Pasos Hacia La Salud II: A Superiority RCT Utilizing Technology to Promote Physical Activity in Latinas

INTRODUCTION

Latinas face an increased risk for chronic diseases associated with insufficient physical activity (PA). The researchers previously showed that a website-based intervention could increase PA among insufficiently active Latinas, yet rates of meeting national PA guidelines were low. The original intervention was enhanced by adding additional features, content, and points of contact, including via text messaging. This study tests the efficacy of the enhanced intervention compared with the original, aimed at maximizing and sustaining PA gains across 24 months. It also examines if increases in PA differed by baseline PA.

STUDY DESIGN

The researchers conducted a superiority randomized controlled trial (data collected 2018-2022, analyzed 2023).

SETTING/PARTICIPANTS

Participants were 195 Spanish-speaking Latinas ages 18-65 in the Providence, RI area.

INTERVENTION

The original intervention is an empirically supported Spanish-language, individually-tailored, website-delivered PA intervention. The enhanced intervention includes text messaging and additional data-driven content and interactive features.

MAIN OUTCOME MEASURES

Total weekly minutes of moderate to vigorous PA (MVPA) was measured via accelerometry and self-report at 6, 12, 18, and 24 months.

RESULTS

Participants in both groups increased their MVPA over 24 months. There were no significant between-group differences at 6 or 12 months; at 18 months the enhanced intervention group had higher levels of self-reported (mean (sd): 90.35 (43.55) vs 70.18 [9.99]) and accelerometer-measured (66.21 [18.26] vs 60.27 [16.00]) MVPA compared to the original intervention group. They also had higher levels of self-reported (111.17 [23.35] vs 81.44 [1.82]) and accelerometer-measured (63.76 [15.12] vs 54.86 [14.59]) MVPA at 24 months. Baseline PA moderated the intervention effect.

CONCLUSIONS

This study demonstrates the potential to enhance the efficacy of website-based PA interventions by utilizing text messaging, and adding more interactive features, content, and phone support. These enhancements may be particularly beneficial in supporting long-term PA maintenance.

TRIAL REGISTRATION

This study is registered at www.

CLINICALTRIAL

gov (NCT03491592).

Availability of Recreation Facilities and Parks In Relation to Adolescent Participation in Organized Sports and Activity Programs

Most adolescents do not meet physical activity guidelines, so understanding facilitators and barriers is important. This study used surveys and geocoded location data to examine associations of availability of parks and recreation facilities with adolescent-reported participation in organized team sports and physical activity classes. The study was conducted with 928 adolescents aged 12-17 years, plus one parent/caretaker, recruited from two regions of the US. Adolescents' participation in teams and classes was positively associated with parents' perceptions of multiple available recreation environments, but not with objectively-measured availability. Having multiple nearby parks and recreation facilities may provide adolescents with more options for participating in preferred organized team sports and activity classes.

Density and Fat Fraction of the Psoas, Paraspinal, and Oblique Muscle Groups Are Associated With Lumbar Vertebral Bone Mineral Density in a Multi-Ethnic Community-Living Population: The Multi-Ethnic Study of Atherosclerosis

Low vertebral bone mass is a major risk factor for vertebral compression fractures. Although sarcopenia has been shown to be associated with low bone mineral density (BMD), it is not known whether trunk musculature is directly associated with lumbar BMD, and whether exercise modifies this association. Using data from the Multi-Ethnic Study of Atherosclerosis (MESA), we sought to determine the association of muscle density and fat fraction of the psoas, paraspinal, and oblique muscle groups with L₃ lumbar volumetric BMD, and whether these associations were modified by exercise. We obtained L₃ vBMD measurements, and fat and muscle measurements (in Hounsfield units [HU]) from abdominal computed tomography (CT) scans spanning the L₂ -L₄ intervertebral disc spaces. Muscle density was defined as the mean HU value for a muscle group area. Fat fraction was calculated as the mean HU value for the muscle group fat area/total muscle group area (cm² ). Exercise data were self-reported (MET-minute/week). We utilized multivariable linear regression to evaluate these associations, stratified by gender, and adjusting for demographics, body mass index (BMI), smoking status, impaired fasting glucose, and corticosteroid and anti-resorptive medication use. Among 1923 MESA participants, mean ± standard deviation (SD) age was 62 ± 10 years, 49% were female, 40% white, 21% black, 26% Hispanic/Latino, and 13% Chinese. In fully adjusted analysis, for every 1-SD higher psoas fat fraction, there was a 3.19-SD lower L₃ vBMD in men and 4.3-SD lower L₃ vBMD in women (p < 0.001). For every 1-SD higher psoas density, there was a 0.2-SD higher L₃ vBMD (p < 0.001) in men and 0.19-SD higher L₃ vBMD (p < 0.001) in women. Findings were similar for paraspinal and oblique muscles. Intentional exercise did not modify these associations. In men and women, trunk muscle density was positively associated with higher lumbar BMD, suggesting a local association. Future studies are warranted to determine the temporality of this association. © 2022 American Society for Bone and Mineral Research (ASBMR).

Pasos Hacia La Salud II: study protocol for a randomized controlled trial of a theory- and technology-enhanced physical activity intervention for Latina women, compared to the original intervention

Background

Latinas are at increased risk for many lifestyle-related chronic diseases and are one of the least physically active populations in the US Innovative strategies are needed to help Latinas achieve the health benefits associated with physical activity (PA). This manuscript describes the study protocol of the Pasos Hacia La Salud II Study, which builds upon our previous research to test an enhanced individually-tailored, text-message and website-delivered, Spanish-language intervention (enhanced intervention), in comparison to the original web-based Pasos Hacia La Salud Intervention (original intervention).

Methods

Sedentary Latinas between the ages of 18–65 will be recruited and will complete an orientation and baseline assessments. Participants will be subsequently randomized to the original intervention, or the Enhanced Intervention, which has greater targeting of theoretical constructs such as self-efficacy, enjoyment, and social support, and which uses text messages and more dynamic and refined website features to encourage increased website use. Using a linear mixed effects regression model, we will simultaneously estimate the intervention effects on mean accelerometer-measured hours/week of moderate-to-vigorous PA (MVPA) at 6, 12, 18, and 24 months, with a subject-specific intercept (intent-to-treat sample). Change in self-reported MVPA, measured via the 7-day Physical Activity Recall, will be assessed as a secondary outcome using a similar model. We will investigate potential mediators of the intervention effect using a multiple mediation approach, and potential moderators by evaluating potential interactions. As an exploratory outcome, we will study the differences (among both study arms) in cost, in US dollars, per minute increases in weekly mean MVPA.

Discussion

The original Pasos PA intervention showed efficacy in helping Latinas increase PA; we expect the Enhanced Intervention to help a larger proportion of participants to increase and maintain their PA long term. This web- and text-based enhanced intervention could have great reach and dissemination potential, which could be capitalized on in the future to help to advance health equity. Adaptations made in response to the COVID-19 pandemic are also described in this manuscript.

Trial registration

Clinical Trial Number: NCT03491592. First posted April 9, 2018.

Association of abdominal muscle area and density with glucose regulation: The multi-ethnic study of atherosclerosis (MESA)

AIMS

Previous characterisation of body composition as a type 2 diabetes mellitus (T2DM) risk factor has largely focused on adiposity, but less is known about the independent role of skeletal muscle. We examined associations between abdominal muscle and measures of glucose regulation.

MATERIALS AND METHODS

Cross-sectional analysis of 1,891 adults enrolled in the Multi-Ethnic Study of Atherosclerosis. Multivariable regression assessed associations between abdominal muscle area and density (measured by computed tomography) with fasting glucose, homeostasis model assessment of insulin resistance (HOMA-IR), and prevalent T2DM (fasting glucose ≥126 mg/dL or medication use).

RESULTS

In minimally adjusted models (age, sex, race/ethnicity, income), a 1-SD increment in abdominal muscle area was associated with higher HOMA-IR (β = 0.20 ± SE 0.03; 95%CI: 0.15, 0.25; P < 0.01) and odds of T2DM (OR = 1.47; 95%CI: 1.18, 1.84; P < 0.01), while higher density was associated with lower fasting glucose (-4.49 ± 0.90; -6.26, -2.72; P < 0.01), HOMA-IR (-0.16 ± 0.02; -0.20, -0.12; P < 0.01), and odds of T2DM (0.64; 0.52, 0.77; P < 0.01). All associations persisted after adjustment for comorbidities and health behaviours. However, after controlling for height, BMI, and visceral adiposity, increasing muscle area became negatively associated with fasting glucose (-2.23 ± 1.01; -4.22, -0.24; P = 0.03), while density became positively associated with HOMA-IR (0.09 ± 0.02; 0.05, 0.13; P < 0.01).

CONCLUSIONS

Increasing muscle density was associated with salutary markers of glucose regulation, but associations inverted with further adjustment for body size and visceral adiposity. Conversely, after full adjustment, increasing muscle area was associated with lower fasting glucose, suggesting some patients may benefit from muscle-building interventions.

Randomized Trial of a Physical Activity Intervention for Latino Men: Activo

INTRODUCTION

Latino men experience disproportionately high rates of diseases related to low physical activity, yet they are poorly represented in physical activity intervention trials. Efforts to promote physical activity in Latina women show promising results, yet such interventions are yet to be extended to Latino men. This study tested a computer expert system‒tailored, text messaging-supported physical activity intervention for underactive Spanish-speaking Latino men compared with a control group matched for contact time. Potential predictors of intervention success were also explored.

STUDY DESIGN

Randomized trial. Participants were randomized to receive a Tailored Physical Activity Intervention (Intervention) or a Wellness Control (Control). Data were collected in 2015-2017 and analyzed in 2018-2019.

SETTING/PARTICIPANTS

Insufficiently active Latino men (n=46).

INTERVENTION

Intervention participants received a baseline counseling session and then, individually tailored print materials and text messages on a tapered schedule for 6 months. Control participants received printed wellness materials and text messages on the same schedule.

MAIN OUTCOME MEASURES

Primary outcome was a change in weekly moderate to vigorous physical activity from baseline to 6 months measured by accelerometers. Self-reported moderate to vigorous physical activity measured by the 7-day Physical Activity Recall Interview was a secondary outcome.

RESULTS

For Intervention participants, median accelerometer-measured moderate to vigorous physical activity increased from 10.0 minutes/week at baseline to 57.5 minutes/week at 6 months, whereas for Control participants, it increased from 21.0 minutes/week at baseline to 23.0 minutes/week at 6 months (p<0.05). Similar results were found for self-reported moderate to vigorous physical activity. At 6 months, 47% of Intervention participants met national guidelines of 150 minutes/week versus 25% of Control participants (p=0.15, not significant).

CONCLUSIONS

Findings suggest that an individually tailored intervention can successfully increase moderate to vigorous physical activity in underactive Latino men. Such technology-supported interventions have the potential for broad dissemination.

TRIAL REGISTRATION

This study is registered at www.clinicaltrials.gov NCT02512419.

Design and rationale for a randomized trial of a theory- and technology- enhanced physical activity intervention for Latinas: The Seamos Activas II study

INTRODUCTION

Latina women report disproportionately high rates of physical inactivity and related chronic health conditions. Physical activity (PA) efforts to date have shown modest success in this at-risk population; thus, more effective interventions are necessary to help Latinas reach national PA guidelines and reduce related health disparities. This paper describes the design, rationale, and baseline findings from the Seamos Activas II intervention.

METHODS/DESIGN

The ongoing RCT will test the efficacy of the Seamos Saludables PA print intervention vs. a theory-and technology-enhanced version (Seamos Activas II). The purpose of the study is to increase the percentage of Latinas meeting the national PA guidelines compared to the prior trial, improve biomarkers related to disease, and extend generalizability to a broader and more representative population of Latinas (i.e. Mexican/Mexican-Americans). Intervention refinements included further targeting key constructs of Social Cognitive Theory, and incorporating interactive text message-based self-monitoring strategies. The primary outcome is change in minutes per week of MVPA measured by ActiGraph GT3X+ accelerometers at 6- and 12-months. Secondary PA outcomes assessed by the 7-Day PA Recall will be used to corroborate findings.

RESULTS

Participants (N = 199) are Latinas 18-65 years (mean = 43.8) of predominantly Mexican origin (89%). At baseline, objectively measured MVPA was 39.51 min/week (SD = 71.20, median = 10) and self-reported MVPA was 12.47 min/week (SD = 22.54, median = 0).Participants reported generally low self-efficacy and higher cognitive vs. behavioral processes of change.

CONCLUSION

Addressing interactivity and accountability through text messaging, and more rigorously targeting theoretical constructs may be key to helping Latinas achieve nationally recommended PA levels and thereby reducing health disparities.

Associations of abdominal muscle area and density with coronary artery calcium volume and density: The multi-ethnic study of atherosclerosis

BACKGROUND

Due to the opposing cardiovascular risk profiles of CAC volume and density, we tested the hypothesis that increased abdominal muscle area (AMA) and density (AMD) were significantly associated with lower coronary arterial calcium (CAC) volume and higher CAC density.

METHODS

Using data from 787 participants from the Multi-Ethnic Study of Atherosclerosis, Ancillary Body Composition Study, we analyzed abdominal and chest computed tomography (CT) scans. Abdominal scans were scored for muscle area, muscle density (attenuation) and visceral and subcutaneous fat. Chest scans were scored for CAC volume and Agatston values, which were used to derive CAC density scores.

RESULTS

The mean (SD) age and BMI of the participants was 67.8 (9.0) years and 27.9 (4.8) kg/m², respectively. Forty-one percent were female, 46% were Caucasian, 60% had hypertension, 17% had diabetes, and 46% had dyslipidemia. AMA was positively associated with CAC volume (p < .001) and inversely associated with CAC density (p < .001). Conversely, AMD was inversely associated with CAC volume and positively associated with CAC density in minimally adjusted models (p < .001), but not significant in confounder adjusted models.

CONCLUSION

AMA and AMD had differing associations with CAC volume and density, with AMA significantly associated with a higher risk CAC profile (high volume, low density) and AMD not significantly associated with CAC volume or density. Future research needs to account for the unique components of both muscle composition and CAC.

Modelling multiple health behavior change with network analyses: results from a one-year study conducted among overweight and obese adults

This study examined the between-person associations of seven health behaviors in adults with obesity participating in a weight loss intervention, as well as the covariations between these behaviors within-individuals across the intervention. The present study included data from a 12-month weight loss trial (N = 278). Seven health behaviors (physical activity, sedentary behavior, sleep duration, and consumption of fruits, vegetables, total fat and added sugar) were measured at baseline, 6- and 12-months. Between- and within-participants network analyses were conducted to examine how these behaviors were associated through the 12-month intervention and covaried across months. At the between-participants level, associations were found within the different diet behaviors and between total fat and sedentary behaviors. At the within-participants level, covariations were found between sedentary and diet behaviors, and within diet behaviors. Findings suggest that successful multiple health behaviors change interventions among adults with obesity will need to (1) simultaneously target sedentary and diet behaviors; and (2) prevent potential compensatory behaviors in the diet domain.

The FIREBIRD-II CubeSat mission: Focused investigations of relativistic electron burst intensity, range, and dynamics

FIREBIRD-II is a National Science Foundation funded CubeSat mission designed to study the scale size and energy spectrum of relativistic electron microbursts. The mission consists of two identical 1.5 U CubeSats in a low earth polar orbit, each with two solid state detectors that differ only in the size of their geometric factors and fields of view. Having two spacecraft in close orbit allows the scale size of microbursts to be investigated through the intra-spacecraft separation when microbursts are observed simultaneously on each unit. Each detector returns high cadence (10 s of ms) measurements of the electron population from 200 keV to >1 MeV across six energy channels. The energy channels were selected to fill a gap in the observations of the Heavy Ion Large Telescope instrument on the Solar, Anomalous, and Magnetospheric Particle Explorer. FIREBIRD-II has been in orbit for 5 years and continues to return high quality data. After the first month in orbit, the spacecraft had separated beyond the expected scale size of microbursts, so the focus has shifted toward conjunctions with other magnetospheric missions. FIREBIRD-II has addressed all of its primary science objectives, and its long lifetime and focus on conjunctions has enabled additional science beyond the scope of the original mission. This paper presents a brief history of the FIREBIRD mission's science goals, followed by a description of the instrument and spacecraft. The data products are then discussed along with some caveats necessary for proper use of the data.

Associations of recreational and non-recreational physical activity with coronary artery calcium density vs. volume and cardiovascular disease events: the Multi-Ethnic Study of Atherosclerosis

AIMS

The benefits of physical activity (PA) on cardiovascular disease (CVD) are well known. However, studies suggest PA is associated with coronary artery calcium (CAC), a subclinical marker of CVD. In this study, we evaluated the associations of self-reported recreational and non-recreational PA with CAC composition and incident CVD events. Prior studies suggest high CAC density may be protective for CVD events.

METHODS AND RESULTS

We evaluated 3393 participants of the Multi-Ethnic Study of Atherosclerosis with prevalent CAC. After adjusting for demographics, the highest quintile of recreational PA was associated with 0.07 (95% confidence interval 0.01-0.13) units greater CAC density but was not associated with CAC volume. In contrast, the highest quintile of non-recreational PA was associated with 0.08 (0.02-0.14) units lower CAC density and a trend toward 0.13 (-0.01 to 0.27) log-units higher CAC volume. There were 520 CVD events over a 13.7-year median follow-up. Recreational PA was associated with lower CVD risk (hazard ratio 0.88, 0.79-0.98, per standard deviation), with an effect size that was not changed with adjustment for CAC composition or across levels of prevalent CAC.

CONCLUSION

Recreational PA may be associated with a higher density but not a higher volume of CAC. Non-recreational PA may be associated with lower CAC density, suggesting these forms of PA may not have equivalent associations with this subclinical marker of CVD. While PA may affect the composition of CAC, the associations of PA with CVD risk appear to be independent of CAC.

Association Between Physical Activity Intervention Website Use and Physical Activity Levels Among Spanish-Speaking Latinas: Randomized Controlled Trial

Background

The internet’s low cost and potential for high reach makes Web-based channels prime for delivering evidence-based physical activity (PA) interventions. Despite the well-studied success of internet-based PA interventions in primarily non-Hispanic white populations, evidence on Spanish-speaking Latinas’ use of such interventions is lacking. The recent rise in technology use among Latinas in the United States, a population at heightened risk for low PA levels and related conditions, suggests that they may benefit from Web-based PA interventions tailored to their cultural and language preferences.

Objective

The goal of the research was to examine participant engagement with various features of an internet-based PA intervention for Latinas and explore how use of these features was differentially associated with adoption and maintenance of PA behavior change.

Method

Pasos Hacia la Salud tested a Spanish-language, culturally adapted, individually tailored, internet-based PA intervention versus a Spanish language, internet-based, Wellness Contact Control condition for underactive Latinas (N=205, mean age 39.2 [SD 10.5] years, 84% Mexican American). These analyses examined engagement with the website and explored how use was associated with adoption and maintenance of moderate to vigorous physical activity (MVPA) behavior.

Results

Overall, participants logged on to the website an average of 22 times (SD 28) over 12 months, with intervention participants logging on significantly more than controls (29 vs 14.7, P<.001). On average, participants spent more time on the website at months 1, 4, and 6 compared to all other months, with maximum use at month 4. Both log-ins and time spent on the website were significantly related to intervention success (achieving higher mean minutes of MVPA per week at follow-up: b=.48, SE 0.20, P=.02 for objectively measured MVPA and b=.74, SE 0.34, P=.03 for self-reported MVPA at 12 months, controlling for baseline). Furthermore, those meeting guidelines by the Centers for Disease Control and Prevention for PA at 12 months (≥150 minutes per week of MVPA) logged on significantly more than those not meeting guidelines (35 vs 20 over 12 months, P=.002). Among participants in the intervention arm, goal-setting features, personal PA reports, and PA tips were the most used portions of the website. Higher use of these features was associated with greater success in the program (significantly more minutes of self-reported MVPA at 12 months controlling for baseline). Specifically, one additional use of these features per month over 12 months translated into an additional 34 minutes per week of MVPA (goals feature), 12 minutes per week (PA tips), and 42 minutes per week (PA reports).

Conclusions

These results demonstrate that greater use of a tailored, Web-based PA intervention, particularly certain features on the site, was significantly related to increased PA levels in Latinas.

Trial Registration

ClinicalTrials.gov NCT01834287; https://clinicaltrials.gov/ct2/show/NCT01834287

Effect of a moderate-intensity demonstration walk on accuracy of physical activity self-report

Background/Objective

Providing a demonstration of a 10-minute bout of moderate-to-vigorous intensity physical activity (MVPA) immediately prior to subjective reporting of MVPA could influence self-reported activity by calibrating both duration and intensity. We assessed the effect of a demonstration of MVPA on subsequent MVPA recall, and explored whether this improved agreement with objective measures of MVPA.

Methods

A total of 846 individuals participated in four different physical activity interventions; two of which included a 10-minute moderate-intensity demonstration walk on a treadmill at baseline and 6-month visits immediately prior to reporting MVPA. Participants from three studies also wore accelerometers during the week overlapping with self-reported MVPA.

Results

Overall, those completing the demonstration walk reported significantly fewer minutes of MVPA per week at baseline (b = −11.69, standard error = 2.53, p < 0.01). The effect of the demonstration walk at 6 months was not significant (p = 0.06). Correlations with accelerometers at baseline were higher in the two studies with the demonstration walk (ρ = 0.28, 0.26) than the study without (ρ = 0.04). Correlations with accelerometers increased overall from baseline to follow-up.

Conclusion

A 10-minute demonstration of MVPA was associated with reporting fewer minutes of MVPA and improved agreement with objective PA measures at baseline. These findings support combining self-report PA assessments with hands-on MVPA demonstrations.

Social support and physical activity change in Latinas: Results from the Seamos Saludables trial

OBJECTIVE

Family responsibilities and poor social support are barriers to physical activity among Latinas. This study evaluated the effects of a home- and print-based intervention on social support, moderating effects of familial ties on support and moderate-to-vigorous physical activity (MVPA), and mediating effects of support on MVPA.

METHOD

Participants were randomized to receive through the mail either individually tailored physical activity intervention or general wellness print materials. Familial ties and social support were assessed by marital and child status and the social support for physical activity measure, respectively. MVPA was measured using the 7-day Physical Activity Recall Interview and accelerometer. Assessments were conducted at baseline, 6 months posttreatment, and 12 months follow-up.

RESULTS

Participants (n = 266; 40.6 ± 9.9 years old) were mostly immigrant and Spanish-speaking Latinas. The intervention group achieved greater increases in family and friend support compared to the wellness control group from baseline to posttreatment and follow-up (p < .05). Intervention changes in support did not depend on marital or child status. The intervention also increased minutes per week of MVPA more than the wellness control (p < .05) and the effect did not depend on marital or child status. There were significant indirect effects of treatment, indicating the intervention achieved greater increases in MVPA by increasing family (ab = 5.21, SE = 2.94, 95% confidence interval [CI] = 0.91-14.11) and friend (ab = 6.83, SE = 5.15, 95% CI = 0.16-20.56) support.

CONCLUSIONS

The intervention improved and sustained support from family and friends and MVPA irrespective of familial ties. Social support mediated increases in MVPA. (PsycINFO Database Record

Promoting Physical Activity among Underserved Populations

Underserved populations, including racial/ethnic minorities, individuals with low socioeconomic status, and individuals with physical disabilities, are less likely to engage in sufficient moderate to vigorous physical activity (MVPA) and are thus at increased risk of morbidity and mortality. These populations face unique challenges to engaging in MVPA. Learning how to overcome these challenges is a necessary first step in achieving health equity through health promotion research. In this review of the literature, we discuss issues and strategies that have been used to promote MVPA among individuals from underserved populations, focusing on recruitment, intervention delivery, and the use of technology in interventions. Physical activity promotion research among these vulnerable populations is scarce. Nevertheless, there is preliminary evidence of efficacy in the use of certain recruitment and intervention strategies including tailoring, cultural adaptation, incorporation of new technologies, and multilevel and community-based approaches for physical activity promotion among different underserved populations.

Pasos Hacia La Salud: a randomized controlled trial of an internet-delivered physical activity intervention for Latinas

Background

Internet access has grown markedly in Latinos during the past decade. However, there have been no Internet-based physical activity interventions designed for Latinos, despite large disparities in lifestyle-related conditions, such as obesity and diabetes, particularly in Latina women. The current study tested the efficacy of a 6-month culturally adapted, individually tailored, Spanish-language Internet-based physical activity intervention.

Methods

Inactive Latinas (N = 205) were randomly assigned to the Tailored Physical Activity Internet Intervention or the Wellness Contact Control Internet Group. Participants in both groups received emails on a tapered schedule over 6 months to alert them to new content on the website. The primary outcome was minutes/week of moderate to vigorous physical activity (MVPA) at 6 months as measured by the 7-Day Physical Activity Recall; activity was also measured by accelerometers. Data were collected between 2011 and 2014 and analyzed in 2015 at the University of California, San Diego.

Results

Increases in minutes/week of MVPA were significantly greater in the Intervention Group compared to the Control Group (mean difference = 50.00, SE = 9.5, p < 0.01). Increases in objectively measured MVPA were also significantly larger in the Intervention Group (mean differences = 31.0, SE = 10.7, p < .01). The Intervention Group was also significantly more likely to meet national physical activity guidelines at 6 months (OR = 3.12, 95 % CI 1.46–6.66, p < .05).

Conclusion

Findings from the current study suggest that this Internet-delivered individually tailored intervention successfully increased MVPA in Latinas compared to a Wellness Contact Control Internet Group.

Trial registration

NCT01834287.

Association of Muscle Mass, Area, and Strength With Incident Diabetes in Older Adults: The Health ABC Study

CONTEXT

Skeletal muscle plays a key role in glucose regulation, yet the association between muscle quantity or quality and the risk of developing type 2 diabetes has not been explored.

OBJECTIVE

The objective of the study was to assess the association between muscle quantity and strength and incident diabetes and to explore whether this association differs by body mass index (BMI) category.

DESIGN AND SETTING

Participants were 2166 older adults in the Health, Aging, and Body Composition Study who were free of diabetes at baseline (1997–1998). Computed tomography and dual-energy x-ray absorptiometry were used to measure abdominal and thigh muscle area and total body lean mass, respectively. Strength was quantified by grip and knee extensions.

MAIN OUTCOME MEASURE

Incident diabetes, defined as fasting glucose of 126 mg/dL or greater, a physician's diagnosis, and/or the use of hypoglycemic medication were measured.

RESULTS

After a median 11.3 years of follow-up, there were 265 incident diabetes cases (12.2%). In fully adjusted models, no association was found between muscle or strength measures and incident diabetes (for all, P > .05). For women, there was a significant interaction with BMI category for both abdominal and thigh muscle, such that greater muscle predicted lower risk of incident diabetes for normal-weight women (hazard ratio 0.37 [0.17–0.83] and 0.58 [0.27–1.27] per SD, respectively) and a greater risk for overweight and obese women (hazard ratio 1.23 [0.98–1.54] and 1.28 [1.00–1.64], respectively). No significant interactions by BMI category existed for strength measures or any measures for men (for all, P > .05).

CONCLUSIONS

Greater muscle area is associated with a lower risk of incident diabetes for older normal-weight women but not for men or overweight women.

Adapting Technological Interventions to Meet the Needs of Priority Populations

Cardiovascular diseases (CVD) comprise the leading cause of mortality worldwide, accounting for 3 in 10 deaths. Individuals with certain risk factors, including tobacco use, obesity, low levels of physical activity, type 2 diabetes mellitus, racial/ethnic minority status and low socioeconomic status, experience higher rates of CVD and are, therefore, considered priority populations. Technological devices such as computers and smartphones are now routinely utilized in research studies aiming to prevent CVD and its risk factors, and they are also rampant in the public and private health sectors. Traditional health behavior interventions targeting these risk factors have been adapted for technology-based approaches. This review provides an overview of technology-based interventions conducted in these priority populations as well as the challenges and gaps to be addressed in future research. Researchers currently possess tremendous opportunities to engage in technology-based implementation and dissemination science to help spread evidence-based programs focusing on CVD risk factors in these and other priority populations.

Type II diabetes disparities in diverse women: the potential roles of body composition, diet and physical activity

The rates of diabetes in the USA are rapidly increasing, and vary widely across different racial/ethnic groups. This paper explores the potential contribution of body composition, diet and physical activity in explaining diabetes disparities across women of different racial and ethnic backgrounds. For body composition, racial/ethnic groups differ widely by BMI, distribution of body mass and quantity and type of adipose tissue. Dietary patterns that vary across race/ethnicity include consumption of meat, added sugars, high-glycemic carbohydrates and fast food. Additionally, physical activity patterns of interest include aerobic versus muscle-strengthening exercises, and the purpose of physical activity (leisure, occupation, or transportation). Overall, these variables provide a partial picture of the source of these widening disparities, and could help guide future research in addressing and reducing diabetes disparities.

Using interactive Internet technology to promote physical activity in Latinas: Rationale, design, and baseline findings of Pasos Hacia La Salud

Internet-based interventions show promise as an effective channel for promoting physical activity. However, a paucity of research has been conducted among underserved groups despite recent increases in Internet access and physical activity-related health disparities in these communities. Thus, the current randomized controlled trial will test the efficacy of an individually tailored, Internet-based physical activity intervention for Latinas. This program was culturally and linguistically adapted for the target population through extensive formative research. Two hundred eighteen sedentary Latinas were randomly assigned to the Tailored Physical Activity Internet Intervention or the Wellness Contact Control Internet Group. The Physical Activity Internet Intervention, based on Social Cognitive Theory and the Transtheoretical Model, utilizes a website with features including self-monitoring, goal setting, discussion forum, links to online resources, individually tailored and motivation-matched physical activity feedback reports, and exercise tip sheets. Participants receive regular emails over the first 6months with a tapered dose during the second 6months (maintenance phase) to alert them to new content on the website. The main outcome is differences in minutes/week of moderate to vigorous physical activity at six months as measured by the 7-Day Physical Activity Recall and accelerometer data. High reach, low cost, culturally relevant Internet-based interventions that encourage physical activity among Latinas could help reduce health disparities and thus have a substantial positive impact on public health.

Pericardial fat is associated with all-cause mortality but not incident CVD: the Rancho Bernardo Study

OBJECTIVE

Pericardial and intra-thoracic fat are associated with prevalent cardiovascular disease (CVD) and CVD risk factors. However, it is unclear if these fat depots predict incident CVD events and/or all-cause mortality. We examined prospective associations between areas of pericardial and intra-thoracic fat and incident CVD and mortality over a 12-year follow-up in a subset of participants without baseline clinical CVD from the Rancho Bernardo Study (RBS).

METHODS

Participants were 343 community-dwelling older adults (mean baseline age = 67) who completed a clinic visit in 2001-02, including a computed tomography scan of the chest. Incident CVD and mortality were recorded through January 2013.

RESULTS

Over a 12.6-year median follow-up, there were 60 incident CVD events and 49 deaths. Pericardial fat was associated with all-cause mortality, such that each standard deviation increment predicted a 34% higher chance of death after adjusting for demographics, lifestyle factors, comorbidities, and visceral fat (95% CI = 1.01-1.78). When categorized by tertile, those in the middle tertile of pericardial fat showed no increased risk of mortality, while those in the highest tertile had 2.6 times the risk (95% CI = 1.10-5.97) compared to the lowest tertile. There was a marginal association between intra-thoracic fat and mortality (p = 0.06). Neither pericardial nor intra-thoracic fat was significantly associated with incident CVD. There were no significant interactions by sex.

CONCLUSIONS

Higher pericardial, but not intra-thoracic, fat was associated with earlier all-cause mortality in older adults over a 12-year follow-up. This association was primarily driven by a higher mortality rate in those in the highest tertile of pericardial fat.

Twelve-month physical activity outcomes in Latinas in the Seamos Saludables trial

BACKGROUND

Physical activity interventions designed for Latinas have shown short-term behavior change, but longer-term change and maintenance is rarely measured.

PURPOSE

To assess physical activity change at 12 months, following 6-month tapered completion of an RCT of a physical activity intervention for Latinas.

METHODS

Two hundred sixty-six underactive (<60 minutes/week physical activity) Latinas were randomized to an individually tailored, culturally and linguistically adapted physical activity intervention, or a wellness contact control. Participants received the materials through the mail for 6 months, then received booster doses at 8, 10, and 12 months. Minutes per week of moderate to vigorous physical activity were measured by the 7-Day Physical Activity Recall interview at baseline and 6 and 12 months. Data were collected at Brown University between 2009 and 2013, and analyses were conducted in 2013.

RESULTS

At 12 months, increases in moderate to vigorous physical activity were significantly greater in the intervention than in the wellness group (mean difference=52 minutes/week, SE=9.38, p<0.01), with both groups showing slight increases in moderate to vigorous physical activity from 6 to 12 months. Intervention participants were also more likely to meet national moderate to vigorous physical activity guidelines (OR=3.14, p=0.01).

CONCLUSIONS

The intervention was more effective than the wellness control at 12 months, and physical activity increases from baseline to 6 months were maintained, suggesting the intervention may lead to sustainable behavior change.

TRIAL REGISTRATION

This study is registered at Clinicaltrials.gov NCT01583140.

The association between abdominal muscle and type II diabetes across weight categories in diverse post-menopausal women

CONTEXT

Despite the key role of muscle in glucose regulation, little is known about the association between muscle area and prevalence of metabolic disorders, or the role low muscle may play in normal weight metabolic obesity.

OBJECTIVE

The objective was to assess the independent associations between both abdominal muscle and fat depositions (measured by computed tomography) and the prevalence of type II diabetes, and to explore the modifying role of weight category.

DESIGN

We conducted a cross-sectional analysis of the 2001-2002 visit for the Rancho Bernardo Study, Filipino Women's Health Study, and Health Assessment Study of African American Women.

SETTING AND PARTICIPANTS

Participants were 392 community-dwelling older women (mean age = 64) free of clinical cardiovascular disease.

MAIN OUTCOME MEASURE

The main outcome was prevalence of type II diabetes, defined as use of anti-diabetes medication, fasting plasma glucose ≥ 126 mg/dL, and/or OGTT ≥ 200 mg/dL.

RESULTS

Adjusting for demographics, hypertension, estrogen use, lipids, smoking, physical activity, visceral fat area, and height, a greater muscle-to-total abdominal area ratio (MAR) was associated with lower odds of diabetes [OR = 0.63 per standard deviation, 95% CI (0.43-0.92), p = .02]. Higher visceral fat was associated with greater odds of diabetes in fully adjusted models including total muscle area [OR = 1.48, 95% CI (1.09, 2.01), p = .01]. Associations between MAR and diabetes were stronger for normal weight (BMI 18.5-24.9; OR = 0.32) than overweight/obese women (BMI ≥ 25, OR = 0.71, p-for-interaction = 0.046). Associations with visceral fat did not differ by BMI (p-for-interaction = 0.71).

CONCLUSIONS

In older women, abdominal muscle area is inversely associated with type II diabetes independent of visceral adiposity, particularly for normal weight women.

Sedentary behavior and prevalent diabetes in Non-Latino Whites, Non-Latino Blacks and Latinos: findings from the National Health Interview Survey

BACKGROUND

Sedentary behavior is associated with type II diabetes, though little is known about prevalence of this behavior across racial/ethnic groups or how it may contribute to disparities in diabetes prevalence. In this study, we examined the association between sedentary behavior and diabetes in a diverse data set, and explored whether differences in sedentary behavior across racial/ethnic groups could contribute to disparities in diabetes.

METHODS

Participants were 27 141 adults from the 2010 US National Health Interview Survey. Logistic regression was used to assess associations between self-reported, non-occupational sitting time, race/ethnicity and physician diagnosis of type II diabetes.

RESULTS

In fully adjusted models, each hour of daily sitting was associated with 4% increased odds of diabetes (P < 0.01). Odds of diabetes were nearly double in Latinos (odds ratio [OR] = 1.83, confidence interval [CI] = 1.59-2.13) and Blacks (OR = 1.83, CI = 1.59-2.11) after adjusting for demographics and lifestyle factors. However, Blacks reported only slightly more sitting than Whites, and Latinos reported significantly less. Further adjustment for sitting hours in multivariate models did not attenuate disparities and slightly increased odds for Latinos (OR = 2.03, CI = 1.74-2.36).

CONCLUSIONS

Sitting appears to be an independent risk factor for diabetes across racial/ethnic groups, though it does not appear to account for disparities in diabetes.

Associations of physical activity and sedentary behavior with regional fat deposition

INTRODUCTION

Increased sedentary behavior predicts greater cardiovascular morbidity and mortality and does so independently of physical activity (PA). This association is only partially explained by body mass index (BMI) and overall body fat, suggesting mechanisms besides general increased adiposity. The purpose of this study was to explore associations of self-reported leisure PA and sitting time with regional fat depositions and abdominal muscle among community-dwelling older adults.

METHODS

Participants were 539 diverse adults (mean age = 65 yr) who completed a study visit in 2001-2002. Areas of pericardial, intrathoracic, subcutaneous, visceral, and intermuscular fat, as well as abdominal muscle, were measured using computed tomography. Leisure PA and sitting hours were entered simultaneously into multivariate regression models to determine associations with muscle and fat areas.

RESULTS

After adjusting for demographics, smoking, diabetes, hypertension, triglycerides, and cholesterol, greater PA was associated with less intrathoracic, visceral, subcutaneous, and intermuscular fat (for all P < 0.05), while greater sedentary time was associated with greater pericardial and intrathoracic fat (for both P < 0.05). After further adjusting for BMI, each hour of weekly PA was associated with 1.85 cm less visceral fat (P < 0.01) but was not associated with other fat depositions. Conversely, each hour of daily sitting was associated with 2.39 cm more pericardial fat (P < 0.05) but was not associated with any other fat depositions. There were no associations with abdominal muscle area. Adjusting for common inflammatory markers had little effect. Associations between fat and PA were stronger for men.

CONCLUSIONS

Sitting and PA have distinct associations with regional fat deposition in older adults. The association between sitting and pericardial fat could partially explain the link between sitting and coronary heart disease.

Physical Activity in Latino Men and Women

Latinos report less leisure time physical activity (PA) than non–Latino Whites and suffer disproportionately from diseases related to sedentary lifestyle, yet remain underserved and understudied. Gaining a better understanding of PA behavior in Latinos is critical to intervene on this significant public health issue. This article discusses the growing literature on the facilitators and barriers of PA in Latino men and women and reviews recent interventions to promote activity. Apart from acculturation influences, facilitators of PA in Latinos are similar to those of non–Latino Whites, with most research focusing on self-efficacy and social support. Barriers for Latinas, however, are more culturally distinct, such as a focus on caregiving and cultural standards for body shape. Barriers unique to Latino men largely have not been studied. Researchers have adopted a variety of approaches to increase PA, including using promotores and incorporating culturally appropriate activities, and have had mixed success. However, the community and randomized controlled trials almost exclusively included only women. Studies reviewed here suggest that interventions should target culturally specific barriers beyond language to successfully increase PA in Latinos and highlight a need for formative research and design of interventions for Latino men.

The Seamos Saludables study: A randomized controlled physical activity trial of Latinas

BACKGROUND

Latinas in the U.S. are less physically active than non-Latino white women and also report higher levels of diabetes, obesity, and other conditions related to inactivity. Interventions are needed to address disparities in this high-risk group.

PURPOSE

To evaluate the efficacy of a culturally adapted, Spanish-language, individually tailored, computer expert system-driven physical activity print-based intervention for adult Latinas.

DESIGN

RCT.

SETTING/PARTICIPANTS

Participants were 266 inactive adult Latinas who participated between 2009 and 2012.

INTERVENTION

Participants were randomized to one of two treatment arms: a 6-month tailored physical activity intervention condition or wellness contact control. For both conditions, print materials were delivered by mail.

MAIN OUTCOME MEASURES

The main outcome measure was change in weekly moderate-to-vigorous physical activity (MVPA) measured by the 7-Day Physical Activity Recall interview, which was administered at baseline and post-intervention (6 months). Participants also wore accelerometers for a week at baseline and follow-up. Analyses were conducted in 2013.

RESULTS

Increases in minutes/week of MVPA measured by the 7-Day PAR were significantly greater in the intervention group compared to the control group (mean difference=41.36, SE=7.93, p<0.01). This difference was corroborated by accelerometer readings (rho=0.44, p<0.01). Further, results indicate that intervention participants had greater increases in self-efficacy, cognitive processes, and behavioral processes at 3 months compared to control paricipants (p's<0.05).

CONCLUSIONS

The tailored Spanish-language intervention was effective in increasing MVPA among predominantly low-income, less-acculturated Latinas. Such print-based interventions are poised for widespread dissemination, and thus may help address health disparities.

Electron acceleration in the heart of the Van Allen radiation belts

The Van Allen radiation belts contain ultrarelativistic electrons trapped in Earth's magnetic field. Since their discovery in 1958, a fundamental unanswered question has been how electrons can be accelerated to such high energies. Two classes of processes have been proposed: transport and acceleration of electrons from a source population located outside the radiation belts (radial acceleration) or acceleration of lower-energy electrons to relativistic energies in situ in the heart of the radiation belts (local acceleration). We report measurements from NASA's Van Allen Radiation Belt Storm Probes that clearly distinguish between the two types of acceleration. The observed radial profiles of phase space density are characteristic of local acceleration in the heart of the radiation belts and are inconsistent with a predominantly radial acceleration process.

Physical activity in Latinas: social and environmental influences

Latinas are the largest, fastest growing female ethnic minority group in the USA, and also report the lowest levels of physical activity. Following the framework of the social ecological model, this review examines unique social and environmental factors that influence physical activity in Latinas. Research shows that Latinas receive little social support for activity despite having large, close-knit social networks. Interventions incorporating social support components are generally efficacious. Latinas also face many environmental barriers, including crime, heat, traffic, lack of facilities and a fear of immigration enforcement, and there have been few attempts to address environmental barriers in Latino communities. Successful future interventions will need to consider unique social and environmental barriers affecting Latinas, and help Latinas learn to incorporate social networks into physical activity participation.

Controlled aggregation of superparamagnetic iron oxide nanoparticles for the development of molecular magnetic resonance imaging probes

A method for synthesizing superparamagnetic iron oxide (SPIO) multi-nanoparticle aggregates as molecular magnetic resonance imaging (MRI) contrast agents is described. The approach utilizes organic acid/base interactions in the colloid to induce highly controllable nanoparticle aggregation. Monodisperse aggregates with diameters as large as 100 nm are synthesized by manipulating the interfacial surface chemistry of the SPIO nanoparticles in tetrahydrofuran solvent. Subsequent phospholipid micelle encapsulation yields micellar multi-SPIO (mmSPIO) aggregates with enhanced T(2) relaxivity (368.0 s(-1) mmol(-1) Fe) as compared to micellar single particle SPIO (302.0 s(-1) mmol(-1) Fe). mmSPIO conjugated to anti-CA125 monoclonal antibodies were incubated with ovarian carcinoma cell lines to demonstrate targeted in vitro molecular MRI, resulting in a 66% shortening in T(2) time for CA125 positive NIH:OVCAR-3 cells and a less than 3% change in T(2) time for CA125 negative SK-OV-3 cells. The controllable aggregation of mmSPIO shows potential for the development of molecular MRI contrast agents with optimal sizes for specific diagnostic imaging applications.

[Dogs and health. A review of documented connections]

Companion dogs are widespread in western countries, and scientific studies have proved that dogs have a number of positive effects on human health and well-being. Studies have shown reduced systolic blood pressure in dog owners compared to non-owners, as well as lowered concentrations of plasma triglycerides and cholesterol. Studies have also shown improved survival rates following myocardial infarction in dog owners compared to non-owners. Companion dogs are used systematically in "animal assisted therapy" in various institutions and hospitals, both as specific treatment of a medical condition and to improve well-being in certain groups of patients. The reasons for the positive effects of dogs on human health are not clearly identified. The attachment between people and their pets ("the human-animal bond") seems to have important physiological and psychological effects. Companion dogs have been shown to increase physical activity and social contact, which may also influence human health.

[Physician's role in certification for sick leave]]

The aim of the study was to analyse general practitioners' decisions when certifying patients as sick. The study was conducted among 38 general practitioners in Bergen, Norway, during two weeks in March 1990. The need for certification of sickness was considered for 328 patients. Among these 91% were certified as sick and 9% were not found to be incapable of work. If the patients took the first initiative for certification, 95% received a certificate, while 84% were certified sick when the doctors took the first initiative (p < 0.001). When no objective signs, symptoms or findings were registered by the general practitioners, the patients took the first initiative for sickness certification in 85% and the doctor in 15% (p = 0.001) of the cases. The study indicates that the patients are a stronger controlling element than the general practitioners in the process of certification of sickness.

Effect of testosterone on atherogenesis in cholesterol-fed rabbits with similar plasma cholesterol levels

The aim was to examine the effect of testosterone on atherogenesis in cholesterol-fed, castrated male rabbits not mediated via different plasma cholesterol levels. The rabbits in the testosterone group (n = 19) and in the placebo group (n = 17) were injected intramuscularly twice weekly for 17 weeks with 25 mg testosterone enantate and placebo, respectively, reaching plasma testosterone levels of 50-150 nmol/l in the testosterone group. No effect of testosterone on liver function or body weight was detected, but at week 15 mean blood pressure was 75 +/- 2 mmHg (mean +/- S.E.) in the testosterone group compared with 69 +/- 2 mmHg in the placebo group (P < 0.05). To reduce variation in plasma cholesterol between the two groups, the amount of cholesterol fed to each rabbit was adjusted on the basis of weekly determinations of plasma cholesterol; the mean plasma cholesterol levels during the 17 weeks were 20.9 +/- 1.0 and 20.4 +/- 0.9 mmol/l for the placebo and testosterone groups. In the intima-inner medias of the aortic arch, the thoracic and the abdominal aorta there were no consistent significant differences in aortic cholesterol content, expressed either as nmol/cm2 or nmol/mg protein, between the two groups. However, the aortic cholesterol content tended to be lower in the testosterone group than in the placebo group. These findings suggest that in cholesterol-fed, castrated male rabbits, testosterone does not promote atherogenesis by an effect directly on the arterial wall.

Protective HLA-DR phenotypes in rheumatoid arthritis

In a study of HLA-DR phenotypes in patients with rheumatoid arthritis (RA) and controls from the Saskatoon area and in Newfoundland, we found that certain phenotypes occurred more frequently in the patients than in healthy controls in both populations ("increased risk phenotypes"). The reverse was also true: certain phenotypes were reduced or excluded from patients with RA compared with controls. Three increased risk phenotypes with twice the expected frequencies or more were HLA-DR1,DR4; DR4 and DR4,DR5. Four "protective" phenotypes with half or less the expected frequencies were HLA-DR1, DR5; DR2; DR2,DR3 and DR3,DR7. We speculate that at least for the DR3,DR7 phenotype, the protective effect may be due to a hybrid DQw2 molecule.