BACKGROUND: The international literature consistently shows that the psychosocial outcomes of the informal carers (caregivers) of chronically ill patients are influenced by factors such as personality traits and perceived social support, but few studies have investigated these variables in the caregivers of hemodialysed patients, and the reciprocal experience of chronicity.; METHODS: Fifty hemodialysed patients and their principal caregivers were recruited. They were administered specific questionnaires to evaluate their emotional stability and anxious/depressive reactions, the perceived burden related to the patients' condition, the quality of their family relationships and knowledge of the disease, and the degree of satisfaction with their lives. The study design was correlational and comparative. The data were analysed using Student's t test and Pearson's correlation.; RESULTS: The patients were significantly more anxious and depressed than their caregivers, and had a more negative perception of their family relationships; they also had significantly higher neuroticism scores. Although the caregivers showed good emotional stability and a relatively low level of perceived burden, they stated that their daily lives were not very interesting and involved few social contacts. Twenty-five percent of them declared that they had financial problems; twelve percent also said they had to face problems of disease-related stigma and embarrassment. CONCLUSIONS: The results suggest that emotional stability is an important psychological determinant of perceived distress among the caregivers of hemodialysed patients. Assessing this personality trait and the reciprocal experience of chronicity in patients and caregivers may help nephrology teams identify subjects at major psychological risk, and to select the appropriate psychological support.