A multilevel analysis of place effects on body constitution

Abstract

Body constitution, according to Traditional Chinese Medicine (TCM), is an individual's personal state of health expressed in reference to body metabolism and susceptibility to pathogenic factors. From the TCM perspective, body constitution is transient in nature and disease may ensue when the inner harmony of a human body is disrupted in response to the external environment. Despite strong scientific basis of the TCM concept of body constitution, the effects of place or living environment on the body constitution have not been supported with much empirical evidence. The objective of this research is to investigate the place effect on the TCM concept of body constitution by means of multilevel models and health geography approach. This study purports to generalise place using actual geographical division at the level of street block group for hypothesis testing. The analysis was conducted on 3,277 patients who made their visits to the Kwong Wah Hospital in Hong Kong between 2009 and 2012 inclusive. The multilevel analysis also took simultaneous accounts of both individual-level (gender, age, BMI, type of housing) and area-level GIS-based (percent greenery, percent road surface, total road intersection, sky view factor, temperature, relative humidity, rainfall and social deprivation index) characteristics to explain the geographical variation of body constitution. The results based on a small community of Kowloon showed that place had a role in the outcome of body constitution. Spatial variability of body constitution among neighbourhoods involved a dynamic interplay between individual and environmental factors.