Trends in Chiropractic Care and Physical Rehabilitation Use Among Adults with Low Back Pain in the United States, 2002 to 2018.

BACKGROUND: While nonpharmacologic treatments are increasingly endorsed as first-line therapy for low back pain (LBP) in clinical practice guidelines, it is unclear if use of these treatments is increasing or equitable. OBJECTIVE: Examine national trends in chiropractic care and physical rehabilitation (occupational/physical therapy (OT/PT)) use among adults with LBP. DESIGN/SETTING: Serial cross-sectional analysis of the National Health Interview Survey, 2002 to 2018. PARTICIPANTS: 146,087 adults reporting LBP in prior 3 months. METHODS: We evaluated the association of survey year with chiropractic care or OT/PT use in prior 12 months. Logistic regression with multilevel linear splines was used to determine if chiropractic care or OT/PT use increased after the introduction of clinical guidelines. We also examined trends in use by age, sex, race, and ethnicity. When trends were similar over time, we present differences by these demographic characteristics as unadjusted ORs using data from all respondents. RESULTS: Between 2002 and 2018, less than one-third of adults with LBP reported use of either chiropractic care or OT/PT. Rates did not change until 2016 when uptake increased with the introduction of clinical guidelines (2016-2018 vs 2002-2015, OR = 1.15; 95% CI: 1.10-1.19). Trends did not differ significantly by sex, race, or ethnicity (p for interactions > 0.05). Racial and ethnic disparities in chiropractic care or OT/PT use were identified and persisted over time. For example, compared to non-Hispanic adults, either chiropractic care or OT/PT use was lower among Hispanic adults (combined OR = 0.62, 95% CI: 0.65-0.73). By contrast, compared to White adults, Black adults had similar OT/PT use (OR = 0.98; 95% CI: 0.94-1.03) but lower for chiropractic care use (OR = 0.50; 95% CI: 0.47-0.53). CONCLUSIONS: Although use of chiropractic care or OT/PT for LBP increased after the introduction of clinical guidelines in 2016, only about a third of US adults with LBP reported using these services between 2016 and 2018 and disparities in use have not improved.

Physical function in older adults with and without a cancer history: Findings from the National Health and Aging Trends Study.

BACKGROUND: Previous studies identified physical function limitations in older cancer survivors, but few have included objective measures and most focused on breast and prostate cancer survivors. The current study compared patient-reported and objective physical function measures between older adults with and without a cancer history. METHODS: Our cross-sectional study used a nationally representative sample of community-dwelling, Medicare beneficiaries from the 2015 National Health and Aging Trends Study (n = 7495). Data collected included patient-reported physical function, including a composite physical capacity score and limitations in strength, mobility, and balance, and objectively measured physical performance metrics, including gait speed, five time sit-to-stand, tandem stand, and grip strength. All analyses were weighted to account for the complex sampling design. RESULTS: Thirteen percent of participants (n = 829) reported a history of cancer, of which more than half (51%) reported a diagnosis other than breast or prostate cancer. In models adjusted for demographics and health history, older cancer survivors had lower Short Physical Performance Battery scores (unstandardized beta [B] = -0.36; 95% CI: -0.64, -0.08), slower gait speed (B = -0.03; 95% CI: -0.05, -0.01), reduced grip strength (B = -0.86; 95% CI: -1.44, -0.27), worse patient-reported composite physical capacity (B = -0.43; 95% CI: -0.67, -0.18) and patient-reported upper extremity strength (B = 1.27; 95% CI: 1.07, 1.50) compared to older adults without cancer. Additionally, the burden of physical function limitations was greater in women than in men, which may be explained by cancer type. CONCLUSIONS: Our results extend studies in breast and prostate cancer to show worse objective and patient-reported physical function outcomes in older adults with a range of cancer types compared to those without a cancer history. Moreover, these burdens seem to disproportionately affect older adult women, underscoring the need for interventions to address functional limitations and prevent further health consequences of cancer and its treatment.

Trajectories of physical capacity among community-dwelling older adults in the United States.

OBJECTIVE: Although the prognostic value of physical capacity is well-established, less is known about longitudinal patterns of physical capacity among community-dwelling older adults. We sought to describe long-term trajectories of physical capacity in a nationally representative sample of Medicare beneficiaries. DESIGN: Cohort study SETTING AND PARTICIPANTS: Annually collected data on 6,783 community-dwelling participants in the National Health and Aging Trends Study from 2011 to 2016 were analyzed. METHODS: Performance-based physical capacity was measured using the Short Physical Performance Battery [(SPPB) range: 0-12, higher is better]. Self-reported physical capacity was measured using six pairs of activities with composite scores from 0 to 12 (higher is better). We then used group-based trajectory modeling to identify longitudinal patterns of each physical capacity measure over 6 years. Associations of baseline characteristics with trajectories were examined using multinomial logistic regression. RESULTS: The cohort was 57% female, 68% white, and 58% were ≥75 years. Six distinct trajectories of SPPB scores were identified. Two "high" groups (n = 2192, 43%) maintained high average SPPB scores. Two "moderate decline" groups (n = 1459, 29%) had a mid-range SPPB score at baseline and demonstrated gradual decline. A "low decline" group (n = 811, 16%) started with a low SPPB score and experienced a greater decline. A "very low" group (n = 590, 12%) had very low SPPB scores in all years. Six trajectories for self-reported physical capacity were also identified. Older age, worse health, lower income and education, and being Black or Hispanic were associated with lower and declining physical capacity.

Benefit-risk assessment and reporting in clinical trials of chronic pain treatments: IMMPACT recommendations.

ABSTRACT: Chronic pain clinical trials have historically assessed benefit and risk outcomes separately. However, a growing body of research suggests that a composite metric that accounts for benefit and risk in relation to each other can provide valuable insights into the effects of different treatments. Researchers and regulators have developed a variety of benefit-risk composite metrics, although the extent to which these methods apply to randomized clinical trials (RCTs) of chronic pain has not been evaluated in the published literature. This article was motivated by an Initiative on Methods, Measurement, and Pain Assessment in Clinical Trials consensus meeting and is based on the expert opinion of those who attended. In addition, a review of the benefit-risk assessment tools used in published chronic pain RCTs or highlighted by key professional organizations (ie, Cochrane, European Medicines Agency, Outcome Measures in Rheumatology, and U.S. Food and Drug Administration) was completed. Overall, the review found that benefit-risk metrics are not commonly used in RCTs of chronic pain despite the availability of published methods. A primary recommendation is that composite metrics of benefit-risk should be combined at the level of the individual patient, when possible, in addition to the benefit-risk assessment at the treatment group level. Both levels of analysis (individual and group) can provide valuable insights into the relationship between benefits and risks associated with specific treatments across different patient subpopulations. The systematic assessment of benefit-risk in clinical trials has the potential to enhance the clinical meaningfulness of RCT results.

Clinical outcome assessment in clinical trials of chronic pain treatments.

Clinical outcome assessments (COAs) measure outcomes that are meaningful to patients in clinical trials and are critical for determining whether a treatment is effective. The objectives of this study are to (1) describe the different types of COAs and provide an overview of key considerations for evaluating COAs, (2) review COAs and other outcome measures for chronic pain treatments that are recommended by the Initiative on Methods, Measurement, and Pain Assessment in Clinical Trials (IMMPACT) or other expert groups, and (3) review advances in understanding pain-related COAs that are relevant to clinical trials. The authors reviewed relevant articles, chapters, and guidance documents from the European Medicines Agency and U.S. Food and Drug Administration. Since the original core set of outcome measures were recommended by IMMPACT 14 years ago, several new advancements and publications relevant to the measurement or interpretation of COAs for chronic pain trials have emerged, presenting new research opportunities. Despite progress in the quality of measurement of several outcome domains for clinical trials of chronic pain, there remain some measurement challenges that require further methodological investigation.

Longitudinal Patterns of Pain Reporting Among Community-dwelling Older Adults.

OBJECTIVE: The objective of this study was to identify and describe long-term trajectories of bothersome pain and activity-limiting pain in a population-based sample of older adults. MATERIALS AND METHODS: We conducted a retrospective cohort study of 6783 community-dwelling participants using 6 years of longitudinal data from the National Health and Aging Trends Study (NHATS). NHATS is a cohort of older adults that is representative of Medicare Beneficiaries aged 65 years and older. NHATS data collection began in 2011, and demographic and health data are collected annually through in-person interviews. Participants were asked if they had bothersome pain and activity-limiting pain in the past month. We used group-based trajectory modeling to identify longitudinal patterns of bothersome pain and activity-limiting pain over 6 years. We used weighted, multinomial logistic regression to examine associations with each trajectory. RESULTS: The cohort was 57% female, 68% white, and 58% were 75 years and older. Four trajectories were identified for the probability of bothersome pain: persistently high (n=1901, 35%), increasing (n=898, 17%), decreasing (n=917, 17%), and low (n=1735, 32%). Similar trajectories were identified for activity-limiting pain: persistently high (n=721, 13%), increasing (n=812, 15%), decreasing (n=677, 12%), and low (n=3241, 60%). The persistently high bothersome and activity-limiting pain groups had worse health characteristics, were more likely to have fallen in the past year, and had slower gait speed and worse physical capacity compared with the low groups. DISCUSSION: Approximately one half of older adults had a high or increasing probability of long-term bothersome pain, and over one quarter had a high or increasing probability of long-term activity-limiting pain.

An Exploratory Factor Analysis of Sensor-Based Physical Capability Assessment.

Physical capability (PC) is conventionally evaluated through performance-based clinical assessments. We aimed to transform a battery of sensor-based functional tests into a clinically applicable assessment tool. We used Exploratory Factor Analysis (EFA) to uncover the underlying latent structure within sensor-based measures obtained in a population-based study. Three hundred four community-dwelling older adults (163 females, 80.9 ± 6.4 years), underwent three functional tests (Quiet Stand, QS, 7-meter Walk, 7MW and Chair Stand, CST) wearing a smartphone at the lower back. Instrumented tests provided 73 sensor-based measures, out of which EFA identified a fifteen-factor model. A priori knowledge and the associations with health-related measures supported the functional interpretation and construct validity analysis of the factors, and provided the basis for developing a conceptual model of PC. For example, the "Walking Impairment" domain obtained from the 7MW test was significantly associated with measures of leg muscle power, gait speed, and overall lower extremity function. To the best of our knowledge, this is the first time that a battery of functional tests, instrumented through a smartphone, is used for outlining a sensor-based conceptual model, which could be suitable for assessing PC in older adults and tracking its changes over time.

Assessment of physical functioning in the clinical care of the patient with advanced kidney disease.

Maintenance of independent living is the top health priority among patients with advanced chronic kidney disease (CKD). Mobility limitation is often the first sign of functional limitation leading to loss of independence. Regular assessments of physical capacity can help provide kidney health providers identify patients at risk of frailty and other adverse health-related outcomes that contribute to the loss of functional independence. These physical capacities can be measured with commonly used self-reported measures of physical function or by objective physical performance testing. The current review describes commonly used assessments of self-reported physical function and physical performance. First, we describe the disablement process and how these assessments can be performed with commonly used quality of life instruments measuring self-reported physical function or objective physical performance tests. Second, we identify the determinants and correlates of self-reported physical function and physical performance and their contribution to the frailty phenotype. Third, we describe the association of physical capacities with clinical outcomes. We conclude with on possible approach to identifying and intervening on persons with CKD at high risk of functional decline.

Rehabilitation Services Use of Older Adults According to Fall-Risk Screening Guidelines.

OBJECTIVES: To characterize rehabilitation services use of older adults according to fall-risk classification based on screening guidelines. DESIGN: Cross-sectional analysis of 2015 National Health and Aging Trends Study. SETTING: Study participants' homes. PARTICIPANTS: National sample of 7,440 community-dwelling Medicare beneficiaries. MEASUREMENTS: In-person interviews and functional assessments. Based on Centers for Disease Control and Prevention Stopping Elderly Accidents, Deaths and Injuries criteria, participants were classified as low, moderate, or high fall risk. RESULTS: Twenty-three percent of older adults classified as moderate fall-risk (n = 2602) and 40.6% of those at high fall-risk (n = 940) reported rehabilitation services use in the past year. Among older adults who reported rehabilitation services in the past year (n = 1,505), treatment to address falls was reported by 2.8%, 12.6%, and 34.7% of those classified with low, moderate, and high fall-risk, respectively (p < 0.001). Older adults with high fall-risk who did not receive rehabilitation services had significantly better self-reported physical capacity (p = 0.02) but comparable physical performance (all p's > 0.05) relative to those who received rehabilitation. CONCLUSION: Older adults at high risk for falls were significantly more likely to report rehabilitation services use compared to those with low and moderate risk of falling. The findings also indicate that there is low adherence to national clinical recommendations for rehabilitation services use in older adults vulnerable to falls-related injury. Among the high fall-risk group, those who did not receive rehabilitation services had similarly low physical function as compared with those who received rehabilitation, indicating potential unmet need to address physical impairments related to fall-risk. J Am Geriatr Soc 67:100-107, 2019.

Symptom Burden Among Community-Dwelling Older Adults in the United States.

OBJECTIVES: To determine the prevalence and impact of common co-occurring symptoms among community-dwelling older adults in the United States. DESIGN: The National Health and Aging Trends Study is a nationally representative, prospective study with annual data collection between 2011 and 2017. SETTING: Community-based, in-person interviews (survey response rates, 71%-96%). PARTICIPANTS: A total of 7,609 community-dwelling Medicare beneficiaries, 65 years or older. MEASUREMENTS: Symptoms assessed at baseline include pain, fatigue, breathing difficulty, sleeping difficulty, depressed mood, and anxiety. Total symptom count ranged from zero to six. Several outcomes were examined, including grip strength, gait speed, and overall lower-extremity function as well as incidence of recurrent falls (two or more per year), hospitalization, disability, nursing home admission, and mortality. RESULTS: Prevalence of zero, one, two, three, and four or more symptoms was 25.0%, 26.6%, 20.7%, 14.0%, and 13.6%, respectively. Symptom count increased with advancing age and was higher in women than in men. Pain and fatigue were the most common co-occurring symptoms. Higher symptom count was associated with decreased physical capacity. For example, participants with one, two, three, and four or more symptoms had gait speeds that were 0.04, 0.06, 0.09, and 0.13 m/s slower, respectively, than those with no symptoms, adjusting for specific diseases, total number of diseases, and other potential confounders (P < .001). The risk of several adverse outcomes also increased with greater symptom count. For example, compared with those with no symptoms, the adjusted risk ratios for recurrent falls were 1.48 (95% confidence interval [CI] = 1.30-1.70), 1.54 (95% CI = 1.32-1.80), 1.90 (95% CI = 1.55-2.32), and 2.38 (95% CI = 2.00-2.83) for older adults with one, two, three, and four or more symptoms, respectively. CONCLUSIONS: Symptoms frequently co-occur among community-dwelling older adults and are strongly associated with increased risk of a range of adverse outcomes. Symptoms represent a potential treatment target for improving outcomes and should be systematically captured in health records. J Am Geriatr Soc 67:223-231, 2019.

Rehabilitation Services Use and Patient-Reported Outcomes Among Older Adults in the United States.

OBJECTIVE: To characterize rehabilitation service use among community-dwelling older adults in the United States by identifying predictors of rehabilitation utilization, patient-reported functional improvement, and rehabilitation goal attainment. DESIGN: Cross-sectional analysis of the 2015 National Health and Aging Trends Study, which used an age-stratified, multistage sampling design and oversampled blacks and the oldest old (≥85y). SETTING: Standardized, in-person home interviews and physical performance testing. PARTICIPANTS: Nationally representative sample of community-dwelling Medicare beneficiaries (N=7487) aged ≥65 years. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Rehabilitation services use (physical therapy, occupational therapy, and speech therapy) across all settings in the last year, patient-reported functional improvement, and patient-reported rehabilitation goal attainment. RESULTS: Twenty percent of older adults reported rehabilitation use in the last year. In a multivariable model, rehabilitation use was significantly lower among blacks and higher among those with higher education, chronic medical conditions, pain, history of falls, and severe limitations in physical performance. Overall, 72% reported functional improvement during rehabilitation, and 75% reported meeting their goals by discharge. Improved function was associated with longer duration of rehabilitation. A significantly lower percentage of older adults with bothersome pain and severe physical limitations reported meeting rehabilitation goals. CONCLUSIONS: Most older adults who received rehabilitation reported functional improvement and meeting rehabilitation goals. However, social disparities were evident with lower rehabilitation utilization among blacks and those with less education. Importantly, functional improvement and goal attainment did not vary by demographics or diagnoses. Longer duration of rehabilitation and improved pain management may be necessary for functional improvement and goal attainment.

Assessment of Psychosocial and Functional Impact of Chronic Pain.

UNLABELLED: The psychosocial and functional consequences of chronic pain disorders have been well documented as having significant effects on the experience of pain, presentation to health care providers, responsiveness to and participation in treatment, disability, and health-related quality of life. Thus, psychosocial and functional consequences have been incorporated as 1 of the 5 dimensions within the integrated Analgesic, Anesthetic, and Addiction Clinical Trial Translations, Innovations, Opportunities, and Networks (ACTTION)-American Pain Society (APS) Pain Taxonomy (AAPT): 1) core diagnostic criteria; 2) common features; 3) common medical comorbidities; 4) neurobiological, psychosocial, and functional consequences; and 5) putative neurobiological and psychosocial mechanisms, risk factors, and protective factors. In this article we review the rationale for a biopsychosocial perspective, on the basis of current evidence, and describe a set of key psychosocial and behavioral factors (eg, mood/affect, coping resources, expectations, sleep quality, physical function, and pain-related interference with daily activities) that are important consequences of persistent pain and that should be considered when classifying patients within the comprehensive AAPT chronic pain structure. We include an overview of measures and procedures that have been developed to assess this set of factors and that can be used as part of the comprehensive assessment and classification of pain and to address specific research questions. PERSPECTIVE: Psychosocial and functional consequences are important considerations in the classification of individuals with chronic pain. A set of key psychosocial and behavioral factors (eg, mood/affect, coping resources, expectations, sleep quality, physical function, and pain-related interference with daily activities) that should be considered when classifying patients within the comprehensive classification of chronic pain disorders developed by the AAPT are outlined and examples of assessment methods for each are described.

Assessment of physical function and participation in chronic pain clinical trials: IMMPACT/OMERACT recommendations.

Although pain reduction is commonly the primary outcome in chronic pain clinical trials, physical functioning is also important. A challenge in designing chronic pain trials to determine efficacy and effectiveness of therapies is obtaining appropriate information about the impact of an intervention on physical function. The Initiative on Methods, Measurement, and Pain Assessment in Clinical Trials (IMMPACT) and Outcome Measures in Rheumatology (OMERACT) convened a meeting to consider assessment of physical functioning and participation in research on chronic pain. The primary purpose of this article is to synthesize evidence on the scope of physical functioning to inform work on refining physical function outcome measurement. We address issues in assessing this broad construct and provide examples of frequently used measures of relevant concepts. Investigators can assess physical functioning using patient-reported outcome (PRO), performance-based, and objective measures of activity. This article aims to provide support for the use of these measures, covering broad aspects of functioning, including work participation, social participation, and caregiver burden, which researchers should consider when designing chronic pain clinical trials. Investigators should consider the inclusion of both PROs and performance-based measures as they provide different but also important complementary information. The development and use of reliable and valid PROs and performance-based measures of physical functioning may expedite development of treatments, and standardization of these measures has the potential to facilitate comparison across studies. We provide recommendations regarding important domains to stimulate research to develop tools that are more robust, address consistency and standardization, and engage patients early in tool development.

Is there a sex difference in accelerometer counts during walking in older adults?

BACKGROUND: Accelerometers have emerged as a useful tool for measuring free-living physical activity in epidemiological studies. Validity of activity estimates depends on the assumption that measurements are equivalent for males and females while performing activities of the same intensity. The primary purpose of this study was to compare accelerometer count values in males and females undergoing a standardized 6-minute walk test. METHODS: The study population was older adults (78.6 ± 4.1 years) from the AGES-Reykjavik Study (N = 319). Participants performed a 6-minute walk test at a self-selected fast pace while wearing an ActiGraph GT3X at the hip. Vertical axis counts · s(-1) was the primary outcome. Covariates included walking speed, height, weight, BMI, waist circumference, femur length, and step length. RESULTS: On average, males walked 7.2% faster than females (1.31 vs. 1.22 m · s(-1), P < .001) and had 32.3% greater vertical axis counts · s(-1) (54.6 vs. 39.4 counts · s(-1), P < .001). Accounting for walking speed reduced the sex difference to 19.2% and accounting for step length further reduced the difference to 13.4% (P < .001). CONCLUSION: Vertical axis counts · s(-1) were disproportionally greater in males even after adjustment for walking speed. This difference could confound free-living activity estimates.

Subclinical vascular disease burden and risk for death and cardiovascular events in older community dwellers.

BACKGROUND: Individual measures and previous composite measures of subclinical vascular disease defined high risk for cardiovascular events, but did not detect low and modest risk. A different approach might better describe the spectrum from low to high risk. Methods and Results. In the Cardiovascular Health Study, 3,252 participants without history of clinical cardiovascular disease (M ± SD 74.3 years ± 5.1, 63% women, 17% African Americans) had noninvasive vascular assessments in 1992-1993. We assigned a score of 0, 1, or 2 (no, mild, or severe abnormalities) to ankle-arm index, electrocardiogram, and common carotid intima-media thickness, based on clinical cutoffs. A summary index (range 0-6, absent to severe disease) summed individual scores. Abdominal aortic ultrasound and brain magnetic resonance imaging were collected in a subsample. Mortality and incident cardiovascular events were identified through June 2008. Event and death rates increased across index grades. Comparing grades 1 to 5+ with absent disease, and adjusting for demographics, hazard ratios for cardiovascular events within 8 years ranged from 1.1 (95% confidence interval 0.8-1.6) to 4.7 (3.4-6.9) and, for mortality, from 1.5 (1.0-2.3) to 5.0 (3.3-7.7) (p for trend across grades <.001 for both outcomes). Adjustment for cardiovascular risk factors did not substantially change the associations. The index improved mortality risk classification over demographics and risk factors in participants who did not die during the follow-up. Including in the index the aortic ultrasound and the brain magnetic resonance imaging further improved risk classification. CONCLUSIONS: Older adults with minimal subclinical vascular disease had low cardiovascular events risk and mortality. This approach might more fully account for vascular burden.

Activity energy expenditure and mobility limitation in older adults: differential associations by sex.

In this study, the authors aimed to determine whether higher activity energy expenditure, assessed by using doubly labeled water, was associated with a reduced decline in mobility limitation among 248 older community-dwelling US adults aged 70-82 years enrolled in 1998-1999. Activity energy expenditure was calculated as total energy expenditure (assessed over 2 weeks by using doubly labeled water) minus resting metabolic rate (measured with indirect calorimetry), with adjustment for the thermic effect of food. Across sex-specific tertiles of activity energy expenditure, men in the lowest activity group experienced twice the rate of mobility limitation as men in the highest activity group (41% (n = 18) vs. 18% (n = 8)). Conversely, women in the lowest and highest activity groups exhibited similarly high rates of mobility limitation (40% (n = 16) vs. 38% (n = 15)). After adjustment for potential confounders, men with higher activity energy expenditure levels continued to show reduced risk of mobility limitation (per standard deviation (284 kcal/day): hazard ratio = 0.61, 95% confidence interval: 0.41, 0.92). Women showed no association (per standard deviation (226 kcal/day): hazard ratio = 1.34, 95% confidence interval: 0.98, 1.85). Greater energy expenditure from any and all physical activity was significantly associated with reduced risk of developing mobility limitation among men, but not among women.

Daily activity energy expenditure and mortality among older adults.

CONTEXT: Exercise is associated with mortality benefits but simply expending energy through any activity in an individual's free-living environment may confer survival advantages. OBJECTIVE: To determine whether free-living activity energy expenditure is associated with all-cause mortality among older adults. DESIGN, SETTING, AND PARTICIPANTS: Free-living activity energy expenditure was assessed in 302 high-functioning, community-dwelling older adults (aged 70-82 years). Total energy expenditure was assessed over 2 weeks using doubly labeled water. Resting metabolic rate was measured using indirect calorimetry and the thermic effect of meals was estimated at 10% of total energy expenditure. Free-living activity energy expenditure was calculated as: (total energy expenditure x 0.90) - resting metabolic rate. Participants were followed up over a mean of 6.15 years (1998-2006). MAIN OUTCOME MEASURES: Free-living activity energy expenditure (3 tertiles: low, <521 kcal/d; middle, 521-770 kcal/d; high, >770 kcal/d) and all-cause mortality. RESULTS: Fifty-five participants (18.2%) died during follow-up. As a continuous risk factor, an SD increase in free-living activity energy expenditure (287 kcal/d) was associated with a 32% lower risk of mortality after adjusting for age, sex, race, study site, weight, height, percentage of body fat, and sleep duration (hazard ratio, 0.68; 95% confidence interval, 0.48-0.96). Using the same adjustments, individuals in the highest tertile of free-living activity energy expenditure were at a significantly lower mortality risk compared with the lowest tertile (hazard ratio, 0.31; 95% confidence interval, 0.14-0.69). Absolute risk of death was 12.1% in the highest tertile of activity energy expenditure vs 24.7% in the lowest tertile; absolute risks were similar to these for tertiles of physical activity level. The effect of free-living activity energy expenditure changed little after further adjustment for self-rated health, education, prevalent health conditions, and smoking behavior. According to self-reports, individuals expending higher levels of free-living activity energy were more likely to work for pay (P = .004) and climb stairs (P = .01) but self-reported high-intensity exercise, walking for exercise, walking other than for exercise, volunteering, and caregiving did not differ significantly across the activity energy expenditure tertiles. CONCLUSIONS: Objectively measured free-living activity energy expenditure was strongly associated with lower risk of mortality in healthy older adults. Simply expending energy through any activity may influence survival in older adults.

Expanding the disablement process model among older Mexican Americans.

BACKGROUND: Very few studies have examined how disability develops among older Mexican Americans. To determine how disability develops, we explored the Disablement Process model, which posits that impairment, measured by muscle strength, leads to functional limitations, which lead to disability, which ultimately is associated with health-related quality of life (HRQOL). METHODS: A structural equation model approach was used (AMOS 4) with data collected on 622 Mexican Americans aged 71 or older residing in the Southwest. RESULTS: Our results show preliminary support for the Disablement Process model. Impairment is significantly associated with functional limitation (beta =.36, z value = 7.2), which is significantly associated with disability (beta = -.53, z value = 16.1). Finally, disability is significantly related to both physical and mental components of HRQOL (beta = -.69, z value = 23.4; beta = -.26, z value = 6.5, respectively). CONCLUSIONS: Muscle strength as a measure of impairment and the Medical Outcomes Study 36-Item Short-Form Health Survey (SF-36) score as a measure of HRQOL are important factors in understanding disability in older Mexican Americans.

Neighborhood context and mortality among older Mexican Americans: is there a barrio advantage?

OBJECTIVES: We examined whether Mexican Americans living in high-density Mexican American neighborhoods experience increased morbidity and mortality compared with the rates observed among Mexican Americans living in low-density areas. METHODS: We conducted a prospective analysis of a cohort of 3050 Mexican Americans aged 65 years or older. We examined prevalence of 6 medical conditions and survival over 7 years of follow-up in relation to percentage of Mexican Americans in the census tract. RESULTS: With adjustment for covariates, odds for disease prevalence among older Mexican Americans as a function of percentage of Mexican Americans in the census tract were 0.33 (95% confidence interval [CI]=0.16, 0.71) for stroke, 0.28 (95% CI= 0.11, 0.70) for cancer, and 0.31 (95% CI=0.10, 0.98) for hip fracture. The hazard ratio for all-cause mortality over 7 years' follow-up was 0.64 (95% CI=0.42, 0.96). CONCLUSIONS: Sociocultural advantages conferred on Mexican Americans by living in high-density Mexican American neighborhoods outweigh the disadvantages conferred by the high poverty of those neighborhoods.

Neighborhood context and self-rated health in older Mexican Americans.

PURPOSE: To determine whether neighborhood characteristics are associated with self-rated health in older Mexican Americans. METHODS: Epidemiologic data on 3050 older Mexican Americans residing in the southwestern United States during 1993 and 1994 were merged with 1990 US Census data. All subjects were matched to one of 210 census tracts (neighborhoods). Multilevel ordinal logit models were used to examine relationships between self-rated health and individual- and neighborhood-level variables. RESULTS: After adjusting for individual characteristics, older Mexican Americans were more likely to rate their health poorer if they lived in neighborhoods that were economically disadvantaged, less populated by other Hispanics, or located within 50 miles of the US-Mexico border. In addition, residence in a border community moderated the relationship between self-rated health and neighborhood economic disadvantage. The effect of neighborhood economic disadvantage on poorer self-rated health was two to three times stronger for subjects living near the border region than subjects living further away from the border. CONCLUSIONS: This study demonstrates the importance of considering several dimensions of neighborhood context, especially for Mexican Americans. Residence in a border community and neighborhood economic disadvantage were important predictors of poorer self-rated health status. In addition, older Mexican Americans experience a health benefit from living in neighborhoods populated with other Hispanics.