Alcohol, personality and predisposition to essential hypertension.

The nature of the relationship between alcohol, personality and blood pressure levels was examined in 491 working men who completed detailed questionnaires which included Eysenck's personality inventory. Alcohol had an effect on systolic blood pressure levels independent of all other factors studied. However, in 152 non-smoking moderate to heavy drinkers (greater than 18 g ethanol per day) the extroversion/introversion trait was the most significant predictor of systolic blood pressure levels, and in introverted drinkers the prevalence of hypertension (greater than or equal to 140 mmHg systolic or greater than or equal to 90 mmHg diastolic) was three times that of extroverted drinkers and nine times that of teetotallers. This association between introversion and 'hypertension' was not seen in drinkers who also smoked cigarettes. The interactions between environmental stimuli (alcohol, smoking) and presumably genetically determined personality characteristics may have an important bearing on concepts of essential hypertension and point to new approaches for investigation.