Lifestyle factors and risk of leukemia and non-Hodgkin's lymphoma: a case-control study.

PURPOSE: Risk factors for leukemia and lymphomas in adults are largely unknown. This study was aimed at evaluating the association between lifestyle factors and the risk of hematological malignancies in an adult population. METHODS: Data were drawn from a population-based case-control study carried out in Italy and included 294 cases (199 lymphoid and 95 myeloid) and 279 controls. Analyses were performed using standard multivariable logistic regression. RESULTS: Hair dye use for at least 15 years was associated with a higher risk of lymphoid malignancies among females (OR 2.3, 95 % CI 1.0-4.9, p = 0.036, test for trend). Furthermore, a protective effect of a moderate to heavy tea consumption on the risk of myeloid malignancies was observed (OR 0.4, 95 % CI 0.2-0.9, p = 0.017). No association was found for the use of alcoholic beverages and tobacco smoking. CONCLUSIONS: Our results confirm the potential carcinogenic effect of prolonged hair dye use observed in previous investigations. The excess risk could be explained by exposure to a higher concentration of toxic compounds in hair products used in the past. The protective effect of regular tea consumption observed in an area with a very high prevalence of black tea consumers deserves further investigation.

Chronic diseases, medical history and familial cancer, and risk of leukemia and non-Hodgkin's lymphoma in an adult population: a case-control study.

PURPOSE: This investigation was aimed at evaluating the association between chronic diseases, medical history and familial cancer, and the risk of developing hematological malignancies. METHODS: Data were drawn from a population-based case-control study carried out to assess the risk of non-Hodgkin's lymphoma and leukemia in an adult population exposed to environmental air pollution in Northern Italy. Each case was classified according to the WHO ICD-O-3 classification. Statistical analyses were performed by multivariable unconditional logistic regression in 573 interviewed subjects (199 lymphoid cases, 95 myeloid cases, and 279 healthy controls). RESULTS: Lymphoid malignancies were associated with a history of gastroduodenal ulcer (OR 2.1, 95 % CI 1.2-3.6), rheumatoid arthritis (OR 4.4, 95 % CI 1.3-19.0), anemia (OR 3.3, 95 % CI 1.2-9.3), cholecystectomy (OR 2.9, 95 % CI 1.0-8.0), heavy diagnostic X-ray exposure (OR 2.1, 95 % CI 1.3-3.7), and a familial risk of non-Hodgkin's lymphoma (OR 10.1, 95 % CI 1.3-458). Myeloid malignancies were associated with non-neoplastic thyroid diseases (OR 6.2, 95 % CI 1.7-35.6) and anemia (OR 6.8, 95 % CI 2.0-23.1). Subgroup analysis highlighted an excess risk of MALT in patients with gastroduodenal ulcer (OR 5.3, 95 % CI 1.04-23.7) and of AML in patients with rheumatoid arthritis (OR 6.9, 95 % CI 1.2-38.1), and of MDS in subjects exposed to heavy diagnostic X-ray (OR 3.4, 95 % CI 1.03-11.2) when the analysis was restricted to irradiation of pelvis, abdomen, or thorax. CONCLUSIONS: Most observed associations confirm results from previous studies. The higher risk of lymphoid malignancies among patients with a history of cholecystectomy needs further investigations.

Infectious diseases and risk of leukemia and non-Hodgkin's lymphoma: a case-control study.

The aim of this investigation was to evaluate the association between common infectious diseases and the risk of hematological malignancies in an adult population. Data were drawn from a population based case-control study that included 165 cases (125 lymphoid and 40 myeloid neoplasms) and 233 controls. Occurrence of childhood diseases (measles, rubella, chickenpox, mumps, pertussis and scarlet fever) was slightly inversely associated with the risk of both malignancies, but statistical significance was not reached. The data of infections occurring after 14 years of age indicated an increasing risk of lymphoid malignancies (OR=2.9, p<0.05).