Social influences and cardiovascular risk factors as determinants of plasma fibrinogen concentration in a general population sample of middle aged men.

Abstract
OBJECTIVE--To analyse the relation between fibrinogen concentration and social class and other social factors found to be related to mortality. The results regarding cardiovascular disease are unpublished, as yet. DESIGN--Cross sectional population study. SETTING--City of Gothenburg, Sweden. SUBJECTS--639 Men from a population sample of 1016 men aged 50 in 1983. They were all employed and had no history of myocardial infarction or stroke. Fibrinogen values were available for all of them. MAIN OUTCOME MEASURE--Fibrinogen concentration in relation to socioeconomic state according to occupation, and other social influences determined as number of people in the household and scores of social activities and activities in and outside the house. RESULTS--Men with low scores for activities at home had a mean plasma fibrinogen concentration of 3.34 g/l (95% confidence interval 3.21 to 3.47), whereas those with an intermediate score had a mean concentration of 3.16 (3.00 to 3.32) g/l and those with a high score 3.02 (2.95 to 3.10) g/l. Similar inverse relations were noted for the two other activity scores and for occupational class (class 1 being unskilled and semiskilled workers and class 5 professionals and executives) and the number of people in the household. Smoking exerted a strong influence on fibrinogen concentration, the relations between fibrinogen concentration and social factors being evident only in non-smokers. The mean difference in fibrinogen value between the non-smokers with the lowest activity scores at home and those with the highest scores was 0.36 (0.19 to 0.54) g/l, and similar differences were seen for the two other activity scores. Multiple regression analyses showed smoking, body mass index, the sum of all activities (inverse relation), and diabetes to be independently associated with fibrinogen value, whereas occupational class (p = 0.81) and the number of people in the household (p = 0.09) were not. CONCLUSIONS--Psychosocial influences seem to influence the coagulation system in the body in a way that is associated with cardiovascular disease and premature death.