Effects of Time of Sleep Restriction in Obesity

Effect os Sleep Restriction on Control of Food Intake and Metabolism of Obese Subjects

The purpose of this study is to determine the effect of different time of sleep restriction on control of food intake and metabolism of obese and normal subjects.

Study Overview

• Status: Completed
• Conditions: Obesity; Appetite Regulation; Eating; Sleep Restriction

Detailed Description

The reduction of sleep time has now become a common habit, driven by the demands and opportunities of modern society. Some studies have suggested that sleep restriction would be an important factor in predisposing to obesity. However studies of sleep restriction in obese individuals have not yet been conducted. Still, the time of sleep restriction varies greatly between studies, making it difficult to compare results.

The investigators aim to recruit 20 young adults, 10 obese and 10 normal weight individuals. The study will be conducted as a randomized, crossover study with three conditions. Each participant will be subjected to reduction of the beginning of sleep (from 3-7h), reduction of the end of sleep (from 23-3h), and normal sleep (from 23-7h), in random order, for three consecutive nights.

In each condition, subjects will stay for 4 days in the laboratory. Three control meals will be offered. Visual analogue scales will be applied before and after each meal to assess hunger and appetite for different food categories. Blood samples will be collected hourly during 24 hours.

• Study Type: Observational
• Enrollment (Actual): 20

Contacts and Locations

Study Locations

• Brazil
  • Sao Paulo, Brazil, 04020-060
    • Centro de Estudos em Psicobiologia e Exercicio (CEPE)

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 20 years to 35 years (Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: Male

• Sampling Method: Non-Probability Sample

Study Population

primary care clinic, community sample, residents of the city of Sao Paulo

Description

Inclusion Criteria:

• obese (BMI>30) and normal weight (BMI between 19 and 24,9)
• regular time of sleep between 6.5 and 8 hours

Exclusion Criteria:

• self-reported sleep problems (Pittsburgh Sleep Quality Index score >5);
• Obstructive sleep apnea (AHI > 5 in polysomnography)
• night work;
• variable sleep habits or habitual daytime naps;
• regular physical exercise (>3 hours/week);
• excessive intake of alcohol (>7 drinks/week);
• excessive intake of caffeine (>300 mg/day);
• smoking;
• substance abuse;
• use of prescription medications or over-the-counter drugs affecting sleep or metabolism;
• chronic diseases (e.g. cancer, asthma, back pain, thyroid disease, heart disease, diabetes, etc.)
• history of neurological, medical or sleep disorders;
• trans-meridian travelling the last month;
• chronotype: extreme morning or extreme evening
• unable to comply with the protocol.

Study Plan

How is the study designed?

Design Details

• Observational Models: Case-Crossover
• Time Perspectives: Cross-Sectional

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort
Obesity; BMI > 30kg/m2
Normal weight; BMI between 19 and 24,9kg/m2

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Appetite regulating hormones and stress hormones	Hormones are sampled from blood	Measured every hour over the course of 24 hours on day 3

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Hunger and satiety	Hunger and saciety are measured using visual analogue scales before and after breakfast, lunch and dinner meal	Measured every 4 hour over the course of 12 hours on day 2 and 3
Food intake	The meal will be weighted before and after the breakfast, lunch and dinner. Energy and nutrient intake are assessed from the amount of the meal consumed.	measured each meal

Collaborators and Investigators

• Sponsor: Federal University of São Paulo
• Collaborators: Associacao Fundo de Incentivo a Psicofarmcologia; Centro de Estudos em Sonolência e Acidentes
• Investigators: Principal Investigator: Marco Tulio de Mello, PHD, Federal University of São Paulo

Study record dates

Study Major Dates

• Study Start: February 1, 2009
• Primary Completion (Actual): September 1, 2011
• Study Completion (Actual): June 1, 2012

Study Registration Dates

• First Submitted: December 13, 2010
• First Submitted That Met QC Criteria: December 13, 2010
• First Posted (Estimate): December 14, 2010

Study Record Updates

• Last Update Posted (Estimate): August 18, 2014
• Last Update Submitted That Met QC Criteria: August 14, 2014
• Last Verified: August 1, 2014

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Overnutrition; Nutrition Disorders; Overweight; Body Weight; Obesity
• Other Study ID Numbers: CEPE18; FAPESP2008/09565-2 (Other Grant/Funding Number: FAPESP)