Factors affecting usage patterns of memantine in Alzheimer disease

Mapping racial and ethnic healthcare disparities for persons living with dementia: A scoping review

INTRODUCTION

We set out to map evidence of disparities in Alzheimer's disease and Alzheimer's disease related dementias healthcare, including issues of access, quality, and outcomes for racial/ethnic minoritized persons living with dementia (PLWD) and family caregivers.

METHODS

We conducted a scoping review of the literature published from 2000 to 2022 in PubMed, PsycINFO, and CINAHL. The inclusion criteria were: (1) focused on PLWD and/or family caregivers, (2) examined disparities or differences in healthcare, (3) were conducted in the United States, (4) compared two or more racial/ethnic groups, and (5) reported quantitative or qualitative findings.

RESULTS

Key findings include accumulating evidence that minoritized populations are less likely to receive an accurate and timely diagnosis, be prescribed anti-dementia medications, and use hospice care, and more likely to have a higher risk of hospitalization and receive more aggressive life-sustaining treatment at the end-of-life.

DISCUSSION

Future studies need to examine underlying processes and develop interventions to reduce disparities while also being more broadly inclusive of diverse populations.

Racial/ethnic disparities in initiation and persistent use of anti-dementia medications

BACKGROUND

Racial/ethnic disparities in anti-dementia medications use in longitudinally followed research participants are unclear.

METHODS

The study included initially untreated participants followed in National Alzheimer's Coordinating Center Uniform Data Set who were ≥65 at baseline with Alzheimer's disease dementia.

OUTCOMES

Outcomes for acetylcholinesterase inhibitor (AChEI) treatment included (1) any new AChEI treatment during follow-up, and (2) persistence of treatment during follow-up categorized into: intermittent treatment (< 50% follow-ups reporting treatment), persistent (≥50% follow-ups), and always treated. Outcomes for memantine treatment were similarly constructed.

RESULTS

Controlling for participant characteristics, Black and Hispanic participants remained less likely than White participants to report any new AChEI or memantine treatment during follow-up. Among those who reported new treatment during follow-up, both Black and Hispanic participants were less likely than White participants to be persistently treated with AChEI and memantine.

DISCUSSION

Substantial racial/ethnic treatment disparities remain in controlled settings of longitudinal research in which participants have access to dementia experts, suggesting wider disparities in the larger community.

Black and White individuals differ in dementia prevalence, risk factors, and symptomatic presentation

INTRODUCTION

Although dementia prevalence differs by race, it remains unclear whether cognition and neuropsychiatric symptom severity differ between Black and White individuals with dementia.

METHODS

Using National Alzheimer's Coordinating Center (NACC) data, we evaluated dementia prevalence in non-Hispanic Black and White participants and compared their clinicodemographic characteristics. We examined race differences in cognition, neuropsychiatric symptoms, and functional abilities in participants with dementia using multivariable linear and logistic regression models.

RESULTS

We included 5,700 Black and 31,225 White participants across 39 Alzheimer's Disease Research Centers. Of these, 1,528 (27%) Black and 11,267 (36%) White participants had dementia diagnoses. Despite having lower dementia prevalence, risk factors were more prevalent among Black participants. Black participants with dementia showed greater cognitive deficits, neuropsychiatric symptoms/severity, and functional dependence.

DISCUSSION

Despite lower dementia prevalence, Black participants with dementia had more dementia risk factors, as well as greater cognitive impairment and neuropsychiatric symptom severity than White participants.

Framework for creating storytelling materials to promote African American/Black adult enrollment in research on Alzheimer's disease and related disorders

INTRODUCTION

African American/Black adults are severely underrepresented in basic, clinical, and behavioral research studies in Alzheimer's disease and related disorders (ADRD). Innovative, evidence-based, and culturally salient strategies can maximize the recruitment of African American/Black adults into ADRD research.

METHODS

We conducted and analyzed semi-structured interviews to capture the research participation stories of African American/Black participants and study partners from the University of Pittsburgh's Alzheimer's Disease Research Center. The themes and messaging principles generated through this process informed the development of video- and text-based materials that were evaluated for community member acceptance using focus groups.

RESULTS

Focus group individuals (N = 36) generally favorably rated the video and text materials, characterizing them as "interesting," "realistic," and "convincing."

DISCUSSION

Capturing the narratives of African American/Black research participants is a critical component to developing culturally relevant materials for broader dissemination and is essential to advancing beyond information-only recruitment approaches, which tend to rely disproportionately on negative messages.

Racial and Ethnic Differences in Initiation and Discontinuation of Antidementia Drugs by Medicare Beneficiaries

OBJECTIVES

To examine racial and ethnic differences in initiation and time to discontinuation of antidementia medication in Medicare beneficiaries.

DESIGN

Retrospective cohort study.

SETTING

Secondary analysis of 2009-10 enrollment, claims, and Part D prescription data for a 10% national sample of U.S. Medicare fee-for-service beneficiaries.

PARTICIPANTS

Beneficiaries aged 65 and older with Alzheimer's disease or related dementia (ADRD) before 2009 and no fills for antidementia medications in the first half of 2009 (N = 84,043).

MEASUREMENTS

Initiation was defined as having one or more fills for antidementia medication in the second half of 2009 and discontinuation as a gap in coverage of 30 days or more during the year after initiation. The Andersen Behavioral Model was used to guide covariate selection.

RESULTS

Overall, 3,481 (4.1%) of previous nonusers initiated antidementia medication in the second half of 2009. Of those initiating one drug class (acetylcholinesterase inhibitors (AChEIs) or memantine), 9% later added the other class, and 2% switched classes. Of initiators, 23% discontinued within 1 month, and 62% discontinued within 1 year. Hispanic beneficiaries were more likely than white beneficiaries to initiate (adjusted odds ratio = 1.25, 95% confidence interval (CI) = 1.10-1.41). Black and white beneficiaries did not differ in likelihood of initiation. Hispanic (adjusted hazard ratio (aHR) = 1.56, 95% CI = 1.34-1.82) and black (aHR = 1.25, 95% CI = 1.08-1.44) beneficiaries discontinued at a faster rate than white beneficiaries.

CONCLUSION

Initiation of antidementia medications was no different in black and white beneficiaries and more likely in Hispanic beneficiaries; black and Hispanic beneficiaries discontinued at a faster rate. More research into reasons explaining these differences is needed.

Racial and ethnic disparities in Alzheimer's disease pharmacotherapy exposure: an analysis across four state Medicaid populations

BACKGROUND

Treatment disparities in Alzheimer's disease (AD) have received little attention. Determining whether disparities exist in this subpopulation is an important health policy issue.

OBJECTIVE

The aim was to determine whether an association existed between race/ethnicity and exposure to AD pharmacotherapy across 4 state Medicaid populations.

METHODS

Data from the Centers for Medicare and Medicaid Services (CMS) were used in this retrospective study. Persons with AD enrolled in California, Florida, New Jersey, or New York Medicaid programs on January 1, 2004, and remained in that program for 1 year. Individuals had an AD diagnosis based on the ICD-9-CM code 331.0. Outcomes of interest were exposure to a cholinesterase inhibitor (ChEI) or memantine. Multivariate logistic regression was used to test for the association between race/ethnicity and exposure to a ChEI or memantine. Variables of interest included demographic characteristics and resource utilization factors. The Oaxaca-Blinder decomposition method was used to test for disparities to determine whether exposure to AD pharmacotherapy was influenced by race.

RESULTS

Race, age, long-term care admittance, inpatient care admittance, state of residence, and sex were significant predictors of AD pharmacotherapy exposure (P < 0.0001 for all variables). Racial/ethnic disparities were observed with respect to exposure to a ChEI or memantine between non-Hispanic whites and Hispanics (in favor of Hispanics) in Florida (P < 0.0001), between non-Hispanic blacks and Hispanics (in favor of Hispanics) in California (P < 0.0001) and Florida (P < 0.0001), between non-Hispanic blacks and non-Hispanic others (in favor of non-Hispanic others) in California (P < 0.0001) and New York (P < 0.0001), and between Hispanics and non-Hispanic others (in favor of non-Hispanic others) in California (P = 0.001) and New York (P < 0.0001).

CONCLUSIONS

Disparities in AD pharmacotherapy exposure among minority populations are just as prevalent, if not of greater magnitude, than minority/white disparities.

Barriers and facilitators of African American participation in Alzheimer disease biomarker research

African Americans experience a greater risk of Alzheimer disease (AD), but are underrepresented in AD research. Our study examined barriers and facilitators of AD research participation among African Americans. Investigators conducted 11 focus groups with African American participants (n=70) who discussed barriers and facilitators to AD research participation including lumbar puncture studies. The moderator and comoderator independently reviewed the transcripts, identified themes, and coded transcripts for analysis. Participants were predominately female (73%) with a mean age of 52 years (range 21 to 86 y). Concerns and attitudes were consistent across education, socioeconomic status, and sex. Mistrust was a fundamental reason for nonparticipation. Additional barriers included insufficient information dissemination in the African American community, inconvenience, and reputation of the researcher and research institution. Barriers to participation in AD biomarker studies were fear of the unknown and adverse effects. Altruism and relevance of research projects to the individual, family members, or the African American community facilitate participation. Increased participation results from relationships with the community that extend beyond immediate research interests, dissemination of research findings, and emphasis on relevance of proposed studies. Pervasive barriers impede African American participation in AD research but can be overcome through a sustained presence in the community.

Are patients whose study partners are spouses more likely to be eligible for Alzheimer's disease clinical trials?

BACKGROUND/AIMS

Alzheimer's disease (AD) clinical trials enroll two participants: a patient and a study partner. The primary caregiver most often fills the role of study partner and most trial study partners are spousal caregivers.

METHODS

AD trial inclusion criteria were applied to baseline data from 5,674 probable AD dementia research participants in the National Alzheimer's Coordinating Center Uniform Data Set. Eligibility was compared among patients with spousal, adult child, and other types of study partners.

RESULTS

Patients with spousal study partners were more frequently eligible than patients with adult child study partners. Compared to patients with spousal study partners, patients with adult child study partners were more frequently ineligible because of age, residence in skilled nursing facility, low scores on the Mini-Mental State Examination, highscores on the Hachinski Ischemia Scale, and failure to fulfill a minimum number of weekly visits with the study partner.

CONCLUSIONS

In this sample, patients with adult child study partners were less likely to qualify for AD clinical trials than were patients with spousal study partners. This may contribute to the lower representation of patients with adult child caregivers in these studies.

Cholinesterase inhibitor and memantine use in newly admitted nursing home residents with dementia

OBJECTIVES

To quantify the use of cholinesterase inhibitors (ChEIs) and memantine in nursing home (NH) residents with dementia upon NH admission and 3 months later and to examine factors associated with reduction in therapy.

DESIGN

Retrospective cohort study.

SETTING

Nationwide sample of U.S. NHs.

PARTICIPANTS

Three thousand five hundred six NH residents with dementia newly admitted in 2006.

MEASUREMENTS

Data from pharmacy dispensing records were used to determine ChEI and memantine medication use upon NH admission and at 3-month follow-up. The Minimum Data Set was used to determine resident- and facility-level characteristics. Severity of dementia was defined using the Cognitive Performance Scale (CPS).

RESULTS

Overall, 40.1% (n=1,407) of newly admitted NH residents with dementia received ChEIs and memantine on NH admission. Use of ChEIs and memantine on admission was significantly greater in residents with mild to moderately severe dementia (41.2%) than in those with advanced dementia (33.3%, P=.001). After 3 months, ChEI and memantine use decreased by about half in both groups (48.6% with mild to moderately severe dementia vs 57.0% with advanced dementia, P<.05). NH residents with advanced dementia were significantly more likely reduce their use of ChEIs and memantine than those with mild to moderately severe dementia (odds ratio=1.44, 95% confidence interval=1.03-2.01, P=.04).

CONCLUSION

Many NH residents with advanced dementia receive ChEIs and memantine upon NH admission, and approximately half of these decrease their medication use over the ensuing months. Further study is required to optimize use of ChEIs and memantine in NH populations and to determine the effects of withdrawing therapy on resident outcomes.

Memantine: a treatment for Alzheimer’s disease with a new formulation

In nearly 20 years, aside from cholinesterase inhibitors, memantine is the only drug approved for the treatment of Alzheimer’s disease (AD). Memantine is an uncompetitive N-methyl-D-aspartate receptor antagonist that blocks pathological glutamate activity while permitting normal physiological function, thus preventing glutamate-induced excitotoxicity. Three Phase III pivotal trials demonstrated memantine’s efficacy in treating moderate-to-severe AD, which led to its initial approval by the EMA in 2002 and US FDA in 2003. The recommended target dose is 10 mg twice daily. The US FDA recently approved an extended-release (ER) formulation of memantine for once-daily 28-mg dosing. Memantine ER was evaluated in a 24-week placebo-controlled trial of patients with moderate-to-severe AD, which found significant benefits for cognition, global assessment, behavior and caregiver burden, but not function. The most common adverse events were headache, dizziness, diarrhea, hypertension, anxiety and influenza. Overall, memantine in all formulations has a favorable safety/tolerability profile and is safe to use with cholinesterase inhibitors. Memantine ER has yet to be evaluated against conventionally dosed immediate-release memantine.

Clinic visits and prescribing patterns among Veterans Affairs Maryland Health Care System dementia patients

OBJECTIVE

Our objective was to determine how patient demographics and outpatient referrals to specialized dementia (DEM) or mental health (MH) clinics influence receipt of anti-dementia (AD), antidepressant (ADEP), antipsychotic (APSY) and sedative-hypnotic (SEDH) medications among veterans with dementia.

DESIGN

Retrospective, cross-sectional observational study.

SETTING

Veterans Affairs Maryland Health Care System (VAMHCS).

PARTICIPANTS

Veterans aged ≥ 60 years with Alzheimer's or related dementia diagnosis after 1999 with minimum of one-year follow-up or death were included.

MEASUREMENTS

Retrospective analysis of VAMHCS electronic medical records were used to determine predictors of AD, ADEP, APSY, and SEDH prescribing using logistic regression models that examined visits to DEM or MH clinics, patient age, follow-up time, race/ethnicity and marital status.

RESULTS

Among 1209 veterans with average follow-up of 3.2 (SD 1.9) years, 36% percent had MH visits, 38% had DEM visits and 19% visited both clinics. DEM visits were associated with AD and ADEP but not APSY medication receipt (OR(AD:DEM) = 1.47, 95% CI = (1.052, 2.051); OR(ADEP:DEM) = 1.66, 95% CI = (1.193, 2.302); OR(APSY:DEM) = 1.35, 95% CI = (0.941, 1.929)). MH visit was associated with ADEP and APSY medication receipt (OR(AD:MH)\ = 1.16, 95% CI = (0.821, 1.631); OR(ADEP:MH) = 2.83, 95% CI = (2.005, 4.005); OR (APSY:MH) = 4.41, 95% CI = (3.109, 6.255)).

CONCLUSION

In the VAMHCS dementia population, visits to DEM or MH specialty clinics increase the odds of receiving AD, ADEP, and APSY medications.

Pharmacological treatment of Alzheimer's disease: effect of race and demographic variables

Existing research shows differences in medication use for Alzheimer's disease (AD) based on demographics such as race, ethnicity, and geographical location. To determine individual and community characteristics associated with differences in acetylcholinesterase inhibitor (AChEI) and memantine use in AD, 3,049 AD subjects were drawn from 30 centers and evaluated using the Uniform data set (UDS). Cases were evaluated at the individual level within the context of 31 communities (one center encompassed two separate geographical regions). Multivariate analysis was used to determine the significance of individual variables on medication use. Compared to non-Hispanic Whites, Blacks were less likely to use AChEI and memantine with odds ratios (OR) of 0.59 (95% CI 0.46-0.76) and 0.43 (95% CI 0.32-0.57), respectively. Compared to non-Hispanic Whites, non-Black Hispanics were less likely to use memantine (OR=0.69 (95% CI 0.49-0.98)). No association was found between the proportion of Blacks or non-Black Hispanics versus non-Hispanic Whites at an Alzheimer Disease Center and individual use of AChEI or memantine. Other significant variables include gender, age, marital status, dementia severity, source of referral, AChEI use, and education. Education and age somewhat mitigated disparity. Significant racial and ethnic differences in AChEI and memantine use exist at the individual level regardless of the racial and ethnic composition of the individual's community. Research and initiatives at the societal level may be an important consideration toward addressing these differences.

Memantine and acetylcholinesterase inhibitor treatment in cases of CDR 0.5 or questionable impairment

The biological meaning of uncertain dementia ratings (CDR 0.5) and its treatment implications are unclear. Our study examines the frequency of anti-dementia medication use in individuals with CDR 0.5 and the cognitive, behavioral, and demographic factors associated with memantine and acetylcholinesterase inhibitor (AChEI) use. Subjects were drawn from the National Alzheimer Coordinating Center database, which collects data from 30 Alzheimer Disease Centers. There were 2,512 subjects with the following diagnoses: Normal, 11.8%; Mild cognitive impairment, 44.6%; Alzheimer's disease, 34.9%; and other dementias, 8.7%. Overall, 35% used AChEIs and 13% used memantine. AChEI and memantine use was greater in subjects who were referred by clinics and diagnosed with Alzheimer's disease. AChEI use was associated with being married, younger, male, and more educated while memantine use was associated with less severe apathy and other dementia diagnosis. Non-Hispanic whites were more likely to use AChEI and memantine than non-Hispanic blacks (OR = 2.2, 2.5). Hispanics were more likely to use AChEI than non-Hispanic blacks. It appears anti-dementia medication use in CDR 0.5 is frequent and represents evidence for extensive off label usage. Diagnosis, severity of impairment, and race, among other variables, affect the likelihood of AChEI and memantine use in this population.