Aging, Obesity
Conditions
Brief summary
Obese older adults will be randomized to participate in either healthy lifestyle intervention or behavioral diet and exercise intervention for one year. This study aims to determine the effects of Lifestyle intervention on bone microarchitecture, bone strength, bone material properties, and the mechanism behind it.
Detailed description
Previous studies had suggested that lifestyle therapy (diet plus exercise) resulting in weight loss in elderly population improves physical function, cardio metabolic risk factors, and cognition/quality of life, but a major complication is loss of BMD. The addition of exercise to diet-induced weight loss attenuated but did not eliminate weight-loss-induced reduction of BMD. Moreover, while long-term maintenance of weight loss and physical function was feasible, sustained lifestyle change led to continued loss of hip BMD, which might predict hip fractures. Although similar BMD loss with weight loss has been observed in younger populations, BMD loss in older adults might be of particular concern because of aggravation of age-related bone loss. Moreover, the belief that obesity protects against fractures has now been challenged by studies demonstrating that obesity is associated with poor bone quality and ankle and leg fractures.Because of previous lack of options to assess bone quality in vivo, there has been little or no scientific study of the possibility that lifestyle therapy in obese older adults improves bone quality. This study represents an unprecedented opportunity to prove the hypothesis that lifestyle therapy intervention improves bone quality and thus, may confer a protective rather than adverse effect on bone health. This will be the first randomized controlled trial (RCT) to comprehensively assess bone quality using novel techniques in response to lifestyle therapy in obese older adults, with major ramifications with regards to defining optimal treatment strategies for this increasingly high-risk older population.
Interventions
BEHAVIORALHealthy Lifestyle Intervention
Participants in the this group will receive group educational sessions that focus on diet, exercise, and social support once a month throughout the study. The sessions will provide an opportunity for participants to discuss issues related to living with obesity and aging.Participants will also attend regular scheduled clinic visits for assessment of outcomes.
BEHAVIORALLifestyle Intervention
The lifestyle modification will be achieved by group behavior therapy sessions designed to have older adults acquire positive weight-control skills/attitudes, and practice weight-maintenance skills.Participants will attend weekly group sessions (10-15 persons), which will last \ 75-90 minutes. Visit frequency will be decreased to every 2 wks. from 6 to 12 mos. to prevent treatment fatigue. A balanced diet will be prescribed to provide a deficit of 500-750 kcal/day from daily energy requirement. The exercise sessions are of \ 90 min duration (\ 15 min warm-up of flexibility exercise, followed by \ 30 min of aerobic exercise, and after a brief rest period, \ 30 min of resistance training, and finally \ 15 min balance exercise) conducted three times weekly supervised at our exercise facility for one year. Aerobic exercises consist of treadmill, stationary cycling, and stair climbing.
Sponsors
National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
Michael E. DeBakey VA Medical Center
Biomedical Research Institute of New Mexico
Baylor College of Medicine
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
65 Years to 85 Years
Healthy volunteers
No
Inclusion criteria
* Age 65 - 85 years • BMI 30 kg/m2 or more• Stable body weight (±2 kg) during the past 6 months • Sedentary (regular exercise \<1 h/wk. or \<2 x/wk. for the last 6 months) • Willing to provide informed consent
Exclusion criteria
* Failure to provide informed consent. * Any major chronic diseases, or any condition that would interfere with exercise or dietary restriction, in which exercise or dietary restrictions are contraindicated, or that would interfere with interpretation of results * Cardiopulmonary disease (e.g. recent myocardial infarction, unstable angina, stroke) or unstable disease (e.g., New York Heart Class III or IV congestive heart failure, severe pulmonary disease requiring steroid pills or the use of supplemental oxygen ) that would contraindicate exercise or dietary restriction * Severe orthopedic (e.g. awaiting joint replacement) and/or neuromuscular (e.g. multiple sclerosis, amyotrophic lateral sclerosis, active rheumatoid arthritis) disease or impairments that would contraindicate participation in exercise * Other significant co-morbid disease that would impair ability to participate in the exercise-based intervention (e.g. renal failure on hemodialysis, severe psychiatric disorder \[e.g. bipolar, schizophrenia\], excess alcohol use \[more than14 drinks per week\]) * Severe visual or hearing impairments that would interfere with following directions * Significant cognitive impairment, defined as a known diagnosis of dementia or positive screening test for dementia using the Mini-Mental State Exam score less than 24) * Uncontrolled hypertension (BP\>160/90 mm Hg) * History of malignancy during the past 5 years (except non-melanoma skin cancers) * Current use of bone acting drugs (e.g. use of estrogen, or androgen containing compound, raloxifene, calcitonin, parathyroid hormone during the past year or bisphosphonates during the last two years) * Osteoporosis (T-score -2.5 and below on hip or spine scan) or history of fragility fractures - Diabetes mellitus requiring insulin for treatment or with a fasting blood glucose of \>140 mg/dl, and/or HbA1c \>8.5% (Those excluded from the study because of fasting blood glucose of \>140 mg/dl or HbA1c\>8.5% will be referred to their primary care provider for follow-up and appropriate treatment). * Terminal illness with life expectancy less than 12 months, as determined by a physician * Use of any drugs or natural products designed to induce weight loss within past three months. * Positive exercise stress test for ischemia
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Change in cortical thickness | Change from baseline at 12 months | Assessed by using high-resolution peripheral computed tomography (HR-pQCT) |
| Change in femoral bone strength | Change from baseline at 12 months | Assessed by using finite element analyses (FEA) of quantitative computed tomography (QCT) |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Change in physical performance test | Change from baseline at 12 months | assessed by using the objective physical performance test |
| Change in gait speed | Change from baseline at 12 months | as measured by completing the time to walk a certain distance |
| Change in handgrip strength | Change from baseline at 12 months | Measured by hydraulic hand dynamometer |
| Change in trabecular thickness | Change from baseline at 12 months | Assessed by using HR-pQCT |
| Change in areal bone mineral density (BMD) | Change from baseline at 12 months | Assessed by using dual-energy x-ray absorptiometry |
| Change in trabecular number | Change from baseline at 12 month | Assessed by using HR-pQCT |
| Change in total volumetric BMD | Change from baseline at 12 months | Assessed by using HR-pQCT |
| Change in cortical volumetric BMD | Change from baseline at 12 months | Assessed by using HR-pQCT |
| Change in trabecular volumetric BMD | Change from baseline at 12 months | Assessed by using HR-pQCT |
| Change in stiffness | Change from baseline at 12 months | Assessed by using HR-pQCT |
| Change in trabecular separation | Change from baseline at 12 months | Assessed by using HR-pQCT |
| Change in micro-finite element analyses strength | Change from baseline at 12 months | Assessed by using HR-pQCT |
| Change in cortical porosity | Change from baseline at 12 months | Assessed by using HR-pQCT |
| Change in general quality of life | Change from baseline at 12 months | Assessed by using the Short Form-36 questionnaire |
| Change in obesity specific quality of life | Change from baseline at 12 months | Assessed by using the Impact of weight on quality of life short form (IWQOL-Lite) questionnaire |
| Change in mood | Change from baseline at 12 months | Assessed by using a mood scale questionnaire |
| Change in composite cognitive z-score | Change from baseline at 12 months | Using cognitive instrument testing |
| Change in cardio metabolic risk factors | Change from baseline at 12 months | Assessed by measuring metabolic syndrome components |
| Change in word list fluency | Change from baseline at 12 months | Assessed by using cognitive instrument testing |
| Change in Ray Auditory verbal learning test | Change from baseline at 12 months | Assessed by using cognitive instrument testing |
| Change in blood pressure | Change from baseline at 12 months | Assessed by usingSphygmomanometer |
| Change in biochemical marker for bone turnover and bone metabolism | Change from baseline at 12 months | Assessed by using enzyme linked immunosorbent assay and radioimmunoassay |
| Change in central volumetric BMD | Change from baseline at 12 months | Assessed by using CT scan at the spine and hip |
| Change in waist circumference | Change from baseline at 12 months | Assessed by using tape measurement |
| Change in lean mass | Change from baseline at 12 months | Assessed by using dual-energy x-ray absorptiometry |
| Change in fat mass | Change from baseline at 12 months | Assessed by using dual-energy x-ray absorptiometry |
| Change in visceral fat | Change from baseline at 12 months | Assessed by using dual-energy x-ray absorptiometry |
| Change in physical activity using accelerometer | Change from baseline at 12 months | Assessed by using an accelerometer |
| Change in body weight | Change from baseline at 12 months | Assessed by using weighing scale |
| Change in sclerostin | Change from baseline at 12 months | Assessed by using enzyme linked immunoassay |
| Change in wnt signaling pathways | Change from baseline at 12 months | Assessed by measurements of circulating levels of Wnt 5a and Sfrp5 |
| Change in total body mass | Change from baseline at 12 months | Assessed byusing dual energy x-ray absorptiometry |
| Change in hormones | Change from baseline at 12 months | Assessed by usingenzyme link immunoassay |
| Change in thigh mass | Change from baseline at 12 months | Assessed by using CT scan |
| Change in bone material strength | Change from baseline at 12 months | Assessed by using microindentation testing |
| Change in adipocytokines | Change from baseline at 12 months | Assessed by using enzyme linked immunoassay |
| Change in cortical trabecular BMD | Change from baseline at 12 months | Assessed by using QCT Pro software |
| Change in aerobic capacity | Change from baseline at 12 months | Assessed by using indirect calorimetry during graded treadmill test |
| Change in circulating cytokines | Change from baseline at 12 months | Assessed by using enzyme linked immunoassay |
| Change in lower extremity strength | Change from baseline at 12 months | Assessed by using a Biodex dynamometer |
Countries
United States
Outcome results
None listed