Diagnosing dementia with Lewy bodies (DLB) is challenging both for specialists and primary care physicians. A new composite risk score may aid in differentiating DLB from other forms of dementia.
The Lewy Body Composite Risk Score was recently published in a scientific update paper on DLB by Dr. James E. Galvin, of New York University Langone Medical Center. Previous research of autopsy-confirmed cases of DLB identified clinical features that predict the presence of Lewy body disease in the brain (parkinsonism, cognitive fluctuations, hallucinations and sleep disturbances). These features were used to develop a composite risk score that would aid in determining whether underlying Lewy body pathology is contributing to dementia symptoms and improve the ability of the clinician to make a confident diagnosis of DLB.
The Composite Risk Score (Table 1) was applied to 69 well-characterized individuals, including 25 healthy controls, 24 with Alzheimer’s disease and 20 with DLB. Subjects had detailed clinical and cognitive assessments and there were no differences in age or education between the groups. Global dementia ratings revealed no differences in dementia severity between the Alzheimer’s and DLB groups. Individuals with DLB performed significantly worse in visual/spatial tests, while both groups performed similarly in global and working memory tests.
Table 1. Lewy Body Composite Risk Score
|Rate the following symptoms as being present or absent for at least three times over the past six months. Does the patient…||Yes||No|
|Have slowness in initiating and maintaining movement or have frequent hesitations or pauses during movement?|
|Have rigidity (with or without cogwheeling) on passive range of motion in any of the four extremities?|
|Have a loss of postural stability with or without frequent falls?|
|Have a tremor at rest in any of the four extremities or head?|
|Have excessive daytime sleepiness and/or seem drowsy and lethargic when awake?|
|Have episodes of illogical thinking or incoherent, random thoughts?|
|Have frequent staring spells or periods of blank looks?|
|Appear to act out his/her dreams (kick, punch, thrash, shout or scream) while still asleep?|
|Have visual hallucinations (see things not really there)?|
|Have orthostatic hypotension or other signs of autonomic insufficiency?|
© Copyright 2013 The Lewy Body Composite Risk Score James E. Galvin and New York University Langone Medical Center
Scores were significantly different in DLB patients compared to controls and those with Alzheimer’s. The Composite Risk Score discriminated between individuals likely to have underlying Lewy body disease from those who did not.
Using a cut-off of 3, the Lewy Body Composite Risk Score had a sensitivity of 90%, meaning it identified 90% of those diagnosed with Lewy body dementia. Specificity, or being correct about the diagnosis when detected, was 87%. After further analysis of the performance of individual questions, a revision to the Lewy Body Composite Risk Score led to the deletion of one question that lacked specificity, and addition of one question that improved sensitivity.
This paper first appeared online in June, 2013 in Current Translational Geriatrics and Expermental Gerontology Reports. Dr. Galvin is a member of the Lewy Body Dementia Association Board of Directors and Scientific Advisory Council.
Karantzoulis, S., & Galvin, J. (2013). Update on dementia with Lewy bodies. Current Translational Geriatrics and Experimental Gerontology Reports, 2(3), 196-204.