Stress-induced increases in interleukin-6 and fibrinogen predict ambulatory blood pressure at 3-year follow-up.
BACKGROUND
The biological mechanisms underlying the association between psychological stress and hypertension are poorly understood. Increased plasma concentrations of the inflammatory proteins interleukin-6 and fibrinogen are commonly reported both in hypertensive patients and in people subject to chronic psychological stress. Recent laboratory studies have also shown that acute psychological stress increases plasma interleukin-6 and fibrinogen concentrations in healthy individuals.


OBJECTIVE
To investigate the relationship between stress-induced inflammatory responses and blood pressure using a longitudinal design.


METHODS
Participants were 153 individuals from the Whitehall II cohort. Blood pressure, plasma interleukin-6 and fibrinogen were assessed in response to an acute laboratory stressor, and ambulatory blood pressure was monitored on a separate day. Three years later, a follow-up day of ambulatory blood pressure monitoring was carried out.


RESULTS
Individual differences in systolic pressure, fibrinogen and interleukin-6 stress responses predicted ambulatory blood pressure at the 3-year follow-up. Larger increases in ambulatory systolic pressure over the 3-year period were predicted by larger acute fibrinogen and interleukin-6 stress responses, independently of previous ambulatory blood pressure, acute blood pressure stress responses, age, sex, body mass and smoking.


CONCLUSIONS
Given the important roles of interleukin-6 and fibrinogen in hypertensive pathophysiology, these results indicate that psychological stress could promote hypertension through stimulating these inflammatory proteins.
Brydon
Lena
L
The Psychobiology Group, Department of Epidemiology and Public Health, University College London, UK.
Steptoe
Andrew
A
D001794:Blood Pressure; D018660:Blood Pressure Monitoring, Ambulatory; D015992:Body Mass Index; D005260:Female; D005340:Fibrinogen / Q000032:analysis*; D005500:Follow-Up Studies; D006801:Humans; D015850:Interleukin-6 / Q000097:blood*; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D013315:Stress, Psychological / Q000097:blood*
D015850:Interleukin-6; D005340:Fibrinogen