[Case-control survey on risk factors of benign vocal fold lesions].

Objective To investigate the risk factors that may relate with benign vocal fold lesions including vocal fold nodule, vocal fold polyp, chronic laryngitis and Reinke's edema. Methods In present series, 321 cases who were performed laryngoscope were invited to participate the survey. Among them 168 cases with benign vocal fold lesions composed the case group. Another 153 cases with normal larynx composed the control group. Each case were undertook the same questionnaire. Logistic regression analysis was preformed to investigate the possible risk factors. Results The result demonstrated the occurring of benign vocal fold lesions positively correlated to five factors, including occupation, work or residence environment noise, alcohol-consuming, voice-using hours per day and abuse of voice. Occupations with intensive voice - use were more vulnerable to developing these disorders. Occurring risk of occupations type Ⅱ with moderate voice-use was 1. 934 times than that of occupations type Ⅰ with lesser voice-use （ OR = 1. 934）. And risk of occupations type Ⅲ with upper voice-use was 2. 633 times than that of type Ⅰ. Risk raised 1. 302 times with each more hour of voice use per day. OR of the following factors of voice abuse, environment noise, alcohol-consuming was 4. 744, 2. 115 and 2. 177, respectively. Conclusions The result suggested that people should abstain from alcohol, lowering the environment noise, prevent overuse and abuse of voice in order to decrease the prevalence of these disorders, which is especially important for the professional voice users, e.g. teachers or managers. The essential therapy for these disorders is to correct bad phonation habits. Key words: Voice disorders; Risk factors; Case-control studies