TITLE:
Application of Multivariate Geostatistics in Environmental Epidemiology: Case Study from Houston, Texas
AUTHORS:
Faye Anderson
KEYWORDS:
Multivariate Geostatistics, COPD, CVD, Harris, Houston, PM2.5, Ozone
JOURNAL NAME:
Journal of Geoscience and Environment Protection,
Vol.4 No.4,
April
28,
2016
ABSTRACT: This
study represents an example of investigating the associations between the joint
exposure to ozone (O3) and particulate matter of sizes less than or equal to
2.5 micrometers in aerodynamic diameter (PM2.5) and cardiovascular disease
(CVD) emergency room (ER) visits and chronic obstructive pulmonary disease
(COPD) ER visits using multivariate geostatistics in Houston, Texas, from 2004
to 2009. Analyses showed lack of strong pair-wise association among the
predictors of O3, PM2.5, wind speed, relative humidity, and temperature.
Whereas CVD and COPD ER visits exhibited a strong positive correlation. Both
outcomes drastically increased from 2006 possibly due to immigration from
neighboring locations. Parametric testing showed that the data differed
significantly between the years. Multivariate multiple regression results on
the 2009 data showed that PM2.5, relative humidity, and temperature were
significant to both CVD and COPD ER visits. Codispersion coefficients were
constant which justified the assumption of intrinsic correlation. That is, our
predictors had strong influence on the spatial variability of CVD and COPD ER
visits. This multivariate geostatistics approach predicted an increase of 34%
in CVD ER visits and 24% increase in COPD ER visits, which calls for more
attention from policy makers. The use of multivariate geostatistics analyses
enabled us to successfully detect the effects of risk factors on both outcomes.