Depression and antidepressant use moderate association between widowhood and Alzheimer's disease

Migraine and the risk of dementia: a meta-analysis and systematic review

OBJECTIVES

To conduct a comprehensive systematic review and meta-analysis to explore the correlation between migraine and the risk of dementia.

METHODS

The PubMed, EMBASE, and Cochrane library databases were searched systematically. We selected cohort studies (prospective and retrospective) and case-control studies that reported migraine in patients with dementia, including vascular dementia. The pooled effects were analyzed to evaluate relative risk with 95% confidence intervals.

RESULTS

In total, nine studies (two case-control and seven cohort studies) including 291,549 individuals were identified. These studies indicated that people with migraine (relative risk = 1.33; 95% confidence interval: 1.16-1.53) have an increased risk of all-cause dementia. Additionally, the pooled results of four studies showed that migraine is associated with an increased risk of vascular dementia (relative risk = 1.85; 95% confidence interval: 1.22-2.81; P = 0.004).

CONCLUSIONS

Data from observational studies suggest that migraine may be a risk factor for dementia, particularly vascular dementia. More studies are warranted to explore the association between migraine and dementia and the potential common pathophysiological mechanisms.

Spousal caregiving, widowhood, and cognition: A systematic review and a biopsychosocial framework for understanding the relationship between interpersonal losses and dementia risk in older adulthood

Accumulating research suggests that stressful life events, especially those that threaten close intimate bonds, are associated with an increased risk of dementia. Grieving the loss of a spouse, whether in the form of caregiving or after the death, ranks among 'life's most significant stressors', evoking intense psychological and physiological distress. Despite numerous studies reporting elevated dementia risk or poorer cognition among spousal caregivers and widow(er)s compared to controls, no review has summarized findings across cognitive outcomes (i.e., dementia incidence, cognitive impairment rates, cognitive performance) or proposed a theoretical model for understanding the links between partner loss and abnormal cognitive decline. The current systematic review summarizes findings across 64 empirical studies. Overall, both cross-sectional and longitudinal studies revealed an adverse association between partner loss and cognitive outcomes. In turn, we propose a biopsychosocial model of cognitive decline that explains how caregiving and bereavement may position some to develop cognitive impairment or Alzheimer's disease and related dementias. More longitudinal studies that focus on the biopsychosocial context of caregivers and widow(er)s are needed.

High-resolution age-specific mapping of the two-week illness prevalence rate based on the National Health Services Survey and geostatistical analysis: a case study in Guangdong province, China

BACKGROUND

The two-week illness prevalence rate is an important and comparable indicator of health service needs. High-spatial-resolution, age-specific risk mapping of this indicator can provide valuable information for health resource allocation. The age-prevalence relationships may be different among areas of the study region, but previous geostatistical models usually ignored the spatial-age interaction.

METHODS

We took Guangdong province, the province with the largest population and economy in China, as a study case. We collected two-week illness data and other potential influencing predictors from the fifth National Health Services Survey in 2013 and other open-access databases. Bayesian geostatistical binary regression models were developed with spatial-age structured random effect, based on which, high-resolution, age-specific two-week illness prevalence rates, as well as number of people reporting two-week illness, were estimated. The equality of health resource distribution was further evaluated based on the two-week illness mapping results and the health supply data.

RESULTS

The map across all age groups revealed that the highest risk was concentrated in the central (i.e., Pearl River Delta) and northern regions of the province. These areas had a two-week illness prevalence > 25.0%, compared with 10.0-20.0% in other areas. Age-specific maps revealed significant differences in prevalence between age groups, and the age-prevalence relationships also differed across locations. In most areas, the prevalence rates decrease from age 0 to age 20, and then increase gradually. Overall, the estimated age- and population-adjusted prevalence was 16.5% [95% Bayesian credible interval (BCI): 14.5-18.6%], and the estimated total number of people reporting illness within the two-week period was 17.5 million (95% BCI: 15.5-19.8 million) in Guangdong Province. The Lorenz curve and the Gini coefficient (resulted in 0.3526) showed a moderate level of inequality in health resource distribution.

CONCLUSIONS

We developed a Bayesian geostatistical modeling framework with spatial-age structured effect to produce age-specific, high-resolution maps of the two-week illness prevalence rate and the numbers of people reporting two-week illness in Guangdong province. The methodology developed in this study can be generalized to other global regions with available relevant survey data. The mapping results will support plans for health resource allocation.

Adverse life events and late-life cognitive decline in a Chinese cohort: The Shanghai Aging Study

OBJECTIVE

This study aimed to demonstrate the association between adverse life events (ALEs) and the risk of late-life cognitive decline in older community-dwelling individuals in China.

METHODS

We prospectively followed up 1657 dementia-free participants with ALE data at baseline in the Shanghai Aging Study. The cohort was categorized into four subgroups (depression with ALEs, depression without ALEs, no depression with ALEs, and no depression without ALEs). Cox regressions were conducted to estimate the hazard ratio (HR) for incident dementia stratified by all participants and depressed and nondepressed participants.

RESULTS

We identified 168 incident dementia cases over a mean period of 5.2 years. The cumulative dementia incidence in nondepressed participants with ALEs was the lowest among the four subgroups. Nondepressed participants with ALEs had a lower risk of incident dementia (HR [95% CI]: 0.50 [0.27-0.92], P = .0267) than those without ALEs, adjusted for age, sex, education, apolipoprotein E ε4 (APOE ε4), body mass index, cigarette smoking, heart disease, hypertension, diabetes, stroke, Mini-Mental State Examination (MMSE) at baseline, and anxiety.

CONCLUSIONS

This study explored a significant inverse association between ALEs and the risk of incident cognitive decline among older adults without depression in China. Interventions for depression prevention immediately after ALEs may reduce the risk of cognitive decline later in life.

Strategies for dementia prevention: latest evidence and implications

Dementia is a common and debilitating syndrome with enormous impact on individuals and societies. Preventing disease onset or progression would translate to public health and societal benefits. In this review, we discuss the latest evidence on interventions that may show promise for the prevention of cognitive decline. We appraise existing evidence primarily drawn from randomized controlled trials, systematic reviews, and meta-analyses, but also highlight observational studies in humans and relevant work in model organisms. Overall, there is currently limited evidence to support a cause-effect relationship between any preventive strategy and the development or progression of dementia. However, studies to date suggest that a multifactorial intervention comprising regular exercise and healthy diet, along with the amelioration of vascular risk factors, psychosocial stress, and major depressive episodes may be most promising for the prevention of cognitive decline. We discuss the challenges, future directions, and implications of this line of research.

Headaches and Risk of Dementia

BACKGROUND

Primary headaches include migraines, tension-type headaches and other primary headache syndromes. Migraines and tension-type headaches are associated with patient discomfort and other diseases. This study aimed to investigate the association between primary headaches and the risk of developing dementia, and to clarify the association between different types of headaches and dementia.

MATERIALS AND METHODS

We conducted a nationwide matched cohort population-based study. A total of 3,620 patients with newly diagnosed primary headaches, including migraines and tension-type headaches, between January 1 and December 31, 2000 were selected from the National Health Insurance Research Database of Taiwan, along with 10,860 controls matched for sex and age. After adjusting for confounding factors, Fine and Gray׳s competing risk analysis was used to compare the risk of developing dementia during 10 years of follow-up.

RESULTS

Of the study subjects, 170 (4.70 %) developed dementia compared with 433 (3.99%) of the controls. Fine and Gray׳s competing risk analysis revealed that the study subjects were more likely to develop dementia (hazard ratio = 2.057; 95% CI: 1.718-2.462; P < 0.001). After adjusting for sex, age, monthly income, urbanization level, geographic region of residence and comorbidities, the hazard ratio for dementia was 2.048 (95% CI: 1.705-2.461, P < 0.001). Migraines and tension-type headaches were associated with nonvascular dementia but not vascular dementia.

CONCLUSIONS

The patients with headaches had a 105% increased risk of dementia. Further studies are needed to elucidate the underlying mechanisms.

Family Member Deaths in Childhood Predict Systemic Inflammation in Late Life

Biological and epidemiological evidence has linked early-life psychosocial stress with late-life health, with inflammation as a potential mechanism. We report here the association between familial death in childhood and adulthood and increased levels of high-sensitivity C-reactive protein (CRP), a marker of systemic inflammation. The Cache County Memory Study is a prospective study of persons initially aged 65 and older in 1995. In 2002, there were 1,955 persons in the study with data on CRP (42.3 percent male, mean [SD] age = 81.2 [5.8] years), linked with objective data on family member deaths. Using logistic regression, high (> 10 mg/L) versus low (≤ 10 mg/L) CRP was regressed on cumulative parental, sibling, spouse, and offspring deaths during childhood and during early adulthood, adjusted for family size in each period (percentage family depletion; PFD). Findings revealed PFD during childhood to be significantly associated with CRP (OR = 1.02, 95% CI [1.01, 1.04]). Individuals with two or more family deaths were 79 percent more likely to have elevated CRP than those with zero family deaths (OR = 1.79, 95% CI [1.07, 2.99]). Early adulthood PFD was not related to CRP. This study demonstrates a link between significant psychosocial stress in early life and immune-inflammatory functioning in late life, and suggests a mechanism explaining the link between early-life adversity and late-life health.

Family member deaths across adulthood predict Alzheimer's disease risk: The Cache County Study

OBJECTIVES

Parental death during childhood, and offspring and spouse death during adulthood have individually been associated with faster cognitive decline and higher Alzheimer's disease (AD) risk in late life. However, the cumulative effect of childhood and adulthood family deaths on AD risk among different age cohorts has not been studied.

METHODS

To examine these associations, this prospective cohort study uses a population-based sample of 4545 initially non-demented participants (56.7% female; age M = 75.0/SD = 6.9 years) observed at four triennial waves, linked with objective Utah Population Database data on cumulative mother, father, sibling, spouse, and offspring death experienced during childhood and adulthood. Cox regression modeled survival time from baseline interview to AD onset, as a function of family deaths during childhood or adulthood, among different age groups, along with gender and presence of ε4 allele at apolipoprotein E (APOE) polymorphic genetic locus.

RESULTS

Age group significantly moderated the relationship between family death and AD; among persons aged 65-69 years at baseline (children of the Great Depression), those exposed to 3-4 deaths and 5+ deaths during adulthood exhibited a doubling of AD risk (adjusted hazard ratio, aHR = 2.25, p = .038, and aHR = 2.72, p = .029), while among persons aged 80 years and older, those exposed to 3-4 deaths during adulthood exhibited lower AD risk (HR = 0.539, p = 0.014). In a combined model of childhood and adulthood deaths, these findings persisted.

CONCLUSIONS

Results suggest a cohort effect in the link between family member deaths during adulthood and AD risk later in life.