Research

Active Studies:

Working Title: Sedentary Time & Aging Mortality and Physical Function (STAR) Program
Name: Sedentary Behaviour Interrupted: Acute, medium and long-term effects on biomarkers of healthy aging, physical function and mortality
Funder: NIA
Project Dates: 07/01/2017 – 05/31/2022

Purpose:
1. Provide scientific evidence on associations between interrupting sitting and key indicators of healthy aging using biological, behavioral, epidemiological and computational approaches, rigorous trial study designs, and accurate, objective measures of SB and PA.
2. Define acute-, medium-, and long-term health effects of interrupting sitting by both standing and PA breaks in postmenopausal women at risk for chronic diseases.
3. Identify novel biological outcomes impacted by interrupting sitting, including glucose regulation, physical functioning, emotional and cognitive functioning and disease-moderating mechanisms (endothelial function and mitochondrial function).
4. More accurately classify sitting, standing, sit-to-stand transitions and PA breaks to better assess their relationships with healthy aging by use of novel, objective device-based measurement, innovative machine-learning methodologies, and new statistical approaches.
5. Explore the moderating effects of age on the relationships between interrupting SB and healthy aging outcomes.

Project 1: Lab Trial
N=86
Aim: To investigate whether acute interruptions of prolonged sitting improve metabolism and endothelial function associated with healthy aging.
Measures: Screening visit, 4 study visits: blood draws/BP every 30 min, standardized nutrition, FMD 2x/visit, devices

Project 2: Intervention Trial
N=592
Aim: To investigate the effects of increased standing, additional brief sit-to-stand transitions and PA breaks on glucose regulation
Measures: Baseline, 12 weeks: blood draws, vitals, NIRS, devices, surveys

Project 3: Machine Learning
N= >6,000
Aim: To apply novel, machine learned behavior based classification methods to define new SB variables using exisiting accelerometer data in cohort of postmenopausal women from OPACH ancillary study

Working Title: AVE - AHA Sedentary Study (active)
Name: Randomized control trial to reduce sitting time in postmenopausal Latina women at increased risk for heart disease
Funder: American Heart Association
Project Dates: 4/1/2016 – 3/31/2020

Purpose:  To test whether a new intervention will reduce sitting time over 3 months in post-menopausal Latina women at increased risk for heart disease. We will also see if blood pressure, depressive symptoms and weight change with this intervention. The intervention will help Latinas understand when and where they sit most and help them to break up the sitting. They will wear special devices that help track sitting and a health educator will help them set goals to plan standing in their day. Of 250 women, half will receive the standing intervention and half will receive information about heart health, not related to standing. We will also collect blood samples from participants and test whether reducing sitting affects important biological processes measured in the blood.

Arms:

  • 12 week reduced sitting arm
  • 12 week heart healthy lifestyle arm

Population: 250 postmenopausal Latina women at risk for heart disease
Measurement timepoints: BL + 3 months
Measures: ActivPAL, Blood outcomes (mitochondrial functioning, Epigenetic DNA modification profile, Epigenetic microRNA biomarkers, Vascular/endothelial functioning biomarkers, glucoregularory and lipid metabolism biomarkers) BP, Depressive symptoms, Quality of Life, Anthropometrics, demographics, SPPB

Specific Aims:

  • Investigate the 3-month effect of the intervention to impact the primary behavioral outcomes of sitting, standing and stepping time assessed objectively by a thigh worn inclinometer (ActivPAL) in Latinas at risk for heart disease.
  • Investigate the 3-month effect of the intervention to impact the secondary health outcomes of blood pressure, depressive symptoms, and anthropometrics.
  • Explore the psychosocial & environmental mediators & moderators of changes in sitting time.
  • Compare 3-month changes associated with 25%-reduced sitting time intervention vs. healthy control lifestyle advice conditions for:
    • DNA methylation
    • miRNA expression
    • Mitochondrial function metabolites
  • Compare 3-month changes for:
    • Endothelial function
    • Glucose and lipid metabolism
  • Among a subsample of 100 PM women, we will Conduct in vitro validation studies of candidate miRNAs as SB outcome mechanistic transducers

Working title: PEP4PA (active)
Name: Peer Empowerment Program for Physical Activity in Low Income & Minority Seniors
Funder: NHLBI
Project Dates: 12/01/14 – 11/30/2019 (open to recruitment)

Purpose: PEP4PA (Peer Empowerment Program 4 Physical Activity) is a multilevel intervention aimed at increasing physical activity levels in a population of low income and ethnically diverse older adults.  It will be delivered in centers by trained older adults. Participants will work towards a daily increase of 2000 steps per day through self-paced incidental walking, peer led group walks, and attendance at existing center PA classes. They will also work on projects to increase opportunities to be physically active at their center or in the surrounding neighborhood.

Arms:

  • Physical activity intervention
  • Re-randomized at 18 months to 1) receive continued funding, or 2) no continued funding
  • Usual care control

Population: 408 older adults over the age of 50 attending 12 community centers in SD County
Measurement timepoints: BL, 6, 12, 18, 24 months
Measures: waist accelerometer ( BL, 12, 24 mos), wrist accelerometer and GPS (all timepoints), survey, physical and cognitive assessments, BP, medication use, sleep, 6 minute walk test, cost-effectivenes

Aims:
1. The efficacy of PEP4PA (Peer Empowerment Program 4 Physical Activity) to reduce disparities in PA by increasing the percentage of participants achieving 150 minutes of PA per week at 6 and 12 months. Hypothesis: Participants in PEP4PA will significantly increase PA minutes in moderate intensity (measured objectively by accelerometry) to a greater extent than older adults receiving usual care (e.g. normal PA programing) in control centers and a greater percent will meet NHANES criteria for weekly PA.
2. The efficacy of PEP4PA to improve physical functioning, blood pressure (BP), depressive symptoms and quality of life. Hypothesis: Participants in PEP4PA will significantly increase their physical functioning (measured objectively by the short physical performance battery and 6 minute walk test), decrease their systolic BP (mmHg) and reporting of depressive symptoms, and improve their quality of life scores (measured at baseline, 6 & 12 months) to a greater extent than older adults in control centers.
3. Assess the incremental cost effectiveness ratio (ICER) of PEP4PA in terms of cost per MET hour and cost per QALY compared to usual programming in the control centers at 12 months.
4. Evaluate the impact of PEP4PA on secondary outcomes such as sedentary time and sleep quality (measured by accelerometry), cognitive/executive functioning, and walking routes (from GPS) at 12 months.
Exploratory aims: 5. Examine individual, interpersonal, organizational, and environmental factors that affect implementation & behavior change. 6. Assess the efficacy, effectiveness and ICER of PEP4PA at 24 months

Working title: PQA4  (active)
Full name: GPS exposure to healthy environments and relations with biomarkers of cancer risk
Funder: NCI
Project Dates: 09/01/13-08/31/17 (open to recruitment)

Purpose: Where people spend their time during the day may be related to their risk of getting cancer. Previous studies have only looked at places near to home. This project will assess behaviors in different locations across the day and relate exposure to different environments to biological outcomes such as insulin resistance.
Population: 700 men and women, aged 35-80 years of age
50% Hispanic
4 quadrants of Neighborhood selection: high or low PA environment x high or low nutrition environment
Measurement timepoints: 14 days
Measures: Waist accelerometer, wrist accelerometer, GPS, Sensecam (subsample- 50), Survey, BP, diet recall, blood and urine

Aims:
Primary Aim:
Investigate whether GPS based Dynamic GIS measures of exposure to PA supportive environments will have a stronger association with breast and colon cancer risk factors – insulin resistance and inflammation (e.g. CRP, IL-6, HOMA-IR) – than Static GIS measures of access.
Secondary Aim:
Investigate whether Dynamic GPS-GIS measures of exposure to predominantly high fat and sugar food environments have a stronger association with insulin resistance and inflammation than Static GIS measures.
Exploratory aim:
In a subsample of participants (N=50), we propose to explore whether portable SenseCam measures of social interactions & social behaviors from person view images are more strongly related to breast and colon cancer risk factors than self-reported social environment measures.

All of the following are completed:

Working Title: Sedentary Behavior Lab Pilot
Name: Sedentary Behavior Interrupted - A Pilot Study of Acute Interventions on Prolonged Sitting
Funder: UC San Diego Department of Family Medicine and Public Health and its Women’s Health Center of Excellence
Project Dates: Enrollment from March – April 2016

Purpose:
Conditions: Participants completed all 4 study conditions. All conditions included a 1 hour lead-in steady state period, a variable 5-hr sitting condition protocol, and a per-protocol bathroom break at study period time 2.5 hr
A) Control. Participants sat quietly for 5 hr and were instructed to minimize excessive movement (i.e., fidgeting) while sitting. This condition was used as the control condition for comparison in statistical analyses.
B) Participants completed 2 min of standing every 20 min throughout the 5-hr protocol period. This condition amounted to 15 sit-to-stand transitions, 30 min of standing time, and a 10% reduction in sitting time compared to the 5-hr sitting control condition.
C) Participants completed 2 min of light walking every hour throughout the 5-hr active protocol period. Participants were escorted in their walk in the clinic hallways and encouraged to walk at a comfortable, purposeful pace. This condition amounted to 5 sit-to-stand transitions, 10 min total walking time, and a 3.3% reduction in sitting time compared to the 5-hr sitting control condition.
D) Participants completed 10 min of standing every hour throughout the 5-hr active protocol period. Participants stood keeping their hips, legs and feet still on a modestly padded mat. They were permitted small, brief stretching movements of their upper body without lowering their head below waist level, and they had access to a standing desk to facilitate their continued work/reading/game activity while standing. This condition amounted to 5 sit-to-stand transitions, 50 min of standing time, and a 17% reduction in sitting time compared to the 5-hr control condition.
Population: 10 postmenopausal, sedentary women
Measures: Endothelial function (flow-mediated dilation), blood pressure, heart rate, plasma glucose, plasma insulin, feasibility and acceptability measures

Aims: Using a randomized, controlled crossover study design, assess the feasibility and metabolic and endothelial function outcomes of an acute bout of prolonged sitting ± standing or walking interruptions using targeted metabolic and endothelial function biomarker analyses.  

 

Working title: MIPARC
Name: Multilevel Intervention for Physical Activity in Retirement Communities
Funder: NHLBI
Project Dates: 4/2010 – 3/31/14 (closed)

Purpose: Physical activity not only helps keep healthy older adults living independently, but has positive effects for those with chronic disease or disabilities and is associated with recovery from functional limitations in older age.5,6  Physical activity is associated with improved quality of life, reduced depression, reduced risk of falls and improved cognitive functioning.7-13  The public health impact of reducing inactivity in this population, even if physical activity is below recommendations, could be great.14

Arms:

  • Physical activity intervention
  • Successful Aging control

Population: 351 residents over the age of 65 living in Continuing Care Retirement Communities (CCRC) in SD County
n=307 participants, n=44 peer leaders
Measurement timepoints: BL, 3, 6, 9, 12 months
Measures: waist accelerometer, GPS, survey, physical and cognitive assessments, BP

Aims:
Primary: : In a cluster randomized controlled field trial, assess the efficacy of a tailored 6 month multilevel PA intervention to increase minutes of PA among older adults in retirement communities.
Secondary aims: To assess the efficacy of a tailored 6 month multilevel PA intervention to improve blood pressure, physical functioning and quality of life among older adults in retirement communities.
GIS R21
Purpose: Develop and validate novel GIS-based total daily environmental exposure measures along routes and around locations identified by GPS traces from participants at baseline and relate them to baseline health behaviors most likely to be influenced by the built environment, e.g. PA, sedentary behavior and healthy eating.

Working title: iWatch
Name: Validating machine-learned classifiers of sedentary behavior & physical activity
Funder: NCI
Project Dates: 07/12/12 - 4/30/16 (closed)

Purpose: This study uses small sensors to objectively measure when people sit or do physical activity, and we will use sophisticated computational techniques to summarize these movement patterns.
Population: 210 males and females between 6-85 years.
Measurement timepoints: 7 days
Measures: Waist accelerometer, wrist accelerometer, GPS, Sensecam, Survey

Aims:
1. To validate machine-learned algorithms to classify patterns of accelerometer data to better discriminate types of sedentary behaviors and physical activity
2. To develop machine learned algorithms to classify behaviors using images collected by the SenseCam.
3: Evaluate the need for age-specific machine-learned algorithms to better discriminate types of SB and PA.
4: Quantify behavioral misclassification that occurs using cut-points vs. a machine-learned classifier of SB in our existing data sets, as well as historic data sets (e.g., NHANES).
5: Incorporate the new validated machine-learned behavioral classifiers into our existing NIH-funded web-based application, PALMS.

Working title: MENU
Name: Diet Composition and Genetics: Effects on Weight, Inflammation and Biomarkers (Kerr, CoI)
Funder: NCI
Project Dates: 07/2011 – 07/2016 (closed to recruitment/data collection complete)

Purpose: Excess adiposity is a risk factor for postmenopausal breast cancer and a major risk factor for recurrence in both pre- and postmenopausal breast cancer, and the biological mechanisms are not fully understood. women assigned to three study arms: a higher-carbohydrate (65% energy), lower-fat (20% energy) diet; a lower-carbohydrate (45% energy), higher-monounsaturated fat (35% energy) diet; or a walnut-rich, lower-carbohydrate (45%), higher-fat (35% of energy) diet in a 12-month cognitive-behavioral weight loss program consisting of group sessions and individualized counseling. 
Population:
N=234 obese women, 21 and older, have initial BMI >27.0 kg/m2 and <40 kg/m2
Measurement timepoints: BL, 6, 12 months
Measures: Waist accelerometer, GPS, heart rate monitor, Survey, blood, diet recall

Aims:
1. To examine whether there is a differential weight loss response to different dietary macronutrient composition (higher carbohydrate and lower fat versus lower carbohydrate and higher monounsaturated fat [MUFA] or lower carbohydrate and walnut-rich higher fat diets) in a weight loss intervention in healthy obese women, depending on insulin resistance status. 
2. To examine whether there is a differential response (depending on insulin resistance status) to different dietary macronutrient composition in a weight loss intervention in the hormonal factors and markers of inflammation that may link obesity to breast cancer mortality.  Specific markers to be examined are insulin, homeostasis model assessment (HOMA), SHBG, estrogens, C-reactive protein (CRP), interleukin-6 (IL-6), tumor necrosis factor α (TNF-α), and as a marker for gene expression, IL-6 and TNF-α gene methylation.
3. To identify nutrient-gene interactions that contribute to differential response of cytokines to weight loss and diet composition associated with polymorphisms in IL-6 and TNF-α genes.

Secondary aim will be to:
Examine the relationship between exposure to obesogenic environments (assessed by GPS and GIS) and physical activity (PA), sedentary behavior (SB) and BMI.

Working title: RfH
Name: Reach for Health
Funder: NCI
Project Dates: 07/2011 – 07/2016 (data collection ongoing)

Purpose:
This study is a 6-month randomized controlled trial of metformin, a lifestyle intervention, or both, on biomarkers for breast cancer recurrence and survival among a sample of 340 postmenopausal, overweight/obese breast cancer survivors. 
Population:
N=340, postmenopausal, overweight/obese breast cancer survivors.  
Measurement time points: BL, 6 months
Measures: Waist accelerometer, GPS, ht/wt, Survey, diet recall, blood

Aims: Participants will be randomized in equal numbers to (1) placebo, (2) metformin, (3) lifestyle intervention and placebo, or (4) lifestyle intervention and metformin.  The lifestyle intervention will focus on reducing energy intake and increasing energy expenditure to achieve a 7% weight reduction.  Biomarkers will be assayed in fasting blood samples collected at baseline and 6 months.  We hypothesize that among overweight/obese postmenopausal breast cancer survivors, metformin and lifestyle interventions will improve biomarker levels and that the combination of those interventions will have an additive effect. 

Working title: xTREC
Name:  Objective integrated measures of physical activity, sedentary behavior, sleep, and the built environment
Funder: NCI
Project Dates: 6/1/12 to 11/13

Purpose:
Population:
Total N: 372 women

  • UCSD –breast cancer survivors (n=75) age 55-75 years
  • WUSTL- Healthy women, (n=76),  21-65 yr
  • Harvard - Healthy women, (n=92), 45-75 yr
  • UPenn- Breast cancer survivors, (n=120), 21-75 yr

Measurement timepoints: 7 days
Measures: Waist + Hip accelerometer, GPS, Built environment ,GIS-derived variables, surveys. Sleep log, sedentary behavior

Aims:
Primary  - evaluate the convergent validity of objective and self-reported data on PA, SB, and sleep collected from multiple samples living in different geographic regions of the US.
Secondary

  • 2. examine the feasibility and validity of a wrist mounted accelerometer to contemporaneously measure PA, SB, and sleep;
  • examine the feasibility of deploying and using GPS in an ethnically diverse adult cohort to develop GIS-matched measures of the built environment relevant to PA, SB, and sleep; and
  • describe the inter- and independent patterns (e.g., volume, type) of objectively measured PA, SB, and sleep among individuals with different cancer status (survivor vs. healthy), and investigate whether these patterns are related to characteristics of the built environment (e.g., neighborhood walkability) and time spent in different locations (e.g., in neighborhood vs. out of neighborhood).

                                                                                       

Working title: SB Pilot
Name:  Optimizing sedentary behavior interventions to affect acute physiological changes
Funder: Department of Family and Preventive Medicine
Project Dates: 7/13 – 7/14

Purpose: We propose a pilot study to assess the feasibility, acceptability and preliminary efficacy of two interventions targeting sedentary behavior.  Since it is currently unknown what component of sedentary behavior exposure presents the greatest risk to health, we propose separate interventions to reduce overall sedentary time and to promote breaks in sedentary time.

Arms:

  • Reduce sitting time by 2 hours
  • Increase the number of standing breaks

Population: N=30, men and women, aged 50-70, who sit for ≥8 hours per day, working and non-working
Measurement timepoints: BL, 1, 2, 3 weeks
Measures: ActivPal, surveys

Aims:
Primary aim: To determine the acceptability and feasibility of selected personal, social and environmental strategies to reduce overall sitting time and increase the number of times participants stand up in a day.
Secondary aim: To assess whether existing and new measurement approaches can detect specific changes in sedentary behavior.
Exploratory aim: To establish whether specified intervention strategies were efficacious in reducing sedentary behavior and whether intervention effects were specific to the targeted sedentary behavior construct (e.g. decreased overall sitting time or increased number of breaks in sitting).

Working title: DIAL
Name: Training data for a machine learning project using two cohorts of women at risk for breast cancer.
Funder: NCI
Project Dates: 06/01/12 - 05/31/13 (closed to recruitment)

Purpose: Train and validate machine-learned algorithms to classify patterns of accelerometer and GPS data to better discriminate types of sedentary behavior (SB) and physical activity (PA) in participants with similar disease risk to the TREC Menu and Reach for Health cohorts.
Population:
N=40 women who did not meet the strict eligibility criteria of the MENU or RfH studies or declined to participate in the longer intervention trial, but still represent the overall study population.

  • post-menopausal, overweight or obese,  breast cancer survivors (RfH, n=20)
  • obese women, 21+ years, at risk for developing breast cancer (MENU, n=20)

Measurement timepoints:  7 day wear
Measures: Waist and hip accelerometer, GPS, Sensecam, Heart rate monitor, survey, BP, Height, weight, sleep, sedentary

Aims:
Train and validate machine-learned algorithms to classify patterns of accelerometer and GPS data to better discriminate types of sedentary behavior (SB) and physical activity (PA) in participants with similar disease risk to the TREC Menu and Reach for Health cohorts.

Working title: MIPASC pilot
Name:  Multilevel Intervention for Physical Activity in Senior Centers
Funder: Department of Family and Preventive Medicine
Project Dates:  07/2011 – 07/2012 (closed to recruitment)

Purpose: The purpose of the pilot was to adapt and translate an existing multilevel intervention in retirement communities (MIPARC) into Spanish, to make cultural adaptations, and to pilot test key components of both the Successful Aging and Physical Activity program in high and low income older adults attending senior centers in San Diego County.  Received 4 educational sessions.
Population: N=85 older adults aged 48-94 attending one of the 3 Senior Centers included in study
30% Hispanic, 30% African American
Measurement timepoints: 7 days at BL
Measures: Waist accelerometer, GPS, Survey, TUG, Trails A/B, BP

Aims:
Assess the feasibility of delivering and assessing a 6-week multilevel intervention on Successful Aging.

Working title: SAGE (Stein) pilot
Name:  SAGE Daily Behavior Study
Funder: Stein Institute for Research on Aging
Project Dates: 06/2012 -09/2013 (closed to recruitment)

Purpose: Collect pilot data using the SenseCam to support future grant proposals on sedentary behavior and outdoor physical activity. improve our understanding of accelerometer measures in older adults and inform our analysis of the MIPARC intervention trial.

Population:
N = 40 participants from the Stein SAGE study,  selected to vary in physical functioning based on the SF-36 measure used in the SAGE survey, with 10 participants from each of four decades 60-100.             Participants were a subsample of community-dwelling older adults, 24 men and 16 women, ranging in age from 63 to 99 (mean 80.97 ± 10.76), recruited from UCSD’s Successful Aging Evaluation (SAGE) . Participants with the following characteristics were excluded: 1) Residing in a nursing home or other assisted housing, or who required daily skilled nursing care; 2) Diagnosed with dementia; 3) Diagnosed with a terminal disease or receiving hospice care; and 4) Planning to move outside San Diego County within the next three years. Participants provided informed, written consent, and  were quota sampled by age deciles and physical/cognitive functions scores creating 4 age-decile groups with approximately half lower-functioning.
Measurement timepoints: 7 day weartime
Measures: Waist accelerometer (2 of the same?), GPS, Sensecam, Survey, Neurocom, force plate, physical functioning, cognitive functioning, Ht/wt

Aims: This was a cross-sectional pilot study of an elderly population, evenly age-distributed across four age deciles, focused on the feasibility of gathering objective data using wearable devices in independently-living older adults.

  • Improve assessments of sedentary behavior and outdoor physical activity and validate appropriate GPS and accelerometer algorithms to define these behaviors.
  • Relate improved measures of sedentary behavior and outdoor activity with health outcomes assessed in the SAGE study and measured in the laboratory.
  • Validate self report measures of sedentary behavior and other activities employed in the SAGE survey.

Working title: SenseCam Cycling Study
Name:  PALMS Project Pilot IV
Funder: NCI (under PALMS grant #5U01 CA130771)
Project Dates: Summer 2011

Purpose: Allow for the refinement of the PALMS platform with free-living validation data. Test the usability of SenseCam in a field setting.
Population: N=40, healthy, working adults or students from the UCSD Commuter Cycling Network
Measurement timepoints:   3-5 day (We had 2 waves of recruitment because we only had the devices for 2 weeks. One wave had about 3 days of wear and the other had 5 days of wear.)
Measures: Waist accelerometers (GT3X+ and ActiCal), GPS, Sensecam, Survey

Working title: Sleep Validation Study (Xavier Soler, PI)
Name:  Validation of physical activity accelerometers for measuring sleep
Funder: TREC funds (?)
Project Dates: 02/01/14 – 05/2014

Purpose: Assess the validity of Activgraph waist and wrist accelerometers for sleep assessment, as compared to the PSG.
Population:
N=22?
Male, female, 50-75 years of age, healthy or mild pulmonary disease (COPD, asthma), no sleep disorder
Measurement timepoints: 1 night
Measures: Waist accelerometer, wrist accelerometer, polysonography sleep monitor, surveys
Total Sleep Time (TST), sleep latency and fragmentation assessment, compare waist versus wrist

Aims:

SNQLS
TREC 4 - SUNI
Jay Mendoza Bicycling study

Other:

  • PALMS Field testing and validation (CYCLING) – IRB# 111274
  • PALMS 007 – GPS on Fe en Accion cohort
  • PALMS 007 - Dia con Dia (IRB# 121378)
  • PALMS A tool for geospatial analysis of physical activity IRB 140432
  • Somali women – Kate Murray

 

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