Lifestyle related risk factors of non-occupational chronic diseases for workers using decision tree

Introduction
The purposes of this study were to identify the lifestyle related risk factors and high risk group for 5 non-occupational diseases (hypertension, liver disease, hyperlipidemia, diabetes, kidney disease).

Methods
The data for this study was collected from the 2007 annual physical examination of 293,144 workers from 11,210 workplaces conducted by the Korean Industrial Health Association. The methods for analysis were Chi-square test for analyzing the association between non-occupational diseases and workers' characteristics and lifestyle, logistic regression analysis for identifying the risk factors affecting diseases, and data mining for identifying the high risk group for diseases.

Results
Risk factors for non-occupational diseases were male worker aged over 40, production work, meat-based diet, excessive alcohol drinking (drink more than once a week), no-smoking for hypertension; male worker aged over 40, production work, vegetable-based diet, excessive drinking, current smoking for liver disease; male worker aged over 40, production work, meat-based diet, excessive drinking, past and current smoking for hyperlipidemia; male worker aged over 40, excessive drinking, current smoking for diabetes; and female worker aged over 40, production work, current smoking, and no-exercise for kidney disease. High risk group for non-occupational disease were age over 40, excessive drinking for hypertension; male who drinks more than once a week for liver disease; age over 40, and past and current smoking for hyperlipideia; and age over 50 for diabetes and kidney disease.

Discussion
This study may provide basic information for the health promotion policy of the disease management for workers. And this study may also help decide the priority and importance in the health promotion program for workers based on comprehensive information obtained from database of workplace health record.