方法：选取2015-04/09间在山西省眼科医院眼表疾病门诊就诊的患者及其陪同家属共440例为研究对象，年龄控制在40岁以下，取得患者知情同意后，行面对面访谈式问卷调查并依次行裂隙灯显微镜检查、泪膜破裂时间(tear break-up time，BUT)测定、泪液分泌试验(Schirmer Ⅰ test，SⅠt)、角膜荧光素染色(fluorescein，FL)等检查并记录检查结果。将确诊为干眼症的259例患者作为病例组，181例非干眼症患者作为对照组，采用病例对照研究的方法。

结果：研究对象 440例，男205例(46.6%)，女235例(53.4%)。确诊干眼症259例，患病率为58.9%。在单因素分析的基础上进行多元Logistic 回归分析，结果显示，屈光不正(OR=4.582，95%CI：2.789～7.562)、每天阅读写作时间长(OR=1.380，95%CI：1.111～1.715)、阅读写作姿势不标准(OR=4.202，95%CI：2.531～6.977)、配戴隐形眼镜(OR=3.374，95%CI：1.837～6.196)、联合使用眼药(OR=3.749，95%CI：1.608～8.740)、鼻炎史(OR=2.244，95%CI：1.412～4.410)、角结膜炎史(OR=3.971，95%CI：2.005～7.866)、LASIK手术史(OR=4.494， 95%CI：0.988～20.447)、家附近1km内有污染建筑(OR=3.039，95%CI：1.185～7.796)为干眼症的危险因素。

结论：眼科门诊40岁以下人群干眼症患病率远高于一般人群。人们的不良生活习惯、行为方式、环境污染为40岁以下人群干眼症的主要危险因素。

METHODS:A total of 440 patients aged below 40 were selected from Apr. to Sep.2015 in Shanxi Eye Hospital for the study. After obtaining the informed consent of the patient, they underwent face to face interviews with questionnaires to obtain relevant information. The tear break-up time, Schirmer I test, corneal fluorescein staining were measured and recorded. A total of 259 dry eye patients were pathological group, and the remaining 181 cases were the control group. A case control study was used.

RESULTS: Four hundred and forty cases included 205 male(46.6%)and 235 female(53.4%)patients diagnosed 259 cases(58.9%)with dry eye. The result of Logistic regression analysis revealed that refractive errors(OR=4.582, 95%CI=2.789-7.562), daily reading and writing time more than 4h(OR=1.380, 95%CI=1.111-1.715), non-standard reading and writing posture(OR=4.202, 95%CI=2.531-6.977), wearing contact lenses(OR=3.374, 95%CI=1.837-6.196), combination of ophthalmic(OR=3.749, 95%CI=1.608-8.740), rhinitis(OR=2.244, 95%CI=1.412-4.410), conjunctivitis(OR=3.971, 95%CI=2.005-7.866), LASIK surgery(OR=4.494, 95%CI=0.988-20.447), neighborhood within 1 km has pollution building(OR=3.039, 95%CI=1.185-7.796)were risk factors for dry eye.

CONCLUSION: The prevalence of ophthalmology clinic under the age of 40 in patients with dry eye is far higher than the general prevalence. The results indicate that people's bad habits, behavior and environmental pollution are risk factors for dry eye.