Chest
Volume 128, Issue 4, October 2005, Pages 2108-2115
Journal home page for Chest

Clinical Investigations
Mid-Arm Muscle Area Is a Better Predictor of Mortality Than Body Mass Index in COPD

https://doi.org/10.1378/chest.128.4.2108Get rights and content

Background

A low body mass index (BMI) has been shown to be an independent indicator of poor prognosis in patients with COPD. However, some studies suggest that muscle mass depletion (MD) is the main factor responsible for the negative effects attributable to malnutrition.

Study objective

To evaluate the prognostic influence of MD estimated from anthropometric parameters.

Design and measurements

Mortality was studied in a prospective cohort of 96 male patients with COPD (average age, 69 ± 9 years; FEV1 percentage of predicted, 44 ± 18% [± SD]) followed up for 3 years, with an evaluation of the prognostic influence of the following anthropometric parameters: BMI, mid-arm muscle area (MAMA), and fat-free mass index. Other risk factors were also analyzed, such as age, comorbidity (Charlson index), basal dyspnea index, the St. George's Respiratory Questionnaire score, the number of hospital admissions in the year prior to nutritional evaluation, the number of hospital admissions in the year immediately after nutritional evaluation (Hpost), spirometry, and blood gases.

Results

In the multivariate study, Paco2 (p = 0.003; hazard ratio, 1.08), Hpost (p = 0.005, hazard ratio, 4.63), and a MAMA value less than or equal to percentile 25 of the reference value (p25) [p = 0.025; hazard ratio, 3.78] were found to be independent indicators of poor prognosis. Respiratory mortality after 12, 24, and 36 months in the patients with MAMA ≤ p25 was 12.1%, 31.4%, and 39.2%, respectively, vs 5.9%, 7.9%, and 13% in the group of patients without MD (p = 0.006). In normal-weight or overweight patients, MAMA ≤ p25 increased the risk of mortality 3.4-fold (p = 0.032).

Conclusions

MD is a better predictor of mortality than BMI in patients with COPD, fundamentally in normal-weight or overweight patients. The prognostic influence of MD can be estimated indirectly by determining the MAMA, an inexpensive, simple, and rapidly obtained anthropometric measure.

Section snippets

Subjects

A prospective study was made of a cohort of 114 patients with stable COPD. The patients were recruited in the last trimester of the year 2000, with a subsequent follow-up period of 3 years. The diagnosis of COPD was based on a current or previous smoking history (> 20 packs-year), clinical assessment, and pulmonary function testing.17 The postbronchodilator FEV1, expressed as a percentage of the theoretical value, was used to classify the patients according to Global Initiative for Chronic

Subject Characteristics

A total of 114 patients with a diagnosis of COPD were studied. Of these, 18 patients (15.8%) were excluded for different reasons: 7 patients (6.1%) with decompensated cor pulmonale, 3 patients (2.6%) with liver cirrhosis, 2 patients (1.7%) with neoplasms, 2 patients (1.7%) due to sustained oral corticosteroid use, 2 patients (1.7%) because of heart failure, 1 patient (0.9%) with chronic renal failure, and another patient (0.9%) due to malabsorption syndrome. A total of 96 patients were

Discussion

The present study confirms previous data on the effect of muscle mass on mortality in patients with COPD. In stable patients, MD is associated to an increased risk of death. In addition, as a remarkable finding, we show that the prognostic influence of muscle mass can be assessed by determining the MAMA, an inexpensive, simple, and rapidly obtained anthropometric measure. MAMA ≤ p25 was found to be a poor prognosis marker, exerting an influence in our series superior to that of other

References (40)

  • GroenewegenKH et al.

    Mortality and mortality-related factors after hospitalization for acute exacerbation of COPD

    Chest

    (2003)
  • LandboC et al.

    Prognostic value of nutritional status in chronic obstructive pulmonary disease

    Am J Respir Crit Care Med

    (1999)
  • Gray-DonaldK et al.

    Nutritional status and mortality in chronic obstructive pulmonary disease

    Am J Respir Crit Care Med

    (1996)
  • ScholsAMWJ et al.

    Weight loss is a reversible factor in the prognosis of chronic obstructive pulmonary disease

    Am J Respir Crit Care Med

    (1998)
  • PrescottE et al.

    Prognostic value of weight change in chronic obstructive pulmonary disease: results from the Copenhagen City Heart Study

    Eur Respir J

    (2002)
  • CelliBR et al.

    The body-mass index, airflow obstruction, dyspnea, and exercise capacity index in chronic obstructive pulmonary disease

    N Engl J Med

    (2004)
  • ScholsAMWJ et al.

    Prevalence and characteristics of nutritional depletion in patients with stable COPD eligible for pulmonary rehabilitation

    Am Rev Respir Dis

    (1993)
  • BernardS et al.

    Peripheral muscle weakness in patients with chronic obstructive pulmonary disease

    Am J Respir Crit Care Med

    (1998)
  • EngelenMPKJ et al.

    Nutritional depletion in relation to respiratory and peripheral skeletal muscle function in an outpatient population with chronic obstructive pulmonary disease

    Eur Respir J

    (1994)
  • BaarendsEM et al.

    Peak exercise response in relation to tissue depletion in patients with chronic obstructive pulmonary disease

    Eur Respir J

    (1997)
  • Cited by (0)

    Reproduction of this article is prohibited without written permission from the American College of Chest Physicians (www.chestjournal.org/misc/reprints.shtml).

    This work was performed at Hospital General de Requena, Unidad de Neumología, Servicio de Medicina Interna, Valencia, Spain.

    View full text