Estimating the Prevalence of Serious Mental Illness and Dementia Diagnoses Among Medicare Beneficiaries in the Health and Retirement Study

Exploring the relationship between lipid metabolism and cognition in individuals living with stable-phase Schizophrenia: a small cross-sectional study using Olink proteomics analysis

BACKGROUND

Cognitive impairment is a core symptom of schizophrenia. Metabolic abnormalities impact cognition, and although the influence of blood lipids on cognition has been documented, it remains unclear. We conducted a small cross-sectional study to investigate the relationship between blood lipids and cognition in patients with stable-phase schizophrenia. Using Olink proteomics, we explored the potential mechanisms through which blood lipids might affect cognition from an inflammatory perspective.

METHODS

A total of 107 patients with stable-phase schizophrenia and cognitive impairment were strictly included. Comprehensive data collection included basic patient information, blood glucose, blood lipids, and body mass index. Cognitive function was assessed using the Montreal Cognitive Assessment (MoCA) and the MATRICS Consensus Cognitive Battery (MCCB). After controlling for confounding factors, we identified differential metabolic indicators between patients with mild and severe cognitive impairment and conducted correlation and regression analyses. Furthermore, we matched two small sample groups of patients with lipid metabolism abnormalities and used Olink proteomics to analyze inflammation-related differential proteins, aiming to further explore the association between lipid metabolism abnormalities and cognition.

RESULTS

The proportion of patients with severe cognitive impairment (SCI) was 34.58%. Compared to patients with mild cognitive impairment (MCI), those with SCI performed worse in the Attention/Alertness (t = 2.668, p = 0.009) and Working Memory (t = 2.496, p = 0.014) cognitive dimensions. Blood lipid metabolism indicators were correlated with cognitive function, specifically showing that higher levels of TG (r = -0.447, p < 0.001), TC (r = -0.307, p = 0.002), and LDL-C (r = -0.607, p < 0.001) were associated with poorer overall cognitive function. Further regression analysis indicated that TG (OR = 5.578, P = 0.003) and LDL-C (OR = 5.425, P = 0.001) may be risk factors for exacerbating cognitive impairment in individuals with stable-phase schizophrenia. Proteomics analysis revealed that, compared to individuals with stable-phase schizophrenia and normal lipid metabolism, those with hyperlipidemia had elevated levels of 10 inflammatory proteins and decreased levels of 2 inflammatory proteins in plasma, with these changes correlating with cognitive function. The differential proteins were primarily involved in pathways such as cytokine-cytokine receptor interaction, chemokine signaling pathway, and IL-17 signaling pathway.

CONCLUSION

Blood lipids are associated with cognitive function in individuals with stable-phase schizophrenia, with higher levels of TG, TC, and LDL-C correlating with poorer overall cognitive performance. TG and LDL-C may be risk factors for exacerbating cognitive impairment in these patients. From an inflammatory perspective, lipid metabolism abnormalities might influence cognition by activating or downregulating related proteins, or through pathways such as cytokine-cytokine receptor interaction, chemokine signaling pathway, and IL-17 signaling pathway.

Care trajectories around a first dementia diagnosis in patients with serious mental illness

AIM

To develop a typology of care trajectories (CTs) 1 year before and after a first dementia diagnosis in individuals aged ≥65 years, with prevalent schizophrenia or bipolar disorder.

METHODS

This was a longitudinal, retrospective cohort study using health administrative data (1996-2016) from Quebec (Canada). We selected patients aged ≥65 years with an incident diagnosis of dementia between 1 January 2014 and 31 December 2016, and a diagnosis of schizophrenia and/or or bipolar disorder. A CT typology was generated by a multidimensional state sequence analysis based on the "6 W" model of CTs. Three dimensions were considered: the care setting ("where"), the reason for consultation ("why") and the specialty of care providers ("which").

RESULTS

In total, 3868 patients were categorized into seven distinct types of CTs, with varying patterns of healthcare use and comorbidities. Healthcare use differed in terms of intensity, but also in its distribution around the diagnosis. For instance, whereas one group showed low healthcare use, healthcare use abruptly increased or decreased after the diagnosis in other groups, or was equally distributed. Other significant differences between CTs included mortality rates and use of long-term care after the diagnosis. Most patients (67%) received their first dementia diagnosis during hospitalization.

CONCLUSIONS

Our innovative approach provides a unique insight into the complex healthcare patterns of people living with serious mental illness and dementia, and provides an avenue to support data-driven decision-making by highlighting fragility areas in allocating care resources. Geriatr Gerontol Int 2024; 24: 577-586.

Biomarkers of neurodegeneration in schizophrenia: systematic review and meta-analysis

QUESTION

Does neurodegenerative disease underlie the increased rate of dementia observed in older people with schizophrenia? Several studies have reported a higher prevalence of dementia in people with schizophrenia compared with the general population. This may reflect a higher risk of developing neurodegenerative diseases such as vascular dementia or Alzheimer's disease (AD). Alternatively, this may reflect non-pathological, age-related cognitive decline in a population with low cognitive reserve.

STUDY SELECTION AND ANALYSIS

We reviewed papers that compared postmortem findings, hippocampal MRI volume or cerebrospinal fluid (CSF) markers of AD, between patients with schizophrenia with evidence of cognitive impairment (age ≥45 years) with controls. We subsequently performed a meta-analysis of postmortem studies that compared amyloid-β plaques (APs) or neurofibrillary tangles (NFTs) in cognitively impaired patients with schizophrenia to normal controls or an AD group.

FINDINGS

No studies found a significant increase of APs or NFTs in cognitively impaired patients with schizophrenia compared with controls. All postmortem studies that compared APs or NFTs in patients with schizophrenia to an AD group found significantly more APs or NFTs in AD. No studies found a significant differences in CSF total tau or phosphorylated tau between patients with schizophrenia and controls. The two studies which compared CSF Aβ42 between patients with schizophrenia and controls found significantly decreased CSF Aβ42 in schizophrenia compared with controls. Hippocampal volume findings were mixed.

CONCLUSIONS

Studies have not found higher rates of AD-related pathology in cognitively impaired individuals with schizophrenia compared with controls. Higher rates of dementia identified in population studies may reflect a lack of specificity in clinical diagnostic tools used to diagnose dementia.

Race, Educational Attainment, and Sustained High Body Mass Index over 24 Years of Follow-up in Middle-Aged and Older Adults

BACKGROUND

Educational attainment has been linked to reduced risk of health problems such as obesity, but research suggests that this effect may be weaker for non-Hispanic Black individuals compared to non-Hispanic White individuals, a pattern known as minorities' diminished returns (MDRs).

OBJECTIVES

This study is aimed at examining the differential association between educational attainment and sustained high body mass index (BMI) among non-Hispanic Black and non-Hispanic White middle-aged and older adults in the USA.

METHODS

Using data from the Health and Retirement Study (HRS) spanning 1992-2016, we analyzed a national sample of 35,110 individuals, including 7766 non-Hispanic Black and 27,344 non-Hispanic White individuals. We used logistic regression models to examine the relationship between educational attainment, race, and sustained high BMI, while controlling for age, sex, and marital status at baseline.

RESULTS

Approximately 30.6% of the sample (n = 10,727) had sustained high BMI, while 69.4% (n = 24,383) had sustained low BMI over the period of follow-up. Higher levels of educational attainment were associated with a lower risk of sustained high BMI. We also found, however, that the protective effects of education against sustained high BMI were weaker for non-Hispanic Blacks compared to non-Hispanic Whites.

CONCLUSION

Our findings suggest that the protective effects of educational attainment against sustained high BMI may be more robust for non-Hispanic Whites than for non-Hispanic Blacks. Further research should explore whether these results are found in other racial and ethnic minorities and whether potential life history experiences may contribute to these disparities.

Risk factors for dementia and self-harm: A linkage study

INTRODUCTION

People living with dementia experience poor mental health and high rates of self-harm. We investigated risk factors for self-harm in people aged > 40 years living with dementia and risk factors for dementia after self-harm.

METHODS

Using linked hospital data from New South Wales, Australia, we defined a dementia cohort (n = 154,811) and a self-harm cohort (n = 28,972). Using survival analyses, we investigated predictors of self-harm for the dementia cohort, and predictors of dementia for the self-harm cohort.

RESULTS

We found self-harm or dementia diagnoses occurred most often within 24 months of a dementia diagnosis or initial self-harm presentation, respectively. Men living with dementia, and people with complex psychiatric profiles, had the greatest risk of self-harm. Men who had self-harmed had the greatest risk of dementia diagnoses.

DISCUSSION

Men and people with complex psychiatric profiles and dementia may particularly benefit from post-diagnosis mental and behavioral support to reduce risk of self-harm.

Dementia and the history of disease in older adults in community

INTRODUCTION

Many studies have revealed the effect of medical history on dementia. The aim of this study was to explore the relationship between the history of disease and onset of dementia.

METHODS

This was a multi-center, cross-sectional study, with 2595 older adults enrolled. The onset of dementia was evaluated with Revised Hasegawa Dementia Scale (HDS-R). The diagnosed diseases after the age of 40 of the participants were investigated, including respiratory system diseases, digestive system diseases, cardiovascular diseases, endocrine disorders, genitourinary system diseases, nervous system disease, sensory system diseases, dental/oral diseases, bone/joint diseases and mental illnesses.

RESULTS

Data of 2458 older adults were analyzed. Univariate analysis showed that diabetes, thyroid disease, mental illness, hearing loss, stroke, dental/oral disease, Denture use, fracture/osteoporosis, kidney disease and number of diseases were risk factors for dementia. After controlling for demographic sociological variables, diabetes, dental/oral disease, and denture use were independent risk factors for dementia. Thyroid disease (P = 0.313), mental illnesses (P = 0.067), hearing loss (P = 0.595), stroke (P = 0.538), fractures/osteoporosis (P = 0.069), kidney disease (P = 0.168) were no longer significant to dementia.

CONCLUSION

Diabetes, dental/oral disease and denture use were main risk factors for dementia.

Care Managers in the Aging Network: Increasing Self-Efficacy in Human Service Providers

One in four older adults has Behavioral Health (BH) concerns, and over 63% are not receiving services. Older adults living in the community depend on the aging network for home- and community-based services and care managers are critical providers in this network. However, most care managers' current education and training are inadequate to care for older adults with BH needs. This study evaluated the effectiveness of training on the perceived self-efficacy of care managers working with older adults with BH needs. The study used a quasi-experimental design with a pre- and post-test approach and convenience sampling (n = 90). We found a significant difference in mean self-efficacy scores, from pre-test (M = 62.31, SD = 10.11) to post-test (M = 65.88, SD = 7.40) related to working with clients with mental health problems. In addition, we found a significant difference between the mean pre-test (M = 59.81, SD = 10.68) and post-test score (M = 65.60, SD = 9.85) related to working with clients with substance use problems.

Analyzing the relationship between the personality traits of nursing students and their attitudes toward people with mental illnesses

PURPOSE

The aim is to analyze the relationship between the personality traits of nursing students and their attitudes toward people with mental illnesses.

DESIGN AND METHODS

The cross-sectional study constituted of 281 students. The Community Attitudes toward the Mentally Ill Scale and the Ten-Item Personality Inventory were used.

FINDINGS

The students who have mental illnesses or in their families showed a higher goodwill score. The openness to experience subscale was correlated with conscientiousness, extraversion, emotional stability, and agreeableness.

PRACTICE IMPLICATIONS

Organizing educational programs for nursing students focusing on developing a positive attitude toward people with mental illnesses is crucial.

Psychiatric history and later-life cognitive change: effect modification by sex, race and ethnicity

Objective: We explored associations between psychiatric history and cognitive functioning, and differences by sex and race/ethnicity (SRE) in 20,155 Health and Retirement Study (1995-2014) participants aged 65 or older.Methods: Multi-level growth curve models examined cognition scores and their trajectories over time by SRE.Results: A history of psychiatric, emotional, or nervous problems was significantly related to cognition scores and rates of decline. Hispanic and Black participants had significantly lower cognition scores at age 75 and steeper rates of decline than White females, and Black race and the Hispanic race/ethnicity-sex interaction erased the protective effects of being female.Conclusions: Future research should include specific psychiatric diagnoses. Population level findings as reported here, along with aggregate findings from similar studies, can inform interventions and policies regarding support for populations that are vulnerable to mental illness and to subsequent cognitive decline.

Schizophrenia: A developmental disorder with a risk of non-specific but avoidable decline

The onset of schizophrenia is determined by biological and social risk factors operating predominantly during development. These result in subtle deviations in brain structure and cognitive function. Striatal dopamine dysregulation follows, causing abnormal salience and resultant psychotic symptoms. Most people diagnosed as having schizophrenia do not progressively deteriorate; many improve or recover. However, poor care can allow a cycle of deterioration to be established, stress increasing dopamine dysregulation, leading to more stress consequent on continuing psychotic experiences, and so further dopamine release. Additionally, long-term antipsychotics can induce dopamine supersensitivity with resultant relapse and eventually treatment resistance. Some patients suffer loss of social and cognitive function, but this is a consequence of the hazards that afflict the person with schizophrenia, not a direct consequence of genetic predisposition. Thus, brain health and cognition can be further impaired by chronic medication effects, cardiovascular and cerebrovascular events, obesity, poor diet, and lack of exercise; drug use, especially of tobacco and cannabis, are likely to contribute. Poverty, homelessness and poor nutrition which become the lot of some people with schizophrenia, can also affect cognition. Regrettably, the model of progressive deterioration provides psychiatry and its funders with an alibi for the effects of poor care.

Neurodegenerative model of schizophrenia: Growing evidence to support a revisit

Multidimensional progressive declines in the absence of standard biomarkers for neurodegeneration are observed commonly in the development of schizophrenia, and are accepted as consistent with neurodevelopmental etiological hypotheses to explain the origins of the disorder. Far less accepted is the possibility that neurodegenerative processes are involved as well, or even that key dimensions of function, such as cognition and aspects of biological integrity, such as white matter function, decline in chronic schizophrenia beyond levels associated with normal aging. We propose that recent research germane to these issues warrants a current look at the question of neurodegeneration. We propose the view that a neurodegenerative hypothesis provides a better explanation of some features of chronic schizophrenia, including accelerated aging, than is provided by neurodevelopmental hypotheses. Moreover, we suggest that neurodevelopmental influences in early life, including those that may extend to later life, do not preclude the development of neurodegenerative processes in later life, including some declines in cognitive and biological integrity. We evaluate these views by integrating recent findings in representative domains such as cognition and white and gray matter integrity with results from studies on accelerated aging, together with functional implications of neurodegeneration for our understanding of chronic schizophrenia.

Prevalence of dementia and mild cognitive impairment before incarceration

BACKGROUND

Accumulating evidence indicates that behaviors in Alzheimer's disease and related dementias could result in incarceration. Yet, the proportion of persons diagnosed with dementia and mild cognitive impairment (MCI) before they were incarcerated is largely unknown. By leveraging a national sample of mid- to late-life adults who were incarcerated, we determined the prevalence of dementia and MCI before their incarceration.

METHODS

In this current study, participants were Medicare-eligible U.S. veterans who transitioned from incarceration to the community in mid- to late-life from October 1, 2012, to September 30, 2018, after having been incarcerated for ≤10 consecutive years (N = 17,962). Medical claims data were used to determine clinical diagnoses of dementia and MCI up to three years before incarceration. Demographics, comorbidities, and duration of incarceration among those with dementia and MCI were compared to those with neither diagnosis.

RESULTS

Participants were >97% male, 65% non-Hispanic white, 30% non-Hispanic black, and 3.3% had a diagnosis of either dementia (2.5%) or MCI (0.8%) before their most recent incarceration. Individuals with MCI or dementia diagnoses were older, were more likely to be non-Hispanic white, had more medical and psychiatric comorbidities, and experienced homelessness and traumatic brain injury at higher rates than those with neither diagnosis. Average duration of incarceration was significantly shorter among those with MCI (201.8 [±248.0] days) or dementia (312.8 [±548.3] days), as compared to those with neither diagnosis (497.0 [±692.7] days) (p < 0.001).

CONCLUSIONS

These findings raise awareness of the proportion of incarcerated persons in the United States who have a diagnosis of MCI or dementia before they are incarcerated. Improved understanding of pathways linking cognitive impairment to incarceration in mid- to late-life are needed to inform appropriateness of incarceration, optimization of health care, and prevention of interpersonal harm in this medically vulnerable population.

Age-Specific Prevalence and Incidence of Dementia Diagnoses Among Older US Adults With Schizophrenia

IMPORTANCE

People with schizophrenia are at high risk of receiving a diagnosis of dementia. Understanding the magnitude and timing of this increased risk has important implications for practice and policy.

OBJECTIVE

To estimate the age-specific incidence and prevalence of dementia diagnoses among older US adults with schizophrenia and in a comparison group without serious mental illness (SMI).

DESIGN, SETTING, AND PARTICIPANTS

This retrospective cohort study used a 50% random national sample of Medicare beneficiaries 66 years or older with fee-for-service plans and Part D prescription drug coverage from January 1, 2007, to December 31, 2017. The cohort with schizophrenia included adults with at least 12 months of continuous enrollment in fee-for-service Medicare and Part D and at least 2 outpatient claims or at least 1 inpatient claim for schizophrenia during the qualifying years. The comparison group included adults with at least 12 months of continuous enrollment in fee-for-service Medicare and Part D and without a diagnosis of schizophrenia, bipolar disorder, or recurrent major depressive disorder during the qualifying year. Data were analyzed from January 1 to July 31, 2020.

MAIN OUTCOMES AND MEASURES

Dementia was defined using the Centers for Medicare & Medicaid Services Chronic Conditions Warehouse diagnosis codes for Alzheimer disease and related disorders or senile dementia. Incident diagnoses were defined by at least 12 consecutive eligible months without a qualifying code before meeting dementia criteria.

RESULTS

The study population of 8 011 773 adults 66 years or older (63.4% women; mean [SD] age, 74.0 [8.2] years) included 74 170 individuals with a diagnosis of schizophrenia (56.6% women) and 7 937 603 without an SMI diagnosis (63.5% women) who contributed 336 814 and 55 499 543 person-years of follow-up, respectively. At 66 years of age, the prevalence of diagnosed dementia was 27.9% (17 640 of 63 287) among individuals with schizophrenia compared with 1.3% (31 295 of 2 389 512) in the group without SMI. By 80 years of age, the prevalence of dementia diagnoses was 70.2% (2011 of 2866) in the group with schizophrenia and 11.3% (242 094 of 2 134 602) in the group without SMI. The annual incidence of dementia diagnoses per 1000 person-years at 66 years of age was 52.5 (95% CI, 50.1-54.9) among individuals with schizophrenia and 4.5 (95% CI, 4.4-4.6) among individuals without SMI and increased to 216.2 (95% CI, 179.9-252.6) and 32.3 (95% CI, 32.0-32.6), respectively, by 80 years of age.

CONCLUSIONS AND RELEVANCE

In this cohort study, compared with older adults without SMI, those with schizophrenia had increased risk of receiving a diagnosis of dementia across a wide age range, possibly because of cognitive and functional deterioration related to schizophrenia or factors contributing to other types of dementia. High rates of dementia among adults with schizophrenia have implications for the course of illness, treatment, and service use.

Risk of Nursing Home Use among Older Americans: The Impact of Psychiatric History and Trajectories of Cognitive Function

OBJECTIVE

Mental illness and cognitive functioning may be independently associated with nursing home use. We investigated the strength of the association between baseline (1998) psychiatric history, eight-year cognitive function trajectories, and prospective incidence of nursing home use over a ten-year period while accounting for relevant covariates in U.S. adults aged 65 and older. We hypothesized that self-reported baseline history of psychiatric, emotional or nervous problems would be associated with greater risk of nursing home use, and that cognition trajectories with the greatest decline would be associated with subsequent higher risk of nursing home use.

METHODS

We used eight waves (1998-2016) of Health and Retirement Study data for adults aged 65 years and older. Latent class mixture modeling identified four distinct cognitive function trajectory classes (1998-2006): low-declining, medium-declining, medium-stable, high-declining. Participants from the 1998 wave (N = 5628) were classified into these four classes. Competing risks regression analysis modeled the sub-hazard of nursing home use between 2006 and 2016 as a function of baseline psychiatric history and cognitive function trajectories.

RESULTS

Psychiatric history was independently associated with greater risk of nursing home use (SHR 1.26, 95% CI 1.06-1.51, p<.01), net the effects of life course variables. Further, "low declining" (SHR 2.255, 95% CI 1.70-2.99, p<.001) and "medium declining" (2.103, 95% CI 1.69-2.61, p<.001) trajectories predicted increased risk of nursing home use.

DISCUSSION

Evidence of these associations can be used to educate policymakers and providers about the need for appropriate psychiatric training for staff in community-based and residential long-term care programs.

Health Profiles, Health Services Use, and Transition to Dementia in Inpatients With Late-Life Depression and Other Mental Illnesses

OBJECTIVES

Depression has been reported as a risk factor for dementia. We compared health and health service use profiles in older people hospitalized with late-life depression and older people hospitalized with other mental illnesses and examined the transition to dementia.

DESIGN

A retrospective population-based study using linked administrative health data over 11 years.

SETTING AND PARTICIPANTS

The sample includes 55,717 inpatients age 65+ years with depression and 104,068 inpatients age 65+ years with other mental illnesses in New South Wales, Australia.

METHODS

The risk of subsequent dementia under consideration of sociodemographics, comorbidities, and health service use was analyzed with logistic regression.

RESULTS

The most prominent differences were the rates of delirium and self-harm with a 6 times lower rate of delirium and an 8 times higher rate of self-harm in people with late-life depression compared with those with other mental illness. Inpatients with late-life depression had an increased risk of subsequent dementia by 12% and received a dementia diagnosis at a younger age compared with inpatients with other mental illnesses. Besides depression only 3 other conditions, delirium, diabetes, and cerebrovascular accidents, were associated with an increased dementia risk. Other factors associated with an increased dementia risk were longer hospital stays, low socioeconomic status, male sex, and older age.

CONCLUSIONS AND IMPLICATIONS

Results from this study lead to a better understanding of the risk for dementia and of differences in health profiles and health services use in older people with depression compared with those with other mental illnesses. Our findings highlight the importance of the clinical management and prevention of self-harm and delirium in older people.

Temporal and Geographic Variation in the Incidence of Alzheimer's Disease Diagnosis in the US between 2007 and 2014

OBJECTIVES

Our aim was to describe the incidence of Alzheimer's disease (AD) in the United States, overall and by geographic region.

DESIGN

We conducted retrospective analyses of administrative claims data for a 5% random sample of US Medicare beneficiaries aged 65 years or older. AD incidence, defined as a diagnosis for AD (International Classification of Disease, Ninth Revision, Clinical Modification code 331.0×) in a given year, with no AD diagnosis in the beneficiary's entire medical history, was estimated for each calendar year between 2007 and 2014. Beneficiaries were required to be enrolled in Medicare for the calendar year of evaluation as well as the preceding 12 months. In addition, a cross-sectional assessment of geographic variation in AD incidence was conducted for 2014. For each population area (specifically, core-based statistical area, as defined by the US Census Bureau), AD incidence was estimated overall, as well as adjusted for differences in underlying patient demographics and metrics of access to care and quality of care. Changes in AD incidence from 2007 were also estimated.

SETTING

US fee-for-service Medicare.

PARTICIPANTS

US Medicare beneficiaries aged 65 years or older with no history of AD.

RESULTS

Overall, the diagnosed incidence of AD decreased over time, from 1.53% in 2007 to 1.09% in 2014; trends were similar for most population areas. In 2014, the rates of AD incidence ranged from 0% to more than 3% across population areas, with the highest observed incidence rates in areas of the Midwest and the South. Statistical models explain little of the geographic variation, although following adjustment, the incidence rates increased the most (in relative terms) in rural areas of western states.

CONCLUSION

Our findings are consistent with previously reported estimates of incidence of AD in the United States and its recent declining trend. Additionally, the study highlights the considerable geographic variation in the incidence of AD in the United States and suggests that further research is needed to better understand the determinants of this geographic variation. J Am Geriatr Soc 68:346-353, 2020.