BackgroundProfound intellectual multiple disabilities or polyhandicap (PLH) is defined as a combination of profound mental retardation and serious motor deficits resulting in extreme dependence. Support for these patients is multidisciplinary, complex, and time-consuming. Thus, institutional health care workers (HCWs) face specific working conditions: frequent physical tasks, distressed families, and restricted feedback.ObjectivesWe aimed to identify determinants of quality of life (QoL) of HCWs and to study longitudinal evolution.MethodsThe study used data from the French cohort EVAL-PLH. The participants were institutional HCWs of persons with PLH (age ≥ 3 years at the time of inclusion; age at onset of cerebral lesion <3 years old). Two populations were used: (1) cross sectional study: the sample 1 includes the HCWs assessed at T2 (2020–2021); (2) longitudinal study: the sample 2 includes the HCWs assessed at both T1 (2015–2016) and T2 (2020–2021). The data collected included: sociodemographics, health status, professional variables, and psycho-comportemental aspects. QoL was assessed using WHOQOL-BREF which provides 4 scores.ResultsIn comparison with French norms, the physical and social scores of QoL were significantly lower while the psychological score was significantly higher for (i) the 223 HCWs (participation rate 62%) assessed at T2 and (ii) the 61 HCWs assessed at T1 and T2. The main factors modulating QoL were age, marital status, self-perceived financial difficulties, personal chronic disease, anxiety-mood disorders, nature of coping strategies, and burnout.ConclusionThis study confirms the mixed (negative and positive) impact of caring persons with PLH on the institutional HCWs’ QOL. Main determinants of the HCW’s QOL were: older age, single status, perceived financial difficulties, altered health status, burn out and coping strategies.Clinical trial registration number: NCT02400528.