Methods: To evaluate the impact of job stress versus dietary and other lifestyle risk factors on development of subclinical atherosclerosis, 297 asymptomatic employees of Chinese ethnic (mean age 43.4±10.1 year) from San Francisco, USA (n=187) and Pan Yu, southern China (n=110) were studied, as part of the multicentre Chinese community atherosclerosis (CATHAY) study. Carotid IMT was measured by high resolution ultrasound on both common carotid arteries, using an offline verified automatic edge-detection and measurement software package. Self-administered questionnaires on job stress (Karaseks job demand-control-support model) and daily food consumption (food catalogue album) were
completed. To test the modern lifestyles - MBS hypothesis, 187 asymptomatic ‘healthy’ employees of Chinese ethnic having lived in San Francisco for 315 years were studied. Their mean age was 44.6±10.2 years and 86 were males. Body mass index (BMI) were calculated by weight (Kg)/Height (M)2 equation,
insulin resistance was assessed by fasting glucose level (>7.0mmol/l) and dyslipidaemia by the presence of low density lipoprotein cholesterol >4.1mmol/l, triglyceride >2.0mmol/l or total cholesterol >6.2mmol/l. Questionnaires on psychological stress (Siegrists effort-reward model) and daily food consumption (food catalogue album) were completed. MBS was identified by presence of 32 out of 4 markers, including obesity (BMI>28 in male and >25 in female), dyslipidaemia, insulin resistance and hypertension.

Results: Age, smoking, excessive fat intake and lack of job support, but not carbohydrate or protein intake, were positively correlated to carotid IMT (p<0.05). On stepwise logistic regression analyses, apart from age, high fat product consumption and lack of job support were independently associated with increased IMT, while moderate alcohol consumption was negatively related (Table 1):

MBS was present in 31.6%, with higher job stress score than subjects without MBS (p=0.035). On stepwise logistic analyses, age, male gender, high fat intake and inability to withdraw from work were significantly associated with MBS, but alcohol, frequent change of job/boss, job nature (job effort or shift duty) were not contributing (Table 2):

Conclusions: High fat intake (from deep fried food and dairy products), and lack of job support are important independent risk factors for atherosclerosis in the Chinese, but moderate alcohol consumption may be protective. In westernized Chinese, high fat intake, male gender and inability to withdraw from work define independent risk factors for development of metabolic syndrome, which eventually may lead to atherosclerosis.

Reference:

1. Woo KS, Chook P, Raitakari OT, McQuillan B, Celermajer DS. Westernization of Chinese adults and increased subclinical atherosclerosis. Arterioscl Throm Vasc Biol 1999;19:2487-2493.

2. Woo KS, Chook P, Liu BTY, Leung SF, Woo JLF, Feng JZ, Chan SW, Celermajer DS. Subclinical atherosclerosis and dietary patterns in modernizing Chinese: An east to west voyage. Circulation 1999;100:supp I-823.

3. Woo KS, Chan SW, Chook P, Lam CWK, Celermajer DA. Longer duration of westernization is associated with subclinical atherosclerosis in Chinese Americans. J Am Coll Cardiol 2001;37:Supp A-297A.

Foodnote:
CATHAY Study = Chinese Atherosclerosis study in the Aged and Young