2016 Alzheimer's disease facts and figures

https://escholarship.org/content/qt1r33f4p8/qt1r33f4p8.pdf?t=qho8bi

Dementia prevention, intervention, and care: 2020 report of the Lancet Commission.

This report provides information to increase understanding of the public health impact of Alzheimer's disease (AD), including incidence and prevalence, mortality rates, health expenditures and costs of care, and effect on caregivers and society in general. It also explores the roles and unique challenges of long‐distance caregivers, as well as interventions that target those challenges. An estimated 5.2 million Americans have AD. Approximately 200,000 people younger than 65 years with AD comprise the younger onset AD population; 5 million comprise the older onset AD population. Throughout the coming decades, the baby boom generation is projected to add about 10 million to the total number of people in the United States with AD. Today, someone in America develops AD every 68 seconds. By 2050, one new case of AD is expected to develop every 33 seconds, or nearly a million new cases per year, and the total estimated prevalence is expected to be 13.8 million. AD is the sixth leading cause of death in the United States and the fifth leading cause of death in Americans age 65 years or older. Between 2000 and 2010, the proportion of deaths resulting from heart disease, stroke, and prostate cancer decreased 16%, 23%, and 8%, respectively, whereas the proportion resulting from AD increased 68%. The number of deaths from AD as determined by official death certificates (83,494 in 2010) likely underrepresents the number of AD‐related deaths in the United States. A projected 450,000 older Americans with AD will die in 2013, and a large proportion will die as a result of complications of AD. In 2012, more than 15 million family members and other unpaid caregivers provided an estimated 17.5 billion hours of care to people with AD and other dementias, a contribution valued at more than $216 billion. Medicare payments for services to beneficiaries age 65 years and older with AD and other dementias are three times as great as payments for beneficiaries without these conditions, and Medicaid payments are 19 times as great. Total payments in 2013 for health care, long‐term care, and hospice services for people age 65 years and older with dementia are expected to be $203 billion (not including the contributions of unpaid caregivers). An estimated 2.3 million caregivers of people with AD and other dementias live at least 1 hour away from the care recipient. These “long‐distance caregivers” face unique challenges, including difficulty in assessing the care recipient's true health condition and needs, high rates of family disagreement regarding caregiving decisions, and high out‐of‐pocket expenses for costs related to caregiving. Out‐of‐pocket costs for long‐distance caregivers are almost twice as high as for local caregivers.

2013 Alzheimer's disease facts and figures

https://www.commed.vcu.edu/Chronic_Disease/2012/cochranrvwrschbias.pdf

The Cochrane Collaboration's tool for assessing risk of bias in randomised trials

https://www.thelancet.com/pdfs/journals/lancet/PIIS0140-6736(13)60688-1.pdf

Delirium in elderly people

BACKGROUND Delirium is common after cardiac surgery and may be associated with long-term changes in cognitive function. We examined postoperative delirium and the cognitive trajectory during the first year after cardiac surgery. METHODS We enrolled 225 patients 60 years of age or older who were planning to undergo coronary-artery bypass grafting or valve replacement. Patients were assessed preoperatively, daily during hospitalization beginning on postoperative day 2, and at 1, 6, and 12 months after surgery. Cognitive function was assessed with the use of the Mini– Mental State Examination (MMSE; score range, 0 to 30, with lower scores indicating poorer performance). Delirium was diagnosed with the use of the Confusion Assessment Method. We examined performance on the MMSE in the first year after surgery, controlling for demographic characteristics, coexisting conditions, hospital, and surgery type. RESULTS The 103 participants (46%) in whom delirium developed postoperatively had lower preoperative mean MMSE scores than those in whom delirium did not develop (25.8 vs. 26.9, P<0.001). In adjusted models, those with delirium had a larger drop in cognitive function (as measured by the MMSE score) 2 days after surgery than did those without delirium (7.7 points vs. 2.1, P<0.001) and had significantly lower postoperative cognitive function than those without delirium, both at 1 month (mean MMSE score, 24.1 vs. 27.4; P<0.001) and at 1 year (25.2 vs. 27.2, P<0.001) after surgery. With adjustment for baseline differences, the between-group difference in mean MMSE scores was significant 30 days after surgery (P<0.001) but not at 6 or 12 months (P = 0.056 for both). A higher percentage of patients with delirium than those without delirium had not returned to their preoperative baseline level at 6 months (40% vs. 24%, P = 0.01), but the difference was not significant at 12 months (31% vs. 20%, P = 0.055). CONCLUSIONS Delirium is associated with a significant decline in cognitive ability during the first year after cardiac surgery, with a trajectory characterized by an initial decline and prolonged impairment. (Funded by the Harvard Older Americans Independence Center and others.)

/pdf/cognitive-trajectories-after-postoperative-delirium-2jh55j2072.pdf

Cognitive Trajectories after Postoperative Delirium

Delirium is a common and serious acute neuropsychiatric syndrome with core features of inattention and global cognitive dysfunction. The etiologies of delirium are diverse and multifactorial and often reflect the pathophysiological consequences of an acute medical illness, medical complication or drug intoxication. Delirium can have a widely variable presentation, and is often missed and underdiagnosed as a result. At present, the diagnosis of delirium is clinically based and depends on the presence or absence of certain features. Management strategies for delirium are focused on prevention and symptom management. This article reviews current clinical practice in delirium in elderly individuals, including the diagnosis, treatment, outcomes and economic impact of this syndrome. Areas of future research are also discussed.

/pdf/delirium-in-elderly-adults-diagnosis-prevention-and-27g6hdarxu.pdf

Delirium in elderly adults: diagnosis, prevention and treatment.

Importance Delirium is defined as an acute disorder of attention and cognition. It is a common, serious, and often fatal condition among older patients. Although often underrecognized, delirium has serious adverse effects on the individual’s function and quality of life, as well as broad societal effects with substantial health care costs. Objective To summarize the current state of the art in diagnosis and treatment of delirium and to highlight critical areas for future research to advance the field. Evidence Review Search of Ovid MEDLINE, Embase, and the Cochrane Library for the past 6 years, from January 1, 2011, until March 16, 2017, using a combination of controlled vocabulary and keyword terms. Since delirium is more prevalent in older adults, the focus was on studies in elderly populations; studies based solely in the intensive care unit (ICU) and non–English-language articles were excluded. Findings Of 127 articles included, 25 were clinical trials, 42 cohort studies, 5 systematic reviews and meta-analyses, and 55 were other categories. A total of 11 616 patients were represented in the treatment studies. Advances in diagnosis have included the development of brief screening tools with high sensitivity and specificity, such as the 3-Minute Diagnostic Assessment; 4 A’s Test; and proxy-based measures such as the Family Confusion Assessment Method. Measures of severity, such as the Confusion Assessment Method–Severity Score, can aid in monitoring response to treatment, risk stratification, and assessing prognosis. Nonpharmacologic approaches focused on risk factors such as immobility, functional decline, visual or hearing impairment, dehydration, and sleep deprivation are effective for delirium prevention and also are recommended for delirium treatment. Current recommendations for pharmacologic treatment of delirium, based on recent reviews of the evidence, recommend reserving use of antipsychotics and other sedating medications for treatment of severe agitation that poses risk to patient or staff safety or threatens interruption of essential medical therapies. Conclusions and Relevance Advances in diagnosis can improve recognition and risk stratification of delirium. Prevention of delirium using nonpharmacologic approaches is documented to be effective, while pharmacologic prevention and treatment of delirium remains controversial.

/pdf/delirium-in-older-persons-advances-in-diagnosis-and-jfmbpwdgxu.pdf

Delirium in Older Persons: Advances in Diagnosis and Treatment.

Deficits in cholinergic function have been postulated to cause delirium and cognitive decline. This review examines current understanding of the cholinergic deficiency hypothesis in delirium by synthesizing evidence on potential pathophysiological pathways. Acetylcholine synthesis involves various precursors, enzymes, and receptors, and dysfunction in these components can lead to delirium. Insults to the brain, like ischemia and immunological stressors, can precipitously alter acetylcholine levels. Imbalances between cholinergic and other neurotransmitter pathways may result in delirium. Furthermore, genetic, enzymatic, and immunological overlaps exist between delirium and dementia related to the cholinergic pathway. Important areas for future research include identifying biomarkers, determining genetic contributions, and evaluating response to cholinergic drugs in delirium. Understanding how the cholinergic pathway relates to delirium may yield innovative approaches in the diagnosis, prevention, and treatment of this common, costly, and morbid condition.

/pdf/cholinergic-deficiency-hypothesis-in-delirium-a-synthesis-of-y7g4m1ulvi.pdf

Cholinergic deficiency hypothesis in delirium: a synthesis of current evidence.

Summary Delirium and dementia are two of the most common causes of cognitive impairment in older populations, yet their interrelation remains poorly understood. Previous studies have shown that dementia is the leading risk factor for delirium and that delirium is an independent risk factor for subsequent development of dementia. However, a major area of controversy is whether delirium is simply a marker of vulnerability to dementia, whether the effect of delirium is solely related to its precipitating factors, or whether delirium itself can cause permanent neuronal damage and lead to dementia. Ultimately, all of these hypotheses are likely to be true. Emerging evidence from epidemiological, clinicopathological, neuroimaging, biomarker, and experimental studies lends support to a strong relation between delirium and dementia, and to both shared and distinct pathological mechanisms. New preventive and therapeutic approaches that target delirium might offer a sought-after opportunity for early intervention, preservation of cognitive reserve, and prevention of irreversible cognitive decline in ageing.

/pdf/the-interface-between-delirium-and-dementia-in-elderly-20dnhq6hu1.pdf

Tamara G. Fong

Papers

Cognitive Trajectories after Postoperative Delirium

Delirium in elderly adults: diagnosis, prevention and treatment.

Delirium in Older Persons: Advances in Diagnosis and Treatment.

Cholinergic deficiency hypothesis in delirium: a synthesis of current evidence.

The interface between delirium and dementia in elderly adults