American Journal of Hematology 38:147-149 (1991)
Occupational Risk for Hematological Malignancies Paolo Pasqualetti, Raffaele Casale, Domenico Colantonio, and Antonio Collacciani Department of Internal Medicine, School of Medicine and Surgery, Chair of Medical Pathology, University of LAquila (P.P., R.C., D.C.) and Division of Internal Medicine, Section of Hematology, General Hospital of Avezzano (A.C.), L’Aquila, Italy
A case-control study was conducted in 620 cases of hematological malignancies and in 1,240 age- and sex-matched controls in order to verify the possible association between occupation, toxic substances exposure, and the risk of hematological neoplasias. The results demonstrate that farmers and industrial workers have a significant risk for hematological malignancies. Exposure to asbestos, aromatic hydrocarbons, fertilizers, mineral oils, pesticides,and radiationsis associatedwith a significant increase in the risk for these malignant diseases. These data are in agreement with previously reported data, and require a confirmation in larger, prospective studies. Key words: occupation, exposure to toxic substances,case-control study, epidemiology
INTRODUCTION
The incidence of cancer is increasing in western countries [ 11, and several environmental and occupational risk factors have been suggested to explain this trend. The proportion of cancer deaths attributed to occupational factors is provisionally estimated as 4.0% [2], but this percentage seems to be underestimated [ 11. A case-referent study was conducted in order to investigate the possible association between occupation, exposure to occupational toxic substances, and risk of hematological malignancies. PATIENTS, CONTROLS, AND METHODS
nomic status [3], area of residence, alcohol intake, tobacco smoking, current or previous occupation, and if they had ever been exposed to one or more of a list of toxic substances. Out of the 620 case interviews, 366 (59%) were obtained directly, whereas 1,054 (85%) of the 1,240 control interviews were provided by the subjects; in the other cases, the information was obtained from their relatives, Exposures to occupational toxic substances were grouped in 21 risk categories, such as reported by Morris et al. [4]. A matched-pair analysis was used with the relative risk of hematological malignancies estimated by the odds ratio (OR) of discordant pairs (bk); and the confidence intervals at 95% of probability (95%CI) were computed on the basis of the normal approximation; the statistical significance of each association was calculated using the “Mantel’s chi-square test,” with a degree of freedom; finally, also the etiological fraction of each association was calculated [5].All these procedures have been reported previously in detail [6].
A total of 620 cases of hematological malignancies, 355 males and 275 females, ages ranging from 24 to 85 years, and 1,240 sex- and age-matched hospital controls were considered for the study. Among the patients, there were 59 cases with acute non-lymphoblastic leukemia (ANLL), 29 with acute lymphoblastic leukemia (ALL), 65 with chronic lymphocytic leukemia (CLL), 69 with Hodgkin disease (HD), 108 with non-Hodgkin lym- RESULTS phoma (NHL), 44 with myeloproliferative syndromes Table I summarizes the results. No significant (MPS), 48 with myelodysplatic syndromes (MDS), 198 ( P > 0.05) association was demonstrated for socioecowith malignant monoclonal gammopathies (MG), 190 multiple myeloma, and 8 with Waldenstrom’s macroglobulinemia. The controls were selected from the same Received for publication March 28, 1991; accepted April 8, 1991. geographic areas as the cases, and were affected with Address reprint requests to Paolo Pasqualetti, M.D., Department of “medical diseases,” except cancer or congenital diseases. Internal Medicine, School of Medicine and Surgery, Chair of Medical All subjects, cases and controls, were interviewed, Pathology, University of L’Aquila, Via san Sisto, n.22/E, 1-67100 without knowledge of subject’s state, about socioeco- L’Aquila, Italy. 0 1991 Wiley-Liss, Inc.
148
Brief Report: Pasqualetti et al.
TABLE I. Association Between Socioeconomic Status, Occupation, Occupational Exposures, and Risk of Hematological Malignancies
Categories of risk Socioeconomic status High Medium Low Residence Urban Rural Habits Alcohol Tobacco Occupations Private practitioners Office workers Teachers Medical doctors and nurses Sales workers Building workers Industry workers Handcraftmen Auto mechanics Railroad workers Farmers Housekeepers Others Exposures Acids Aldehydes and ketones Aliphatic hydrocarbons Alkalies Aromatic hydrocarbons Asbestos Carbon monoxide Chemical asphyxiants Chlorinated hydrocarbons Dusts Dyes and inks Esters Ethers Fertilizers Metals Mineral oils Organically high polymeres Other caustic substances Paints and related products Pesticides Radiation
Cases
Controls
b/c"
OR
95% CI
P
EF, %
172 245 203
402 443 395
861I97 691 164 811108
0.87 0.84 1S O
(0.68 + 1.08) (0.63 + 1.1 1) (1.12 + 1.98)
ns ns ns
33.0
326 294
635 605
87/163 931171
1.07 1.09
(0.83 f 1.39) (0.85 + 1.40)
ns ns
6.5 8.3
256 228
482 425
681162 761131
0.84 1.16
(0.63 + 1.1 1) (0.87 f 1.54)
ns ns
3.8
55 92 16 23 18 67
138 228 58 54 43 125 178 59 16 19 229 58 45
29/83 581123 11/24 18/27 12/26 39/75 58/39 21/26 519 715 71/52 16/47 18/32
0.70 0.94 0.92 1.33 0.92 1.04 2.97 1.62
ns ns ns ns ns ns
Occupational Risk for Hematological Malignancies Paolo Pasqualetti, Raffaele Casale, Domenico Colantonio, and Antonio Collacciani Department of Internal Medicine, School of Medicine and Surgery, Chair of Medical Pathology, University of LAquila (P.P., R.C., D.C.) and Division of Internal Medicine, Section of Hematology, General Hospital of Avezzano (A.C.), L’Aquila, Italy
A case-control study was conducted in 620 cases of hematological malignancies and in 1,240 age- and sex-matched controls in order to verify the possible association between occupation, toxic substances exposure, and the risk of hematological neoplasias. The results demonstrate that farmers and industrial workers have a significant risk for hematological malignancies. Exposure to asbestos, aromatic hydrocarbons, fertilizers, mineral oils, pesticides,and radiationsis associatedwith a significant increase in the risk for these malignant diseases. These data are in agreement with previously reported data, and require a confirmation in larger, prospective studies. Key words: occupation, exposure to toxic substances,case-control study, epidemiology
INTRODUCTION
The incidence of cancer is increasing in western countries [ 11, and several environmental and occupational risk factors have been suggested to explain this trend. The proportion of cancer deaths attributed to occupational factors is provisionally estimated as 4.0% [2], but this percentage seems to be underestimated [ 11. A case-referent study was conducted in order to investigate the possible association between occupation, exposure to occupational toxic substances, and risk of hematological malignancies. PATIENTS, CONTROLS, AND METHODS
nomic status [3], area of residence, alcohol intake, tobacco smoking, current or previous occupation, and if they had ever been exposed to one or more of a list of toxic substances. Out of the 620 case interviews, 366 (59%) were obtained directly, whereas 1,054 (85%) of the 1,240 control interviews were provided by the subjects; in the other cases, the information was obtained from their relatives, Exposures to occupational toxic substances were grouped in 21 risk categories, such as reported by Morris et al. [4]. A matched-pair analysis was used with the relative risk of hematological malignancies estimated by the odds ratio (OR) of discordant pairs (bk); and the confidence intervals at 95% of probability (95%CI) were computed on the basis of the normal approximation; the statistical significance of each association was calculated using the “Mantel’s chi-square test,” with a degree of freedom; finally, also the etiological fraction of each association was calculated [5].All these procedures have been reported previously in detail [6].
A total of 620 cases of hematological malignancies, 355 males and 275 females, ages ranging from 24 to 85 years, and 1,240 sex- and age-matched hospital controls were considered for the study. Among the patients, there were 59 cases with acute non-lymphoblastic leukemia (ANLL), 29 with acute lymphoblastic leukemia (ALL), 65 with chronic lymphocytic leukemia (CLL), 69 with Hodgkin disease (HD), 108 with non-Hodgkin lym- RESULTS phoma (NHL), 44 with myeloproliferative syndromes Table I summarizes the results. No significant (MPS), 48 with myelodysplatic syndromes (MDS), 198 ( P > 0.05) association was demonstrated for socioecowith malignant monoclonal gammopathies (MG), 190 multiple myeloma, and 8 with Waldenstrom’s macroglobulinemia. The controls were selected from the same Received for publication March 28, 1991; accepted April 8, 1991. geographic areas as the cases, and were affected with Address reprint requests to Paolo Pasqualetti, M.D., Department of “medical diseases,” except cancer or congenital diseases. Internal Medicine, School of Medicine and Surgery, Chair of Medical All subjects, cases and controls, were interviewed, Pathology, University of L’Aquila, Via san Sisto, n.22/E, 1-67100 without knowledge of subject’s state, about socioeco- L’Aquila, Italy. 0 1991 Wiley-Liss, Inc.
148
Brief Report: Pasqualetti et al.
TABLE I. Association Between Socioeconomic Status, Occupation, Occupational Exposures, and Risk of Hematological Malignancies
Categories of risk Socioeconomic status High Medium Low Residence Urban Rural Habits Alcohol Tobacco Occupations Private practitioners Office workers Teachers Medical doctors and nurses Sales workers Building workers Industry workers Handcraftmen Auto mechanics Railroad workers Farmers Housekeepers Others Exposures Acids Aldehydes and ketones Aliphatic hydrocarbons Alkalies Aromatic hydrocarbons Asbestos Carbon monoxide Chemical asphyxiants Chlorinated hydrocarbons Dusts Dyes and inks Esters Ethers Fertilizers Metals Mineral oils Organically high polymeres Other caustic substances Paints and related products Pesticides Radiation
Cases
Controls
b/c"
OR
95% CI
P
EF, %
172 245 203
402 443 395
861I97 691 164 811108
0.87 0.84 1S O
(0.68 + 1.08) (0.63 + 1.1 1) (1.12 + 1.98)
ns ns ns
33.0
326 294
635 605
87/163 931171
1.07 1.09
(0.83 f 1.39) (0.85 + 1.40)
ns ns
6.5 8.3
256 228
482 425
681162 761131
0.84 1.16
(0.63 + 1.1 1) (0.87 f 1.54)
ns ns
3.8
55 92 16 23 18 67
138 228 58 54 43 125 178 59 16 19 229 58 45
29/83 581123 11/24 18/27 12/26 39/75 58/39 21/26 519 715 71/52 16/47 18/32
0.70 0.94 0.92 1.33 0.92 1.04 2.97 1.62
ns ns ns ns ns ns
