Application of artificial neural network in medical geochemistry.

For the evaluation of various adverse health effects of chemical elements occurring in the environment on humans, the comparison and linking of geochemical data (chemical composition of groundwater, soils, and dusts) with data on health status of population (so-called health indicators) play a key role. Geochemical and health data are predominantly nonlinear, and the use of standard statistical methods can lead to wrong conclusions. For linking such data, we find appropriate the use method of artificial neural networks (ANNs) which enable to eliminate data inhomogeneity and also potential data errors. Through method of ANNs, we are able to determine the order of influence of chemical elements on health indicators as well as to define limit values for the influential elements at which the health status of population is the most favourable (i.e. the lowest mortality, the highest life expectancy). For determination of dependence between the groundwater contents of chemical elements and health indicators, we recommend to create 200 ANNs. In further calculations performed for identification of order of influence of chemical elements as well as definition of limit values, we propose to work with median or mean values from calculated 200 ANNs. The ANN represents an appropriate method to be used for environmental and health data analysis in medical geochemistry.

Chemical composition of groundwater/drinking water and oncological disease mortality in Slovak Republic.

This study deals with the analysis of relationship between chemical composition of the groundwater/drinking water and the data on mortality from oncological diseases (MOD) in the Slovak Republic. Primary data consist of the Slovak national database of groundwater analyses (20,339 chemical analyses, 34 chemical elements/compounds) and data on MOD (17 health indicators) collected for the 10-year period (1994-2003). The chemical and health data were unified in the same form and expressed as the mean values for each of 2883 municipalities within the Slovak Republic. Pearson and Spearman correlation as well as artificial neural network (ANN) methods were used for analysis of the relationship between chemical composition of groundwater/drinking water and MOD. The most significant chemical elements having influence on MOD were identified together with their limit values (limit and optimal contents). Based on the results of calculations, made through the neural networks, the following eight chemical elements/parameters in the groundwater were defined as the most significant for MOD: Ca + Mg (mmol l-1), Ca, Mg, TDS, Cl, HCO3, SO4 and NO3. The results document the highest relationship between MOD and groundwater contents of Ca + Mg (mmol l-1), Ca and Mg. We observe increased MOD with low (deficit) contents of these three parameters of groundwater/drinking water. The following limit values were set for the most significant groundwater chemicals/parameters: Ca + Mg 1.73-5.85 mmol l-1, Ca 60.5-196.8 mg l-1 and Mg 25.6-35.8 mg l-1. At these concentration ranges, the mortality for oncological diseases in the Slovak Republic is at the lowest levels. These limit values are about twice higher in comparison with the current Slovak valid guideline values for the drinking water.

Chemical composition of groundwater and relative mortality for cardiovascular diseases in the Slovak Republic.

The study deals with the analysis of relationship between chemical composition of the groundwater/drinking water and the data on relative mortality for cardiovascular diseases (ReI) in the Slovak Republic. Primary data consist of the Slovak national database of groundwater analyses (20,339 chemical analyses, 34 chemical elements/compounds) and data on ReI collected for the 10-year period (1994-2003). The chemical and health data were unified in the same form and expressed as the mean values for each of 2883 municipalities within the Slovak Republic for further analysis. Artificial neural network was used as mathematic method for model data analysis. The most significant chemical elements having influence on ReI were identified together with their limit values (maximal acceptable, minimal necessary and optimal). Based on the results of calculations, made through the neural networks, the following ten chemical elements/parameters in the groundwater were defined as the most significant for ReI: Ca + Mg (mmol l(-1)), Ca, Mg, TDS, Cl, HCO3, SO4, NO3, SiO2 and PO4. The obtained results document the highest relationship between ReI and the groundwater contents of Ca + Mg (mmol l(-1)), Ca and Mg. Following limit values were set for the most significant groundwater chemicals/parameters: Ca + Mg 4.4-7.6 mmol l(-1), Ca > 89.4 mg l(-1) and Mg 42-78.1 mg l(-1). At these concentration ranges, the relative mortality for cardiovascular diseases in the Slovak Republic reaches the lowest levels. These limit values are about twice higher in comparison with the current Slovak valid guideline values for the drinking water.

Effect of spa therapy after intervertebral disc surgery in the cervical spine.

OBJECTIVE: The aim of this paper is to determine whether standard spa treatment significantly affects disability, functional status, and quality of life of patients after surgery of intervertebral discs in the cervical spine. MATERIAL AND METHODS: The study was performed in patients who underwent an artificial intervertebral disc replacement in the cervical spine.The study involved a group of 88 patients with mean age of 49.49 (range 32 to 74, standard deviation 9.12) while the experimental group consisted of 40 patients who underwent spa treatment with mean age of 49.35 (range 32 to 72, standard deviation 7.69). The control group was not treated by spa treatment, and consisted of 48 patients with mean age of 49.6 (range 36 to 74, standard deviation 8.73). These patients underwent standard medical rehabilitation at rehabilitation departments.Dysfunction of the cervical spine was scaled according to The Neck Disability Index (NDI). Functional status of patients was evaluated by Pulses Profile, and quality of life was evaluated by test of the quality of life according to Spitzer. RESULTS: The statistical evaluation parameter for NDI, Pulses and Spitzer found significant difference at the significance level of 0.01, suggesting that experimental group of patients who received spa treatment during follow-up examination had significantly better results in comparison with the control group. CONCLUSION: As a result of this study we have concluded that after implantation of the artificial intervertebral disc replacement in the cervical spine it is appropriate to recommend spa treatment for its positive effect on disability, functional status, and quality of life (Tab. 3, Fig. 3, Ref. 24).