Laboratory of Clinical Exercise Physiology and Respiratory Investigation Unit; Division of Respirology, Kingston Health Science Center; Queen's University, Kingston, ON, Canada.
Laboratory of Clinical Exercise Physiology and Respiratory Investigation Unit; Division of Respirology, Kingston Health Science Center; Queen's University, Kingston, ON, Canada.
Chest. 2020 Oct;158(4):1576-1585. doi: 10.1016/j.chest.2020.04.006. Epub 2020 Apr 15.
Massively obese subjects frequently undergo pulmonary function tests nowadays. Obesity-associated decreases in key operating lung volumes (reduced inspiratory capacity and reduced vital capacity) are particularly concerning because they may shorten the "room" for tidal volume expansion with negative physiologic and sensory consequences.
Is massive obesity associated with reduced operating lung volumes? If so, is this effect more pronounced in men than women?
We performed an observational, retrospective study in a tertiary, hospital-based laboratory. Pulmonary function test results from 248 super-obese (SO; BMI, 50 to 59.9 kg/m) and 83 super-super obese (SSO; BMI, ≥60 kg/m) men and women were analyzed. Electronic medical records were screened to ensure that subjects were free of any disease that potentially could interfere with lung volumes.
The prevalence of a low total lung capacity (restriction) was 26.9%, which increased to 38.6% in SSO. Despite the absence of between-sex differences in BMI and spirometric variables derived from the forced maneuver in both SO and SSO, men presented with higher prevalence of restriction (46.7%) than women (19.4%) (P < .05). Between-sex differences in residual volume differed according to the BMI group; SO men presented with higher values than SO women; the opposite was found in the SSO group. The prevalence of restriction with low operating lung volumes was approximately twice (SSO) and approximately thrice (SSO) as high in men compared with women (P < .01). Linear prediction equations as a function of sex, demographic, and anthropometric attributes markedly reduced the prevalence of these abnormalities across the population.
Obesity-related restriction leading to low operating lung volumes is highly prevalent in the massively obese subject, particularly in men. These alterations that are associated with massive obesity should be taken into consideration for an accurate interpretation of pulmonary function tests in this growing population.
目前，大量肥胖患者经常进行肺功能测试。与肥胖相关的关键肺功能容量降低（吸气量减少和肺活量减少）尤其令人担忧，因为这可能会缩小潮气量扩张的“空间”，从而产生负面的生理和感觉后果。
肥胖是否与肺功能容量降低有关？如果是，这种影响在男性中比女性更明显吗？
我们在一家三级医院的实验室进行了一项观察性、回顾性研究。分析了 248 名超级肥胖（SO；BMI 为 50 至 59.9kg/m）和 83 名超级超级肥胖（SSO；BMI≥60kg/m）男女的肺功能测试结果。筛选电子病历以确保受试者没有任何可能影响肺容量的疾病。
低总肺容量（限制）的患病率为 26.9%，在 SSO 中增加到 38.6%。尽管在 SO 和 SSO 中，男女之间的 BMI 和强制操作得出的肺活量变量没有性别差异，但男性的限制（46.7%）患病率高于女性（19.4%）（P<.05）。根据 BMI 组，残气量的性别差异不同；SO 男性的残气量值高于 SO 女性；SSO 组则相反。男性低肺功能容量限制的患病率大约是女性的两倍（SSO）和三倍（SSO）（P<.01）。作为性别、人口统计学和人体测量属性的函数的线性预测方程，大大降低了人群中这些异常的患病率。
肥胖相关的限制导致大量肥胖患者的肺功能容量降低，特别是在男性中。在这个不断增长的人群中，对于肺功能测试的准确解释，应该考虑这些与肥胖相关的改变。
