Morningness-eveningness (chronotype) indicates the preferred time of intellectual and physical activity. This cross-sectional study had two main aims. The first aim was to explore associations among chronotype, quality of life, and relationship quality. The second aim of this study was to examine whether the similarities or discrepancies in chronotype between male and female members of the couples were linked to relationship quality. Both members of 143 couples (mean age = 39.44; SD = 10.11y) living together for at least 6 months completed measures of chronotype, marital stress, relationship satisfaction, dyadic coping, satisfaction with life, health-related quality of life, and quality of sleep. Variable-oriented (correlational) and person-oriented (cluster-analytic) analyses were conducted. Variable-oriented analyses showed that morningness was linked to better mental health, and fewer insomnia problems, but less frequent (self-perceived) stress communication for both genders. The discrepancy between the couple's chronotype scores was positively related to the women's sexual and general life satisfaction and more frequent (self-perceived) supportive dyadic coping by the partner. Moreover, ANOVA results showed that Evening-type (E-type) women had the highest mean score on sexual life satisfaction. According to cluster-analytic investigation, couples consisting of two morning-type members had the least frequent stress communication. On the other hand, these couples had better sleeping quality with less insomnia symptoms than couples with two E-type members. In summary, the present findings demonstrate that morningness holds both advantages and disadvantages for both general aspects of life and also the quality of relationships.
Keywords: Morningness-eveningness; couples; dyadic coping; quality of life; relationship quality.