Risk factors for laryngeal cancer.

This case-control study comprised 100 histologically verified laryngeal cancer patients and 100 hospital controls matched with cases by sex, age and place of residence. The following variables were tested for their association with cancer of the larynx: marital status, educational level, hard liquor consumption, cigarette smoking, unfavorable working conditions, sudden and frequent temperature changes at work, cold housing, loud speech at work, frequent hoarseness, frequent and persistent cough, persistently swollen neck glands, tonsillectomy and laryngeal surgery. According to conditional logistic regression analysis, significant association with laryngeal cancer was found for unfavourable working conditions for more than 10 years (OR = 4.36; 95% CI = 1.92-9.91), hard liquor consumption for more than 5 years (OR = 2.59; 95% CI = 1.14-5.87), cigarette smoking for more than 10 years (OR = 7.29; 95% CI = 2.41-22.09), tonsillectomy (OR = 4.80; 95% CI = 1.61-14.30) and frequent and persistent cough prior to disease (OR = 8.17; 95% CI = 1.72-38.76).