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Predicting Adherence to a Heart-Healthy Diet in Lean and Obese Individuals

Is Non-Adherence Unique to Weight-Loss? Predictors of Adherence to a Heart-Healthy Diet in Lean vs. Obese Individuals

Background:

- Sticking to a diet plan can be difficult, but is important for many different health reasons. Some people seem to have a harder time following and sticking to a diet plan than others. It is not clear whether people of different weights (lean or obese) might have differences in the way they adhere to diet plans. Researchers want to study three different groups of people based on their body mass index (BMI), which measures people based on their weight and height. The study will place the participants on a 6-week diet and see how well they follow the diet. The information from this study may help develop better weight-loss plans and healthy diet ideas.

Objectives:

  • To understand what factors affect adherence to a diet plan.
  • To collect information for future studies that may improve people's ability to stick to diets.

Eligibility:

- Individuals at least 18 years of age who are lean (BMI between 18.5 and 25) or obese (BMI greater than 30).

Design:

  • Participants will be screened with a physical exam and medical history. Blood and urine samples will be collected. They will have a full-body scan to measure fat and muscle. They will also answer questions on eating behaviors, mood, and desire to change eating patterns.
  • Participants will be separated into three groups. Each group will have a different diet. The lean group will have a heart-healthy diet designed to maintain the same weight. One of the obese groups will also have a heart-healthy diet designed to maintain the same weight. The other obese group will have a heart-healthy weight loss diet. In all groups, all food will be provided by the study doctors. Participants should not eat any food other than that provided for the study.
  • Everyone will start with a 1-week food testing period to find the right number of calories for each group. After this first week, participants will attend one diet counseling session per week and will be contacted randomly once a week to check on the foods they have had in the past 24 hours. Participants will complete daily food diaries on paper as well as daily food records using a smart phone.
  • Participants will come to the clinic twice a week to pick up the diet food. On one of those days, they will also have their counseling session.
  • The study will last for 6 weeks. At the final study visit, participants will repeat the tests from the screening study.

Přehled studie

Detailní popis

Adherence, or "sticking to your diet" is important for successful initial weight loss and keeping off the weight over the long term (1). While early behavioral and dietary adherence have been associated with greater weight loss, sticking to a diet plan is difficult. It is not clear if adherence to any diet plan (even one which does not produce weight loss) is hard or whether people who are overweight have more difficulty with adhering to diet plans compared to people who are relatively lean.

The main aim of this study is to evaluate dietary adherence in 3 groups of individuals participating in a 6-week heart-healthy dietary intervention program. Two groups [1 (BMI < 25 kg/m(2)) and 2. Obese (BMI greater than or equal to 30 kg/m(2))] will receive a heart-healthy diet designed to maintain their weight, and the third group [3. Obese] will be given a heart-healthy diet that is 35% less than their daily calorie needs to lose weight. Participants will attend one counseling session per week and will be contacted randomly 1x/week by study staff for completion of a 24-hour dietary recall. They will complete daily food diaries and daily records using smart-phones. Prior to starting the assigned heart-healthy dietary intervention, participants will complete questionnaires that include questions about how motivated they are to follow a diet, lose weight, and change eating patterns. These findings may help us understand what factors affect adherence, and help us design weight loss studies that improve people's ability to stick to diet interventions.

Typ studie

Intervenční

Zápis (Aktuální)

100

Fáze

  • Nelze použít

Kontakty a umístění

Tato část poskytuje kontaktní údaje pro ty, kteří studii provádějí, a informace o tom, kde se tato studie provádí.

Studijní místa

    • Arizona
      • Phoenix, Arizona, Spojené státy, 85014
        • NIDDK, Phoenix

Kritéria účasti

Výzkumníci hledají lidi, kteří odpovídají určitému popisu, kterému se říká kritéria způsobilosti. Některé příklady těchto kritérií jsou celkový zdravotní stav osoby nebo předchozí léčba.

Kritéria způsobilosti

Věk způsobilý ke studiu

18 let až 70 let (Dospělý, Starší dospělý)

Přijímá zdravé dobrovolníky

Ano

Pohlaví způsobilá ke studiu

Všechno

Popis

-INCLUSION CRITERIA:

  1. BMI

    • BMI greater than or equal to 30 kg/m(2) for the obese WMEN and UF groups but body weight less than 350 pounds to accommodate the DXA scanner
    • BMI less than or equal to 25 kg/m(2) (and BMI greater than or equal to 18.5 kg/m(2)) for the lean WMEN group
  2. Age greater than or equal to 18 years. Minors under the age of 18 will be excluded because growth and pubertal issues are significant parameters that could affect our outcomes and also because the time requirements of the study are such that they would interfere with school schedules. Participants must be healthy, as determined by medical history, physical examination, and laboratory tests.
  3. Weight stable (plus or minus 2 percent) for last 3 months

EXCLUSION CRITERIA:

Candidates will be screened by phone to exclude those with BMI greater than or equal to 26 kg/m(2) and BMI less than or equal to 29 kg/m(2), significant health problems, including cancer, hypertension, diabetes, current and past 3-month use of certain prescribed medications, especially those that could affect body weight, such as antidepressants and stimulants as well as smoking, or excess alcohol (greater than 3 drinks/d). Women must not be pregnant or lactating, and be at least 1 year postpartum. Candidates with a history of psychotic disorder or hospitalization for psychiatric illness within the past 1 year will not be eligible. They will need to be weight stable for the past 3 months (plus or minus 2 percent) and cannot be in treatment for obesity or currently receiving psychotherapy. Individuals who meet criteria according to the phone screen will be invited to come to the unit for a screening visit and their screening sheets are placed in a locked filing cabinet. Forms from potential volunteers who are ineligible are shredded.

Studijní plán

Tato část poskytuje podrobnosti o studijním plánu, včetně toho, jak je studie navržena a co studie měří.

Jak je studie koncipována?

Detaily designu

  • Primární účel: Léčba
  • Přidělení: Randomizované
  • Intervenční model: Paralelní přiřazení
  • Maskování: Žádné (otevřený štítek)

Zbraně a zásahy

Skupina účastníků / Arm
Intervence / Léčba
Experimentální: Obese underfeeding (UF)
Obese randomized to received a 35% calorie reduced diet
Heart healthy diet with 35% reduced calories
Ostatní jména:
  • UF
Experimentální: Obese weight maintaining (WMEN)
Randomized to receive a weight-maintaining diet
Heart healthy weight-maintaining diet
Ostatní jména:
  • WMEN
Experimentální: Lean weight maintaining (WMEN)
Normal weight individuals receiving a weight-maintaining energy needs diet
Heart healthy weight-maintaining diet
Ostatní jména:
  • WMEN

Co je měření studie?

Primární výstupní opatření

Měření výsledku
Popis opatření
Časové okno
Adherence Score
Časové okno: Average over 6 weeks
An adherence score is calculated each week by summing 7 measurements of adherence and dividing by 21, the maximum score, with range from 0 (no adherence) to 1 (perfectly adherent). For each of the 7 measures a higher score means better adherence: [1] Attendance (0-2), [2] Food diaries (0-3), [3] 24-hour food recall via interview (0-3), [4] computer survey (0-3), [5] 24-hour food recall via interview (0-3), [6] Ecological momentary assessment (0-6), and [7] On time arrival for session (0-1). The final score is calculated as the average of the six weekly scores.
Average over 6 weeks

Sekundární výstupní opatření

Měření výsledku
Popis opatření
Časové okno
Change in Weight From Baseline to 6 Weeks
Časové okno: 6 weeks
Weight loss from baseline, calculated as weight at 6 weeks - weight at baseline
6 weeks

Spolupracovníci a vyšetřovatelé

Zde najdete lidi a organizace zapojené do této studie.

Vyšetřovatelé

  • Vrchní vyšetřovatel: Marci Gluck, Ph.D., National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)

Publikace a užitečné odkazy

Osoba odpovědná za zadávání informací o studiu tyto publikace poskytuje dobrovolně. Mohou se týkat čehokoli, co souvisí se studiem.

Termíny studijních záznamů

Tato data sledují průběh záznamů studie a předkládání souhrnných výsledků na ClinicalTrials.gov. Záznamy ze studií a hlášené výsledky jsou před zveřejněním na veřejné webové stránce přezkoumány Národní lékařskou knihovnou (NLM), aby se ujistily, že splňují specifické standardy kontroly kvality.

Hlavní termíny studia

Začátek studia

31. května 2013

Primární dokončení (Aktuální)

22. května 2018

Dokončení studie (Aktuální)

22. května 2018

Termíny zápisu do studia

První předloženo

23. května 2013

První předloženo, které splnilo kritéria kontroly kvality

23. května 2013

První zveřejněno (Odhad)

24. května 2013

Aktualizace studijních záznamů

Poslední zveřejněná aktualizace (Aktuální)

15. srpna 2019

Odeslaná poslední aktualizace, která splnila kritéria kontroly kvality

23. července 2019

Naposledy ověřeno

22. května 2018

Více informací

Termíny související s touto studií

Další relevantní podmínky MeSH

Další identifikační čísla studie

  • 999913096
  • 13-DK-N096 (Jiný identifikátor: NIDDK/NIH)

Tyto informace byly beze změn načteny přímo z webu clinicaltrials.gov. Máte-li jakékoli požadavky na změnu, odstranění nebo aktualizaci podrobností studie, kontaktujte prosím register@clinicaltrials.gov. Jakmile bude změna implementována na clinicaltrials.gov, bude automaticky aktualizována i na našem webu .

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