哮喘联盟

   背景：近几十年来肥胖和过敏性疾病显著增加。尽管已经证实肥胖与哮喘有关，但人们对肥胖与变应性致敏的关系还未形成共识。
目的：检测肥胖和血脂水平与变应性致敏的关系。
   方法：本研究选择1187名18～39岁的中国农村双胞胎（653名男性）为研究对象，进行皮肤点刺试验、进行各项人体测量和双能X线吸收测量法评估肥胖、检测血脂水平。将变应性致敏定义为对1种及1种以上变应原（检测了9种食物和5种气传变应原）SPT阳性。我们应用按性别分层的广义估计方程来评估肥胖和血清脂质水平与变应性致敏的相关性，并应用结构方程模型估计遗传或环境因素对这些相关性的影响。
   结果：男性的体脂率（%BF）比女性低（13.9% vs. 28.8%），但变应性致敏的发生率高于女性（56.2% vs. 36.7%）。%BF上四分位数的男性其致敏性是%BF下四分位数的男性的2.1倍（95% CI, 1.3-3.5; P趋势 = 0.003）。男性中，当高密度脂蛋白（HDL）<40 mg/dL（比率= 4.0; 95% CI, 1.8-9.2）、低密度脂蛋白（LDL）四分位数较大（P趋势 = 0.007）时变应性致敏的风险增加。血清脂质水平和变应性致敏两者受某些共同的遗传因素影响部分解释了这些结果。女性中，HDL水平较低与变应性致敏风险增加有关。
    结论：本研究中的中国人群偏瘦，该人群中%BF 较高、HDL水平较低和LDL水平较高与变应性致敏的风险增加有关，这种相关性在男性中最明显。男性中这种肥胖、血清脂质水平和变应性致敏的相关性通过对这些性状共同的遗传影响部分得以说明。

                                                             （苏楠 审校）
Ouyang F, et al. J Allergy Clin Immunol. 2009 Jan 7. [Epub ahead of print]

 Ouyang F, et al. J Allergy Clin Immunol. 2009 Jan 7. [Epub ahead of print]
Adiposity, serum lipid levels, and allergic sensitization in Chinese men and women.

BACKGROUND: Obesity and allergic diseases have increased dramatically in recent decades. Although adiposity has been associated with asthma, associations with allergic sensitization have been inconsistent.
OBJECTIVE: To examine the association of adiposity and lipid profiles with allergic sensitization.
METHODS: This study included 1187 rural Chinese twins (653 men) age 18 to 39 years, with skin prick tests, anthropometric and dual-energy x-ray absorptiometry-assessed adiposity measures, and lipid assessments. Allergic sensitization was defined as positive SPT to >/=1 allergen (9 foods and 5 aeroallergens tested). We applied sex-stratified generalized estimating equations to assess the association of adiposity and serum lipids with allergic sensitization, and structural equation models to estimate the genetic/environmental influences on any observed associations.
RESULTS: Men had lower percent body fat (% BF) (13.9% vs. 28.8%) but higher rates of allergic sensitization (56.2% vs 36.7%) than women. Men in the highest %BF quartile were 2.1 times more likely to be sensitized than the lowest quartile (95% CI, 1.3-3.5; P trend = .003). In men, the risk of allergic sensitization increased with high-density lipoprotein (HDL) <40 mg/dL (odds ratio = 4.0; 95% CI, 1.8-9.2) and higher low-density lipoprotein quartiles (P trend = .007). This appeared to be partially explained by shared genetic factors between serum lipid levels and allergic sensitization. In females, lower HDL was associated with increased risk of allergic sensitization.
CONCLUSION: In this relatively lean Chinese population, higher %BF, lower HDL and higher LDL were associated with greater risk of allergic sensitization, most notable in men. The observed associations among adiposity, serum lipids, and allergic sensitization in men appear to be partially explained by common genetic influences on these traits.