Awareness of Deficit in Alzheimer's Disease: Relation to Caregiver Burden 1

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1 Copyright 1997 by The Cerontological Society of America The Cerontologist Vol.37, No. 1,20-24 Patients with Alzheimer's disease (AD) show varying degrees of awareness of their deficits. To examine the impact of this phenomenon upon the distress experienced by family caregivers of AD patients, we analyzed caregiver burden in relation to patient awareness of deficit in three different functional domains. The relationship of burden to selected sociodemographic variables was also explored. Results of multiple regression analyses suggested that caregiver burden was associated with impaired patient awareness of memory deficit independent of disease stage and dementia severity. The findings suggest that impaired awareness may be an important mediator of caregiver burden, a concern in the management of AD. Key Words: Dementia, Anosognosia, Insight Awareness of Deficit in Alzheimer's Disease: Relation to Caregiver Burden 1 Benjamin Seltzer, MD, 23 Jennifer J. Vasterling, PhD 23 JoAnne Yoder, MSW, 2 and Kenneth A. Thompson, BS 3 Anosognosia, or unawareness of deficit, is a well recognized symptom of brain injury (Prigatano & Schacter, 1991). Perhaps the best known example is unawareness of weakness on the left side of the body displayed by some individuals following right hemisphere strokes. Anosognosia also occurs in patients with widespread cerebral disease, including the degenerative dementias. Patients with Alzheimer's disease (AD) are frequently observed to be unaware that their memory and other intellectual functions are significantly impaired (McGlynn & Kaszniak, 1991; Sevush & Leve, 1993). Anosognosia in AD has been studied in relation to disease variables such as duration of dementia, disease stage, and neuropsychological test scores (Feher, Larrabee, Sudilovsky, & Crook, 1994; Feher, Mahurin, Inbody, Crook, & Pirozzolo, 1991; Mangone et al., 1991; Reed, Jagust, & Coulter, 1993; Seltzer, Vasterling, & Boswell, 1995a; Vasterling, Seltzer, Foss, & Vanderbrook, 1995); disturbances of mood and other psychiatric symptoms (DeBettignies, Mahurin, & Pirozzolo, 1990; Feher et al., 1991; Feher et al., 1994; Kaszniak, DiTraglia, & Trosset, 1993; Mangone et al., 1991; Reed et al., 1993; Seltzer et al., 1995a; Seltzer, Vasterling, Hale, & Khurana, 1995b; Sevush & Leve, 1993); and biological markers such as cerebral blood flow (Reed et al., 1993; Starkstein et al., 1995). Unawareness of deficit in AD is of interest for several reasons. First, the study of this 1 This research was presented at the 48th Annual Scientific Meeting of the Cerontological Society of America, Los Angeles, California, November Division of Behavioral and Geriatric Neuropsychiatry, Department of Psychiatry and Neurology, Tulane University School of Medicine. Address correspondence to Benjamin Seltzer, MD, Department of Psychiatry and Neurology, Tulane University Medical Center, 1430 Tulane Avenue, New Orleans, LA 'Department of Veterans Affairs Medical Center, New Orleans, LA. phenomenon affords an opportunity to examine the neural basis for conscious awareness. It may also contribute to an understanding of the biology of AD. Finally, unawareness of deficit impacts directly on the well-being of individuals with AD and their caregivers. Patients who are unaware of memory and other intellectual deficits may engage in activities that might cause physical or financial harm to themselves and others. Lack of awareness may interfere with their consenting to potential therapies. This particular symptom may also contribute to the distress frequently experienced by caregivers of AD patients (DeBettignies et al., 1990). Unawareness of deficit in AD is not a unitary phenomonenon. Patients show different degrees of unawareness depending upon the domain of function, e.g., memory and ability to perform activities of daily living (ADLs; Green, Goldstein, Sirockman, & Green, 1993; Vasterling et al., 1995). De Bettignies et al. (1990) examined the relationship of caregiver burden to unawareness of impaired independent living skills alone and found that greater unawareness was associated with higher levels of caregiver distress. Whether diminished patient insight into other domains of function affected by the disease also contributes to caregiver burden remains unknown. As part of our comprehensive assessment of anosognosia in AD patients, we measured awareness of deficit in multiple functional domains by calculating the discrepancy between patients' self-assessments and those of their caregivers on scales rating different functions affected by AD. To investigate the practical implications of disturbed awareness in terms of caregiver burden, we examined discrepancy scores in three domains of function, i.e., memory, self-care, and social function, in relation to caregiver distress using the Burden Interview of Zarit, Reever, and Bach-Petersen (1980). We hypothesized that the less 20 The Gerontologist

2 patients were aware of their deficits, the more distress their caregivers would experience, regardless of the severity of the dementia. Further, we predicted that, because of its implications for disturbed behavior and interpersonal relations, unawareness in the domain of social functioning would be the most important contributor to caregiver burden. Finally, because caregivers' subjective sense of distress can also be influenced by social variables (Hale & Seltzer, 1995), we examined, in the same group of subjects, the association between caregiver burden and selected sociodemographic factors in order to contrast the contribution of the social support system to that of patient anosognosia in the mediation of caregiver burden. Methods Subjects The subjects were 21 women and 19 men, outpatients at the Alzheimer's Disease and Memory Disorders Clinics at Tulane University Medical Center and the New Orleans V.A. Medical Center. All were assigned the clinical diagnosis of AD according to DSM-IV (American Psychiatric Association, 1994) criteria and "probable AD" according to NINCDS- ADRDA (McKhann et al., 1984) criteria. Only patients judged to be capable of responding to study questionnaires were included. Patients had a mean educational level of 12.1 years (SD, 3.0; range, 6-18) and varied in age from 52 to 87 years (M, 73A years; SD, 7.0) at the time of the assessment. Average estimated age at onset of dementia was 69.7 years (SD, 7.1; range, 51-83), with a mean estimated duration of dementia of 3.5 years (SD, 1.6; range, 1-8). Mean Mini-Mental State Examination (MMSE; Folstein, Folstein, & McHugh, 1975) score was 18.5 (SD, 5.0; range, 7-27). Twenty-three patients had a Clinical Dementia Rating (CDR; Hughes, Berg, Danziger, Coben, & Martin, 1982) score of 1 ("mild") and the remaining 17 had a score of 2 ("moderate"). For each patient, a caregiver responded to the same questionnaires administered to the patient. These comprised 27 women and 13 men, of whom 23 were spouses, 11 were adult children, and 6 were other family members. As described in detail previously (Seltzer et al., 1995b; Vasterling et al., 1995), unawareness of, or lack of insight into, deficits was expressed as the "discrepancy score" between a patient's rating and that of his or her caregiver on an instrument tapping a specific domain of function often affected by AD. Memory function was assessed using the Everyday Memory Questionnaire (EMQ) of Sunderland, Harris, and Baddeley (1983). This instrument probes 35 memory problems (e.g., forgetting to keep appointments; repeating oneself) commonly experienced by AD patients. For each item there is a fivepoint rating, anchored at "never" (0 points) and "several times in one day" or "on every occasion" (4 points). Thus, total scores potentially range from The domains of social awareness and ability to perform ADLs ("self-care") were assessed using the Patient Competency Rating Scale (PCRS) of Prigatano et al. (1986). This is a 30-item questionnaire designed to tap everyday functions in patients with cerebral disease. For each item, the respondent is asked to rate how easy or difficult a particular activity is for the patient to perform, using a scale encompassing five points: "can do with ease" (scored as 0 points), "fairly easy to do" (1 point), "can do with some difficulty" (2 points), "very difficult to do" (3 points), and "can't do" (4 points). If the activity (e.g., doing the laundry) does not apply to a particular individual, the respondent is instructed to answer the item as if it were something the patient "had to do." For the purpose of this study, by the unanimous consensus of three independent raters (B.S., J.V., and K.T.), 14 items were grouped together as a measure of social awareness (PCRS Social subscale) and 6 as a measure of ADLs (PCRS Self-care subscale; Table 1). Thus, social awareness scores potentially range from 0-56 and self-care awareness scores potentially range from The PCRS has previously been demonstrated to be sensitive to disease of the frontal lobes (Crattan, Eslinger, Mattson, Rigamonti, & Price, 1994). For all three instruments, the versions administered differed only in the wording used to reflect the perspectives of patients and caregivers. Questionnaires were administered independently to patients and their caregivers and were read to the patients. Sample means and standard deviations for the three awareness discrepancy scores are listed in Table 2. Caregiver burden was measured by administering to each caregiver the Burden Interview of Zarit et al. (1980), a 22-item instrument, with a potential range of scores from 0-88, which has been widely used in AD caregiver research. Also collected were two pieces of Table 1. Patient Competency Rating Scale (PCRS) (Prigatano etal., 1986) Social Subscale Starting a conversation in a group Getting help when confused Adjusting to unexpected changes Handling arguments with people one knows well Accepting criticism from others Controlling crying Acting appropriately when around friends Showing affection to people Participating in group activities Recognizing something one said or did is upsetting to others Controlling temper when upset Keeping oneself from being depressed Keeping emotions from interfering with everyday activities Controlling laughter Self-care Subscale Preparing meals Dressing oneself Taking care of personal hygiene Washing the dishes Doing the laundry Taking care of finances Vol. 37, No. 1,

3 Variable Table 2. Means, Standard Deviations, and Frequencies of Burden Interview Scores, Awareness Discrepancy Scores, and Social Variables Burden interview Memory discrepancy Self-care discrepancy Social discrepancy % Caregivers living with patient Outside assistance % none % occasional % hours/week % ss40 hours/week Mean (%) SD sociodemographic data that might contribute to caregiver burden: whether or not the caregiver actually resided with the patient and the amount of outside assistance provided to caregivers. The former was recorded as a dichotomous variable; the latter, a 4-point scale with 0 points = no assistance, 1 = occasional assistance, 2 = 20 to 39 hours of assistance per week, and 3 = 40 or more hours of assistance per week. We have previously shown that these two variables mediate the distress experienced by caregivers of AD patients in this population (Hale & Seltzer, 1995). Summary statistics for Burden Interview scores and sociodemographic data are presented in Table 2. Two competing statistical models, making use of step-wise multiple regression equations, were constructed to evaluate factors contributing to caregiver burden. One explored sociodemographic variables and the other dealt with anosognosia. Results To explore the relationship of caregiver burden to social support factors, we first conducted a step-wise multiple regression analysis in which Zarit Caregiver Burden scores served as the dependent variable and the two sociodemographic measures (whether or not the caregiver resided with the patient and amount of weekly outside assistance provided to caregivers) were entered as the independent variables. P to enter was set at.05. Neither of the variables were entered into the equation, however, suggesting that, in this particular sample, they were not related to caregiver burden. Next, to examine the extent to which impaired patient awareness in three domains of function (i.e., memory, social awareness, and self-care) were associated with caregiver burden, another step-wise multiple regression analysis was performed. For this equation, Burden Interview scores served as the dependent variable; EMQ, PCRS Social subscale, and PCRS Self-care subscale discrepancy scores were entered as independent variables; and p to enter was set at.05. The only variable entered into the equation was EMQ discrepancy scores. The two remaining variables were not added to the equation, reaching significance levels of p >.26. The final equation, identical to the simple correlation of EMQ discrepancy scores with Zarit Caregiver Burden scores (r =.39), was significant [F("1,37) = 6.78, p <.02] and accounted for approximately 15% of the variance in caregiver burden. Because previous research has demonstrated associations between impaired awareness of memory deficit, disease stage, and dementia severity (see for example Seltzer et al., 1995a; Sevush & Leve, 1993; Vasterling et al., 1995), a subsequent stepwise multiple regression equation was created to control for shared variance among measures of these variables. Burden scores again served as the dependent variable; duration of dementia and EMQ discrepancy, CDR, and MMSE scores were entered as the independent variables; and p to enter was set at.05. The only variable entered into this equation was again EMQ discrepancy scores. Thus, the equation was identical to that described above, with EMQ scores accounting for approximately 15% of the variance in caregiver burden. None of the remaining variables were added to the equation because they reached significance levels of p >.28. A correlation matrix was created to describe the interrelatedness of all variables considered in the three regression analyses. The results are displayed in Table 3. Discussion In this sample of AD family caregivers, subjective distress related to caregiving, as measured by the Burden Interview of Zarit et al. (1980), correlated positively with patient unawareness of memory deficit, measured as EMQ discrepancy scores. As patient underestimation of memory deficit increased, caregiver burden increased. No such relationship was found between caregiver burden and patient unawareness of impaired ability to perform activities of daily living and inappropriate social functioning. The sociodemographic variables also failed to correlate with caregiver burden, suggesting that the distress experienced by this sample of caregivers was not a result of two important social factors that have previously been shown to contribute to caregiver burden, i.e., living with the patient, having outside assistance. It is conceivable that certain disease variables, such as duration of illness and severity and stage of dementia, might contribute to caregiver burden. If this were true, anosognosia for memory deficit might correlate with caregiver burden simply because patients with impaired awareness tend to have dementia of longer duration and greater severity than those whose insight is not disturbed. The third statistical operation (see above), however, controlled for these factors and failed to show a significant association between caregiver distress and length of illness and objective measures of dementia severity, such as CDR rating and MMSE scores, but did demonstrate a significant correlation with anosognosia for memory deficit, even after shared variance with duration of 22 The Gerontologist

4 Table 3. Correlations Among Caregiver Burden Scores, Awareness Discrepancy Scores, and Selected Social Disease Variables Variable Bl Self- Memory care Social Discrep. Discrep. Discrep. Lives with Amount Patient Assist. CDR MMSE Duration Dementia Bl Memory discrepancy Self-care discrepancy Social discrepancy Lives with patient Amount assist. CDR MMSE Duration dementia 0.39*** * *** 0.47** *** 0.75* * -0.52* *** -0.43** *** * Notes: Bl = Burden Interview (Zarit et al., 1980); CDR = Clinical Dementia Rating (Hughes et al., 1982); MMSE = Mini-mental State Examination (Folstein et al., 1975); amount assist. = amount of assistance (see text); discrep. = discrepancy scores (see text); all correlations are two-tailed. *p <.001; **p <.01; ***p <.05. dementia, dementia severity, and disease stage was controlled. The findings therefore support our prediction of an association between caregiver burden and unawareness of deficit in at least one salient feature of AD memory deficit. In this particular sample, at least, unawareness of deficit is more important than selected social support variables as a contributor to caregiver distress. Furthermore, the failure to find a significant association with duration of illness and certain objective measures of dementia severity suggests that it is the unawareness of the memory deficit, rather than disease stage or dementia severity, that contributes to the distress experienced by caregivers. We were unable to demonstrate a significant relationship between caregiver burden and patient unawareness in the domain of self-care as reported by DeBettignies et al. (1990), who used the same patient-caregiver discrepancy score method but a different instrument to measure awareness of ability to perform ADLs. Also surprising was the lack of significant findings for the domain of impaired social awareness, which we had predicted to be the most important of the three unawareness measures as a determinate of caregiver burden. It is possible, however, that our failure to find positive correlations in two of the three domains was due to different psychometric properties of the instruments used to measure awareness. The EMQ has a greater number of items than the PCRS Social and Self-care subscales, and social skills are probably inherently more difficult to measure than everyday memory. Another possibility is that this sample of patients with predominantly mild to moderate dementia had relative preservation of their social skills and self-care abilities. Studies employing other instruments in a more diverse clinical population might demonstrate associations between caregiver burden and unawareness of deficits in these domains. Also surprising was the lack of significant associations between caregiver distress and the sociodemographic variables. Only two potential factors were assessed, however, and additional measures of formal and informal social support systems might show significant negative correlations with caregiver distress. In recent years it has become apparent that unawareness of memory deficit, a form of "metamemory," is a distinct psychological operation, dissociable from the primary memory deficit in amnestic and dementing illnesses (McClynn & Schacter, 1989). Aside from its relevance to the study of cognitive functions, anosognosia for memory impairment has implications for practical issues such as legal competence, rehabilitation potential, and treatment options in AD and related disorders. As shown in this study, unawareness is also a significant mediator of caregiver burden, a major concern in the treatment and management of AD patients. References American Psychiatric Association. (1994). Diagnostic and Statistical Manual of Mental Disorders, 4th ed. Washington, DC: American Psychiatric Association. 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