Date Published: October 23, 2018
Publisher: Public Library of Science
Author(s): Marcos Felipe Silva de Lima, Larissa Praça de Oliveira, Natália Louise de Araújo Cabral, Laura Camila Pereira Liberalino, Ursula Viana Bagni, Kenio Costa de Lima, Clélia de Oliveira Lyra, Gary Liguori.
Estimating equations can be used when measuring the height of elderly persons is not possible. However, such methods are not always applicable; therefore, it is necessary to consider several aspects, such as sex, age, and ethnicity of the studied population to generate these equations. This study aimed to compare and validate methods of estimating the height of the Brazilian elderly nursing home residents. An accuracy study was conducted with 168 elderly persons. A total of 23 equations were quantitatively evaluated by plotting the differences in means, the Student’s t-test for paired samples, the coefficient of determination (R2), the root-mean-square error (RMSE), the interclass correlation coefficient (ICC), and by graphic analysis of the residuals. A significance value of p <0.05 was adopted. An equation was considered applicable when it had R2 >0.7, the lowest RMSE among the equations evaluated, ICC >0.7, and a confidence interval of 95%, with the smallest difference between the upper and lower limits. A greater mean height was noted among younger elderly persons and elderly men compared to up to 80 years and women elderly. Quantitative analysis revealed that equation for Puerto Ricans, using knee height and age, was the most applicable for the overall population (ICC = 0.802). The same equation was applicable for the elderly Brazilian male participants (ICC = 0.838) and for those aged 60–69 years (ICC = 0.895). None of the equations used were applicable for the height estimation of elderly women or individuals aged 70 years or more.
The aging process increases physical and functional decline, and when combined with institutionalization, it can compromise autonomy and independence. Nutritional status can be affected by physiological alterations and the diseases associated with aging and result in deficits or excesses in indicators. Therefore, the evaluation of nutritional status plays an important role when monitoring situations of nutritional risk.
A cross-sectional, census-based study of elderly residents of nursing homes in Natal city, in the state of Rio Grande do Norte, a city in northeastern Brazil, was carried out between October 2013 and June 2014. The study population consisted of all elderly nursing home residents in this period. The inclusion criteria were nursing home residents aged over 60 years who were present at the time of data collection. The exclusion criteria were individuals confined to bed, for whom it was impossible to properly measure height or who had a physical disability that prevented the taking of anthropometric measurements, such as patients who underwent orthopedic surgery.
Of the total 14 nursing homes in Natal city, 4 refused to participate in the study, of which one was a non-profit organization and the other three were private institutions. Regarding the participants from the nursing homes that participated in the study, nine elderly people refused to participate, and eight were excluded because they did not meet the eligibility criteria; consequently, 168 elderly subjects living in 10 nursing homes participated in the study. The proportion of potencial lost participants was 35.9% of the total number of individuals eligible to participate in the study.
The present census-type study employed a rigorous methodology for the comparison and validation of height estimating equations among elderly persons living in nursing homes. Among the studies that aim to evaluate methods for estimating the height in the elderly, this study was different since several statistical tests and their indices, such as the ICC and the corresponding 95% CI, were used. Meanwhile, most of the studies are restricted to using the Pearson correlations, Student’s t-test for paired samples, or Bland-Altman plot [21–29]. This pioneering concept, however, has led to difficulties in finding studies with a similar objective and methodology to compare the results and discuss them.