The Instrumented Stand and Walk (ISAW) test to predict falls in older men.

Objective measures of balance and gait have the potential to improve prediction of future fallers because balance and gait impairments are common precursors. We used the Instrumented Stand and Walk Test (ISAW) with wearable, inertial sensors to maximize the domains of balance and gait evaluated in a short test. We hypothesized that ISAW objective measures across a variety of gait and balance domains would improve fall prediction beyond history of falls and better than gait speed or dual-task cost on gait-speed. We recruited 214 high-functioning older men (mean 82 years), of whom 91 participants (42.5%) had one or more falls in the 12 months following the ISAW test. The ISAW test involved 30 s of stance followed by a 7-m walk, turn, and return. We examined regression models for falling using 17 ISAW metrics, with and without age and fall history, and characterize top-performing models by AUC and metrics included. The ISAW test improved distinguishing between future fallers and non-fallers compared to age and history of falls, alone (AUC improved from 0.69 to 0.75). Models with 1 ISAW metric usually included a postural sway measure, models with 2 ISAW measures included a turning measure, models with 3 ISAW measures included a gait variability measure, and models with 4 or 5 measures added a gait initiation measure. Gait speed and dual-task cost did not distinguish between fallers and non-fallers in this high-functioning cohort. The best fall-prediction models support the notion that older people may fall due to a variety of balance and gait impairments.

Successful collection of stool samples for microbiome analyses from a large community-based population of elderly men.

The relationship of the gastrointestinal microbiome to health and disease is of major research interest, including the effects of the gut microbiota on age related conditions. Here we report on the outcome of a project to collect stool samples on a large number of community dwelling elderly men using the OMNIgene-GUT stool/feces collection kit (OMR-200, DNA Genotek, Ottawa, Canada). Among 1,328 men who were eligible for stool collection, 982 (74%) agreed to participate and 951 submitted samples. The collection process was reported to be acceptable, almost all samples obtained were adequate, the process of sample handling by mail was uniformly successful. The DNA obtained provided excellent results in microbiome analyses, yielding an abundance of species and a diversity of taxa as would be predicted. Our results suggest that population studies of older participants involving remote stool sample collection are feasible. These approaches would allow large scale research projects of the association of the gut microbiota with important clinical outcomes.

Obesity and Falls in a Prospective Study of Older Men: The Osteoporotic Fractures in Men Study.

OBJECTIVE: The aim of this study is to evaluate fall rates across body mass index (BMI) categories by age group, considering physical performance and comorbidities. METHOD: In the Osteoporotic Fractures in Men (MrOS) study, 5,834 men aged ≥65 reported falls every 4 months over 4.8 (±0.8) years. Adjusted associations between BMI and an incident fall were tested using mixed-effects models. RESULTS: The fall rate (0.66/man-year overall, 95% confidence interval [CI] = [0.65, 0.67]) was lowest in the youngest, normal weight men (0.44/man-year, 95% CI = [0.41, 0.47]) and greatest in the oldest, highest BMI men (1.47 falls/man-year, 95% CI = [1.22, 1.76]). Obesity was associated with a 24% to 92% increased fall risk in men below 80 ( ptrend ≤ .0001, p for interaction by age = .03). Only adjustment for dynamic balance test altered the BMI-falls association substantially. DISCUSSION: Obesity was independently associated with higher fall rates in men 65 to 80 years old. Narrow walk time, a measure of gait stability, may mediate the association.