Abstract:

Objective To analyze the relationship between the reference value of left ventricular posterior wall thickness (LVPW) of Chinese middle-aged and elderly people and geographical factors and to provide scientific evidences for establishing the uniform standard. Methods Reference values of LVPW of 3 543 Chinese healthy middle-aged and elderly people from 67 cities were collected. The correlation analysis method was adopted to investigate the relationship between the reference value and 18 geographical factors, including terrain, climate, soil, etc. Geographical factors that significantly correlated with the reference value were selected for conducting the multiple linear regression and BP neural network modeling. The spatial distribution map of the reference value of LVPW of Chinese middle-aged and elderly people was fitted by the inverse distance weight method. Results The reference value of LVPW of Chinese middle-aged and elderly people was significantly correlated with the longitude, altitude, percentage of sand in topsoil, percentage of silt in topsoil, total exchangeable capacity of topsoil, and alkalinity of topsoil. The simulation and prediction performance of BP neural network model was better than that of the multiple linear regression model. The spatial distribution map of the reference value of LVPW of Chinese middle-aged and elderly people showed a distribution feature of higher in the west and lower in the east. Conclusion If the geographical factors of a certain area are known, the reference value of LVPW of Chinese middle-aged and elderly people can be obtained by establishing the neural network model or plotting the spatial distribution map.

Key words: cardiac function, left ventricular posterior wall thickness, reference value, geographical factors, BP neural network