Body mass index and prognosis in patients hospitalized with acute exacerbation of chronic obstructive pulmonary disease

Abstract

BackgroundNutritional status, weight loss and cachexia have important prognostic implications in patients with chronic obstructive pulmonary disease (COPD). Body mass index (BMI) has been implicated in COPD risk assessment, but information is mostly limited to composite scores or to patients with stable disease. We aimed to analyse the association between BMI and mortality in acute exacerbation of COPD.MethodsThis retrospective survey included 968 patients hospitalized due to acute exacerbation of COPD at the University Clinic Golnik from February 2002 to June 2007. Vital status was ascertained with Central Population Registry, and database was censored on November 1, 2008.ResultsMedian BMI was 25.08 kg/m2 (interquartile range, 21.55–29.05 kg/m2) and 210 patients (22%) had BMI < 21 kg/m2. During median follow-up of 3.26 years (1.79–4.76 years), 430 patients (44%) died. Lowest mortality was found for BMI 25.09–29.05 kg/m2. When divided per BMI decile, mortality was lowest for BMI 25.09–26.56 kg/m2 (33%). In univariate analysis, BMI per quartile and BMI per unit increase were predictive for all-cause mortality. In an adjusted model, BMI per 1 kg/m2 unit increase was associated with 5% less chance of death (hazard ratio 0.95, 95% confidence interval 0.93–0.97).ConclusionsLow BMI < 21 kg/m2 is frequent in patients hospitalized due to acute exacerbation of COPD. Higher BMI was independently predictive of better long-term survival. A better outcome in obese patients compared to normal weight is in contrast to primary prevention data but concurs with observations of an obesity paradox in other cardiovascular diseases.

Nutritional assessment and therapy in COPD: a European Respiratory Society statement

“…In patients with moderate to severe airflow obstruction, a BMI ,25 kg?m -2 was consistently associated with increased mortality risk relative to overweight and even obese patients [14][15][16]. This prognostic advantage of increased BMI in COPD, also referred to as the ''obesity paradox'', could be related to the direct effect of adipose tissue on lung mechanics (e.g.…”

Chronic Obstructive Pulmonary Disease: Official diagnosis and treatment guidelines of the Czech Pneumological and Phthisiological Society; a novel phenotypic approach to COPD with patient-oriented care

“…Residual volume (RV) is typically increased at rest in COPD patients and additionally dynamic hyperinflation occurs during physical activities, which is associated with increased expiratory effort 13,14 . Systemic consequences are often found in cardiovascular, musculoskeletal and other systems [15][16][17][18] . COPD can be considered a proven pre-cancerous condition 19 .…”

“…Subjects with 2 or more episodes of AE during the last year are termed frequent exacerbators [45][46][47] . A small pro- 17,41,48 . An important phenotype is COPD overlapping bronchial asthma that is characterised by the presence of either 2 major criteria, or 1 major and at least 2 minor criteria showing a persistent combination of clinical presentation that is typical for both conditions 3,8,42,[49][50][51] .…”

Evaluation of nutritional status and nutritional therapy in chronic obstructive pulmonary disease

“…В этом профиле риска использована адап тированная Всемирной организацией здравоохра Метаболические фенотипы и профили нутритивного риска при ХОБЛ В крупных популяционных исследованиях последних лет показано, что у некурящих общая частота леталь ного исхода, стандартизованная по возрасту, была ми нимальной при ИМТ 22,5-24,9 и 20-25 кг / м 2 [8, 9]. У больных со среднетяжелой и тяжелой бронхиаль ной обструкцией ИМТ < 25 кг / м 2 был стойко связан с более высоким риском летальности по срав нению с больными с избыточной МТ и даже с ожи рением [14][15][16]. Прогностические преимущества по вышения ИМТ у больных ХОБЛ, также называемые «парадоксом ожирения», могут быть связаны с не посредственным влиянием жировой ткани на меха нику дыхания (например, на относительное сниже ние статических легочных объемов у больных ХОБЛ с ожирением [17]).…”