Hedström A K, Lima Bomfim I, Hillert J, Olsson T, Alfredsson L
Institute of Environmental Medicine, Karolinska Institutet, Stockholm, Sweden.
Eur J Neurol. 2015 Mar;22(3):578-e38. doi: 10.1111/ene.12620. Epub 2014 Dec 20.
The possible interaction between adolescent obesity and past infectious mononucleosis (IM) was investigated with regard to multiple sclerosis (MS) risk.
This report is based on two population-based case-control studies, one with incident cases (1780 cases, 3885 controls) and one with prevalent cases (4502 cases, 4039 controls). Subjects were categorized based on adolescent body mass index (BMI) and past IM and compared with regard to occurrence of MS by calculating odds ratios with 95% confidence intervals (CIs) employing logistic regression. A potential interaction between adolescent BMI and past IM was evaluated by calculating the attributable proportion due to interaction.
Regardless of human leukocyte antigen (HLA) status, a substantial interaction was observed between adolescent obesity and past IM with regard to MS risk. The interaction was most evident when IM after the age of 10 was considered (attributable proportion due to interaction 0.8, 95% CI 0.6-1.0 in the incident study, and attributable proportion due to interaction 0.7, 95% CI 0.5-1.0 in the prevalent study). In the incident study, the odds ratio of MS was 14.7 (95% CI 5.9-36.6) amongst subjects with adolescent obesity and past IM after the age of 10, compared with subjects with none of these exposures. The corresponding odds ratio in the prevalent study was 13.2 (95% CI 5.2-33.6).
An obese state both impacts the cellular immune response to infections and induces a state of chronic immune-mediated inflammation which may contribute to explain our finding of an interaction between adolescent BMI and past IM. Measures taken against adolescent obesity may thus be a preventive strategy against MS.
就多发性硬化症（MS）风险，对青少年肥胖与既往传染性单核细胞增多症（IM）之间可能存在的相互作用进行了调查。
本报告基于两项基于人群的病例对照研究，一项针对新发病例（1780例病例，3885例对照），另一项针对现患病例（4502例病例，4039例对照）。根据青少年体重指数（BMI）和既往IM情况对研究对象进行分类，并通过使用逻辑回归计算比值比及95%置信区间（CI），比较MS的发病情况。通过计算交互作用归因比例，评估青少年BMI与既往IM之间的潜在交互作用。
无论人类白细胞抗原（HLA）状态如何，在MS风险方面，青少年肥胖与既往IM之间均观察到显著的交互作用。当考虑10岁以后发生的IM时，这种交互作用最为明显（在新发病例研究中，交互作用归因比例为0.8，95%CI为0.6 - 1.0；在现患病例研究中，交互作用归因比例为0.7，95%CI为0.5 - 1.0）。在新发病例研究中，与无这些暴露因素的研究对象相比，有青少年肥胖且10岁以后有既往IM的研究对象发生MS的比值比为14.7（95%CI为5.9 - 36.6）。现患病例研究中的相应比值比为13.2（95%CI为5.2 - 33.6）。
肥胖状态既影响对感染的细胞免疫反应，又诱导慢性免疫介导的炎症状态，这可能有助于解释我们所发现的青少年BMI与既往IM之间的交互作用。因此，针对青少年肥胖采取的措施可能是预防MS的一种策略。
