Yvonne L. Michael

Frailty in Older Men: Prevalence, Progression, and Relationship with Mortality

OBJECTIVES: To describe the association between frailty and health status, the progression of frailty, and the relationship between frailty and mortality in older men.

The Relation between Neighborhood Built Environment and Walking Activity among Older Adults

The association of neighborhood built environment with walking activity has received growing attention, although most studies have relied upon subjective measures of the built environment and few have examined the relation between built environment and walking among older adults. This 2001 study examined the relation between objectively measured characteristics of the local neighborhood and walking activity among a sample of 546 community-dwelling older adults in Portland, Oregon. A geographic information system was used to derive measures of the built environment within a quarter-mile (0.4 km) and half-mile (0.8 km) radius around each participants residence. Multilevel regression analysis was used to examine the association of built environment with walking behavior. No association between built environment and the likelihood of walking or not walking was observed in this cohort of older adults. However, among those participants who reported some degree of walking activity, average time spent walking per week was significantly associated with amount of automobile traffic and number of commercial establishments in their local neighborhood. These findings suggest that built environment may not play a significant role in whether older adults walk, but, among those who do walk, it is associated with increased levels of activity.

Primary Care-Relevant Interventions to Prevent Falling in Older Adults: A Systematic Evidence Review for the U.S. Preventive Services Task Force

BACKGROUND Falls among older adults are both prevalent and preventable. PURPOSE To describe the benefits and harms of interventions that could be used by primary care practitioners to prevent falling among community-dwelling older adults. DATA SOURCES The reviewers evaluated trials from a good-quality systematic review published in 2003 and searched MEDLINE, the Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, and CINAHL from the end of that reviews search date to February 2010 to identify additional English-language trials. STUDY SELECTION Two reviewers independently screened 3423 abstracts and 638 articles to identify randomized, controlled trials (RCTs) of primary care-relevant interventions among community-dwelling older adults that reported falls or fallers as an outcome. Trials were independently critically appraised to include only good- or fair-quality trials; discrepancies were resolved by a third reviewer. DATA EXTRACTION One reviewer abstracted data from 61 articles into standardized evidence tables that were verified by a second reviewer. DATA SYNTHESIS Overall, the included evidence was of fair quality. In 16 RCTs evaluating exercise or physical therapy, interventions reduced falling (risk ratio, 0.87 [95% CI, 0.81 to 0.94]). In 9 RCTs of vitamin D supplementation, interventions reduced falling (risk ratio, 0.83 [CI, 0.77 to 0.89]). In 19 trials involving multifactorial assessment and management, interventions with comprehensive management seemed to reduce falling, although overall pooled estimates were not statistically significant (risk ratio, 0.94 [CI, 0.87 to 1.02]). Limited evidence suggested that serious clinical harms were no more common for older adults in intervention groups than for those in control groups. LIMITATIONS Interventions and methods of fall ascertainment were heterogeneous. Data on potential harms of interventions were scant and often not reported. CONCLUSION Primary care-relevant interventions exist that can reduce falling among community-dwelling older adults. PRIMARY FUNDING SOURCE Agency for Healthcare Research and Quality.

Protein intake and incident frailty in the Women's Health Initiative observational study.

OBJECTIVES: To evaluate the association between protein intake and incident frailty.

The Urban Built Environment and Mobility in Older Adults: A Comprehensive Review

Mobility restrictions in older adults are common and increase the likelihood of negative health outcomes and premature mortality. The effect of built environment on mobility in older populations, among whom environmental effects may be strongest, is the focus of a growing body of the literature. We reviewed recent research (1990–2010) that examined associations of objective measures of the built environment with mobility and disability in adults aged 60 years or older. Seventeen empirical articles were identified. The existing literature suggests that mobility is associated with higher street connectivity leading to shorter pedestrian distances, street and traffic conditions such as safety measures, and proximity to destinations such as retail establishments, parks, and green spaces. Existing research is limited by differences in exposure and outcome assessments and use of cross-sectional study designs. This research could lead to policy interventions that allow older adults to live more healthy and active lives in their communities.

The Relationship Between Trees and Human Health: Evidence from the Spread of the Emerald Ash Borer

BACKGROUND Several recent studies have identified a relationship between the natural environment and improved health outcomes. However, for practical reasons, most have been observational, cross-sectional studies. PURPOSE A natural experiment, which provides stronger evidence of causality, was used to test whether a major change to the natural environment-the loss of 100 million trees to the emerald ash borer, an invasive forest pest-has influenced mortality related to cardiovascular and lower-respiratory diseases. METHODS Two fixed-effects regression models were used to estimate the relationship between emerald ash borer presence and county-level mortality from 1990 to 2007 in 15 U.S. states, while controlling for a wide range of demographic covariates. Data were collected from 1990 to 2007, and the analyses were conducted in 2011 and 2012. RESULTS There was an increase in mortality related to cardiovascular and lower-respiratory-tract illness in counties infested with the emerald ash borer. The magnitude of this effect was greater as infestation progressed and in counties with above-average median household income. Across the 15 states in the study area, the borer was associated with an additional 6113 deaths related to illness of the lower respiratory system, and 15,080 cardiovascular-related deaths. CONCLUSIONS Results suggest that loss of trees to the emerald ash borer increased mortality related to cardiovascular and lower-respiratory-tract illness. This finding adds to the growing evidence that the natural environment provides major public health benefits.

Health behaviors, social networks, and healthy aging: Cross-sectional evidence from the Nurses' Health Study

Physical function is a significant component of health-related quality of life among older adults. Potential correlates of healthy aging, including health behaviors and social network characteristics, were examined among 56,436 US women aged 55–72 in 1992. Healthy aging was assessed by maintenance of physical function measured by four sub-scales of the Medical Outcomes Study Short Form (SF)-36 Health Survey: physical functioning; role limitations; freedom from bodily pain; and vitality. Individual health behaviors, defined as current smoking, alcohol consumption, sedentary behavior, and being overweight each contributed to significant decrements in functioning across all age-groups. After controlling for these health behaviors and other confounders (age, race, education, and co-morbid conditions), elements of a womans social network were significantly correlated with functional status. Strong predictors of high functioning among older women were having close friends and relatives and presence of a confidant. For example, the absence of a confidant was associated with a 4.44 point reduction in physical functioning (95% CI: −7.0, −1.9), and a 5.68 point reduction in vitality (95% CI: −7.9, −3.4). These effects were comparable in magnitude to those observed among heavy smokers, or women in the highest category of body mass index.

Urban trees and the risk of poor birth outcomes

This paper investigated whether greater tree-canopy cover is associated with reduced risk of poor birth outcomes in Portland, Oregon. Residential addresses were geocoded and linked to classified-aerial imagery to calculate tree-canopy cover in 50, 100, and 200 m buffers around each home in our sample (n=5696). Detailed data on maternal characteristics and additional neighborhood variables were obtained from birth certificates and tax records. We found that a 10% increase in tree-canopy cover within 50 m of a house reduced the number of small for gestational age births by 1.42 per 1000 births (95% CI-0.11-2.72). Results suggest that the natural environment may affect pregnancy outcomes and should be evaluated in future research.

Building on Leadership and Social Capital to Create Change in 2 Urban Communities

There has been an appeal to reduce health inequities by increasing community involvement and social capital. Poder es Salud/Power for Health is a community-based participatory prevention research project that seeks to address health disparities in the African American and Latino communities by enhancing community-level social capital. We provide specific examples of how this intervention uses community health workers and popular education to reduce language and cultural barriers and enhance community social capital. Although the communities share fundamental challenges related to health disparities, the ways in which the Latino and African American communities identify health concerns, create solutions, and think about social capital vary. Members of the project are working together to identify opportunities for cross-cultural collaboration.

The Women's Health Initiative: The food environment, neighborhood socioeconomic status, BMI, and blood pressure.

Using data (n = 60,775 women) from the Womens Health Initiative Clinical Trial (WHI CT)—a national study of postmenopausal women aged 50–79 years—we analyzed cross‐sectional associations between the availability of different types of food outlets in the 1.5 miles surrounding a womans residence, census tract neighborhood socioeconomic status (NSES), BMI, and blood pressure (BP). We simultaneously modeled NSES and food outlets using linear and logistic regression models, adjusting for multiple sociodemographic factors, population density and random effects at the tract and metropolitan statistical area (MSA) level. We found significant associations between NSES, availability of food outlets and individual‐level measurements of BMI and BP. As grocery store/supermarket availability increased from the 10th to the 90th percentile of its distribution, controlling for confounders, BMI was lower by 0.30 kg/m2. Conversely, as fast‐food outlet availability increased from the 10th to the 90th percentile, BMI was higher by 0.28 kg/m2. When NSES increased from the 10th to the 90th percentile of its distribution, BMI was lower by 1.26 kg/m2. As NSES increased from the 10th to the 90th percentile, systolic and diastolic BP were lower by 1.11 mm Hg and 0.40 mm Hg, respectively. As grocery store/supermarket outlet availability increased from the 10th and 90th percentiles, diastolic BP was lower by 0.31 mm Hg. In this national sample of postmenopausal women, we found important independent associations between the food and socioeconomic environments and BMI and BP. These findings suggest that changes in the neighborhood environment may contribute to efforts to control obesity and hypertension.