Challenges in Diagnosing LBD
What issues do physicians face in diagnosing LBD?
Awareness of LBD among doctors, especially primary care physicians and other general healthcare providers appears to be very limited and is likely caused by multiple factors. For example:
- A generalist needs an enormous amount of information to practice effectively in the 21st century. Their practice is typically filled with the more common, less time consuming and easily identifiable problems such as hypertension, high cholesterol, diabetes, etc. Because primary care physicians are so busy with the demands of daily practice, they may not have adequate opportunity to learn about less common disorders. This may lead them to view all dementias as due to Alzheimer’s disease (AD.)
- The complexity of understanding the full spectrum of the LBD symptoms and signs may not be practical for most general physicians. (See LBD Symptoms and Diagnosis Chart.) Despite its complexity, the four most common causes of dementia - AD, LBD, stroke and frontotemporal dementia (FTD)— could easily become core knowledge.
- Because LBD has such a wide array of non-cognitive symptoms, patients and caregivers do not know to report certain symptoms to their physician when seeking a diagnosis for cognitive decline.
- There are no widely-accessible biomarkers for LBD.
Many generalists also do not typically recognize non-tremor parkinsonism. For example, if a primary care physician sees a patient who is slow and stiff, but has no tremor, the physician might see him just as an older patient who is slow and stiff. In reality, he might have parkinsonism. It is important to heighten awareness that parkinsonism comes in different shapes and sizes and the combination of parkinsonism and dementia should raise the flag of LBD.
Raising awareness and diagnostic rates of LBD will require a multi-pronged approach:
- Preparing a simplified list of LBD symptoms specifically for use by primary care physicians, to enable them to more readily identify possible cases of LBD and refer them to a specialist for further evaluation
- Because caregivers are highly motivated and persistent in seeking a diagnosis, educating them about the disease will encourage them to report all LBD symptoms to their doctors, and also likely drive physicians to learn more about LBD.
- Adding more information on dementia to the curricula of most internal medicine residency training programs, or medical school courses is encouraged.
- Non-physician healthcare personnel should be educated as well. Nurses, nurse practitioners, physician assistants, social workers or the other allied health professionals were educated to symptoms and signs, they could be the vanguard for recognizing these disorders.
Beyond basic awareness, some physicians don’t feel that the cost-benefit ratio for treating dementia patients is favorable. This is due, in part, to the modest response to cholinesterase inhibitors and memantine in Alzheimer’s patients. LBD is a multi-system disorder, affecting motor, cognitive, behavioral, sleep, and autonomic systems. Broadening physicians’ and caregiver’s understanding of how to identify and manage the symptoms that respond to interventions may lead to improvement in the patient’s and family’s quality of life.
What symptoms are not usually reported at time of diagnosis?
Nearly all LBD patients exhibit some form of sleep disorder, including restless legs syndrome, REM sleep behavior disorder, nocturnal leg cramps, and sleep apnea. Unfortunately, few patients and caregivers know to report these symptoms to their physician when seeking an explanation for cognitive decline. All patients and their sleep partners should be asked about sleep issues, and referred to a sleep specialist for a polysomnogram when appropriate.
Several studies showed that patients with Lewy body dementia/Lewy body disease had a tendency to have more abnormalities in the electrocardiogram (ECG), especially an abnormal Q-T interval. This has been reported in patients who never complained of chest pain or other cardiovascular problems. The presence of low uptake in a myocardial scintigraphy has been included in the recently revised criteria for DLB as a supportive feature. In the context of the person who’s having autonomic dysfunction, an ECG is warranted before prescribing atypical antipsychotics.
Source: "Current Issues in LBD Diagnosis, Treatment and Research" by James E. Galvin, MD, Bradley F. Boeve, MD, John E. Duda, MD, Douglas R. Galasko, MD, Daniel Kaufer, MD, James B. Leverenz, MD, Carol F. Lippa, MD, Oscar L. Lopez, MD, representing the Scientific Advisory Council of the Lewy Body Dementia Association. May, 2008