[Occupational and environmental risk factors for essential thrombocythemia: a case-control study].

Background: Essential Thrombocythemia (ET) is a chronic myeloproliferative disorder characterized by a long median survival, even though serious complications such as acute hemorrhagic or thrombotic events are not infrequent. Very few information are available about risk factors for ET because of lack of epidemiological studies focused on this topic.

Methods: We conducted a case-control study in order to analyze the possible association between ET and some occupational and environmental risk factors. A total of 93 patients enrolled in two hospitals in Turin (Italy) and 280 subjects randomly selected from the general population as controls, were included in the analysis.

Results: We found an association between ET and selected occupations. OR estimates suggest a significant association between ET cooks/waiters (OR 4.96, CI 1.59-16.9) and clerks (OR 2.63, CI 1.53-4.51) and a non significant association between ET and hairdressers (OR 5.10, CI 0.82-31.4), nurses (OR 3.75, CI 0.80-19.4), farmers (OR 1.74, CI 0.84-3.56), electricians (OR 1.42, CI 0.48-3.78), and photographers (OR infinity). Data did not suggest any strong association between environmental risk factors and ET.

Conclusions: Selected occupations seem to be associated to ET. The association of ET with occupations as hairdressers, farmers and electricians could be attributable to known risk factors for other hematolymphopoietic malignancies such as hair dye, pesticides and magnetic fields. The association with other occupations is more difficult to explain, but all the results we presented are consistent with data from previous studies on onco-hematological diseases.