Abstract
Objectives: To explore the relationship between shiftwork duration and metabolic risk fac-tors on cardiovascular disease in shiftworkers. Methods: The study subjects comprised of 226 nurses, from a hospital, and 130 male work-ers, from a diaper and feminine hygienic material manufacturing firm The mean ages of the male workers and nurses were 29 and 28.5 years, respectively The fasting blood sugar, serum cholesterol, blood pressure, height and weight, waist and hip circumferences (only in nurses),and number of step for a shift as indices of physical activity were measured Using the Korean version of Karasek' s job contents questionnaire, the job stress was assessed information about the number of years worked, duration ofr shiftwork, and past medical and behavioral histories, including smoking, were obtained by self-administrated questionnaires Linear regression analy-ses were performed, to show the relationships between shiftwork duration and metabolic risk factors, using simple and multivariate models, adjusted for age, smoking, job strain and physical activity The following criteria were defined hypertension as a $SBP\ge 160$ or a $DBP\ge 90mmHg$ at least once, hypercholesterolemia, as a serum total $cholesterol\ge 240mg/dl$, obesity as BMI (Body Mass index) $\ge 25kg/m^2$ and central obesity as a WHR (Waist to Hip Ratio) $\ge$ 0.85;and the logistic regression analyses, according to years of shiftwork, were performed using Sim-pIe and adjusted models. Results The cholesterol and fasting blood sugar showed increasing trends, but without statisti-cal significances, according to the increase in shiftwork duration of the male workers, although, the increases in the blood pressure and BMI were statistically significant in the nurses, only the WHR showed a significant increase in relation to the shiftwork duration in the logistic regres-sion analyses, hypercholesterolemia and obesity showed significant increasing risks according to the number of years of shiftwork (OR=3.32 95%CI 1.27-8 72 and OR=3.21 95%CI 1.24-8.32respectively) in the male workers, but hypertension showed no significance in the nurses, only an increased central obesity was significant as a risk factor (OR=1 30 95%CI 1 05-1 62)Conclusions These results provide evidence of the associations between shiftwork and meta-bolic risk factors for cardiovascular disease, although healthy shiftworker effects might exist inour cross sectional study designKey Words Shiftwork, Blood sugar, Blood pressure, Obesity, Metabolic nsk factor
목적: 교대근무가 심혈관계 질환의 대사성 위험요인과 관련성을 가지고 있는지를 보고자 하였다. 방법: 1개 대학병원의 2 2 6명의 간호사 및 간호조무사, 134명의 제조업체 생산직 남성 근로자를 대상으로, 혈중 콜레스테롤, 혈압, 혈당, 비만지수(BMI) 및 중심성 비만지수(WHR) 등을 측정하여, 교대근무 기간에 대한 회귀분석 및 로지스틱 회귀분석을 시행하여 다음과 같은 결과를 얻었다. 결과: 간호사에서는 혈중 콜레스테롤, 혈당, 혈압 및 비만지수와 교대근무 기간사이에는 유의한 양의 관련성이 관찰되지 않았고, 중심성 비만지수( W H R )와는 유의한 양의 관련성을 나타내었으며, 교대근무 기간의 상승이 중심성 비만의 위험도를 유의하게 상승시켰다. 이는 연령, 직무스트레스 및 신체적 활동도를 보정한 다변량 분석에서도 동일하였다. 남성 근로자에서는 혈압, 공복시 혈당, 비만지수가 회귀분석에서 유의한 양의 연관성을 보였으며, 고콜레스테롤혈증 및 비만의 유의한 발생위험도의 상승을 보여주었다. 결론: 본 연구 결과는 교대근무가 심혈관계 질환의 대사성 위험요인을 증가시킬 수 있음을 시사하는 것이며, 본 연구의 단면적 연구디자인으로 인하여 발생할 수 있는‘건강 교대근로자 효과’를 극복하기 위한 전향적 연구의 필요성을 제기한다고 하겠다.