Study explores links between people taking multiple medications and dementia diagnosis

by University of Plymouth

Credit: CC0 Public Domain

People with dementia are likely to have taken more than three medications for other health conditions in the five years directly before their diagnosis, according to new research.

05 nov 2022--The study is the first to provide an in-depth exploration of the links between evolving polypharmacy—which involves a patient being prescribed more than one drug at any given time—and a dementia diagnosis.

Published in the Aging and Disease journal, it is based on an analysis of the records of more than 33,000 dementia patients in Wales between 1990 to 2015.

Experts in e-health used machine learning techniques to identify potentially damaging patterns in a patient's medicine usage, and how these patterns evolve in the run-up to diagnosis.

They found that in the 20 years leading up to them being diagnosed, the proportion of patients taking three or more medications rose from 5.5% (for the period 16 to 20 years prior to diagnosis) to 82.16% among those less than five years from a diagnosis.

Researchers also found that as the development towards dementia progressed, the patterns of polypharmacy shifted from being clearly distinct to being more closely associated with particular medical conditions.

And of those closest to their diagnosis, almost two-thirds (66.55%) were found to be taking multiple medicines for a combination of respiratory or urinary infections, arthropathies and rheumatism, and cardio-vascular disease. A further 22% of patients were found to be taking medicines for infections, arthropathies and rheumatism, cardio-metabolic disease and depression.

The study was supported by the Health Data Research UK and conducted by an international team of researchers from the University of Plymouth, Aptuit (an Evotec company), Swansea University Medical School, and the University of Oxford.

Shangming Zhou, Professor of e-Health at the University of Plymouth, led the study. He said: "Given the rise in dementia cases internationally, the need to understand how patterns of polypharmacy evolve before and after a dementia diagnosis are important for devising a safe treatment program for each patient. Our aim in this study was to help doctors find ways to prescribe multiple items of dementia medication safely and without reducing their effectiveness. The use of machine learning has been vital in helping us understand how these patterns develop, and our hope is we can now use this knowledge to treat patients."

It has previously been established that when multiple types of preventative medication are being prescribed, the benefits of the drugs may be reduced and the chances of harm from drug interaction and side effects increased.

Those requiring hospital treatment who are taking multiple medications are also known to have a higher likelihood of re-admission within three months after being discharged.

With the number of people with dementia in the UK projected to rise to 1.6 million by 2040, researchers hope this new study will inform safe prescribing practices and encourage doctors to prescribe medicine combinations developed with a view to minimizing cognitive impairments.

More information: Identifying Dynamic Patterns of Polypharmacy for Patients with Dementia from Primary Care Electronic Health Records: A Machine Learning Driven Longitudinal Study, Aging and Disease (2022). DOI: 10.14336/AD.2022.0829

Provided by University of Plymouth 

PET scans may improve accuracy of dementia diagnosis

PET scans critical for early, accurate diagnosis and treatment of dementia, say researchers at SNM's 56th Annual Meeting

TORONTO, 18 june 2009—A new study shows that the use of positron emission tomography (PET) scans may improve the accuracy of dementia diagnoses early in disease onset for more than one out of four patients. The results were presented at SNM's 56th Annual Meeting.

Early, accurate diagnosis of dementia is critical for providing the best available courses of treatment and therapies in the beginning stages of disease, when treatments can be most effective. PET scans enable physicians to identify the neurological conditions underlying each patient's mental decline and choose appropriate courses of treatment.

"Routine clinical assessments do not accurately identify the root causes of dementia in the early stages," said Kirk A. Frey, a physician with the University of Michigan Hospitals' Division of Nuclear Medicine and lead author of the study. "Our preliminary results clearly indicate that molecular imaging technologies, such as PET scans, can help diagnose a patient's specific type of dementia. This is critical for providing the best possible care. Additionally, PET's ability to pinpoint neurological underpinnings of different forms of dementia could lead to new, more targeted drugs and therapies."

More than 5 million people each year are newly diagnosed with dementia, a disease that takes many forms and includes memory loss or other mental impairments that interfere with daily life. The most common type of dementia is Alzheimer's disease. Other types include frontotemporal dementia, which affects the frontal and temporal lobes of the brain, and Lewy body dementia, which involves degeneration of dopamine nerves in addition to the temporal and parietal lobes. Although these types of dementia have different causes, patients can express similar symptoms in the early stages, making accurate diagnosis difficult. Providing appropriate treatments and therapies as early as possible can avoid unnecessary, and sometimes severe, side-effects and complications.

The new study identified 66 patients with mild dementia or mild cognitive impairment who were evaluated through standard neurological testing and anatomic brain imaging. Three clinical experts reviewed the results of these data to make diagnoses of either Alzheimer's disease, frontotemporal dementia or dementia with Lewy bodies. Patients then underwent PET scans for amyloid deposits and for dopamine nerve integrity. Patients' initial diagnoses changed more than 25 percent of the time after PET imaging. PET scans provided images of important signals for disease that other examinations missed, such as deposits of amyloid plaque, which are a common indicator of Alzheimer's disease, and damage to dopamine nerves in Lewy body dementia.

The study will track patients for two years to confirm the accuracy of their diagnoses.

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Scientific Paper 251: K. Frey, J. Burke, B. Giodani, R. Koeppe, R. Albin, The University of Michigan, Ann Arbor, MI; "PET neurochemical vs. clinical phenotypes in mild-early dementia," SNM's 56th Annual Meeting, June 13-17, 2009.

About SNM—Advancing Molecular Imaging and Therapy

SNM is an international scientific and medical organization dedicated to raising public awareness about what molecular imaging is and how it can help provide patients with the best health care possible. SNM members specialize in molecular imaging, a vital element of today's medical practice that adds an additional dimension to diagnosis, changing the way common and devastating diseases are understood and treated.