Geographic variations in cervical cancer risk in San Luis Potosí state, Mexico: A spatial statistical approach.
BACKGROUND
Worldwide, Cervical Cancer (CC) is the fourth most common type of cancer and cause of death in women. It is a significant public health problem, especially in low and middle-income/Gross Domestic Product (GDP) countries. In the past decade, several studies of CC have been published, that identify the main modifiable and non-modifiable CC risk factors for Mexican women. However, there are no studies that attempt to explain the residual spatial variation in CC incidence In Mexico, i.e. spatial variation that cannot be ascribed to known, spatially varying risk factors.


METHODS
This paper uses a spatial statistical methodology that takes into account spatial variation in socio-economic factors and accessibility to health services, whilst allowing for residual, unexplained spatial variation in risk. To describe residual spatial variations in CC risk, we used generalised linear mixed models (GLMM) with both spatially structured and unstructured random effects, using a Bayesian approach to inference.


RESULTS
The highest risk is concentrated in the southeast, where the Matlapa and Aquismón municipalities register excessive risk, with posterior probabilities greater than 0.8. The lack of coverage of Cervical Cancer-Screening Programme (CCSP) (RR 1.17, 95 % CI 1.12-1.22), Marginalisation Index (RR 1.05, 95 % CI 1.03-1.08), and lack of accessibility to health services (RR 1.01, 95 % CI 1.00-1.03) were significant covariates.


CONCLUSIONS
There are substantial differences between municipalities, with high-risk areas mainly in low-resource areas lacking accessibility to health services for CC. Our results clearly indicate the presence of spatial patterns, and the relevance of the spatial analysis for public health intervention. Ignoring the spatial variability means to continue a public policy that does not tackle deficiencies in its national CCSP and to keep disadvantaging and disempowering Mexican women in regard to their health care.
Geography Graduate Programme, Universidad Nacional Autónoma de México (UNAM), Ciudad de México, México. mteran@uaslp.mx.|Universidad Autónoma de San Luis Potosí (UASLP), Campus Poniente, 130 Av. Niño Artillero, Zona Universitaria, San Luis Potosí, S. L. P., 78210, Mexico. mteran@uaslp.mx.
Mónica
M
Terán-Hernández
Department of Environmental Epidemiology and Cancer, National Centre for Epidemiology, Carlos III Institute of Health (ISCIII), C/Monforte de Lemos 5, Pab. 12, 28029, Madrid, Spain.
Rebeca
R
Ramis-Prieto
Centre of Applied Research in Environmental and Health, Coordination of Innovation and Application in Science and Technology, Universidad Autónoma de San Luis Potosí (UASLP), Unidad de Posgrado 550 Av. Sierra Leona, Lomas 2ª sección, San Luis Potosí, S.L.P., 78210, Mexico.
Jaqueline
J
Calderón-Hernández
El Colegio Mexiquense, A.C. Ex-Hacienda Santa Cruz de los Patos, Zinacantepec, CP 51350, Mexico.
Carlos Félix
CF
Garrocho-Rangel
Faculty of Geography, Universidad Autónoma del Estado de México (UAEM), Cerro de Coatepec s/n Ciudad Universitaria, CP 50110, Toluca, Mexico.
Juan
J
Campos-Alanís
Regional Laboratory of Variability, Climate Change and Environmental Risk Assessment, Universidad Autónoma de San Luis Potosí (UASLP), Unidad de Posgrado 550 Av. Sierra Leona, Lomas 2ª sección, San Luis Potosí, S.L.P. 78210, Mexico.
José Antonio
JA
Ávalos-Lozano
Faculty of Social Sciences and Humanities, Universidad Autónoma de San Luis Potosí (UASLP), Campus Oriente, 101-A Av. Industrias, Fracc. Talleres, San Luis Potosí, S.L.P. 78399, Mexico.
Miguel
M
Aguilar-Robledo
Bayesian approach; Cervical cancer; Generalised lineal mixed models; México; San Luis Potosí; Spatial analysis
Stat Med. 2002 Feb 15;21(3):359-70
11813223
Salud Publica Mex. 2002 Jul-Aug;44(4):335-44
12216521
Int J Health Geogr. 2004 Feb 26;3(1):3
14987337
Environ Health Perspect. 2004 Jun;112(9):1016-25
15198922
Salud Publica Mex. 2005 Sep-Oct;47(5):342-50
16323527
J Health Econ. 2007 Mar 1;26(2):306-25
17010459
BMC Cancer. 2007 May 08;7:78
17488519
Rev Panam Salud Publica. 2008 Feb;23(2):135-43
18371285
Cancer Epidemiol Biomarkers Prev. 2008 Oct;17(10):2808-17
18843027
Health Place. 2009 Dec;15(4):1100-7
19576837
Eur J Cancer Prev. 2009 Sep;18(5):395-403
19609213
Salud Publica Mex. 2009;51 Suppl 2:s208-19
19967276
Salud Publica Mex. 2010 Sep-Oct;52(5):432-46
21031250
Eur J Cancer. 2012 Mar;48(5):743-8
21788130
Int J Health Geogr. 2011 Sep 26;10:51
21943079
Int J Environ Res Public Health. 2012 Jan;9(1):294-314
22470293
Int J Health Geogr. 2012 Nov 16;11:50
23153335
PLoS One. 2012;7(11):e48834
23155413
Spat Spatiotemporal Epidemiol. 2013 Mar;4:33-49
23481252
Eur J Cancer. 2013 Oct;49(15):3262-73
23751569
Health Place. 2013 Nov;24:30-43
24021921
Int J Cancer. 2014 Jul 1;135(1):109-16
24615258
Salud Publica Mex. 2013;55 Suppl 2:S235-40
24626700
Int J Cancer. 2015 Mar 1;136(5):E359-86
25220842
Health Place. 2014 Nov;30:134-44
25262491
Int J Environ Res Public Health. 2015 Nov 13;12(11):14490-504
26580637
Rev Panam Salud Publica. 2016 Feb;39(2):106-114
27754517
Biometrics. 1987 Sep;43(3):671-81
3663823