OCCUPATION AND OCCUPATIONAL EXPOSURE TO UV-LIGHT AS RISK-FACTORS FOR HAIRY-CELL LEUKEMIA EVALUATED IN A CASE-CONTROL STUDY

To investigate the role of occupation as a risk factor for hairy cell leukaemia a case-control study on 121 male, hairy cell leukaemia (HCL) patients, and 484 controls matched for age and sex, was conducted. We found significantly elevated risk for HCL among building painters (OR , 5.7; 95% CI, 1.6-20.8; based on six cases and four controls) and con struction workers (OR, 3.3; CI, 1.2-9.2; based on seven cases and eigh t controls). Farming has been suggested as a risk factor in HCL. In th is investigation farmers had an OR of 1.2 (CI, 0.6-2.3) and farm worke rs an OR of 1.5 (CI, 0.8-2.8). However, having ever worked in farming yielded an OR of 1.8 (CI, 1.1-2.9). Having grown up mainly in a rural area gave an OR of 1.4 (CI, 0.9-2.4). UV light has been suggested as a risk factor for non-Hodgkin's lymphoma (NHL). To evaluate the impact of UV exposure, classification of occupations as indoor, outdoor or mi xed indoor/outdoor was made. Outdoor and mixed outdoor/indoor work yie lded ORs of 2.3 (1.0-4.9) and 1.6 (1.0-2.5), respectively. When the ef fect of outdoor/indoor or mixed indoor/outdoor work was analysed using a scoring system the OR was 2.0 (CI, 0.9-4.4) for farmers compared wi th 0.8 (CI, 0.3-1.9) among non-farmers in the highest scoring group. T here was no clear correlation between socioeconomic status as defined by the Swedish Socio-Economic Classification (SEI), and the risk of HC L. As many comparisons were made, the possibility of associations occu rring by chance can not be excluded.