legs and bent knees due to decreased muscle strength might also lead to inaccurate height measurement (Pieterse, 1999). Most indices of nutritional status rely on accurate recording not only of body weight, but also of height (Cape et al., 2007). Accurate methods are therefore needed to assess the nutritional status of older people.

At present, there are no guidelines on the degree of spinal curvature beyond which measurement of height would be invalid, but there are obviously individuals whose height should not be measured using the usual methods (Cape et al., 2007). In such cases, height has to be estimated, or preferably another measurement could be used as a surrogate. Using standing height to calculate BMI in the elderly people could be inappropriate because of the reported height loss with ageing, resulting from the compression of vertebrae, kyphosis and osteoporosis (Hickson and Frost, 2003). A simple and reliable measure of height, especially in older people is therefore necessary. To deal with the difficulty of height measurement in the elderly, several height predictors such as knee height, arm span and sitting height can be used (Fatmah, 2010). Thus, there is need to explore the use of arm span, knee height and sitting height as proxy for height to assess the BMI of the elderly.

The general objective of the study is to Predict the Standing Height from Height Proxies for determination of Body Mass Index (BMI) and anthropometric status of older persons in two local government areas of Abia State.

The specific objectives were to:

Some anthropometric measurements with different positions may not be effective because of discomfort. Three anthropometric measurements as one tool like a chair can overcome the problems. The result of the study will provide the basis for developing an anthropometric chair (BMI meter) for the elderly nutritional status assessment with ease. 

The study will provide information that will help the community nutritionists, dietitians, home economist and those in related professions to gain knowledge on anthropometry, in determining the nutritional status of the elderly. The study will also be useful to health workers and nutritionists for them to know other height proxies that can be used for older persons who may not stand erect for height measurement.