Ariane Jacob PhD(c)1,2,3, Catherine Laurin PhD1,2,4, Kim L Lavoie PhD1,2,3,5, Gregory ... quality of life (4-6), increased health care costs (7) and premature.
original arTicle
The impact of body mass index on inpatient- versus outpatient-treated chronic obstructive pulmonary disease exacerbations Ariane Jacob PhD(c)1,2,3, Catherine Laurin PhD1,2,4, Kim L Lavoie PhD1,2,3,5, Gregory Moullec PhD1,2,4, Maxine Boudreau PhD(c)1,2,3, Catherine Lemière MD2, Simon L Bacon PhD1,2,4,5 A Jacob, C Laurin, KL Lavoie, et al. The impact of body mass index on inpatient- versus outpatient-treated chronic obstructive pulmonary disease exacerbations. Can Respir J 2013;20(4):237-242. BACKgRound: Increased body weight has been associated with worse prognoses for many chronic diseases; however, this relationship is less clear in patients with chronic obstructive pulmonary disease (COPD), with underweight patients experiencing higher morbidity than normal or overweight patients. oBJECTIVE: To assess the impact of body mass index (BMI) on the risk for COPD exacerbations. METhods: The present study included 115 patients with stable COPD (53% women; mean [± SD] age 67±8 years). Height and weight were measured to calculate BMI. Patients were followed for a mean of 1.8±0.8 years to assess the prospective risk of inpatient-treated exacerbations and outpatienttreated exacerbations, all of which were verified by chart review. REsuLTs: Cox regression models revealed that underweight patients were at greater risk for inhospital-treated exacerbations (RR 2.93 [95% CI 1.27 to 6.76) relative to normal weight patients. However, overweight (RR 0.59 [95% CI 0.33 to 1.57) and obese (RR 0.99 [95% CI 0.53 to 1.86]) patients did not differ from normal weight patients. All analyses were adjusted for age, sex, length of diagnosis, smoking pack-years, forced expiratory volume in 1 s, and time between recruitment and last exacerbation. BMI did not influence the risk of out-of-hospital exacerbations. ConCLusIons: The present study showed that underweight patients were at greater risk for inhospital exacerbations. However, BMI did not appear to be a risk factor for out-of-hospital exacerbations. This suggests that the BMI-exacerbation link may differ according to the nature of the exacerbation, the mechanisms for which are not yet known. Key Words: Body mass index; Chronic obstructive pulmonary disease; Cohort studies; Disease progression; Exacerbations; Pulmonary disease
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hronic obstructive pulmonary disease (COPD) is the third leading cause of death in North America (1) and affects 210 million adults worldwide (2). The course of the disease is characterized by recurrent exacerbations (ie, significant symptom deterioration requiring additional therapy) (3), which are associated with decreased lung function (4), increased rates of hospitalization (4), deterioration in quality of life (4-6), increased health care costs (7) and premature mortality (5). Several risk factors for exacerbations have been identified (eg, cigarette smoking, decreased lung function [ie, forced expiratory volume in 1 s (FEV1)]), previous exacerbations (8) and a low body mass index (BMI) (5,9). Low BMI has been shown to be an important risk factor for inhospital-treated exacerbations in several studies. For example, two prospective studies showed that having a low BMI (
