Across the Cognitive Impairment Continuum Increasing Patient Dependence is Associated with an Increase in Caregiver Burden Loretto Lacey Janssen Alzheimer s Immunotherapy Dublin, Ireland Alzheimer's Europe Meeting Warsaw, Poland October 2011
Collaborators Jacqui Buchanan (Janssen Alzheimer s Immunotherapy) Chris Leibman (Janssen Alzheimer s Immunotherapy) Jonathan de Courcy (Adelphi Real World, UK) Daniel Shaw (Adelphi Real World, UK) Eddie Jones (Adelphi Real World, UK) 2
Background Alzheimer s disease (AD) in its early stages is often diagnosed as mild cognitive impairment (MCI) or predementia Alzheimer s As cognitive impairment progresses individuals become increasingly dependent on caregivers to help them with day to day living The Dependence Scale (DS) was developed to directly measure the actual level of care required by a patient with Alzheimer s disease (AD) because of impairments in cognition, function, and behaviour a a Stern Y et al. Assessing patient dependence in Alzheimers disease. J Gerontol Med Sci. 1994;49:M216-M222. 3
Aim To examine the association between patient dependence as measured with the Dependence Scale (DS) and caregiver measures of subjective burden (measured with the Zarit burden interview, ZBI) across the cognitive impairment continuum 4
Methods: Sample Adelphi Dementia-specific Programme (DSP)# Survey of physicians (N=443), patients (N=383), and nonprofessional caregivers (N=383) EU countries involved: France, Germany, Spain, UK Survey conducted August October 2010 MCI patients were defined by a diagnosis of MCI or pre-dementia AD made by the physician AD stages were defined by an AD diagnosis and mild MMSE>19, moderate MMSE10-19 or severe MMSE<10 For each patient record caregivers were asked to complete a caregiver questionnaire # Anderson P et al 2008. Real-world physician and patient behaviour across countries: disease specific programmes-a means to understand Curr Med Res Opin 24:3063-3072 5
Methods: Analyses Correlations between dependence (DS) and caregiver burden (ZBI) were performed. Mean comparison between patients groups was done using one-way ANOVA with bonferroni correction for multiple comparison. A stepwise ordinary least squares (OLS) model was created to identify significant drivers of ZBI using various patient and caregiver demographics and characteristics. 6
Key Measures Included in Survey Patient and caregiver demographics Caregiver s relationship to patient Patient s cognitive status and causes (including AD) Patient s functional status Patient s most recent Mini-Mental State Examination(MMSE) score Patient s behavioural status Patient s co-morbid conditions Dependence Scale (DS) Resource use Zarit Caregiver Burden Interview Caregiver health status/utility (EQ-5D) 7
Sample Demographics Patient age, yrs (mean ± SD) France (N = 97) Germany (N = 21) Spain (N = 170) UK (N = 95) Total (N = 383) 77.9 ± 7.1 74.0 ± 5.2 77.2 ± 8.4 78.0 ± 7.3 77.4 ± 7.7 Female 57.7% 42.9% 60.6% 55.8% 57.7% Caregiver age, yrs (mean ± SD) 65.2 ± 13.9 63.5 ± 12.4 51.7 ± 13.4 63.9 ± 15.2 63.2 ± 14.0 Relationship to patient Partner/ spouse 54.7% 61.9% 44.1% 57.5% 51.1% Child 29.5% 28.6% 39.3% 20.2% 31.5% Other 15.8% 9.5% 16.7% 22.3% 17.5% 11
Severity of the Cohort MCI (N = 48) Mild AD (N = 121) Moderate AD (N = 161) Severe AD (N = 53) Total (N = 383) MMSE (mean ± SD) 23.3 ± 3.1 *(n=28) 22.5± 2.1 *(n=95) 15.5± 2.7 *(n=122) 6.38± 2.5 *(n=24) 18.0± 5.6 *(n=266) *not all patients have a current MMSE score 12
Dependence Scale (Range 0-15) Increasing patient severity is correlated with an increase in Dependence, as measured on the Dependence Scale Analyses of differences between groups were performed using one-way analysis of variance with Bonferroni corrections for multiple comparisons. Patient s severity group P values: MCI vs. Mild : p = 1.000 Mild vs. Moderate : p = <0.001 MCI vs. Moderate : p = <0.001 Mild vs. Severe : p = <0.001 MCI vs. Severe : p = <0.001 Moderate vs. Severe : p = <0.001
Zarit Caregiver Burden Index Increasing patient severity is correlated with an increase in caregiver burden, as measured on the Zarit Burden Index Analyses of differences between groups were performed using one-way analysis of variance with Bonferroni corrections for multiple comparisons. Patient s severity group P values: MCI vs. Mild : p = 1.000 Mild vs. Moderate : p = <0.001 MCI vs. Moderate : p = <0.001 Mild vs. Severe : p = 0.003 MCI vs. Severe : p = <0.001 Moderate vs. Severe : p = 1.000 Note: The Zarit Score runs from 0 88 where 88 would equal the highest level of burden
Relationship between Burden and Dependence Zarit Burden Score 10 20 30 40 50 Mean Zarit Burden Score for each level of Dependence (Pearson s 0.3362, p<0.0001) 0 5 10 15 Dependence Scale
Caregiver Zarit Burden Score Stage of cognitive impairment Intercept Age of patient Gender of patient Age of caregiver DS sum Doctors Opinion MMSE score Number of behavioural problems Number of ADL/IADL Limitations 29.880 NS NS NS 1.61 NS -0.519 NS NS P <0.001 P <0.001 0.008 OLS model Calculated using stepwise backward elimination; starting with all of the above components, then removing the components that were not statistically significant predictors of Zarit Burden score. Zarit = intercept + age of patient + gender of patient + age of caregiver + DS sum + MMSE score + Doctors Opinion + number of behavioral problems + number of ADL/IADL limitations. R 2 = 0.17; P <0.001. NS = not significant. 16
Limitations Small sample size in some countries; therefore, country effect could not be evaluated thoroughly There may be other factors, not captured in model that influence caregiver burden (e.g., psychological resources and social resources a ) a Vitaliano PP et al. A model of burden in caregivers of DAT patients. In: Light E, Lebowitz B, eds. Alzheimer s Disease Treatment and Family Stress: Future Directions for Research. Washington, DC: GPO; 1989:267-291. 17
Conclusions A significant relationship exists between patient dependence and the burden that this puts on their caregiver These results suggest that as patients progress across the continuum of cognitive impairment, patient dependence increases and the burden to the caregiver increases A significant increase in caregiver burden occurs when a patient progresses from mild to moderate AD dementia 18
Back-up slides 19
DSP Methodology Collects Insights From Both the Physician s and Patient s Perspectives PHYSICIANS Primary Care & Specialists PATIENTS Consulting Physician completed Patient completed DOCTOR S PERSPECTIVE Patient data Patient record forms (PRF) completed by doctors prospectively Matched with PRF Matched sample CAREGIVER S PERSPECTIVE Caregiver data Self-completion (CSC) questionnaires completed by caregivers CSC 20