Factors associated with health-related quality of life and burden on relatives of older people with multi-morbidity: a dyadic data study.

Background: This study aimed to identify factors associated with health-related quality of life (HRQoL) and the burden on the relatives of older people with multi-morbidity.

Methods: A secondary analysis of baseline data from 296 dyads, including older patients with multimorbidity and their relatives, which were previously collected in a randomized study. The analysis was conducted to select correlated independent variables to enter a final linear regression analysis of two models with different endpoints: the relatives' HRQoL (EQ5D index) and burden (COPE index: Negative impact scale).

Results: Sixteen variables correlated with the relatives' HRQoL, and 15 with the relatives' burden. Both the HRQoL and burden correlated with both patient and relative variables. A high HRQoL was associated with relatives' working/studying. A high burden was associated with caring for an older person with changed behaviour. A low burden was associated with the relatives' high scores on positive values of caring, quality of support and HRQoL.

Conclusion: Older persons and their relatives should be considered as a unit in the development of support of older people in order to increase the health and quality of life of both groups. To support and protect relatives from a high burden, potential measures could include improving the relative's HRQoL and strengthening their ability to find positive values in care and strengthening reliable and good support from others. The relatives' HRQoL explained the variation in the burden. However, the burden did not explain the variation in the HRQoL, which suggests that the relatives' HRQoL is not so readily affected by their burden, whereas the relatives' HRQoL can influence their burden. The variables used in the regression analyses where chosen to reflect important aspects of the relatives' and older persons' situations. The final models explained 38% of the variation in the relatives' burden but only 10% of the variation in their HRQoL. This could be important to consider when choosing outcome assessments in future studies.