The Relationship Between Neuroendocrine Biomarkers And Occupational Stress And Its Induced Essential Hypertension

一.The relation between neuroendocrine biomarkers and occupational stress Objective:Analysis on the relation between occupational stress and biomarkers of sympathetic-adrenal system (SAM),the hypothalamus-pituitary-adrenal cortex system (HPA) and renin-angiotensin (RAAS).Screen objective evaluation of occupational stress. And reveal neuroendocrine mechanisms of chronic occupational stress.Methods:Three occupational groups, including the physical (railway attendants 292), mental (general officers 130) and the mix (railway policemen 100) were cluster sampled as objection. Their occupational stress and stress factors were evaluated by occupational stress (OSI-R) scale, A-type behavior, the state-trait anxiety (STAI).By random sampling method,90 railway policemen,180 attendants and 90 officers were drawn from field survey. And their plasma neuroendocrine biomarkers of three stress pathways were detected by radioimmunoassay. Control the occupation and length of service, partial correlation analyze on neuroendocrine biomarkers and occupational stress.Covariance modern analyze on neuroendocrine biomarker concentration of different level of stress and stress factor. Analyze on covariance model of the interaction on neuroendocrine biomarker of occupational stress and stress factors.And analyze the risk factors of neuroendocrine biomarkers elevated by Logistic Regression Analysis.The interactions of three neuroendocrine pathways to the occupational stress also were analyzed by relevant and Logistic regression model.Results:1.The relation between SAM system biomarker (Catecholamines, including Adrenaline, Norepinephrine and Dopamine) and occupational stressAdrenaline (Ad) was occupational stress scores (r=0.252, p=0.000).Most sub-entries, A-type behavior and state-trait anxiety were positively related to Ad. Norepinephrine (NE) was positively correlated to occupational stress scores (r 0.160, p=0.010), including occupation tasks, stress response and trait anxiety. Dopamine (DA) was not related to occupational stress or stress factors.Ad in high and medium score groups of occupational stress and sub-entries was higher than in low group. NE in high score group of total occupational stress was higher than in low group.DA in n high score group of total occupational stress was lower than in medium group. The interaction by occupational stress and state anxiety was the existence to Ad interaction (F=3.061,P=0.043).There were no interactions on NE or DA between occupational stress and stress factors.Length of service, occupational stress and the state of anxiety were into the regression equation of Ad, OR=0.696, 2.031 and 1.769.The trait anxiety was into the regression equation of NE increased, OR=1.882.Occupational stress into the regression equation of DA increased, OR =0.400.2.The relation between HPA axis biomarkers (cortisol) and occupational stressCortisol (COR) was positively correlated to state anxiety (r=0.125,p=0.017). The correlations between COR and occupational stress and other stress factors were not significant. COR in the high score groups of occupational stress and stress were higher than in the low group.COR in different level of A-type behavior and state-trait anxiety was no significant differences.There was not interaction effect on COR between occupational stress and stress factors.Occupational stress was into the regression equation of COR, OR=1.923.3.The relation between RAS system biomarker (renin activity, angiotensinⅡand aldosterone) and occupational stressRenin activity (PRA),AngiotensinⅡ(AngⅡ)and Aldosterone (ALD) were not related to occupational stress and most stress factors. PRA and AngⅡamong different score of occupational stress and stress factors were no significant differences.ALD in high score group of stress response was higher than in medium group.There were no interactions on PRA, AngⅡor ALD between occupational stress and stress factors. Marriage (married) into the regression equation of PRA increased, the OR=2.325.The length of service and trait anxiety were both into the regression equation of Ang II, OR=0.427,1.183.A-type behavior was into the regression equation of ALD increased, OR=3.060.4.The interaction among three neuroendocrine pathways biomarkers on the occupational stress.In the high occupational stress group, COR of HPA axis and PRA,ALD of RASS system had positive correlation (r=0.251 and 0.334).In low occupational stress group,the correlation coefficients between these three pathways were no statistic significant. Ad of SAM system with ALD of RASS system, NE with ALD, had interaction effect on occupational stress, the OR of interaction were 2.770 and 2.780.Ad elevated, trait anxiety and career were into the regression equation of occupational stress, the OR were 3.178,4.161 and 3.069, respectively.二.The relation between stress biomarkers and essential hypertensionObjective:Analyze on the relation of stress biomarkers and essential hypertension. Reveal neuroendocrine mechanisms of essential hypertension by chronic occupational stress.Methods:On the population, investigate hypertension risk factors (smoking, alcohol consumption, physical activity, salt diet, the genetic history of hypertension, overweight and obesity).Test their blood pressure, blood glucose and lipid. Compared the neuroendocrine biomarker concentrations of different prevalence of hypertension by age stratified. Rank correlation analyze on the biomarkers and blood pressure. Control of hypertension risk factors, covariance analyze of the biomarkers in different blood pressure. And compared biomarker concentration of hypertension and blood pressure between high and low stress groups. Analyze on the biomarkers in hypertensive patients with risk factors.Results:1.The relation between SAM system neuroendocrine biomarker (catecholamines) and hypertension and blood pressureCatecholamine in hypertensive patients with normal blood pressure was no significant difference.Age stratified, only adrenaline (Ad) in the hypertensive group, the older group had less concentration, and the difference was statistically significant. Ad, NE and DA levels increased with blood pressure, first decreased and then increased, which are the lowest concentration in normal values and mild hypertension group.n high occupational stress, the concentration of Ad in normal blood pressure group was higher than in hypertensive group of low occupational tress. In high occupational stress, the concentration of DA in hypertension group was lower than in the hypertension and normal group of low stress.Hypertensive patients with history of hypertension, overweight and obese, had higher NE concentration than those without exposure to these factors.Other hypertension risk factors had no significant effects on catecholamines.2.The relatioan between HPA neuroendocrine biomarkers (cortisol) and hypertension and blood pressureCortisol (COR) between in hypertension and abnormal blood pressure was no significant difference. COR in different age groups also had no significant difference. COR concentration increased with the blood pressure.The moderate and above hypertension group had higher concentration of COR than normal blood pressure group.In high stress COR of hypertensive and normal blood pressure were higher than in low stress with normal blood pressure.The hypertension factors had no statistical significance affects on the COR.3.The relation between RAAS neuroendocrine biomarkers (renin activity, angiotensinⅡand aldosterone) and hypertension and blood pressureRenin activity (PRA),AngiotensinⅡ(AngⅡ) and Aldosterone (ALD) in hypertension were no significant difference to abnormal blood pressure. In hypertension patients, older had lower PRA,AngⅡconcentrations than the young, the difference was statistically significant. But ALD in the age groups were no significant differences. PRA,AngⅡin different blood pressure were no significant differences. ALD was positive related to blood pressure (r=0.161,p=0.008).Moderate and above hypertension had the highest ALD concentration, followed by normal high and normal blood pressure groups.In high and low occupational stress the RA, Ang II and ALD were no different between hypertensive and non-hypertensive group.In high stress the ALD of hypertension was higher of hypertension and normal groups in low stress, the difference was significant. In hypertension patient, high salt diet group had higher ALD than the normal diet group. Other risk factors of hypertension had no statistically significant effects on PRA, Ang II and ALD.Conclusion:Unde the conditions of this study, the conclusions were following:1.SAM system was involved in the neuroendocrine response to chronic stress, the extent which the system's activity reflected to the occupational stress was maily related to the biomarkers'secretion; In the long-term of chronic stress, adrenaline (Ad) was better to reflect the load level of occupational stress, DA and other monoamine neurotransmitter may have depletion phenomenon; the DA should be combined with Ad to reflect load level as a professional and objective evaluation.2.Catecholamine secretion level increased with occupational stress, but the extent of the increase was different.The increase in the medium of occupational stress was the most significant.But in the highest stress levels catecholamine reduced or the increase was not significant.SAM system should be a different regulatory role in different chronic stress stage.3.HPA axis neuroendocrine biomarker cortisol (COR) had close relationship with occupational stress.So it should be used as an indicator of occupational stress assessment. HPA axis was an important way of involving in the chronic stress.4.Renin activity(PRA),angiotensinⅡ(AngⅡ) and aldosterone (ALD) of RAAS system, had less relation to occupational stress.And they have many other factors.So they shoule be reflected reference to occupational stress.5.The neuroendocrine biomarkers were affected not only by occupational stress, but also by other stress factors in vivo.So the neuroendocrine biomarkers should always work with the analysis based on psychological parameters and data to measure occupational stress.6.In the high occupational stress, SAM, HPA axis and the RAAS system were mutual ties and influence in the regulation of the neuroendocrine system response to occupational stress.7.Long-term chronic job stress caused the activity increased of SAM, HPA, and RAAS stress system. Then Norepinephrine (NE),Cortisol (COR) and Aldosterone (ALD) secreted increase, which induced and contributed to the occurrence and development of essential hypertension. If the hypertension risk factors (the genetic history of hypertension, overweight and obesity, high salt diet) existed, activities of AE and ALD were more significant.