Which Neuromuscular Attributes Are Most Associated With Mobility Among Older Primary Care Patients?

Objective

To identify the neuromuscular attributes that are associated with self-reported mobility status among older primary care patients.

Design

Cohort study.

Setting

Metropolitan-based health care system.

Participants

Community-dwelling primary care patients aged ≥65 years (N=430), with self-reported modification of mobility tasks resulting from underlying health conditions.

Interventions

Not applicable.

Main Outcome Measures

Basic and Advanced Lower Extremity Function as measured by the Late Life Function and Disability Instrument.

Results

We constructed multivariable linear regression models evaluating both outcomes. For Basic Lower Extremity Function, leg strength, leg velocity, trunk extensor muscle endurance, and ankle range of motion (ROM) were statistically significant predictors (P<.001, R²=.21). For Advanced Lower Extremity Function, leg strength, leg strength asymmetry, leg velocity, trunk extensor muscle endurance, and knee flexion ROM were statistically significant predictors (P<.001, R²=.39). Sensitivity analyses conducted using multiple imputations to account for missing data confirmed these findings.

Conclusions

This analysis highlights the relevance and importance of 5 categories of neuromuscular attributes: strength, speed of movement, ROM, asymmetry, and trunk stability. It identifies novel attributes (leg velocity and trunk extensor muscle endurance) relevant to mobility and highlights that impairment profiles vary by the level of mobility assessed. These findings will inform the design of more thorough and potentially more effective disability prevention strategies.     

Community Ambulation in Older Adults: Which Internal Characteristics Are Important?

Lord SE, Weatherall M, Rochester L. Community ambulation in older adults: which internal characteristics are important?

Objective

To examine the internal characteristics of older adults independent in community ambulation to gain further understanding of the skills required for its successful execution.

Design

Exploratory factor analysis.

Setting

General community.

Participants

Healthy, community dwelling older adults (N=113) who were cognitively intact and walked outdoors independently.

Interventions

Not applicable.

Main Outcome Measures

Spatiotemporal gait parameters derived from accelerometry over 6 minutes walking outdoors and a battery of measures for motor, cognitive, executive, and behavioral characteristics.

Results

Mean participant age ± SD was 75.8±7.3 years, with almost a third of the sample over 80 years. Four factors emerged from the Factor Analysis of 23 variables: motor control, self-efficacy, executive function, and cognitive-motor interference, which together explained 61.4% of common variance. Eight variables loaded onto motor control, accounting for 34.5% of common variance; 7 items loaded onto self-efficacy, which explained 12.4% of common variance; 5 variables loaded onto executive function, accounting for 8.4% of common variance; and 3 variables loaded onto cognitive-motor interference, explaining 6% of the variance.

Conclusions

Results of this study indicate that factors beyond motor control contribute to independent community ambulation in older adults, reflecting the multidimensional, complex nature of the task. Self-efficacy was shown to be more relevant than executive function to gait performance, suggesting the need for a broader approach to assessment and intervention strategies.     

What Are the Relations Between Voluntary Postural Sway Measures and Falls-History Status in Community-Dwelling Older Adults?

Tucker MG, Kavanagh JJ, Morrison S, Barrett RS. What are the relations between voluntary postural sway measures and falls-history status in community-dwelling older adults?

Objectives

To determine whether a series of voluntary postural sway tasks could differentiate and accurately identify the falls-history status of older adults, and to examine the relations between voluntary sway measures and falls risk.

Design

Case-control study.

Setting

University biomechanics laboratory.

Participants

Healthy community-dwelling older adults (N=51) aged 65 to 94 years who were divided into nonfaller (n=36), single faller (n=10), and multiple faller (n=5) groups based on a 12-month history of falls.

Interventions

Not applicable.

Main Outcome Measures

Participants underwent a falls-risk assessment using the Physiological Profile Assessment (PPA) and then performed 6 voluntary postural sway tasks. The tasks included maximum static leans, maximum voluntary sway, continuous voluntary sway, rapid initiation of voluntary sway, rapid termination of voluntary sway, and rapid orthogonal switches of voluntary sway between the anterior-posterior and medial-lateral directions. Center of pressure amplitudes and reaction time measures were examined using analysis of covariance, Pearson's correlation, and discriminant function analyses.

Results

Multiple fallers had increased age; increased falls risk; slower initiation, termination, and orthogonal switch reaction times; and reduced center of pressure amplitude during sway initiation and continuous voluntary sway compared with nonfallers. Few differences were observed between the nonfallers and single fallers. Voluntary sway measures were significantly correlated with each other and with PPA score. Two postural reaction time measures and age identified 80% of multiple fallers and 98% of nonmultiple fallers. Similarly, PPA score and age identified 80% of multiple fallers and 100% of nonmultiple fallers.

Conclusions

The slower and less effective balance responses of multiple fallers compared with nonfallers and the comparable sensitivity and specificity of PPA score and reactive voluntary sway measures indicate that postural reaction time is a strong determinant of falls risk.     

“Age-Related Positivity Effect” in the Relationship Between Pain and Depression Among Chinese Community-Dwelling Older Adults: Sex Differences

PurposeTo examine the “age-related positivity effect” and its sex differences in the pain-depression relationship among Chinese community-dwelling older adults.DesignCross-sectional design.MethodsThe study was conducted with a sample of 1,913 older adults in Jinan, China. Data were collected on pain intensity, age, sex, depressive symptoms, and potential covariates.ResultsThe hierarchical linear regression analyses revealed that pain intensity was significantly related to depressive symptoms, there was a significant two-way interaction between age and pain intensity, and there was a significant three-way interaction between sex, age, and pain intensity. The Johnson-Neyman plot revealed that the relationship between pain and depressive symptoms decreased with advancing age, indicating an “age-related positivity effect.” And the age-related positivity effect in the pain-depression relationship was significant only in men, but not in women.ConclusionsThe study suggests that all older women and “young-old” men (younger senior citizens aged 60-79) in China are more likely to experience depressive symptoms from pain. Interventions on cognitive psychology should particularly target all older women and young-old men to reduce the detrimental effect of pain on emotional well-being.     

Remission From Suicidal Ideation Among Those in Chronic Pain: What Factors Are Associated With Resilience?

Although there have been many studies on the link between chronic pain and suicidality, surprisingly little research has focused on resilience and recovery among those in chronic and disabling pain who have had suicidal thoughts. The objectives of this study were to identify the prevalence and correlates of recovery from suicidal thoughts among those in chronic pain. A secondary analysis of a nationally representative sample of Canadians in chronic and disabling pain who had ever had serious suicidal thoughts (N = 635) was conducted to identify the prevalence and characteristics of those who are no longer considering suicide. Data were drawn from the Canadian Community Health Survey-Mental Health. Three in five Canadians in chronic pain (63%) who had seriously considered suicide at some point in their life had been free of these thoughts in the past year. Those free of suicidal ideation were significantly more likely to be older, women, white, better educated, with a confidant, and to use spirituality to cope, but less likely to have low household incomes, difficulties meeting basic expenses, and a history of depression and anxiety disorders.PerspectiveAlmost two-thirds of formerly suicidal Canadians with chronic pain were free from suicidal thoughts in the past year. These findings provide a hopeful message of resilience and recovery in the context of disabling pain and help to improve targeted outreach to those most at risk for unremitting suicidality.     

Memory Performance and Affect: Are there Gender Differences in Community-Residing Older Adults?

After age 65, the incidence of episodic memory decline in males is greater than in females. We explored the influence of anxiety and depression on objective and subjective memory performance in a diverse sample of community-residing older adults. The study was a secondary analysis of data on three samples of adults from two states, Ohio and Texas: a community sample (n = 177); a retirement community sample (n = 97); and the SeniorWISE Study (n = 265). The sample of 529 adults was 74% female, the average age was 76.58 years (range = 59–100 years), and educational attainment was 13.12 years (±3.68); 68% were Caucasian, and 17% had depressive symptoms. We found no memory performance differences by gender. Males and females were similarly classified into the four memory performance groups, with almost half of each gender in the poor memory category. Even though males had greater years of education, they used fewer compensatory memory strategies. The observed gender differences in memory were subjective evaluations, specifically metamemory. Age was not a significant predictor of cognition or memory performance, nor did males have greater memory impairment than females.     

Is Highly Challenging and Progressive Balance Training Feasible in Older Adults With Parkinson's Disease?

Objective

To develop a highly challenging and progressive group balance training regime specific to Parkinson's disease (PD) symptoms and to investigate its feasibility in older adults with mild to moderate PD.

Design

Intervention study, before-after trial with a development and feasibility design.

Setting

University hospital setting.

Participants

Feasibility was evaluated in older adults (N=5; mean age, 72y; age range, 69–80y) with mild to moderate idiopathic PD.

Intervention

A balance training regime emphasizing specific and highly challenging exercises, performed 3 times per week for 12 weeks, was developed through discussion and workshops by a group of researchers and physiotherapists.

Main Outcome Measures

Indicators of feasibility included attendance rate, safety (adverse events, physical function, and pain), participants' perceptions of the intervention (level of difficulty of the exercises, motivation level, and appreciation), and efficacy of the intervention (balance performance assessed with the Mini-Balance Evaluation Systems Test [Mini-BESTest]).

Results

The incidence rate was high (93%) for attendance and low (1.2%) for adverse events. Ratings by the participants indicated progression throughout the training period. All participants considered the training motivational and stated that they would recommend it to others. The efficacy of the intervention measured with the Mini-BESTest showed that 4 out of 5 participants improved their balance performance.

Conclusions

These findings support the overall feasibility of this novel balance program in older adults with mild to moderate PD. However, to further evaluate the efficacy of the program, a larger randomized controlled trial is required.     

Elevated HbA1c and Fasting Plasma Glucose in Predicting Diabetes Incidence Among Older Adults: Are two better than one?

OBJECTIVE

To determine which measures—impaired fasting glucose (IFG), elevated HbA_1c, or both—best predict incident diabetes in older adults.

RESEARCH DESIGN AND METHODS

From the Health, Aging, and Body Composition study, we selected individuals without diabetes, and we defined IFG (100–125 mg/dL) and elevated HbA_1c (5.7–6.4%) per American Diabetes Association guidelines. Incident diabetes was based on self-report, use of antihyperglycemic medicines, or HbA_1c ≥6.5% during 7 years of follow-up. Logistic regression analyses were adjusted for age, sex, race, site, BMI, smoking, blood pressure, and physical activity. Discrimination and calibration were assessed for models with IFG and with both IFG and elevated HbA_1c.

RESULTS

Among 1,690 adults (mean age 76.5, 46% men, 32% black), 183 (10.8%) developed diabetes over 7 years. Adjusted odds ratios of diabetes were 6.2 (95% CI 4.4–8.8) in those with IFG (versus those with fasting plasma glucose [FPG] <100 mg/dL) and 11.3 (7.8–16.4) in those with elevated HbA_1c (versus those with HbA_1c <5.7%). When FPG and HbA_1c were considered together, odds ratios were 3.5 (1.9–6.3) in those with IFG only, 8.0 (4.8–13.2) in those with elevated HbA_1c only, and 26.2 (16.3–42.1) in those with both IFG and elevated HbA_1c (versus those with normal FPG and HbA_1c). Addition of elevated HbA_1c to the model with IFG resulted in improved discrimination and calibration.

CONCLUSIONS

Older adults with both IFG and elevated HbA_1c have a substantially increased odds of developing diabetes over 7 years. Combined screening with FPG and HbA_1c may identify older adults at very high risk for diabetes.Impaired fasting glucose (IFG) (100–125 mg/dL) has been traditionally used for identifying persons at high risk for the subsequent development of diabetes in the U.S. Recent guidelines have additionally endorsed the use of HbA_1c 5.7–6.4% to identify those at risk (1). However, multiple studies, including one conducted among older persons (2), suggest that HbA_1c may identify different individuals at risk for diabetes than traditional glucose measures (3–6). Although several recent investigations confirm that HbA_1c is strongly predictive of future diabetes in predominantly middle-aged populations (7–10), less is known about how well HbA_1c identifies older persons at risk for diabetes.Despite the high prevalence of type 2 diabetes in the elderly (10.9 million Americans in 2010) and the high incidence (390,000 new cases in 2010) of late-onset type 2 diabetes (>65 years) (11,12), there are few specific studies on prediction of diabetes in this group. One such study, based on an earlier Health, Aging, and Body Composition (Health ABC) analysis, developed a prediction rule for diabetes development, which included several factors: advanced age, female sex, elevated fasting plasma glucose (FPG), and triglyceride levels (13). However, HbA_1c was not examined as a potential predictor. In the Cardiovascular Health Study of men and women ≥65 years of age, BMI, waist-to-hip ratio, and weight gain were associated with a higher risk of diabetes, but the impact of glycemic measures on diabetes was not specifically examined (14). An Italian study of older adults (age 65–84 years) found that the combination of abnormal FPG (defined using World Health Organization [WHO] criteria: 110 to <126 mg/dL), increased waist circumference, and HbA_1c ≥7.0% increased the probability of incident diabetes roughly 14-fold (15). However, neither a direct comparison of current prediabetes categories (based upon FPG and HbA_1c) for prediction of diabetes nor an analysis of the utility of combined testing has previously been conducted in this population.We therefore evaluated the odds for diabetes based upon baseline IFG and elevated HbA_1c among the participants of the longitudinal Health ABC study. We directly compared FPG- and HbA_1c-based criteria for predicting the eventual development of diabetes, and we evaluated the utility of combined testing for identifying older persons who develop diabetes. Since HbA_1c values are consistently higher in blacks compared with whites (3,16), we additionally explored race differences in diabetes prediction.     

Are Patients' Views on Seclusion Associated With Lack of Privacy in the Ward?

The lack of single-bed rooms in psychiatric wards may reduce the possibility of patients getting sufficient rest and privacy and may increase their risk of being overstimulated. This study explored whether residing in single- versus multiple-bed rooms in a psychiatric ward was associated with psychiatric patients' opinions about seclusion. More specifically, it was studied whether patients who had shared a room with other patients prior to seclusion rated seclusion more favorably. It was thought that they would rate seclusion more favorably due to the lack of rest they previously experienced in their regular room. For this, the Patient View-of-Seclusion Questionnaire of Hammill, McEvoy, Koral, and Schneider [Hammill, K., McEvoy, J., Koral, H., & Schneider, N. (1989). Hospitalized schizophrenic patient views about seclusion. Journal of Clinical Psychiatry, 50, 174-177] was completed by 54 secluded adult patients hospitalized in a locked ward of a Dutch psychiatric hospital. A significant association was found between residing in multiple-bed rooms prior to seclusion and a less negative view on seclusion. This finding suggests that the ward environment may have a rather large impact on how seclusion is perceived. The results underline the need for single-bed rooms in the treatment of psychiatric inpatients.     

Increases in Neuronal Activity in Rat Spinal Trigeminal Nucleus Following Changes in Barometric Pressure—Relevance for Weather‐Associated Headaches?

Objective.— To determine whether controlled changes in barometric pressure activate rat spinal trigeminal neurons as a possible animal correlate of headaches. Background.— Changes in weather accompanied by changes in atmospheric pressure are suggested to trigger primary headaches. Mechanisms that increase neuronal activity in the rat spinal trigeminal nucleus may parallel those that contribute to the generation of headaches. Methods.— Urethane anesthetized rats were placed in a climatic chamber, in which the air pressure could be selectively manipulated. The parietal cranial dura mater and the spinal dura mater covering the medulla were exposed. Electrolyte‐filled electrodes were introduced into the spinal trigeminal nucleus to record from neurons with receptive fields in facial areas and the cranial dura mater and/or the cornea and/or the temporal muscle. Arterial pressure and heart rate were monitored. The barometric pressure was lowered by 40 hPa during 8 minutes, kept at this level for 8 minutes and returned to the previous level. Results.— During lowering of the barometric pressure and the low pressure period a sample of neurons showed increased discharge rates. Group analysis revealed that it was the group of units with receptive fields in the cornea, but not in the dura mater or the temporal muscle, which was significantly activated when the animal was exposed to low atmospheric pressure. Exposure of the cranial dura and opening of the cisterna magna did not prevent an increase in activity. In another sample of units the activity recorded after infusion of the nitric oxide donor sodium nitroprusside did not change under low pressure exposure. Arterial pressure and heart rate changed slightly during barometric pressure changes. Conclusions.— We conclude that distinct neurons in the trigeminal nucleus caudalis, particularly with preferential afferent input from the eye, respond to lowering of atmospheric pressure. Similar mechanisms may contribute to the generation of headaches during changes in weather.     

How Are Physical Activity,Fitness, and Sedentary Behavior Associated With Insulin Sensitivity in Children?

OBJECTIVE

To describe the associations among moderate-to-vigorous physical activity (MVPA), fitness, sedentary behavior (SB), and insulin sensitivity (IS).

RESEARCH DESIGN AND METHODS

Data were drawn from the baseline assessment of the QUALITY cohort, which included 630 white youth (aged 8–10 years at recruitment), with at least one obese biological parent. IS was measured by two fasting indices (insulin, homeostasis model assessment of insulin resistance) and an oral glucose tolerance test (OGTT)–based index (Matsuda IS index [Matsuda-ISI]). Fitness was measured by Vo_2peak; percent fat mass (PFM) was measured by dual-energy X-ray absorptiometry; 7-day MVPA was measured with accelerometry. SB indicators included average hours daily of self-report screen time (SBst), and average minutes daily at <100 counts/min from accelerometry (SBacc). Multivariable linear regression models were adjusted for age, sex, season, and puberty.

RESULTS

MVPA and SBacc were independently associated with IS, but this was no longer statistically significant after accounting for PFM. SBst was negatively associated with IS in girls only, even after controlling for physical activity (PA), fitness, and adiposity; for each additional hour of SBst daily, IS decreased by 4.6–5.6% across all IS indices. Fitness was positively associated with IS (measured by Matsuda-ISI) after accounting for PA, SB, and PFM; for every 1 unit increase in Vo_2peak, Matsuda-ISI increased by approximately 1.0% (P < 0.05).

CONCLUSIONS

In children with an obese parent, PA and SBacc are associated with IS, but this association is mediated by adiposity. SBst is negatively associated with IS in girls, beyond its known impact on adiposity. Finally, fitness is independently associated with better IS measured by OGTT.In adults, insulin resistance is an independent predictor of type 2 diabetes mellitus, hypertension, coronary heart disease, stroke, and cancer. In several large population–based studies in youth (1,2), clustering of cardiovascular disease (CVD) risk factors is highest among children and adolescents with the lowest levels of insulin sensitivity (IS), suggesting that youth with low IS may be at the highest risk for developing CVD, type 2 diabetes mellitus, and premature mortality.Physical activity (PA) promotes IS through numerous pathways, including increased numbers of GLUT4 transporter proteins (which are responsible for intracellular transport of glucose) and their redistribution, an increase in muscle mass (and specifically an increase in insulin-sensitive muscle fibers), as well as capillary recruitment and proliferation and enhanced cellular insulin signaling (3,4). It is unknown whether higher levels of PA translate into clinically meaningful increases in IS in children, however, with some but not all studies reporting a beneficial effect of PA on IS. Thomas et al. (5) measured intravenous glucose tolerance (which primarily reflects glucose uptake and utilization by skeletal muscle, and encompasses IS) and resting energy expenditure in 32 adolescents aged 12–18 years. They reported that PA measured by accelerometry was positively correlated with both better glucose tolerance and higher resting energy expenditure. Likewise, in a randomized crossover trial of exercise training over 4 months in 79 healthy obese children aged 7–11 years, exercise training was associated with improved fasting insulin; moreover, these benefits dissipated when the children became less active (6). In contrast, there is evidence that the association of PA and cardiometabolic outcomes is largely explained by increased fitness (7).Conflicting results have also been reported in cross-sectional studies examining the relationship between cardiorespiratory fitness and IS. Allen et al. (8), Kasa-Vubu et al. (9), and Ruiz et al. (10) all found that fitness was independently associated with IS, even after controlling for adiposity, suggesting that the negative impact of adiposity on IS may be counteracted by greater cardiorespiratory fitness (10). In contrast, Ball et al. (11) and Lee et al. (12) found that fitness measured by Vo_2max was not associated with IS when adiposity (measured by dual-energy X-ray absorptiometry [DXA]) was taken into account, suggesting that the effect of fitness on IS is indirect and likely a function of body composition. Although inconsistencies across studies may be methodological in origin, the underlying mechanisms of associations between both PA and fitness with IS in youth remain uncertain.Sedentary behavior (SB) is increasingly being investigated as an entity distinct from physical inactivity. A cross-sectional study of 496 Australian 10th grade students suggested that, among boys with >2 h of screen time daily on weekdays, the risk of abnormal levels of insulin and homeostasis model assessment of insulin resistance (HOMA-IR) is twice that of those with less than 2 h after controlling for pubertal status, adiposity, dietary habits, and endurance (13). In contrast, there were no associations between screen time and metabolic risk factors, including lipids, blood pressure, insulin, glucose, and C-reactive protein in girls (13). These results suggest that there may be an increased risk of insulin resistance in boys who accumulate high amounts of screen time. Data from a Norwegian study (n = 86, aged 7–13 years) found that, after controlling for weight status, screen time was statistically significantly and positively associated with increased insulin resistance measured by HOMA-IR in both boys and girls and that this was independent of PA levels (14).Only 7% of Canadian children are currently meeting the new PA guidelines of 60 min/day (15). Furthermore, Canadian youth aged 10–16 years accumulate on average 6 h/day of screen time on weekdays and more than 7 h/day on weekends, well beyond the recommended daily maximum of 2 h (15). No study to date has examined the relative contribution of PA, fitness, and SB to IS in youth. Understanding the independent impact of these three modifiable risk factors on IS is essential to the development of effective preventive strategies against both type 2 diabetes mellitus and CVD. Our objectives were to determine the independent associations among fitness, PA, SB, and IS; to assess whether these associations differ by sex; and to determine whether fitness modifies the association between PA and IS.     

A Novel Use of Structural Equation Models to Examine Factors Associated With Prediabetes Among Adults Aged 50 Years and Older: National Health and Nutrition Examination Survey 2001–2006

OBJECTIVE

To use structural modeling to test a hypothesized model of causal pathways related with prediabetes among older adults in the U.S.

RESEARCH DESIGN AND METHODS

Cross-sectional study of 2,230 older adults (≥50 years) without diabetes included in the morning fasting sample of the 2001–2006 National Health and Nutrition Examination Surveys. Demographic data included age, income, marital status, race/ethnicity, and education. Behavioral data included physical activity (metabolic equivalent hours per week for vigorous or moderate muscle strengthening, walking/biking, and house/yard work), and poor diet (refined grains, red meat, added sugars, solid fats, and high-fat dairy). Structural-equation modeling was performed to examine the interrelationships among these variables with family history of diabetes, high blood pressure, BMI, large waist (waist circumference: women, ≥35 inches; men, ≥40 inches), triglycerides ≥200 mg/dL, and total and HDL (≥60 mg/dL) cholesterol.

RESULTS

After dropping BMI and total cholesterol, our best-fit model included three single factors: socioeconomic position (SEP), physical activity, and poor diet. Large waist had the strongest direct effect on prediabetes (0.279), followed by male sex (0.270), SEP (−0.157), high blood pressure (0.122), family history of diabetes (0.070), and age (0.033). Physical activity had direct effects on HDL (0.137), triglycerides (−0.136), high blood pressure (−0.132), and large waist (−0.067); poor diet had direct effects on large waist (0.146) and triglycerides (0.148).

CONCLUSIONS

Our results confirmed that, while including factors known to be associated with high risk of developing prediabetes, large waist circumference had the strongest direct effect. The direct effect of SEP on prediabetes suggests mediation by some unmeasured factor(s).The growing prevalence of diabetes, combined with clear evidence that lifestyle change can reduce diabetes risk in high-risk individuals, has led the American Diabetes Association to recommend diabetes screening in clinical settings for adults aged ≥45 years who have no risk factors other than age (1). Persons with blood glucose levels that are higher than those considered normal but not high enough to be classified as diabetes are at increased risk for type 2 diabetes (2,3). This state is termed “prediabetes,” and its prevalence in 2005–2008, based on fasting glucose or HbA_1c levels, reached 50% for U.S. adults aged ≥65 years. For this age group, diagnosed diabetes is projected to reach 26.7 million by 2050, or 55% of all diabetes cases (4). In 2007, spending on diabetes care for adults aged ≥65 years accounted for $64.8 billion (56%) of direct diabetes medical costs—$41.1 billion for institutional care alone. Identifying older adults with prediabetes may help delay or prevent type 2 diabetes, thereby reducing morbidity and healthcare costs.After adjusting for race/ethnicity, sex, and age, prediabetes is associated with obesity (5), high blood pressure (6), lipid abnormalities (7), family history of diabetes (8), and specific physical activity and dietary patterns (9). To our knowledge, no studies have examined all of these factors simultaneously as a system of multiple pathways leading to prediabetes. Available research allows us to hypothesize a causal model that depicts the relationships of factors related to the development of prediabetes in terms of direct effects and indirect (i.e., mediator) effects. Unlike traditional regression models that treat each covariate in the model as an independent direct effect on prediabetes, we can assess all relevant pathways of reported factors as independent and/or dependent (i.e., mediator) factors leading to prediabetes at once. Focusing our analysis on adults aged ≥50 years provides information that could stimulate thinking concerning ways to reduce diabetes risk for the Medicare population and those who will soon be in the Medicare population. As such, we used structural-equation modeling to test our hypothesized model, using data from a nationally representative survey of the U.S. population.     

What Are the Determinants of Dental Care Expenditures in Institutions for Adults With Disabilities? Findings From a National Survey

Objective

To analyze the determinants of dental care expenditures in institutions for adults with disabilities.

Who Moves After SCI? Individual,Health, and Neighborhood Predictors of Residential Mobility Among Participants in the National Spinal Cord Injury Model Systems Database

ObjectiveTo investigate residential mobility among community-living adults with spinal cord injury (SCI) and the individual, health, and neighborhood factors associated with the propensity to relocate.DesignRetrospective analysis of data from the National SCI Model Systems (SCIMS) Database collected between 2006 and 2018 and linked with the American Community Survey 5-year estimates.SettingCommunity.InterventionsNot applicable.ParticipantsPeople with traumatic SCI (N=4599) who participated in 2 waves of follow-up and had residential geographic identifiers at the census tract level.Main Outcome MeasuresMoving was a binary measure reflecting change in residential locations over a 5-year interval. Move distance distinguished nonmovers from local movers (different tracts within the same county) and long-distance movers (to different county or state). Move quality included 4 categories: stayed/low poverty tract, stayed/high poverty tract, moved/low poverty tract, and moved/high poverty tract.ResultsOne in 4 people moved within a 5-year interval (n=1175). Of the movers, 55% relocated to a different census tract within the same county and 45% relocated to a different county or state. Thirty-five percent of all movers relocated to a high poverty census tract. Racial and ethnic minorities, people from low-income households, and younger adults were more likely to move, move locally, and relocate to a high poverty neighborhood. High poverty and racial/ethnic segregation in the origin neighborhood predicted an increased risk for remaining in or moving to a high poverty neighborhood.ConclusionsAlthough people with SCI relocated at a lower rate than has been reported in the general population, moving was a frequent occurrence postinjury. People from vulnerable groups were more likely to remain in or relocate to socioeconomically disadvantaged neighborhoods, thus increasing the risk for health disparities and poorer long-term outcomes among minorities and people from low-income households. These findings inform policy makers’ considerations of housing, health care, and employment initiatives for individuals with SCI and other chronic disabilities.