1State Key Laboratory of Respiratory Disease, Guangzhou Institute of Respiratory Diseases, First Affiliated Hospital, Guangzhou Medical University , Guangzhou, Guangdong , China.
COPD. 2013 Oct;10(5):567-72. doi: 10.3109/15412555.2013.781579. Epub 2013 Jul 11.
An association between chronic obstructive pulmonary disease (COPD) and low body mass index (BMI) has been well established in cross-sectional studies. However, there have been few cohort studies investigating this issue. We therefore aimed to address this gap.
Two population-based studies, a cross-sectional study including 1818 subjects and a subsequent 4-year cohort study consisting of 759 individuals without COPD, were conducted in Guangzhou, China. Every subject was 40 years old or older at the time of recruitment and completed questionnaire interviews, anthropometric measurements and spirometry testing. As a follow-up, each subject underwent annual pre-bronchodilator spirometry testing. Subjects with a pre-bronchodilator FEV1/FVC <0.7 were required to undergo post-bronchodilator spirometry testing. Subjects with a post-bronchodilator FEV1/FVC <0.7 were diagnosed with COPD.
Compared to subjects with normal BMI (18.5 to 23.9 kg/m(2)), those with low BMI (<18.5 kg/m(2)) had a higher prevalence of COPD (21.1% vs. 7.5%), with an adjusted OR of 2.75 [95% confidence intervals (CI): 1.69 to 4.47]. Both low BMI and obese (≥ 28.0 kg/m(2)) subjects had lower FEV1 after adjustment. This association was further confirmed in the cohort study; non-COPD subjects with low BMI at baseline were more likely to develop COPD (RR = 2.88, 95% CI: 1.06 to 7.85), independent of smoking status and other confounders.
Low BMI was not only a systemic consequence of COPD but also an important risk factor for the development of COPD, which raises the possibility that early intervention in subjects with low BMI may reduce the incidence of COPD.
在横断面研究中，慢性阻塞性肺疾病（COPD）与低体重指数（BMI）之间的关联已得到充分证实。然而，针对这一问题的队列研究却很少。因此，我们旨在解决这一空白。
在中国广州进行了两项基于人群的研究，一项包括 1818 名受试者的横断面研究和一项随后的 4 年队列研究，该队列研究由 759 名无 COPD 的个体组成。每个受试者在招募时年龄在 40 岁或以上，并完成了问卷调查、人体测量和肺活量测定。作为随访，每个受试者都接受了年度支气管扩张剂前肺活量测定。需要进行支气管扩张剂后肺活量测定的受试者为支气管扩张剂前 FEV1/FVC<0.7。诊断为 COPD 的受试者为支气管扩张剂后 FEV1/FVC<0.7。
与 BMI 正常（18.5 至 23.9kg/m2）的受试者相比，BMI 较低（<18.5kg/m2）的受试者 COPD 患病率更高（21.1%比 7.5%），调整后的 OR 为 2.75（95%CI：1.69 至 4.47）。低 BMI 和肥胖（≥28.0kg/m2）受试者的 FEV1 均较低。在队列研究中进一步证实了这一关联；基线时 BMI 较低的非 COPD 受试者更有可能发展为 COPD（RR=2.88，95%CI：1.06 至 7.85），独立于吸烟状况和其他混杂因素。
低 BMI 不仅是 COPD 的全身性后果，也是 COPD 发展的重要危险因素，这提示早期干预低 BMI 受试者可能会降低 COPD 的发病率。
