Each study has a usefulness score out of 100 (rubric version 4.0). Tap a score to see what makes it up.
Highest usefulness score first. Studies without a score come last.
-
61/100
Obesity in middle age increases the risk of future dementia independently of comorbid conditions.
Why it matters
This study measured body size in 10,276 people aged 40–45 in a Northern California health plan between 1964 and 1973, then tracked dementia diagnoses from 1994 to 2003; 6.9% were diagnosed. Compared with people of normal weight in midlife, those who were obese had a 74% higher risk of dementia (hazard ratio 1.74) and those who were overweight a 35% higher risk (1.35), after adjusting for factors including diabetes, high blood pressure and stroke. These are relative risks from an observational study: it shows a link between midlife weight and later dementia, and does not test whether losing weight lowers that risk.
-
Emotion-oriented care is more effective with regard to the emotional adaptation in nursing homes of persons with a mild to moderate dementia.
Why it matters
In this trial of 146 nursing home residents with dementia, integrated emotion-oriented care produced positive effects in mild to moderately demented residents on maintaining emotional balance and preserving a positive self-image, and some nursing assistants had fewer stress reactions. This is about emotional adaptation and caregiving in nursing homes, not about treating, curing, or preventing Alzheimer's disease.
-
This randomized, observer-blind, controlled trial examined the efficacy and safety of the traditional Chinese herbal medicine Yi-Gan San (YGS, Yokukan-San in Japanese) in the improvement of behavioral and psychological symptoms of dementia (BPSD) and activities of daily living (ADL).
Why it matters
This randomized, observer-blind, controlled trial gave the traditional Chinese herbal medicine Yi-Gan San or no drug for 4 weeks to 52 patients with mild-to-severe dementia, assessing behavioral and psychological symptoms and activities of daily living. It tested a treatment for symptoms in people who already have dementia, not a cure or prevention.
-
Public Psychiatric Hospital Rekem, Belgium.
Why it matters
In this small trial, 15 women with dementia did daily music-supported physical exercises for three months and were compared with 10 control patients who had daily conversation. The study looked only at mood and cognitive function during the program, so it does not show any effect on curing or preventing Alzheimer's disease.
-
Based on informant report, disturbed arousal and disorganized speech are specific aspects of fluctuations in dementia with Lewy bodies that reliably distinguish dementia with Lewy bodies from Alzheimer's disease and normal aging.
Why it matters
Family members or carers of 70 people with dementia with Lewy bodies (DLB), 70 with Alzheimer's disease and 200 healthy older adults answered a questionnaire about "fluctuations". Four features stood out: daytime drowsiness and lethargy, daytime sleep of 2 or more hours, staring into space for long periods, and episodes of disorganized speech. Three or four of them were reported for 63% of people with DLB, 12% with Alzheimer's and 0.5% of healthy adults. When three or four were reported, the clinical diagnosis was DLB rather than Alzheimer's 83% of the time. This is a diagnostic aid based on what carers report. It is not a test on its own, and it says nothing about treatment.
-
In 1996, Kanowski et al. reported about the beneficial effects of ginkgo biloba special extract EGb 761 (240 mg/day) in outpatients with pre-senile and senile primary degenerative dementia of the Alzheimer type (DAT) and multi-infarct dementia (MID) of mild to moderate severity.
Why it matters
In this 24-week trial, intention-to-treat analysis of cognitive scores indicated improvement in cognitive function for the ginkgo biloba extract EGb 761 group, while the placebo group showed only minimal change. The paper notes that comparing these results with other dementia studies is hampered because the original published analysis used a different cognitive scale.
-
There were 140,055 subjects in the 1998-1999 cohort and 146,328 in the 1999-2000 cohort, of which 55.5 percent and 59.7 percent, respectively, were immunized.
Why it matters
This study found that influenza vaccination in people aged 65 and older was associated with a reduced risk of hospitalization for cardiac disease and stroke. It did not test any treatment, cure or prevention for Alzheimer's disease, though it noted that unvaccinated subjects were more likely to have a prior diagnosis of dementia or stroke.
-
Two hundred fifteen cases of dementia and 151 cases of AD were diagnosed.
Why it matters
In a US cohort of 2,356 people aged 65 and over who were free of dementia at the start (followed from 1994), new Alzheimer's cases rose steeply with age, from 2.8 per 1,000 person-years at ages 65–69 to 56.1 per 1,000 over age 90. The authors say these rates are "consistent with recent US and European cohort studies". Older age, APOE genotype and a low starting score on a cognitive screening test were linked to higher risk; sex was not linked to Alzheimer's onset. More education was linked to lower dementia risk, but the authors caution that the screening test itself "could also be influenced by educational level".
-
The lack of effective predictors of the rate of dementia progression extends to the very earliest stages of the disease, including what is often called MCI.
Why it matters
In this longitudinal study, the rate of progression increased with dementia severity, and there was limited evidence of other predictors of progression. The authors conclude that effective predictors of the rate of dementia progression are lacking even in the earliest stages, including mild cognitive impairment.
-
61/100
Reduced exposure to environmental factors that contribute to cancer risk, tumour-suppressor genes on chromosome 21, or a slower rate of replication or higher likelihood of apoptosis in Down's syndrome cells, could be possible reasons for paucity of cancer in people with Down's syndrome.
Why it matters
This study of US death certificates found that the median age at death for people with Down's syndrome rose from 25 years in 1983 to 49 years in 1997. It does not test any treatment, cure or prevention for Alzheimer's disease, though it discusses possible reasons for a lower rate of cancer in people with Down's syndrome.
-
The average follow-up was 6.0 years.
Why it matters
This population study found that light-to-moderate drinking was associated with a lower risk of any dementia and vascular dementia, but it did not test whether alcohol prevents Alzheimer's disease. It is an observational study and does not establish that drinking alcohol treats, cures, or prevents Alzheimer's disease.
-
The field of aging and dementia is focusing on the characterization of the earliest stages of cognitive impairment.
Why it matters
This 2001 review by an international expert group defines mild cognitive impairment as memory loss greater than expected for age in people who do not meet criteria for clinically probable Alzheimer's disease, and says such people progress to probable AD at a considerably accelerated rate compared with healthy peers of the same age. It notes that the term was used inconsistently and suggests subclassifications. It states that no treatments were recommended for MCI at the time, though clinical trials were under way.
-
The possibility that history of depression is a risk factor for dementia needs to be taken seriously and explanations of the association need to be further researched.
Why it matters
Pooling seven case-control and six prospective studies, this 2001 review found that a history of depression was associated with about twice the risk of later dementia (relative risk 2.01, 95% CI 1.16–3.50, and 1.87, 95% CI 1.09–3.20), though the intervals are wide. A separate qualitative review found no explanation clearly supported; the leading candidates were that depression is an early sign of dementia, that it brings dementia on earlier, or that it damages the hippocampus through a stress-hormone (glucocorticoid) cascade. The author concludes only that the possibility "needs to be taken seriously" and that the reasons need more research, so this does not show that depression causes dementia or that treating it prevents dementia.
-
Several studies suggested that women are at higher risk of dementia than men.
Why it matters
This study investigated whether women are at higher risk of dementia than men by following 7,046 people without dementia. It examined gender differences in the occurrence of dementia, Alzheimer's disease and vascular dementia, which may inform risk awareness but does not test a treatment.
-
During 21 046 person-years of follow-up (median follow-up, 6.3 years), 199 women developed dementia, including 159 who developed AD.
Why it matters
In this population-based cohort of postmenopausal women, a longer reproductive period was not clearly associated with lower risk of dementia or Alzheimer's disease after adjusting for age. This null result does not support the idea that longer exposure to the body's own estrogens protects against dementia.
-
Individuals currently characterized as having MCI progress steadily to greater stages of dementia severity at rates dependent on the level of cognitive impairment at entry and they almost always have the neuropathologic features of AD.
Why it matters
Following 277 people rated as having mild cognitive impairment (CDR 0.5) and 177 healthy volunteers at one research centre for up to 9.5 years, this study found that within 5 years 60.5%, 35.7% and 19.9% of three MCI subgroups (graded by how confident clinicians were that Alzheimer-type dementia was present) had reached mild definite dementia, compared with 6.8% of controls. Of the 25 MCI participants examined after death, 21 (84%) had Alzheimer's disease, and the authors concluded that "MCI generally represents early-stage AD." It is an observational study of natural history and tested no treatment or prevention.
-
61/100
This study examined the temporal trends in the incidence rates of HIV dementia, cryptococcal meningitis, toxoplasmosis, progressive multifocal leukoencephalopathy, and CNS lymphoma from January 1990 to December 1998 in the Multicenter AIDS Cohort Study.
Why it matters
In the Multicenter AIDS Cohort Study from 1990 to 1998, new cases of HIV dementia, cryptococcal meningitis and CNS lymphoma decreased after highly active antiretroviral therapy (HAART) was introduced; this is a trend over time, not proof that the therapy caused the drop. The authors also report that since 1996 a growing share of new HIV dementia cases "may be" in people with higher CD4 counts (201 to 350). This is about dementia linked to HIV infection, not Alzheimer's disease, and says nothing about Alzheimer's treatment or prevention.
-
61/100
Cerebral white matter of asymptomatic people frequently exhibits circumscribed areas of hyperintensity on magnetic resonance (MR) images and hypodensity on computed tomography scans.
Why it matters
This meta-analysis found that white matter abnormalities on MRI in adults without dementia were associated with weaker performance on processing speed, immediate and delayed memory, executive functions and global cognitive functioning, with no significant link to intelligence or fine motor performance. It describes cognitive correlates of these brain changes and reports no treatment, cure or prevention.
-
Comparison of probands with their unaffected spouses yielded odds ratios for AD of 9.9 (95% CI, 6.5 to 15.1) for head injury with loss of consciousness and 3.1 (2.3 to 4.0) for head injury without loss of consciousness.
Why it matters
In this study, head injury with loss of consciousness was linked to a much higher risk of Alzheimer's disease, and head injury without loss of consciousness was linked to a smaller increase. The effect appeared greater in people lacking the APOE epsilon 4 allele.
-
Midlife hypertension is associated with later development of cognitive impairment, vascular dementia (VsD), and possibly Alzheimer's disease (AD).
Why it matters
Among 243 Japanese-American men from the Honolulu-Asia Aging Study who had autopsies, high blood pressure measured in midlife was linked to Alzheimer-type brain changes decades later. A midlife systolic pressure of 160 mm Hg or more was associated with lower brain weight and more neuritic plaques in the neocortex and hippocampus. A diastolic pressure of 95 mm Hg or more was associated with more neurofibrillary tangles in the hippocampus. The authors say this points to a direct relationship between high blood pressure and these lesions, beyond its known link to vascular damage, but this is an association in one group of men, not proof that blood pressure causes Alzheimer's.
-
The current study is a controlled clinical investigation of two nonpharmacological treatments of depression in patients with Alzheimer's disease.
Why it matters
Two behavioral treatments, one focused on pleasant events for patients and one on caregiver problem solving, reduced depression symptoms in patients with Alzheimer's disease and in their caregivers. These gains were still present six months later, suggesting behavioral approaches can help treat depression in this population.
-
61/100
In this HMO, comprehensive geriatric assessment by a consultation team, with limited follow-up, did not improve the health or survival of hospitalized patients selected on the basis of screening criteria.
-
We determined incidence and future projections of dementia after AIDS onset in 492 homosexual men with AIDS in the Baltimore/Los Angeles sites of the Multicenter AIDS Cohort Study, 64 of whom developed dementia.
Why it matters
In this cohort of men with AIDS, 15% developed dementia, with a median survival after dementia of 6.0 months. Lower pre-AIDS hemoglobin was the most significant predictor of dementia, while there were no significant risks defined from demographic characteristics, specific AIDS-defining illnesses, zidovudine use before AIDS, or CD4+ lymphocyte count before AIDS.
-
Criteria for the diagnosis of vascular dementia (VaD) that are reliable, valid, and readily applicable in a variety of settings are urgently needed for both clinical and research purposes.
Why it matters
This 1993 report from an international workshop convened by the NINDS with support from AIREN set out research criteria for diagnosing vascular dementia, intended "as a guide for case definition in neuroepidemiologic studies" at three levels of certainty: definite, probable and possible. The criteria stress that vascular dementia takes many forms, that a secure diagnosis needs a link in time between stroke and the start of dementia, and that brain imaging and memory-and-thinking tests should support the diagnosis. The authors say the criteria "await testing and validation and will be revised as more information becomes available"; the report studied no patients and gives no accuracy figures.
-
APOE ε4 carriers have increased Alzheimer's disease risk and altered omega-3 metabolism.
Why it matters
High-dose DHA supplements raised DHA levels in the spinal fluid of older adults without dementia, showing the supplement reached the brain. However, over 24 months there were no differences in cognition or brain structure, so this supplement did not affect these outcomes in this trial.
From across this topic
10 of the 7,967 studies in this topic, picked by a fixed rule (a hash of each study's address), not by score or date; each page of this list shows a different 10. The same 10 appear here every time.
- Adherence to the Mediterranean Diet and Obesity-Linked Cancer Risk in EPIC
- Nutrient intake and dietary changes during a 2-year multi-domain lifestyle intervention among older adults: secondary analysis of the Finnish Geriatric Intervention Study to Prevent Cognitive Impairment and Disability (FINGER) randomised controlled trial
- ADAS-Cog Trajectories Differ from Expected Decline in Dementia Following Repeated Non-Invasive Interventions over 3 Years
- Exercise therapy for the treatment of delirium in the intensive care unit
- Transition from mild cognitive impairment to normal cognition: Determining the predictors of reversion with multi-state Markov models
- [Effects of a neuropsychology program based on mindfulness on Alzheimer's disease: randomized double-blind clinical study]
- A Randomized Control Trial for ReDeSign: A Dementia-Friendly Mobile Microlearning Training for Store Workers in Japan
- Sleep and physical activity trade-offs and dementia risk: a prospective cohort study in UK Biobank participants
- Diabetic retinopathy as the primary predictor of mild cognitive impairment in type 2 diabetes: Insights from machine learning models
- [Neuropsychological tests of simple application for diagnosing dementia]