VANCOUVER, British Columbia — Researchers are working to develop cognitive assessments to test for the early detection of neurodegenerative disease, as reported by investigators at the 2016 annual meeting of the American Academy of Neurology (AAN). Their aim is to create assessments and guidelines that are consistent across practices and that are efficient to conduct in clinical practice.
“Currently in the United States, the majority of patients suspected to have a neurodegenerative disease are identified, evaluated, diagnosed, and cared for by primary care physicians (PCPs). However, due to gaps in PCPs’ knowledge of these conditions and heterogeneity of approaches across clinicians and sites, many patients are missed at the mild cognitive impairment (MCI) phase, do not undergo timely or appropriate diagnostic procedures, are miscategorized, and are not referred to a neurology specialist when clinically warranted,” wrote Katherine Rankin, PhD, a professor in the Department of Neurology at the University of California, San Francisco, and colleagues.
“Screening for cognitive deficits is essential in neurodegenerative disease,” wrote David R. Roalf, PhD, a cognitive neuroscientist at the Perelman School of Medicine at the University of Pennsylvania, and colleagues. “Screening tests such as the Montreal Cognitive Assessment (MoCA) are easily administered, correlate with neuropsychological performance, and demonstrate diagnostic utility. Yet, administration time is suboptimal in many clinical settings.”
Dr Roalf and his colleagues developed a short form of the MoCA by employing item response theory and computerized adaptive testing simulation in 1850 participants with and without neurodegenerative disease.
The investigators identified 8 MoCA items with high item discrimination and appropriate difficulty for use in a short- form test (s-MoCA). The s-MoCA was highly correlated with the original MoCA (Pearson’s r=0.959 [95% confidence interval]: 0.956-0.962), showed robust diagnostic classification, and was substantiated with cross-validation procedures.
“Administration of screening measures [for cognitive impairment] is limited by time constraints in demanding clinical settings. Here, we provide a short form of the MoCA that is valid across neurological disorders and can be administered in approximately 5 minutes,” wrote Dr Roalf and colleagues.
In order to create a standard set of guidelines for dementia evaluation to prevent missing diagnosis at the MCI phase, Dr Rankin and a panel of experts in dementia diagnosis and care (neurologists, neuropsychologists, psychiatrists, geriatricians, PCPs, and nurses) convened in March 2015 to determine a standard approach for dementia assessment and screening. The panel members continue to refine these guidelines and are currently writing a consensus paper.
The panelists agreed upon a tiered approach including the following steps:
- At a wellness visit with a PCP, patients older than age 65 receive minimal screening questions typically included in standard wellness visits.
- Patients with concerns have a problem-focused, brain-health visit with their PCP; at this visit, targeted questions, cognitive screening, laboratory assessment, and in select cases neuroimaging are used to determine if MCI or dementia is present.
- When a neurodegenerative condition is suspected, a dementia diagnostic visit with either a PCP or specialist is conducted. This visit includes targeted questions, cognitive testing, laboratory assessment, and neuroimaging focusing on the correct differential diagnosis of dementia.
- When symptoms have progressed rapidly, a visit with the PCP (including specific questions, laboratory assessment, and decision procedures) is conducted to rule out common causes of delirium.
- In rapidly progressive dementia, a comprehensive visit for patients who are not delirious is conducted by a neurologist.
“We report guidelines for a tiered approach to evaluating patients at early stages of neurodegenerative disease, intended to enhance clinician proficiency and promote effective and efficient patient care,” wrote Dr Rankin and colleagues.
“Early detection of cognitive impairment is becoming an important clinical and public health concern,” wrote Dr Roalf. He and his colleagues noted that benefits of the early detection of cognitive impairment include: identifying clinical and daily functioning concerns such as falls or driving; providing patients and their families an opportunity to plan ahead medically, financially, and legally; reducing long-term healthcare costs; and offering early screening once disease-modifying therapies for neurocognitive disease become available.
References
- Roalf D, Moore TM, Wolk D, et al. Defining and validating a short form Montreal Cognitive Assessment (s-MoCA) for use in neurodegenerative disease. Presented at: The 68th Annual Meeting of the American Academy of Neurology. April 15-21, 2016; Vancouver, British Columbia, Canada. Presentation S1.005.
- Rankin K, Possin K, Geschwind M, et al. Development of an expert consensus approach to screening, assessment, and diagnosis of patients at risk for neurodegenerative disease. Presented at: The 68th Annual Meeting of the American Academy of Neurology. April 15-21, 2016; Vancouver, British Columbia, Canada. Presentation S1.006.