Morning and evening types: stress-related personality aspects

A group of 232 adult subjects was administered the Morningness-Eveningness Questionnaire to assess their individual circadian typology and a battery of questionnaires of personality and psychological and psychosomatic disorders (Beck Depression Inventory; Bortner Type A Scale; Eysenck Personality Questionnaire; Jenkins Activity Survey; Middlesex Hospital Questionnaire; Strelau Temperament Inventory). Significant correlations between circadian typology scores and data relative to personality, psychosomatic disorders, and stress-prone behaviour were found. Evening types reported psychological and psychosomatic disturbances more frequently and intensively than morning types, and showed more problems in coping with environmental and social demands. The relevance of the morningness-eveningness dimension for research on stress and cardiovascular diseases is discussed.