Comparing Dementia Diagnostic Methods Used with People with Intellectual Disabilities

Abstract

Accurate detection of dementia in adults with intellectual disabilities is important for clinical care, program planning, and clinical research. This paper reports on a study that examined two major diagnostic methods that varied in the following ways: (1) the extent to which they relied on clinical judgment; (2) the statistical method used to detect declines; and (3) the sensitivity to declines in functioning. Two methods based on testing were compared with one based on clinical judgment. Data were drawn from annual sequential assessments of 168 adults with intellectual disabilities (78 with Down syndrome and 90 with other etiologies). Agreement between testing and clinical judgment methods was 72-75% depending on testing method used. Clinical judgment produced a higher rate of dementia diagnosis for adults with Down syndrome compared with testing methods, suggesting a possible bias. The authors found that diagnostic criteria were useful both for identifying dementia and for describing its characteristics. Our results suggest that clinical judgment could result in a higher number of adults with Down syndrome diagnosed with dementia than methods based on test batteries. Common results across research studies indicate that combinations of sources of information (interviews/direct testing) would be most useful for dementia diagnosis. Future collaboration across research sites is needed to promote rapid progress in this important area, with emphasis on differential diagnosis.

Síndrome de Down y enfermedad de Alzheimer: factores de riesgo, evaluación e intervención

“…En personas con DI severa y profunda, que normalmente quedan fuera del rango de puntuaciones en la mayoría de las pruebas, la evaluación de las habilidades cognitivas y conductuales puede resultar imposible, siendo necesaria la utilización de otros aspectos de la historia y presentación de la persona, tales como el desarrollo de los síntomas neurológicos (Hanney et al, 2009). Muchos investigadores utilizan el diagnóstico basado en el juicio clínico como el "estándar de oro", lo que da como resultado más diagnósticos positivos en adultos con SD que a través de instrumentos de evaluación (Burt et al, 2005).…”

“…Tanto es así que no existe consenso entre los autores acerca de los criterios diagnósticos (Benejam, 2009;Burt et al, 2005;Strydom et al, 2007) y se observa que el DSM parece ser más inclusivo que la CIE-10, pero que ésta enfatiza más la importancia del funcionamiento emocional/motivacional diario (Strydom et al, 2007). Por otro lado, los criterios del DC-LD ("Diagnostic Criteria for Psychiatric Disorders for Use with Adults with Learning Disabilities/Mental Retardation", Royal College of Psychiatrists, 2001) son considerados un subgrupo de los criterios del DSM-IV.…”

Diagnosing Dementia in Adults with Down’s Syndrome

“…The clinical assessment and diagnosis of dementia in adults with DS continues to be fraught with a high risk of inaccurate or even misdiagnosis [17]. Inadequate assessments, intravariability of patients, unreliable care-giver information, poor professional understanding of dementia and the use of different diagnostic criteria can all lead to the failure to detect early memory and cognitive changes.…”

Ageing and mental health problems in people with intellectual disability

“…In a comprehensive review of test batteries, Burt et al [15] compared clinical assessment with test batteries in the assessment of dementia in adults with intellectual disability. Different methods of documenting functional decline result in differences in dementia caseness.…”

“…Clinicians diagnosed more cases of dementia than were diagnosed based on test batteries. Burt et al [15] also make the case for use of multiple tests to improve the sensitivity of dementia diagnosis.…”