Lv Nan, Xiao Lan, Camargo Carlos A, Wilson Sandra R, Buist A Sonia, Strub Peg, Nadeau Kari C, Ma Jun
1 Palo Alto Medical Foundation Research Institute, Palo Alto, California.
Ann Am Thorac Soc. 2014 Oct;11(8):1218-24. doi: 10.1513/AnnalsATS.201405-214OC.
Abdominal adiposity may be an important risk factor for uncontrolled asthma in adults, controlling for general obesity. Whether the relationship, if present, is explained by other factors (e.g., asthma onset age, sex, and/or coexisting conditions) is unclear.
To examine whether clinically applicable anthropometric measures of abdominal adiposity--waist circumference and waist-to-height ratio (WHtR)--are related to poorer asthma control in adults with uncontrolled asthma controlling for body mass index (BMI), and whether the relationship (if present) is explained by gastroesophageal reflux disorder (GERD), sleep quality, or obstructive sleep apnea (OSA) or differs by age of asthma onset or sex.
Patients aged 18 to 70 years with uncontrolled asthma (n = 90) participated in a 6-month randomized clinical trial.
Baseline measures included sociodemographics, standardized anthropometrics, Asthma Control Test (ACT), GERD Symptom Assessment Scale, Pittsburgh Sleep Quality Index, and Berlin Questionnaire for Sleep Apnea. Participants (mean [SD] age, 52 [12] yr) were racially and ethnically diverse, 67% women, and 69% overweight or obese, and 71% reported their age of asthma onset was 12 years or older. Participants had uncontrolled asthma (mean [SD] ACT score, 14.9 [3.7]) and low GERD symptoms score (0.6 [0.4]); 67% reported poor sleep quality, and 42% had a high OSA risk. General linear regression results showed that worse ACT scores were significantly associated with every SD increase in waist circumference (β = -1.03; 95% confidence interval [CI], -1.96 to -0.16; P = 0.02) and waist-to-height ratio (β = -1.16; 95% CI, -2.00 to -0.33; P = 0.008), controlling for sociodemographics. Waist-to-height ratio remained correlated with ACT (β = -2.30; 95% CI, -4.16 to -0.45; P = 0.02) after further adjusting for BMI. The BMI-controlled relationship between WHtR and ACT did not differ by age of asthma onset or sex (P > 0.05 for interactions) and persisted after additional adjustment for GERD, sleep quality, or OSA scores. Poor sleep quality was associated with worse ACT scores (β = -0.87; 95% CI, -1.71 to -0.03; P = 0.045) controlling for waist-to-height ratio, BMI, and sociodemographics.
Abdominal adiposity by waist-to-height ratio and poor sleep quality correlated with poorer asthma control in adults with uncontrolled asthma, after controlling for BMI and sociodemographics. These results warrant replication in larger studies of diverse populations. Clinical trial registered with www.clinicaltrials.gov (NCT 01725945).
腹部肥胖可能是成人哮喘控制不佳的一个重要危险因素，排除总体肥胖因素后依然如此。这种关系（如果存在）是否由其他因素（如哮喘发病年龄、性别和/或并存疾病）所解释尚不清楚。
探讨临床上适用的腹部肥胖人体测量指标——腰围和腰高比（WHtR）——是否与未得到控制的成年哮喘患者哮喘控制不佳相关，同时排除体重指数（BMI）的影响；以及这种关系（如果存在）是否由胃食管反流病（GERD）、睡眠质量或阻塞性睡眠呼吸暂停（OSA）所解释，或者是否因哮喘发病年龄或性别而有所不同。
年龄在18至70岁之间的未得到控制的哮喘患者（n = 90）参与了一项为期6个月的随机临床试验。
基线测量指标包括社会人口统计学信息、标准化人体测量指标、哮喘控制测试（ACT）、GERD症状评估量表、匹兹堡睡眠质量指数以及柏林睡眠呼吸暂停问卷。参与者（平均[标准差]年龄为52[12]岁）种族和民族多样，67%为女性，69%超重或肥胖，71%报告其哮喘发病年龄为12岁或以上。参与者的哮喘未得到控制（平均[标准差]ACT评分，14.9[3.7]）且GERD症状评分较低（0.6[0.4]）；67%报告睡眠质量差，42%有较高的OSA风险。一般线性回归结果显示，在控制社会人口统计学因素后，腰围每增加一个标准差，ACT评分更差与之显著相关（β = -1.03；95%置信区间[CI]，-1.96至-0.16；P = 0.02），腰高比也是如此（β = -1.16；95%CI，-2.00至-0.33；P = 0.008）。在进一步调整BMI后，腰高比仍与ACT相关（β = -2.30；95%CI，-4.16至-0.45；P = 0.02）。在控制BMI的情况下，WHtR与ACT之间的关系在哮喘发病年龄或性别方面没有差异（交互作用P>0.05），在进一步调整GERD、睡眠质量或OSA评分后依然存在。在控制腰高比、BMI和社会人口统计学因素后，睡眠质量差与更差的ACT评分相关（β = -0.87；95%CI，-1.71至-0.03；P = 0.045）。
在控制BMI和社会人口统计学因素后，腰高比所反映的腹部肥胖以及睡眠质量差与未得到控制的成年哮喘患者哮喘控制不佳相关。这些结果有待在更多样化人群的更大规模研究中进行重复验证。临床试验已在www.clinicaltrials.gov注册（NCT 01725945）。
