Evaluation of anthropometric methods for fat mass measurement in chronic obstructive pulmonary disease patients.

Background: Chronic obstructive pulmonary disease (COPD) is a chronic inflammatory lung disease that causes obstructed airflow from the lungs. The obesity is a global problem, which is set to increase over time. Chronic obstructive lung disease is the third-leading cause of death globally, and both obesity and diet appear to play roles in its pathophysiology (e.g., role in the development of obstructive sleep apnoea and obesity hypoventilation syndrome). However, the effects of obesity on the respiratory system are often underappreciated.

Objective: The objective of this study was to compare three anthropometric methods to evaluate of fat mass in COPD patients.

Material and methods: Three anthropometric methods of evaluation fat mass in a group of 60 patients with COPD were compared. To the measurement of fat mass were used: (1) Dual Energy X-ray Absorptiometry method (DEXA), specifically by DEXA densitometer QDR Discovery Wi (S/N 80227) with additional software (Body Composition Analysis); (2) four-frequency bioelectrical impedance analysis (BIA) device Bodystat Quadscan 4000 (Bodystat Ltd, British Isles); (3) skin folds measurement (SFM) with caliper (Harpenden Lange Skinfold Caliper, Cambridge Scientific Industries, Inc. Cambridge, Maryland). The measured values were statistically processed and evaluated in a statistical program Statistica Cz. version 7.1 and Microsoft Office Excel 2010 (Los Angeles, CA, USA). Differences among anthropometric methods of measurement fat mass were tested with one-way analysis of variance (ANOVA). The data were presented as mean ± standard deviation (SD).

Results: DEXA method, generally accepted for assessing body composition, showed an average value of 22.48 ±11.32 kg of fat mass, which corresponds in percentage terms to the value of 29.62±9.28. BIA method for the parameter fat mass in the monitored group of COPD patients was found the mean value 25.08±10.14 kg (in percentages 30.85±8.15). An average value 28.50±8.08% of fat mass, was determined from the skinfolds measurements (SFM) and subsequent calculations. When comparing these methods (DEXA, BIA and SFM) used to determine body composition, a statistically insignificant difference was found (P >0.05).

Conclusions: In this study a good correlation between three anthropometric methods (DEXA, BIA, SFM) for measuring fat mass in patients with COPD and statistically insignificant differences between them were observed. To better define changes in the nutritional status of patients with COPD using anthropometric methods over time, further studies are needed that also monitor the consequences of clinical status, rehabilitation, and nutritional treatment.