Determinants of Frailty Among of Informal Caregivers of Demented Patient

Frailty, a transitional state between successful and pathological aging, may be benefit from early multi-interventional intervention.

Fried's criteria are the more commonly used criteria to diagnose frailty :

• Loss of weight > 4.5 kg over one year,
• Self-reported exhaustion,
• Low muscle strength (handgrip <20% norm for age and sex),
• Low physical activity
• Low gait speed (<0.8m/s). According to the number of Fried's criteria, subjects are considered frail (≥ 3 Fried's criteria), pre-frail (1-2 Fried's criteria) or robust (0 Fried's criterion).

A large proportion of care is believed to be delivered by informal caregivers (e.g., spouses, next of kin). The caregivers' burden experienced as "enduring stress and frustration" due to caregiving, affects caregivers' mental health with depression, anxiety and sleep disorders, increases caregivers' morbidity and mortality. Multi-interventional studies (including physical and psychological wellbeing) have proven their accuracy to improve quality of life of caregivers.

In France, caregivers (>60 years) of demented people number have been estimate to 3.3 million (DREES).

For more than one year, in the Broca memory center (3000 patients/ years), caregivers can benefit from a comprehensive medico-psychosocial assessment during a day care hospital. Frailty is assessed in usual care. Two caregivers a week benefit from this assessment. The same day care hospital has been implemented in the "Paul Brousse" hospital (100 patients/year) : One caregiver a week benefit from this assessment.

Main objective:

To assess the relationship between frailty among informal caregivers of demented patients and the caregiver's burden (Zarit scale).

Secondary objective:

To assess determinants of frailty among caregivers.

Main outcome :

Caregiver burden will be determined according to the Zarit scale. The Zarit scale is an auto-questionnaire which includes 22 questions (rated from 0 to 4 points) and scores out of 88. A higher score reflects a higher caregiver burden.

Frailty will be defined by Fried criteria. Subjects will be considered as frail (≥ 3 Fried's criteria), pre-frail (1-2 Fried's criteria) or robust (0 Fried's criteria).

Secondary outcomes

• Age, sex, educational level
• Treatments et polypharmacy (≥ 4 treatments)
• Neuropsychological test if cognitive complaint : caregivers will be categorized as cognitively normal, mild cognitive impairment or dementia.
• Depression according to the Pichot scale and the Geriatric Depression Scale.
• Anxiety according to the Goldberg scale
• Nutritional Assessment: mini nutritional assessment and body mass index.

Feasibility :

Eighty caregivers will be included in the Broca hospital and 40 in the Paul Brousse hospital. To reach the calculated number of subjects to include (n=120), inclusions will take place during 1 year and a half.

Statistical analysis

Main objective :

To disclose a difference in the Zarit score of 11 points (retrospective analysis of collected data) with 80% power and α 5% risk, 120 subjects have to be included. The population will be described and factors associated with the Zarit scale in uni-variate analysis will be studied in a multiple linear regression model.

Analysis will be also performed according to 3 groups: frail, pre-frail and robust.