Body Mass Index and Its Relationship with Disability, Chronic Diseases and Frailty in Older People: A Comparison of the Lipschitz and Who Classifications.

BACKGROUND: Anthropometric parameters are closely associated with the pathophysiology of frailty and with clinic and functional parameters assessed for its diagnosis. OBJECTIVE: To evaluate the possible association of the nutritional status of older people as assessed by Body Mass Index (BMI) and functional disability, self-reported chronic diseases and frailty, comparing the use of two different classifications of BMI. DESIGN: Cross-sectional study. SETTING: The sample was selected among community-dwelling older people from the city of Ribeirão Preto/ Brazil. PARTICIPANTS: 326 independent older people (mean age 73.8±6.4 years) who participated in the FIBRA (Frailty in Brazilian Older People) study. MEASUREMENTS: Weight and height were collected for BMI analysis and frailty criteria were applied according to Fried et al. Participants were also evaluated for self-reported activities of daily living (Katz Index and Lawton and Brody Scale), and the presence of chronic diseases. RESULTS: The prevalence of frailty was 12.3%. Regardless of the classification of BMI applied, most of the sample was classified as overweight (50.9% and 39.3% in the Lipschitz and WHO classifications, respectively). For both classifications, low weight was the only BMI classification associated with frailty status (OR Lipschitz: 4.12(1.53-11.14); OR WHO: 6.21 (1.26-30.58). Comorbidities and dependence in activities of daily living (ADLs) were associated with BMI ≥ 30kg.m2. CONCLUSION: Regardless of the classification adopted, low weight is associated with frailty. However, when the WHO stratification is employed, high BMI is also associated to increased functional disability and the presence of comorbidities, coexisting factors of frailty.

Gait Speed as a Predictor of Respiratory Muscle Function, Strength, and Frailty Syndrome in Community-Dwelling Elderly People.

BACKGROUND: Gait speed is considered a predictor of adverse health outcomes and functional decline in the elderly. This decline is also identified in respiratory muscles. OBJECTIVE: To assess the impact of gait speed in maximal inspiratory pressure, maximal expiratory pressure, handgrip strength, and the different types of frailty syndrome in community-dwelling elderly people. DESIGN: Cross-sectional study. PARTICIPANTS: Women (aged ≥ 65 years) were classified into different frailty phenotypes (n = 106). MEASUREMENTS: Gait speed (10 m), handgrip strength (Jamar dynamometer), and maximum inspiratory and expiratory pressures (GerAr manovacuometer, MV-150/300 model) were measured. Linear regression analyses were conducted to determine the influence of gait speed and age on handgrip strength, maximal inspiratory pressure, and maximal expiratory pressure. Logistic regression was performed to assess the influence of gait speed and frailty age (α = 0.05). RESULTS: A total of 106 elderly women participated in the study (73.96 ± 6.91 years). Thirty-two subjects were not frail, 42 were pre-frail, and 32 were frail. Gait speed and age significantly predicted handgrip strength and frailty (p < 0.05). In the multivariate model, gait speed had the greatest contribution, while age lost statistical significance. Regarding maximal inspiratory and maximal expiratory pressures, gait speed and age were significant explanatory variables (p < 0.05). In the multivariate model, gait speed lost statistical significance to predict maximal inspiratory pressure. CONCLUSION: Gait speed was confirmed to be a predictor of some health outcomes, including respiratory muscle function. The results suggest that interventions to increase gait speed may contribute to improve respiratory function and muscle strength, and decrease the risk of frailty among elderly people.

Physical therapy intervention (PTI) increases plasma brain-derived neurotrophic factor (BDNF) levels in non-frail and pre-frail elderly women.

Biomarkers are important factors in the identification of the frail elderly (higher risk of developing disease) and in assessing the impact of PTI. On the other hand, BDNF has been related to neuroprotection in a series of central nervous system diseases in older age. The levels of BDNF in groups of elderly women classified according to Fried phenotype (non-frail and pre-frail) were compared. We assessed the impact of a PTI on BDNF levels. A convenience sample of 48 elderly women was randomly selected. The PTI group was composed by 20 elderly women selected from this group. Plasma neurotrophic factors, such as BDNF, glial-derived neutrophic factor (GDNF), and nerve growth factor (NGF) were measured by enzyme-linked immunosorbent assay (ELISA). Timed-up-and-go (TUG) test, hand-grip and work/body weight were evaluated before and after the intervention. Plasma concentrations of BDNF were significantly higher in non-frail in comparison to pre-frail elderly women. After the PTI, higher levels of BDNF were found in elderly women (before 351±68 pg/ml and after 593±79 pg/ml; p<0.001). Both groups had an increase in BDNF levels after the PTI. The low levels of BDNF in pre-frail elderly women suggest that this neurotrophic factor may be a key pathophysiological mediator in the syndrome of frailty. The fact that PTI increased BDNF levels in both groups suggests that it may be possible to modify this phenotype.