Lessard Andréa, Turcotte Hélène, Cormier Yvon, Boulet Louis-Philippe
Centre de Recherche, Hôpital Laval, Institut de cardiologie et de pneumologie de l'Université Laval, Québec, QC, Canada.
Centre de Recherche, Hôpital Laval, Institut de cardiologie et de pneumologie de l'Université Laval, Québec, QC, Canada.
Chest. 2008 Aug;134(2):317-323. doi: 10.1378/chest.07-2959. Epub 2008 Jul 18.
Obesity is associated with an increased prevalence of asthma, especially in women, and appears to be more severe in the obese. This study aimed to determine if obese subjects have a specific asthma phenotype.
Forty-four consecutive obese subjects (body mass index [BMI] > or = 30 kg/m(2)) and 44 consecutive nonobese subjects (BMI < 25 kg/m(2)), all with asthma, completed an asthma control questionnaire, and underwent methacholine challenge with symptom perception scores, and sputum induction for differential cell count. BMI, waist circumference, and waist-to-hip ratio also were measured.
Despite similar expiratory flows, bronchodilator response, airway responsiveness to methacholine, and symptom perception scores, asthma control was poorer in obese subjects than in nonobese subjects (p = 0.005). Total lung capacity (p = 0.01), expiratory reserve volume (p < 0.0001), functional residual capacity (p < 0.0001), and residual volume (p = 0.006) were lower in obese subjects than in nonobese subjects. Induced-sputum eosinophil and neutrophil counts were similar in both groups, although there was an inverse correlation between sputum eosinophils and waist circumference and a trend for a similar relationship for BMI. Blood serum C-reactive protein (p = 0.009) and fibrinogen (p = 0.0004) levels were higher in obese subjects than in nonobese subjects.
Obese people with asthma had poorer asthma control than nonobese asthmatics despite similar symptoms perception. Bronchial and systemic inflammatory characteristics and the specific pattern of pulmonary function changes suggest a different phenotype of asthma in these subjects.
Clinicaltrials.gov Identifier: NCT00532363 and NCT00532831.
肥胖与哮喘患病率增加相关，尤其是在女性中，并且在肥胖者中似乎更为严重。本研究旨在确定肥胖受试者是否具有特定的哮喘表型。
44名连续的肥胖受试者（体重指数[BMI]≥30kg/m²）和44名连续的非肥胖受试者（BMI<25kg/m²），均患有哮喘，完成哮喘控制问卷，并接受乙酰甲胆碱激发试验并记录症状感知评分，以及诱导痰进行细胞分类计数。还测量了BMI、腰围和腰臀比。
尽管呼气流量、支气管扩张剂反应、气道对乙酰甲胆碱的反应性和症状感知评分相似，但肥胖受试者的哮喘控制比非肥胖受试者差（p = 0.005）。肥胖受试者的肺总量（p = 0.01）、呼气储备量（p<0.0001）、功能残气量（p<0.0001）和残气量（p = 0.006）低于非肥胖受试者。两组诱导痰嗜酸性粒细胞和中性粒细胞计数相似，尽管痰嗜酸性粒细胞与腰围呈负相关，且BMI也有类似关系的趋势。肥胖受试者的血清C反应蛋白（p = 0.009）和纤维蛋白原（p = 0.0004）水平高于非肥胖受试者。
尽管症状感知相似，但哮喘肥胖患者的哮喘控制比非肥胖哮喘患者差。支气管和全身炎症特征以及肺功能变化的特定模式表明这些受试者的哮喘表型不同。
Clinicaltrials.gov标识符：NCT00532363和NCT00532831。
