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Addressing the bias problem in the assessment of the quality of life of patients with dementia: Determinants of the accuracy and precision of the proxy ratings

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The journal of nutrition, health & aging

Abstract

Objectives

We aimed to examine the discrepancy between patients and caregivers’ ratings of quality of life in terms of accuracy and precision, and identify factors associated with it, in order to facilitate the use of this scale as dementia progresses.

Design

Cross-sectional analytic study.

Setting

Day care centres. Participants: Community-living patients with Alzheimer’s disease in early or moderate stage and their principal caregivers.

Measurements

Participants rated patients’ quality of life using DEMQOL. The discrepancy was assessed using the individual difference score and the residuals for each domain of DEMQOL. The scores on Mini-Mental State Examination, Geriatric Depression Scale, Neuropsychiatric Inventory, Clinical Insight Rating Scale, Cumulative Illness Rating Scale, Health Utilities Index Mark 3 and Zarit Burden Interview were considered as possible predictors of the discrepancy.

Results

A total of 276 subjects participated in the study (138 patients with Alzheimer’s disease and their caregivers). Discrepancy measured by individual difference score was lower than that measured by the residuals. Burden and mood-related symptoms explained the positive differences and residuals, while pain, self-perceived depression and cognition determined the negative ones.

Conclusions

Differences exist between patients and caregivers’ perceptions about subjective states. The evaluations of each informant seem to be influenced by their own emotional state and the inner experience of the effects of the disease. Caregivers’ ratings on DEMQOL could be useful to monitor the efficacy of any treatment whenever burden is low and patients have no great physical or emotional suffering.

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References

  1. Jacqmin-Gadda H, Alperovitch A, Montlahuc C et al. 20-Year prevalence projections for dementia and impact of preventive policy about risk factors. Eur J Epidemiol 2013;28(6): 493–502.

    Article  PubMed  Google Scholar 

  2. Keating N, Gaudet N. Quality of life of persons with dementia. J Nutr Health Aging 2012;16(5): 454–6.

    Article  CAS  PubMed  Google Scholar 

  3. Logsdon RG, Gibbons LE, McCurry SM et al. Assessing quality of life in older adults with cognitive impairment. Psychosom Med 2002;64(3): 510–9.

    Article  PubMed  Google Scholar 

  4. Smith SC, Lamping DL, Banerjee S, et al. Measurement of health-related quality of life for people with dementia: development of a new instrument (DEMQOL) and an evaluation of current methodology. Health Technolog Assess 2005;9(10): 1–93.

    CAS  Google Scholar 

  5. Bosboom PR, Alfonso H, Eaton J et al. Quality of life in Alzheimer’s disease: different factors associated with complementary ratings by patients and family carers. Int Psychogeriatr 2012;24(5): 708–21.

    Article  PubMed  Google Scholar 

  6. Huang HL, Chang MY, Tang JS, et al. Determinants of the discrepancy in patient- and caregiver-rated quality of life for persons with dementia. J Clin Nurs 2009;18(22): 3107–18

    Article  PubMed  Google Scholar 

  7. Schulz R, Cook TB, Beach SR, et al. Magnitude and Causes of Bias Among Family Caregivers Rating Alzheimer Disease Patients. Am J Geriatr Psychiatry 2012;21(1): 14–25.

    Article  Google Scholar 

  8. Berwig M, Leicht H, Gertz HJ. Critical evaluation of self-rated quality of life in mild cognitive impairment and Alzheimer’s disease—further evidence for the impact of anosognosia and global cognitive impairment. J Nutr Health Aging 2009;13(3): 226–30.

    Article  CAS  PubMed  Google Scholar 

  9. McKhann G, Drachman D, Folstein M, et a. Clinical diagnosis of Alzheimer’s disease: report of the NINCDS-ADRDA Work Group under the auspices of Department of Health and Human Services Task Force on Alzheimer’s Disease. Neurology 1984;34(7): 939–44.

    Article  CAS  PubMed  Google Scholar 

  10. Reisberg B et al.. The Global Deterioration Scale for Assessment of Primary Degenerative Dementia. Am J Psych 1982;139(9): 1136–1139.

    Article  CAS  Google Scholar 

  11. Lucas-Carrasco R, Lamping DL, Banerjee S et al. Validation of the Spanish version of the DEMQOL system. Int Psychogeriatr 2010;22(4): 589–97.

    Article  PubMed  Google Scholar 

  12. Folstein MF, Folstein SE, McHugh PR. ‘Mini-Mental State’: a practical method for grading the cognitive state of patients for the clinician. J Psychiatr Res 1975;12: 189–198.

    Article  CAS  PubMed  Google Scholar 

  13. Haubois G, de Decker L, Annweiler C, et al. Derivation and validation of a Short form of the Mini-Mental State Examination for the screening of dementia in older adults with a memory complaint. Eur J Neurol 2013;20(3): 588–90.

    Article  CAS  PubMed  Google Scholar 

  14. Yesavage JA, Brink TL, Rose TL, et al. Development andvalidation of a geriatric depression screening scale: a preliminary report. J Psychiatric Res 1983;22: 37–49.

    Google Scholar 

  15. Almeida OP, Almeida SA. Short versions of the geriatric depression scale: a study of their validity for the diagnosis of a major depressive episode according to ICD-10 and DSM-IV. Int J Geriatr Psychiatry 1999;14(10): 858–65.

    Article  CAS  PubMed  Google Scholar 

  16. Cummings JL, Mega M, Gray K, et al. The Neuropsychiatric Inventory: comprehensive assessment of psychopathology in dementia. Neurology 1994;44(12): 2308–2314.

    Article  CAS  PubMed  Google Scholar 

  17. Cheng ST, Kwok T, Lam LC. Neuropsychiatric symptom clusters of Alzheimer’s disease in Hong Kong Chinese: prevalence and confirmatory factor analysis of the Neuropsychiatric Inventory. Int Psychogeriatr 2012;24(9): 1465–73.

    Article  PubMed  Google Scholar 

  18. Ott BR, Fogel BS. Measurement of depression in dementia: self vs clinician rating. Int J Geriatr Psychiatry 1992;7: 899–904.

    Article  Google Scholar 

  19. Zarit SH and Zarit JM. The Memory and behavior problem checklist and the burden interview. Technical Report, Pennsilvania State University, 1983.

    Google Scholar 

  20. Feeny D, Furlong W, Boyle M, et al. Multi-attribute health status classification systems: health utilities index. Pharmacoeconomics 1995;7: 490–502.

    Article  CAS  PubMed  Google Scholar 

  21. Ruiz M, Rejas J, Soto J, et al. Adaptation and validation of the Health Utilities Index Mark 3 into Spanish and correction norms for Spanish population. Med Clin 2003;120(3): 89–96.

    Article  Google Scholar 

  22. Miller MD, Paradis CF, Houck PR, et al. Rating chronic medical illness burden in geropsychiatric practice and research: application of the Cumulative Illness Rating Scale. Psychiatry Res 1992;41: 237–248.

    Article  CAS  PubMed  Google Scholar 

  23. Parmelee PA, Thuras PD, Katz IR, et al. Validation of the cumulative illness rating scale in a geriatric residential population. J Am Geriatr Soc 1995;43: 130.

    CAS  PubMed  Google Scholar 

  24. Cronbach LJ and Meehl, PE. Construct validity in psychological tests. Psychol Bull 1955;52: 281–302.

    Article  CAS  PubMed  Google Scholar 

  25. Lin L.I-K. A concordance correlation coefficient to evaluate reproducibility. Biometrics 1989;45: 255–268.

    Article  CAS  PubMed  Google Scholar 

  26. MacKinnon DP. Introduction to statistical mediation analysis. Multivariate Applications Series, 2008.

    Google Scholar 

  27. Linn RL, Slinde JA. The determination of the significance of change between pre- and posttesting periods. Rev Educ Res 1977;47: 121–150.

    Article  Google Scholar 

  28. Boyer F, Novella JL, Morrone I. Agreement between dementia patient report and proxy reports using the Nottingham Health Profile. Int J Geriatr Psychiatry 2004;19(11): 1026–34.

    Article  CAS  PubMed  Google Scholar 

  29. Buckley T, Fauth EB, Morrison A, et al. Predictors of quality of life ratings for persons with dementia simultaneously reported by patients and their caregivers: the Cache County (Utah) Study. Int Psychogeriatr 2012;24(7): 1094–102.

    Article  PubMed Central  PubMed  Google Scholar 

  30. Gitlin LN, Hodgson N, Piersol CV, et al. Correlates of quality of life for individuals with dementia living at home: the role of home environment, caregiver, and patient-related characteristics. Am J Geriatr Psychiatry, 2013. doi: 10.1016/j.jagp.2012.11.005.

    Google Scholar 

  31. Sands LP, Ferreira P, Stewart AL, et al. What explains differences between dementia patients’ and their caregivers’ ratings of patients’ quality of life? Am J Geriatr Psychiatry 2004;12(3): 272–80.

    Article  PubMed  Google Scholar 

  32. Zhao H, Novella JL, Dramé M, et al. Factors associated with caregivers’ underestimation of quality of life in patients with Alzheimer’s disease. Dement Geriatr Cogn Disord 2012;33(1): 11–7.

    Article  CAS  PubMed  Google Scholar 

  33. Rinaldi P, Spazzafumo L, Mastriforti R, et al. Predictors of high level of burden and distress in caregivers of demented patients: results of an Italian multicenter study. Int J Geriatr Psychiatry 2005;20(2): 168–74.

    Article  CAS  PubMed  Google Scholar 

  34. Watson LC, Lewis CL, Moore CG, et al. Perceptions of depression among dementia caregivers: findings from the CATIE-AD trial. Int J Geriatr Psychiatry 2011;26(4): 397–402.

    Article  PubMed  Google Scholar 

  35. Snow AL, Kunik ME, Molinari VA, et al. Accuracy of self-reported depression in persons with dementia. J Am Geriatr Soc 2005;53(3): 389–96.

    Article  PubMed  Google Scholar 

  36. Cipher DJ, Clifford PA. Dementia, pain, depression, behavioral disturbances, and ADLs: toward a comprehensive conceptualization of quality of life in long-term care. Int J Geriatr Psychiatry 2004;19(8): 741–8.

    Article  PubMed  Google Scholar 

  37. Beer C, Flicker L, Horner B et al. Factors associated with self and informant ratings of the quality of life of people with dementia living in care facilities: a cross sectional study. PLoS One 2010;5(12): 15621.

    Article  Google Scholar 

  38. Scherder E, Herr K, Pickering G, et al. Pain in dementia. Pain 2009;145(3): 276–278.

    Article  PubMed  Google Scholar 

  39. Smigorski K, Leszek J. Pain Experience and Expression in Patients with Dementia. In: Smigorski K (ed) Health Management, 2010. InTech, DOI: 10.5772/9886.

    Chapter  Google Scholar 

  40. Conde-Sala JL, Reñé-Ramírez R, Turró-Garriga O et al. Clinical differences in patients with Alzheimer’s disease according to the presence or absence of anosognosia: implications for perceived quality of life. J Alzheimers Dis 2013;33(4): 1105–16.

    CAS  PubMed  Google Scholar 

  41. Hurt CS, Banerjee S, Tunnard C, et al. Insight, cognition and quality of life in Alzheimer’s disease. J Neurol Neurosurg Psychiatry 2010;81(3): 331–6.

    Article  CAS  PubMed  Google Scholar 

  42. Ready RE, Ott BR, Grace J. Insight and cognitive impairment: effects on quality-of-life reports from mild cognitive impairment and Alzheimer’s disease patients. Am J Alzheimers Dis Other Demen 2006;21(4): 242–8.

    Article  PubMed  Google Scholar 

  43. Clare L; Nelis SM., Martyr A, et al. The influence of psychological, social and contextual factors on the expression and measurement of awareness in early-stage dementia: testing a biopsychosocial model. Int J Geriatr Psychiatry 2012;27(2): 167–77.

    Article  PubMed  Google Scholar 

  44. Gómez-Gallego M, Gómez-Amor J, Gómez-García J. Determinants of quality of life in Alzheimer’s disease: perspective of patients, informal caregivers, and professional caregivers. Int Psychogeriatr 2012;24: 1805–1815.

    Article  PubMed  Google Scholar 

  45. Naglie G, Hogan DB, Krahn M, et al. Predictors of patient self-ratings of quality of life in Alzheimer disease: cross-sectional results from the Canadian Alzheimer’s Disease Quality of Life Study. Am J Geriatr Psychiatry 2011;19: 891–890.

    Article  PubMed Central  PubMed  Google Scholar 

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Correspondence to Maria Gomez-Gallego.

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Gomez-Gallego, M., Gomez-Garcia, J. & Ato-Lozano, E. Addressing the bias problem in the assessment of the quality of life of patients with dementia: Determinants of the accuracy and precision of the proxy ratings. J Nutr Health Aging 19, 365–372 (2015). https://doi.org/10.1007/s12603-014-0564-7

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  • DOI: https://doi.org/10.1007/s12603-014-0564-7

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