The Relationship between Body Composition and Clinical Parameters in Chronic Obstructive Pulmonary Disease
Chaicharn Pothirat MD, FCCP*, Warawut Chaiwong BS*, Nittaya Phetsuk BS*, Chalerm Liwsrisakun MD*, Chaiwat Bumroongkit MD*, Athavudh Deesomchok MD*, Theerakorn Theerakittikul MD*, Atikun Limsukon MD*
Affiliation : * Division of Pulmonary, Critical Care and Allergy, Department of Internal Medicine, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand
Objective : Identify a correlation between body mass index (BMI) and fat-free mass index (FFMI) to clinical parameters in
chronic obstructive pulmonary disease.
Material and Method: The cross-sectional study was conducted at a single visit involving stable chronic obstructive
pulmonary disease (COPD) patients at the outpatient chest clinic of the Chiang Mai University Hospital, Thailand. Eligible
patients were evaluated for BMI, FFMI, lung function, modified medical research council (mMRC) dyspnea score, COPD
assessment test (CAT) score, and number of acute exacerbation (AE) in the past year. The correlations of FFMI and BMI
with other parameters were determined using Pearson correlation coefficient analysis. Body composition was categorized
into four groups, normal, semi-starvation, muscle atrophy/sarcopenia, and cachexia based on BMI and FFMI. Statistical
significance was accepted at p-value <0.05.
Results : One hundred twenty one stable COPD patients met study inclusion criteria. The FFMI showed a strong correlation
with BMI (r = 0.792, p<0.001). The FFMI, but not BMI, was significantly correlated with mMRC, precentage of predicted
forced expiratory volume in first second (FEV1), and CAT score (r = -0.315, 0.214, and -0.278, respectively). Body composition
was categorized into four groups: normal body composition (n = 62, 51.2%), semi-starvation (n = 4, 3.3%), sarcopenia/
muscular atrophy (n = 12, 9.9%), and cachexia (n = 43, 35.5%).
Conclusion : FFMI, but not BMI, was significantly correlated with dyspnea severity, lung function, and quality of life. Body
composition category assignment is a useful clinical tool.
Keywords : Chronic obstructive pulmonary disease, Fat-free mass index, Body mass index, Quality of life, Correlation
