Frequency of headache among the employees of a rubber company in the state of São Paulo, Brazil

CONTEXT AND OBJECTIVE: Primary headaches may be responsible for absenteeism and a fall in the yield and productivity of work. The aim of this study was to establish the presence and frequency of primary headache among employees of a rubber shoe sole company, and its link to absenteism. DESIGN AND SETTING: Cross-sectional study carried out with help from the staff of the medical and social department of a rubber factory located in the municipality of Franca, São Paulo. METHOD: A questionnaire on headache characteristics was distributed to all employees. The returned and completed questionnaires were divided into two groups: with and without reports of headache. The headaches were classified into four main groups: migraine, tension-type headache (TTH), cluster headache and others. In terms of the reported frequency, headaches were also classified as chronic daily headache (CDH). RESULTS: The number of valid questionnaires was 392 (59 percent); 80.9 percent were from male and 19.1 percent from female employees. Headaches were reported by 120 subjects (30.6 percent), with 17.4 percent belonging to the migraine group and 8.9 percent to the TTH group. Migraine was more frequent (p < 0.001) among all participants and also among the women (p < 0.05). TTH was more frequent among the men (p < 0.05). CDH was identified in 14 individuals (3.6 percent). CONCLUSIONS: Headache was a common problem among the employees of this company and was a cause of absenteeism for 8.7 percent of the respondents to the questionnaire.