Parkinson's Disease, Cognitive Status and Caregiver Outcomes.

Cognitive impairment in Parkinson’s disease (PD) can impact negatively on caregivers and is associated with carer distress and feelings of burden. To investigate this relationship we examined level of burden, coping strategies, depression, anxiety and potential positive aspects of caregiving in the caregivers of 104 PD patients. The PD patients were classified as either showing normal cognition (PD-N; n=57), with mild cognitive impairment (PD-MCI; n=31) or with dementia (PD-D; n=16). The key finding was that mean Zarit burden score increased between carers of PD-N (M=14.1, SD=12.0) through to PD-MCI (M=21.1, SD=9.86) and PD-D (M=27.8, SD=10.61); F (2,101) =9.96, p<0.001. Post hoc tests (Newman-Keuls) identified significantly higher Zarit burden scores in PD-D caregivers compared to both PD-N (p<.001) and PD-MCI patients (p<.05), but carers of PD-MCI patients also showed increased burden scores relative to those of PD-N patients (p<.05). The proportion of carers showing significant levels of burden (Zarit burden score ≥21) also increased as cognition declined (21% for PD-N; 58% for PD-MCI; and 81% for PD-D). Time spent providing care and problem-focused, emotion-focused and dysfunctional coping strategies also increased with worsening cognition. While caregiver use of problem-focused coping mediated the association between patient cognitive status and caregiver burden, we could not be confident about this relationship as the inverse model was also significant. Caregiver Zarit burden was independent of caregiver depression, anxiety and positive attributions of caregiving. The study highlights the impact of Parkinson’s disease on those providing care when the patients’ cognition is poor, including those with MCI. Caregiver well-being has important implications for nursing home placement and disease course