Clinical trial NCT01055626: New Body Mass Index (BMI) Cut-offs for the Diagnosis of Obesity and Comorbidities
Official title: Usefulness of the Determination of Body Composition for Establishing New Cut-offs for the Diagnosis and Follow-up of Obesity and Comorbidities
Study type: OBSERVATIONAL
Overall status: UNKNOWN
Conditions: Obesity
Overweight
Diabetes Mellitus, Type 2
Keywords: Body mass index
Body fat
Obesity
Overweight
Diabetes Mellitus, Type 2
Air displacement plethysmography
Lead sponsor: Clinica Universidad de Navarra, Universidad de Navarra
Sponsor class: OTHER
First posted: 2010-01-25
Enrollment: 6000
Sex: ALL
Minimum age (years): 18
Maximum age (years): 80
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: yes
Observational model: COHORT
Time perspective: CROSS_SECTIONAL
Sampling method: NON_PROBABILITY_SAMPLE
Study population: Caucasian subjects able to come to Clinica Universidad de Navarra, Pamplona, Spain.

Patients visiting the Departments of Endocrinology and Surgery of the University Clinic of Navarra for weight loss treatment as well as hospital and University staff undergoing an annual routine health check-up .

Brief summary: Obesity is a serious medical problem because it increases the risk of cardiovascular disease (CVD), type 2 diabetes mellitus, and certain forms of cancer. The definition of obesity is based on an excess of body fat, not of BMI. However, BMI is the reference used to establish a graded classification of weight relative to height. Although BMI is widely used as a simple surrogate measure of body fat and has been shown to correlate closely with adiposity, it would be more appropriate to determine body fat percentage and to use this value for classification purposes. The present study contemplates the determination of the per cent body fat with the aim of establishing new diagnostic and therapeutic criteria according to the associated comorbidities.

Detailed description: The prevalence of overweight and obesity has increased alarmingly in the last decades. Obesity is a serious medical problem because it increases the risk of hypertension, type 2 diabetes mellitus, coronary heart disease, sleep-breathing disorders, and certain forms of cancer. Obesity is defined medically as a state of increased adipose tissue of sufficient magnitude to produce adverse health consequences. The definition of obesity is based on an excess of body fat, not of BMI. However, BMI is the reference used to establish a graded classification of weight relative to height. Although BMI is widely used as a simple surrogate measure of body fat and has been shown to correlate closely with adiposity, it would be more appropriate to determine body fat percentage and to use this value for classification purposes. The present study contemplates the determination of the per cent body fat (by air displacement plethysmography) in more than 5,000 subjects representing the whole BMI range, with the aim of establishing new diagnostic and therapeutic criteria according to the associated comorbidities. The specific objectives are: a) To know the body fat percentage means for normal weight, overweight and obesity for both sexes. b) To know the body fat percentage means for normal weight, overweight and obesity for the different age ranges. c) To analyse the relationship between body fat percentage and BMI values in order to detect misclassified individuals. d) To establish new cut-offs for body fat percentage and the normality ranges according to its relationship with cardiovascular risk factors that could be useful in the diagnosis and therapy of obesity.

Eligibility criteria: Inclusion Criteria:

* BMI \>18.5
* No major organ disease unrelated to excess body weight

Exclusion Criteria:

* Pregnancy/lactation
* History of eating disorder or major psychiatric illness

Primary outcomes:
measure: Differences in body fat
timeFrame: Baseline
Secondary outcomes:
measure: Differences in glycemic control
timeFrame: Baseline
measure: Differences in cardiovascular risk factors
timeFrame: Baseline
Other outcomes:
Locations:
city: Pamplona
country: Spain
facility: Clinica Universidad de Navarra - University of Navarra
state: Navarra
city: Pamplona
country: Spain
facility: Clinica Universidad de Navarra
Study officials:
affiliation: Clínica Universidad de Navarra
name: Gema Frühbeck, MD, PhD
role: PRINCIPAL_INVESTIGATOR
References:
citation: Gomez-Ambrosi J, Silva C, Galofre JC, Escalada J, Santos S, Gil MJ, Valenti V, Rotellar F, Ramirez B, Salvador J, Fruhbeck G. Body adiposity and type 2 diabetes: increased risk with a high body fat percentage even having a normal BMI. Obesity (Silver Spring). 2011 Jul;19(7):1439-44. doi: 10.1038/oby.2011.36. Epub 2011 Mar 10.
citation: Gomez-Ambrosi J, Silva C, Galofre JC, Escalada J, Santos S, Millan D, Vila N, Ibanez P, Gil MJ, Valenti V, Rotellar F, Ramirez B, Salvador J, Fruhbeck G. Body mass index classification misses subjects with increased cardiometabolic risk factors related to elevated adiposity. Int J Obes (Lond). 2012 Feb;36(2):286-94. doi: 10.1038/ijo.2011.100. Epub 2011 May 17.
citation: Gomez-Ambrosi J, Gonzalez-Crespo I, Catalan V, Rodriguez A, Moncada R, Valenti V, Romero S, Ramirez B, Silva C, Gil MJ, Salvador J, Benito A, Colina I, Fruhbeck G. Clinical usefulness of abdominal bioimpedance (ViScan) in the determination of visceral fat and its application in the diagnosis and management of obesity and its comorbidities. Clin Nutr. 2018 Apr;37(2):580-589. doi: 10.1016/j.clnu.2017.01.010. Epub 2017 Jan 28.
citation: Gomez-Ambrosi J, Silva C, Catalan V, Rodriguez A, Galofre JC, Escalada J, Valenti V, Rotellar F, Romero S, Ramirez B, Salvador J, Fruhbeck G. Clinical usefulness of a new equation for estimating body fat. Diabetes Care. 2012 Feb;35(2):383-8. doi: 10.2337/dc11-1334. Epub 2011 Dec 16.