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Pordanjani SR, Kavousi A, Mirbagheri B, Shahsavani A, Etemad K. Spatial analysis and geoclimatic factors associated with the incidence of acute lymphoblastic leukemia in Iran during 2006-2014: An environmental epidemiological study. ENVIRONMENTAL RESEARCH 2021; 202:111662. [PMID: 34273372 DOI: 10.1016/j.envres.2021.111662] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/09/2021] [Revised: 06/09/2021] [Accepted: 07/05/2021] [Indexed: 06/13/2023]
Abstract
BACKGROUND AND OBJECTIVES The present study aims to determine the cumulative incidence rate of acute lymphoblastic leukemia (ALL), the degree of spatial autocorrelation and clustering of ALL, the hotspot and coldspots of ALL and geoclimatic conditions affecting the incidence of ALL in Iran and to draw a comparison between global and local regression models. MATERIALS AND METHODS In this ecological study, an exploratory-etiologic multiple-group method has been adopted to investigate all children under 15 years of age with ALL in Iran during 2006-2014. Data analysis was performed using Mann Whitney U, Pearson correlation coefficients (PCCs), Global Moran's I, Optimized hotspot analysis (OHSA), Global Poisson regression (GPR), Geographically Weighted Poisson Regression (GWPR) at a significant level of α = 0.05. RESULTS The cumulative incidence rate of ALL was estimated at 21,315 per 100,000 Iranian children under 15 years of age. The value of Global Moran's I index was estimated 0.338 and significant (<0.001 P-value). Coldspots were observed in north and northwest of Iran and hotspots were identified in south, southwest and mid-east of Iran. In the present study, Max Temperature of Warmest Month (MTWM) and Direct Normal Irradiation (DNI) were risk factors and Precipitation of the Coldest Quarter (PCQ) and Altitude (AL) were protective factors in the incidence of ALL, even though the non-stationarity of local coefficients and local t-values was clear. GWPR, by capturing and applying spatial heterogeneity and spatial autocorrelation, had a greater performance and goodness of fit than GPR. DISCUSSION ALL has created spatial clusters in Iran. The incidence of ALL is the result of synergistic interaction between environmental, infectious, geographical and genetic risk factors. It is recommended to use of local models in ecological studies.
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Affiliation(s)
- Sajjad Rahimi Pordanjani
- Epidemiology, Social Determinants of Health Research Center, Semnan University of Medical Sciences, Semnan, Iran; Epidemiology, Department of Epidemiology and Biostatistics, Semnan University of Medical Sciences, Semnan, Iran.
| | - Amir Kavousi
- Workplace Health Promotion Research Center, Department of Epidemiology, School of Public Health and Safety, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
| | - Babak Mirbagheri
- Center for Remote Sensing and GIS Research, Faculty of Earth Sciences, Shahid Beheshti University, Tehran, Iran.
| | - Abbas Shahsavani
- Air Quality Health and Climate Change Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran; Department of Environmental Health Engineering, School of Public Health and Safety, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
| | - Koorosh Etemad
- Epidemiology, Department of Epidemiology, School of Public Health and Safety Shahid Beheshti, University of Medical Sciences, Tehran, Iran.
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Pordanjani SR, Kavousi A, Mirbagheri B, Shahsavani A, Etemad K. Identification of high-risk and low-risk clusters and estimation of the relative risk of acute lymphoblastic leukemia in provinces of Iran during 2006-2014 period: A geo-epidemiological study. JOURNAL OF RESEARCH IN MEDICAL SCIENCES : THE OFFICIAL JOURNAL OF ISFAHAN UNIVERSITY OF MEDICAL SCIENCES 2021; 26:18. [PMID: 34084197 PMCID: PMC8106411 DOI: 10.4103/jrms.jrms_662_20] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Revised: 01/08/2020] [Accepted: 09/18/2020] [Indexed: 11/05/2022]
Abstract
BACKGROUND The present study was conducted to determine the epidemiological status, identify high-risk and low-risk clusters, and estimate the relative risk (RR) of acute lymphoblastic leukemia (ALL) in provinces of Iran. MATERIALS AND METHODS This is an ecological study carried out using an Exploratory Multiple-Group design on 3769 children under 15 years of age with ALL from 2006 to 2014. Data analysis was performed using Mann-Whitney U, Global Moran's I and Kuldorff's purely spatial scan statistic tests at a significance level of 0.05. RESULTS The average annual incidence rate of ALL during 2006-2014 period was 2.25/100,000 children under 15 years of age. The most likely high-risk cluster with log-likelihood ratio (LLR) =327.47 is located in the southwestern part of Iran with a radius of 294.93 km and a centrality of 30.77 N and 50.83 E, which contained 1276 patients with a RR of 2.56. It includes Fars, Bushehr, Kohgiluyeh and Boyer-Ahmad, Khuzestan and Chahar Mahall and Bakhtiari provinces. On the other hand, the most likely low-risk cluster with 517 patients, and a RR 0.49 and LLR = 227.03 was identified in the northwestern part of Iran with a radius of 270.38 km and a centrality of 37.25 N and 49.49 E. It includes Zanjan, Qazvin, Gilan and East Azerbaijan, Ardabil, Alborz and Tehran provinces. CONCLUSION High-risk clusters were observed in Southwestern, central, and eastern Iran, while low-risk clusters were identified in Northern and Western Iran.
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Affiliation(s)
- Sajjad Rahimi Pordanjani
- Department of Epidemiology, School of Public Health and Safety, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Amir Kavousi
- Workplace Health Promotion Research Center, Department of Epidemiology, School of Public Health and Safety, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Babak Mirbagheri
- Center for Remote Sensing and GIS Research, Faculty of Earth Sciences, Shahid Beheshti University, Tehran, Iran
| | - Abbas Shahsavani
- Environmental and Occupational Hazards Control Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
- Department of Environmental Health Engineering, School of Public Health and Safety, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Koorosh Etemad
- Department of Epidemiology, School of Public Health and Safety, Shahid Beheshti University of Medical Sciences, Tehran, Iran
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Rahimi Pordanjani S, Kavousi A, Mirbagheri B, Shahsavani A, Etemad K. Temporal trend and spatial distribution of acute lymphoblastic leukemia in Iranian children during 2006-2014: a mixed ecological study. Epidemiol Health 2020; 42:e2020057. [PMID: 32777882 PMCID: PMC7871159 DOI: 10.4178/epih.e2020057] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2020] [Accepted: 07/29/2020] [Indexed: 01/01/2023] Open
Abstract
OBJECTIVES The present study investigated the spatiotemporal epidemiological status of acute lymphoblastic leukemia (ALL), the most common childhood cancer, in Iran. METHODS Using an exploratory mixed design, this ecological study examined 3,769 under-15 children with ALL recorded in the National Cancer Registry of Iran during 2006-2014. Data were analyzed using the Mann-Whitney U test, the Getis-Ord general G (GOGG) index, optimized hot spot analysis, and Pearson correlation coefficients (PCC) at a significance level of 0.05. RESULTS The average annual incidence of the disease was 2.25 per 100,000 under-15 children, and the cumulative incidence rate (CIR) was 21.31 per 100,000 under-15 children. Patients' mean age was 5.90 years (standard deviation, 3.68), and the peak incidence was observed among 2-year to 5-year-olds. No significant difference was found in mean age between boys and girls (p=0.261). The incidence of ALL was more common during spring and summer than in other seasons. The GOGG index was 0.039 and significant (p<0.001). Hot spots were identified in south, central, and eastern Iran and cold spots in the north and west of Iran. The PCC between the CIR and latitude was negative (r=-0.507; p=0.003) but that between the CIR and longitude was positive (r=0.347; p=0.055). CONCLUSIONS The incidence of ALL in Iranian children was lower than that observed in developed countries, but showed an increasing trend. It can be argued that the incidence of ALL is due to synergistic interactions between environmental, infectious, geographical, and genetic risk factors.
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Affiliation(s)
- Sajjad Rahimi Pordanjani
- Department of Epidemiology, School of Public Health and Safety, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Amir Kavousi
- Department of Epidemiology, School of Public Health and Safety, Shahid Beheshti University of Medical Sciences, Tehran, Iran.,Workplace Health Promotion Research Center, School of Public Health and Safety, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Babak Mirbagheri
- Center for Remote Sensing and GIS Research, Faculty of Earth Sciences, Shahid Beheshti University, Tehran, Iran
| | - Abbas Shahsavani
- Environmental and Occupational Hazards Control Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran.,Department of Environmental Health Engineering, School of Public Health and Safety, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Koorosh Etemad
- Department of Epidemiology, School of Public Health and Safety, Shahid Beheshti University of Medical Sciences, Tehran, Iran
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Goujon S, Kyrimi E, Faure L, Guissou S, Hémon D, Lacour B, Clavel J. Spatial and temporal variations of childhood cancers: Literature review and contribution of the French national registry. Cancer Med 2018; 7:5299-5314. [PMID: 30230715 PMCID: PMC6198217 DOI: 10.1002/cam4.1774] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2018] [Revised: 07/19/2018] [Accepted: 08/21/2018] [Indexed: 12/26/2022] Open
Abstract
BACKGROUND Significant increases in childhood cancer incidence since the 1970s have been consistently reported worldwide, but the persistence of the increase on recent periods is discussed. No conclusion can be drawn concerning the spatial variations of childhood cancer, either. This study is an in-depth investigation of the spatial and temporal variations of childhood cancer in France. An extensive review of all the studies published since 2000 on those issues is provided. METHODS The study included 25 877 cases of childhood cancer registered nationwide over 2000-2014. The spatial heterogeneity (overdispersion, autocorrelation, overall heterogeneity) was tested, on two geographic scales, and two spatial scan methods were used to detect clusters of cases. The annual average percent change (AAPC) in incidence rate was estimated with Poisson regression models, and joinpoint analyses were considered. RESULTS Glioma and non-Hodgkin lymphoma cases exhibited some spatial heterogeneity and two large clusters were detected. Overall, the incidence rate of childhood cancer was stable over 2000-2014 (AAPC = -0.1% [-0.3%; 0.2%]). A log-linear positive trend was significantly evidenced for gliomas other than pilocytic astrocytomas (AAPC = 1.8% [0.9%; 2.7%]), with some suggestion of a leveling-off at the end of the period, while Burkitt lymphoma and germ cell tumor incidence rates decreased (AAPC = -2.2% [-3.8%; -0.5%] and AAPC = -1.9% [-3.4%; -0.3%], respectively). No spatial heterogeneity or significant time variation was evidenced for other cancers. CONCLUSION Several types of childhood cancer displayed some spatial heterogeneity and two large clusters were detected, the origins of which are to be investigated and might include differences in case ascertainment. Overall, the results do not support a sustained increase in incidence rates of childhood cancer in recent years.
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Affiliation(s)
- Stéphanie Goujon
- Epidémiologie des Cancers de l'enfant et de l'adolescent Team (EPICEA)UMR 1153 Epidemiology and Biostatistics Sorbonne Paris Cité Research Center (CRESS)InsermVillejuifFrance
- Sorbonne Paris CitéParis Descartes UniversityParisFrance
- French National Registry of Childhood Hematological Malignancies (RNHE)VillejuifFrance
| | - Evangelia Kyrimi
- Epidémiologie des Cancers de l'enfant et de l'adolescent Team (EPICEA)UMR 1153 Epidemiology and Biostatistics Sorbonne Paris Cité Research Center (CRESS)InsermVillejuifFrance
- Sorbonne Paris CitéParis Descartes UniversityParisFrance
| | - Laure Faure
- Epidémiologie des Cancers de l'enfant et de l'adolescent Team (EPICEA)UMR 1153 Epidemiology and Biostatistics Sorbonne Paris Cité Research Center (CRESS)InsermVillejuifFrance
- Sorbonne Paris CitéParis Descartes UniversityParisFrance
- French National Registry of Childhood Hematological Malignancies (RNHE)VillejuifFrance
| | - Sandra Guissou
- Epidémiologie des Cancers de l'enfant et de l'adolescent Team (EPICEA)UMR 1153 Epidemiology and Biostatistics Sorbonne Paris Cité Research Center (CRESS)InsermVillejuifFrance
- Sorbonne Paris CitéParis Descartes UniversityParisFrance
- French National Registry of Childhood Solid Tumors (RNTSE)Faculté de MédecineCHU NancyVandoeuvre‐lès‐NancyFrance
| | - Denis Hémon
- Epidémiologie des Cancers de l'enfant et de l'adolescent Team (EPICEA)UMR 1153 Epidemiology and Biostatistics Sorbonne Paris Cité Research Center (CRESS)InsermVillejuifFrance
- Sorbonne Paris CitéParis Descartes UniversityParisFrance
| | - Brigitte Lacour
- Epidémiologie des Cancers de l'enfant et de l'adolescent Team (EPICEA)UMR 1153 Epidemiology and Biostatistics Sorbonne Paris Cité Research Center (CRESS)InsermVillejuifFrance
- Sorbonne Paris CitéParis Descartes UniversityParisFrance
- French National Registry of Childhood Solid Tumors (RNTSE)Faculté de MédecineCHU NancyVandoeuvre‐lès‐NancyFrance
| | - Jacqueline Clavel
- Epidémiologie des Cancers de l'enfant et de l'adolescent Team (EPICEA)UMR 1153 Epidemiology and Biostatistics Sorbonne Paris Cité Research Center (CRESS)InsermVillejuifFrance
- Sorbonne Paris CitéParis Descartes UniversityParisFrance
- French National Registry of Childhood Hematological Malignancies (RNHE)VillejuifFrance
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Konstantinoudis G, Kreis C, Ammann RA, Niggli F, Kuehni CE, Spycher BD. Spatial clustering of childhood leukaemia in Switzerland: A nationwide study. Int J Cancer 2017; 141:1324-1332. [DOI: 10.1002/ijc.30832] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2017] [Revised: 05/24/2017] [Accepted: 05/31/2017] [Indexed: 12/18/2022]
Affiliation(s)
| | - Christian Kreis
- Institute of Social and Preventive Medicine (ISPM), Faculty of Medicine, University of Bern Switzerland
| | - Roland A. Ammann
- Department of Paediatrics InselspitalBern University Hospital, University of Bern Switzerland
| | - Felix Niggli
- Department of Oncology, University Children's Hospital Zurich Switzerland
| | - Claudia E. Kuehni
- Institute of Social and Preventive Medicine (ISPM), Faculty of Medicine, University of Bern Switzerland
| | - Ben D. Spycher
- Institute of Social and Preventive Medicine (ISPM), Faculty of Medicine, University of Bern Switzerland
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Ortega-García J, López-Hernández F, Cárceles-Álvarez A, Santiago-Rodríguez E, Sánchez A, Bermúdez-Cortés M, Fuster-Soler J. Analysis of small areas of paediatric cancer in the municipality of Murcia (Spain). ANALES DE PEDIATRÍA (ENGLISH EDITION) 2016. [DOI: 10.1016/j.anpede.2015.04.012] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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Ortega-García JA, López-Hernández FA, Cárceles-Álvarez A, Santiago-Rodríguez EJ, Sánchez AC, Bermúdez-Cortes M, Fuster-Soler JL. [Analysis of small areas of pediatric cancer in the municipality of Murcia (Spain)]. An Pediatr (Barc) 2015; 84:154-62. [PMID: 26164678 DOI: 10.1016/j.anpedi.2015.04.021] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2015] [Revised: 03/23/2015] [Accepted: 04/02/2015] [Indexed: 12/20/2022] Open
Abstract
INTRODUCTION Occasionally, primary care pediatricians notice the presence of small clusters of pediatric cancer (PC), but are often frustrated by the findings after statistical analysis. The study of small areas in spatial epidemiology has led to advances in identifying clusters and the environmental risk factors involved. The purpose of this study was to describe the PC incidence and the spatial distribution at the minimum level of disaggregation possible in Murcia, presenting the first urban municipality map of PC in Spain. MATERIALS AND METHODS A population-based descriptive study was conducted on the PC cases diagnosed in children younger than 15 years, between 1998 and 2013 in the municipality of Murcia. Cases were classified by sex, age group, and tumor type. Coordinates of home addresses at the time of diagnosis were assigned to each case, and spatial and spatio-temporal analyses were carried out at the level of census tracts, using FleXScan and SatScan. RESULTS A total of 155 cases of PC were diagnosed during this period. The overall incidence of PC (138/10(6) of children under the age of 15) and the incidence for individual tumor types were within the expected ranges for Europe. A spatio-temporal cluster of Hodgkin lymphoma was identified. CONCLUSIONS Small area analysis of PC cases may be a useful tool for the identification of PC clusters, which would allow for the generation of hypotheses regarding disease etiology, as well as developing urban models for environmental surveillance of PC.
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Affiliation(s)
- J A Ortega-García
- Unidad de Salud Medioambiental Pediátrica, Servicio de Pediatría, Laboratorio de Entorno y Salud Humana, Instituto de Investigación Biosanitaria de la Región de Murcia (IMIB), Hospital Clínico Universitario Virgen de la Arrixaca, Murcia, España.
| | - F A López-Hernández
- Departamento de Métodos Cuantitativos e Informáticos, Universidad Politécnica de Cartagena, Murcia, España
| | - A Cárceles-Álvarez
- Unidad de Salud Medioambiental Pediátrica, Servicio de Pediatría, Laboratorio de Entorno y Salud Humana, Instituto de Investigación Biosanitaria de la Región de Murcia (IMIB), Hospital Clínico Universitario Virgen de la Arrixaca, Murcia, España
| | - E J Santiago-Rodríguez
- Unidad de Salud Medioambiental Pediátrica, Servicio de Pediatría, Laboratorio de Entorno y Salud Humana, Instituto de Investigación Biosanitaria de la Región de Murcia (IMIB), Hospital Clínico Universitario Virgen de la Arrixaca, Murcia, España
| | - A C Sánchez
- Unidad de Salud Medioambiental Pediátrica, Servicio de Pediatría, Laboratorio de Entorno y Salud Humana, Instituto de Investigación Biosanitaria de la Región de Murcia (IMIB), Hospital Clínico Universitario Virgen de la Arrixaca, Murcia, España
| | - M Bermúdez-Cortes
- Sección de Oncología y Hematología Pediátricas, Hospital Clínico Universitario Virgen de la Arrixaca, Murcia, España
| | - J L Fuster-Soler
- Sección de Oncología y Hematología Pediátricas, Hospital Clínico Universitario Virgen de la Arrixaca, Murcia, España
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Siangphoe U, Wheeler DC. Evaluation of the performance of smoothing functions in generalized additive models for spatial variation in disease. Cancer Inform 2015; 14:107-16. [PMID: 25983545 PMCID: PMC4415687 DOI: 10.4137/cin.s17300] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2014] [Revised: 01/14/2015] [Accepted: 01/22/2015] [Indexed: 12/28/2022] Open
Abstract
Generalized additive models (GAMs) with bivariate smoothing functions have been applied to estimate spatial variation in risk for many types of cancers. Only a handful of studies have evaluated the performance of smoothing functions applied in GAMs with regard to different geographical areas of elevated risk and different risk levels. This study evaluates the ability of different smoothing functions to detect overall spatial variation of risk and elevated risk in diverse geographical areas at various risk levels using a simulation study. We created five scenarios with different true risk area shapes (circle, triangle, linear) in a square study region. We applied four different smoothing functions in the GAMs, including two types of thin plate regression splines (TPRS) and two versions of locally weighted scatterplot smoothing (loess). We tested the null hypothesis of constant risk and detected areas of elevated risk using analysis of deviance with permutation methods and assessed the performance of the smoothing methods based on the spatial detection rate, sensitivity, accuracy, precision, power, and false-positive rate. The results showed that all methods had a higher sensitivity and a consistently moderate-to-high accuracy rate when the true disease risk was higher. The models generally performed better in detecting elevated risk areas than detecting overall spatial variation. One of the loess methods had the highest precision in detecting overall spatial variation across scenarios and outperformed the other methods in detecting a linear elevated risk area. The TPRS methods outperformed loess in detecting elevated risk in two circular areas.
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Affiliation(s)
- Umaporn Siangphoe
- Department of Biostatistics, Virginia Commonwealth University, Richmond, VA, USA
| | - David C. Wheeler
- Department of Biostatistics, Virginia Commonwealth University, Richmond, VA, USA
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Investigating the relationship between mortality from respiratory diseases and childhood acute lymphoblastic leukaemia in Hungary. Pathol Oncol Res 2014; 21:53-7. [PMID: 24806976 DOI: 10.1007/s12253-014-9786-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/21/2013] [Accepted: 04/20/2014] [Indexed: 10/25/2022]
Abstract
Our aim was to investigate the ecological association between death from infectious disease of the respiratory system and the risk of acute lymphoid leukaemia (ALL) in children aged less than 7 years. Poisson regression analyses were carried out using overall data and gender-specific models. The study included 176 cases (92(52.3 %) boys and 84 (47.7 %) girls) of ALL in those aged 0-6 years in South Hungary. Eight cases were diagnosed before the age of 1 year. A significant risk of ALL disease was observed with higher levels of mortality from the chronic respiratory diseases (p = 0.035) and pneumonia (p = 0.010) among children aged 2-5 years (Odds Ratio for trend was 1.001 and 95%CI [1.000-1.002] and Odds ratio for trend was 1.013 and 95%CI [1.003-1.023], respectively). Significantly increased risk of childhood ALL was detected among children under 1 year of age residing in areas around birth with higher levels of mortality from influenza (Odds Ratio (OR) for trend was 1.05; 95%CI [1.01-1.09]; p = 0.012). This risk was also detected in girls (p < 0.001), but not in boys (p = 0.43). Our findings provide new evidence that will help to understand the different pattern of female and male childhood ALL occurrence , but further studies are needed using detailed individual medical history to clarify the role of influenza and other infectious diseases in the etiology of childhood ALL and to explain gender-specific effects.
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