Skip to main content

Who prescribes donepezil or memantine for dementia? Not Geriatricians from the Bronx...


by: Eric Widera (@ewidera)

There are two main drug classes use to treat Alzheimer's disease, cholinesterase inhibitors (ChEIs) and the NMDA-antagonist memantine. Both have shown statistically significant improvements in outcomes for patients with AD, but the clinical significance of these benefits is marginal at best.   Furthermore, these benefits vary with disease severity, with ChEIs showing benefit from mild to servere dementia, and memantine showing benefit only in moderate to severe disease.

So how closely does clinical practice mirror the evidence behind these drugs?   A new study in JAGS suggests that your chances of being started on these drugs is about 50/50, and has less to do with FDA approved indications, and more to do with who you see and where you live.

The Study

The authors used a national sample of Medicare beneficiaries enrolled in Medicare Part D from 2008 to 2010 and evaluated the frequency of ChEI’s and mematine prescription fills in people with a diagnosis of any type of dementia.  They compared individuals with similar disease severity based on a proxy of whether the participant lived in residential care. Because the measure may be imperfect in its correlation with dementia severity, drug use according to whether the participant died within a year of index diagnosis was also reported.  Information on visits to a neurologist, psychiatrist, or geriatrician in the 2 months before and after the date of the initial diagnosis was captured as an indicator of specialty involvement.

The Results

1. About half (56%) of all people with a dementia diagnosis receive either cholinesterase-inhibitors or memantine within a year of the index diagnosis.

2. There is no difference between use of ChEI or memantine related to the study’s proxy measure for dementia severity.   Furthermore, about half (45%) of those patients with dementia who died within 1 year of their index diagnosis were on one of these agents.

3. Factors not directly related to dementia, such as race and region of residence, influence treatment rates ChEI or memantine.    Turns out Bronx, NY, has the lowest rates of using them!

4. The type of clinician involved in care may independently influence whether a person is treated with ChEI or memantine.   Neurologists and psychiatrists are more likely and geriatricians less likely to prescribe ChEI’s and memantine than when primary care manages alone.


The Take Home

Apparently, if you don't want to be put on cholinesterase inhibitors (ChEIs) or memantine, live in the Bronx and visit with a local geriatrician.  


Comments

Wonder Doc said…
So true. As a Geriatrician, I see these meds prescribed all the time for any stage or type of dementia. I usually explain to patients who see me for consultation that 'doctors like to fix things and you can't fix dementia; so they feel like they're doing something if they give you a prescription.' While, the education against the meds takes longer than most physicians have, I don't find that the limited benefits of the drugs are often clearly reviewed with or understood by these patients.

Popular posts from this blog

Dying without Dialysis

There is a terrific article in this weeks Journal of Pain and Symptom Management by Fliss Murtagh of King's College in London about the epidemiology of symptoms for patients with advanced renal failure who die without dialysis.  This study is important because while we know that patients with advanced renal failure have a limited life expectancy and the average age of initiation of hemodialysis is increasing, we know little about the alternatives to hemodialysis.  Specifically, we know nothing about symptoms affecting quality of life among patients who elect not to start dialysis (so called "conservative management" - is this the best label?).  This article provides a terrific counterpoint to the article in last years NEJM showing that nursing home residents who initiated hemodialysis tended to die and decline in function (see GeriPal write up here). 

The study authors followed patients with the most advanced form of chronic kidney disease (the new name for renal failu…

Language Matters: Podcast with Brian Block and Anna DeForest

One of our first GeriPal posts was titled "Rant on Terminology," by Patrice Villars, NP.  In the spirit of looking back over our first 10 years, here is the opening paragraph to that post:

News Headlines read: Sen. Edward Kennedy loses battle with cancer. Really, he lost? I thought he died from a malignant brain tumor, an “aggressive” brain tumor. The median survival is less than a year for people for his particular tumor. Kennedy was diagnosed in May of 2008. He lived over 15 months after diagnosis. What a loser. He must not have fought hard enough. Huh? I thought he spent most of his life battling for social and health care reform in America. In this week's GeriPal podcast we take a deeper dive into this issue of language and medicine.  We are joined by guests Anna DeForest, MD, MFA, a resident in Neurology at Yale, and Brian Block, MD, a pulmonary critical care fellow at UCSF.  

Anna recently published a paper in the NEJM describing her reaction to hearing terms like, &…

The Dangers of Fleet Enemas

The dangers of oral sodium phosphate preparations are fairly well known in the medical community. In 2006 the FDA issued it’s first warning that patients taking oral sodium phosphate preparations are at risk for potential for acute kidney injury. Two years later, over-the-counter preparations of these drugs were voluntarily withdrawn by the manufacturers.  Those agents still available by prescription were given black box warnings mainly due to acute phosphate nephropathy that can result in renal failure, especially in older adults. Despite all this talk of oral preparations, little was mentioned about a sodium phosphate preparation that is still available over-the-counter – the Fleet enema.

Why Oral Sodium Phosphate Preparations Are Dangerous 

Before we go into the risks of Fleet enemas, lets spend just a couple sentences on why oral sodium phosphate preparations carry significant risks. First, oral sodium phosphate preparations can cause significant fluid shifts within the colon …