Relationship Between Comorbidities in Patients With Cognitive Complaint and Caregiver Burden: A Cross-Sectional Study

Informal caregivers of patients with a cognitive impairment may face exhaustion while taking care of their relatives, and are themselves at higher risk of disease. The objective was to assess the relationship between patients' comorbidities evaluated with the Charlson index, and the caregiver burden, independently of health disorders related to cognitive impairment.

Cross-sectional observational study.

Memory clinic at the University Hospital of Lyon.

Outpatients with cognitive complaint and consulting a Clinical and Research Memory Centre of Lyon (n = 1300).

Comorbidity was measured using the Charlson Comorbidity Index related to age (CCI). The caregiver burden was measured with the short version of the Zarit Burden Interview (ZBI). The relationship was assessed between the CCI and the mini-Zarit and other patients' characteristics: behavior, cognition, autonomy as assessed respectively by the Neuropsychiatric Inventory (NPI), Mini Mental State Examination (MMSE), Instrumental Activities of Daily Living (IADL), etiology, and stage of the cognitive impairment.

The study included 1300 outpatients: mean age: 80.8 ± 7 years. The mean CCI was 4.8 ± 1.7. The mini-Zarit score: 3.1 ± 2.0. The caregiver burden increased by 0.22 per unit of CCI (95% confidence interval 0.15-0.28, P < .001) in unadjusted analysis. The caregiver burden remained significantly associated with CCI, after adjustment for the MMSE, IADL, and NPI.

The caregiver burden is higher when patients' comorbidities increase, independently of behavioral and psychological symptoms, level of functional autonomy, and the stage of the cognitive disease. However, dementia may be the comorbidity that contributes the most to caregiver burden.