Comparison of methods to estimate body fat in growth hormone deficient adults.

• All of the presently used methods for in-vivo determination of body composition have inherent methodological errors and depend on various assumptions. We have therefore compared several different methods used to measure body fat in adult GH deficiency during GH treatment.Comparison of body composition data from a two-phase trial with an initial placebo-controlled, double-blind 6-month period, followed by open treatment with GH until all patients had received GH for 12 months.Twenty-five patients with known GH deficiency entered the study. Baseline examinations were complete in 23 patients, and 22 patients (16 males, 6 females) completed all examinations after treatment.Body fat calculated from total body potassium (TBK) by whole-body 40K counting, total body water (TBW) by tritium dilution, total body nitrogen (TBN) by neutron activation, and bioelectric impedance (BIA) measurements were compared to body fat determinations by dual-energy X-ray absorptiometry (DEXA) in two-compartment and multicompartment body composition models.At baseline, DEXA fat mass agreed well at group level with measurements based on TBW or TBK alone, in a four-compartment model based on TBK and TBW, and a multicompartment model based on bone mineral (by DEXA), TBN and TBW. Body fat by BIA agreed less well. After 12 months of GH treatment, body fat decreased by all methods used. This decrease was smaller by DEXA than by the other methods. The four-compartment model based on TBK and TBW, and TBW alone, showed the best agreement with changes in DEXA fat.All methods showed a decrease of body fat with GH treatment, but variation between methods was considerable.

Subject headings

MEDICIN OCH HÄLSOVETENSKAP  -- Klinisk medicin -- Endokrinologi och diabetes (hsv//swe)

MEDICAL AND HEALTH SCIENCES  -- Clinical Medicine -- Endocrinology and Diabetes (hsv//eng)

MEDICIN OCH HÄLSOVETENSKAP  -- Medicinsk bioteknologi -- Biomedicinsk laboratorievetenskap/teknologi (hsv//swe)

MEDICAL AND HEALTH SCIENCES  -- Medical Biotechnology -- Biomedical Laboratory Science/Technology (hsv//eng)

Keyword

Absorptiometry

Photon

Adipose Tissue

anatomy & histology

Adult

Body Composition

Body Water

chemistry

Electric Impedance

Female

Growth Hormone

deficiency

therapeutic use

Humans

Male

Middle Aged

Models

Biological

Neutron Activation Analysis

Nitrogen

analysis

Potassium

analysis

Potassium Radioisotopes

Time Factors

Whole-Body Counting

Publication and Content Type

ref (subject category)

art (subject category)