Physical status and dementia risk: a three-year prospective study in urban Japan

Associations of Lung Function Decline with Risks of Cognitive Impairment and Dementia: A Meta-Analysis and Systematic Review

BACKGROUND

There are controversies surrounding the effects of lung function decline on cognitive impairment and dementia.

OBJECTIVE

We conducted a meta-analysis and systematic review to explore the associations of lung function decline with the risks of cognitive impairment and dementia.

METHODS

The PubMed, EMBASE, and the Cochrane Library were searched to identify prospective studies published from database inception through January 10, 2023. We pooled relative risk (RR) and 95% confidence intervals (CI) using random-effects models. The Egger test, funnel plots, meta-regression, sensitivity, and subgroup analyses were conducted to detect publication bias and investigate the source of heterogeneity.

RESULTS

Thirty-three articles with a total of 8,816,992 participants were subjected to meta-analysis. Poorer pulmonary function was associated with an increased risk of dementia (FEV: RR = 1.25 [95% CI, 1.17-1.33]; FVC: RR = 1.40 [95% CI, 1.16-1.69]; PEF: RR = 1.84 [95% CI, 1.37-2.46]). The results of the subgroup analyses were similar to the primary results. Individuals with lung diseases had a higher combined risk of dementia and cognitive impairment (RR = 1.39 [95% CI, 1.20-1.61]). Lung disease conferred an elevated risk of cognitive impairment (RR = 1.37 [95% CI, 1.14-1.65]). The relationship between lung disease and an increased risk of dementia was only shown in total study participants (RR = 1.32 [95% CI, 1.11-1.57]), but not in the participants with Alzheimer's disease (RR = 1.39 [95% CI, 1.00-1.93]) or vascular dementia (RR = 2.11 [95% CI, 0.57-7.83]).

CONCLUSION

Lung function decline was significantly associated with higher risks of cognitive impairment and dementia. These findings might provide implications for the prevention of cognitive disorders and the promotion of brain health.

Elder Care in Iran: A Case with a Unique Demographic Profile

Iran will encounter rapid population aging, resulting from increased life expectancy and fluctuating fertility rates during its eight-year war with Iraq (1980-1988). The need for long-term care in Iran is expected to increase dramatically. The purpose of this paper is to examine Iran's health care system and informal care upon discussing its demographic profile. Scant attention of policymakers on the country's demographic transformation has resulted in limited resources for quality elder care as well as budget constraints for relevant research. In this demographic and political context, the costs of formal care, the shortage of health workforce and infrastructures (i.e., long-term care facilities), and the continuation of traditional cultural values are the most significant reasons for heavy reliance on informal elder care. In addition to inadequate systemic support, the prevalence of domestic violence, abuse, and infantalization are largely attributable to insufficient knowledge among informal elder carers.

Respiratory Disease and Lower Pulmonary Function as Risk Factors for Dementia: A Systematic Review With Meta-analysis

BACKGROUND

In addition to affecting the oxygen supply to the brain, pulmonary function is a marker of multiple insults throughout life (including smoking, illness, and socioeconomic deprivation). In this meta-analysis of existing longitudinal studies, the hypothesis that lower pulmonary function and respiratory illness are linked to an elevated risk of dementia was tested.

METHODS

A systematic review was conducted of longitudinal studies using PubMed until April 1, 2019, and, where possible, results were pooled in random effects meta-analyses.

RESULTS

Ten studies relating pulmonary function to later dementia risk and 11 studies of respiratory illness and dementia (including one that assessed both factors) were identified. The lowest quartile of FEV₁ compared with the highest was associated with a 1.4-fold (hazard ratio [HR], 1.46; 95% CI, 0.77-2.75) increased dementia risk (N_total = 62,209; two studies). A decrease of 1 SD in FEV₁ was associated with a 28% increase in dementia risk (HR, 1.28; 95% CI, 1.03-1.60; N_total = 67,505; six studies). Respiratory illness was also associated with increased dementia risk to a similar degree (pooled HR, 1.54; 95% CI, 1.30-1.81; N_total = 288,641; 11 studies).

CONCLUSIONS

Individuals with poor pulmonary function experience an increased risk of dementia. The extent to which the association between poor pulmonary function and dementia is causal remains unclear and requires examination.

Affective disorders and risk of developing dementia: systematic review

BACKGROUND

Affective disorders are associated with cognitive disturbances but their role as risk factors for dementia is still not fully investigated.

AIMS

To evaluate the risk of developing dementia in individuals with a history of affective disorder.

METHOD

We conducted a systematic review of case-control and cohort studies addressing the risk of developing dementia in people with affective disorders. To the best of our knowledge, this is the first systematic review that has included studies evaluating this risk specifically in people with bipolar disorder.

RESULTS

Fifty-one studies were included. Most of the studies found an increased risk for developing dementia in individuals with depression. Greater frequency and severity of depressive episodes seem to increase this risk. The evidence is contradictory regarding whether there is a difference in risk in people with early- or late-onset depression. The few available risk estimates for dementia in people with bipolar disorder suggest an even higher risk than for those with depression.

CONCLUSIONS

Affective disorders appear to be associated with an increased risk of developing dementia, and one that is dependent on clinical and demographic variables. Depression may be both a prodrome and a risk factor for dementia. Future research should aim to elucidate the mechanisms that mediate these links.

Development of simple cognitive function measures in a community dwelling population of elderly in Spain

OBJECTIVE

To develop and assess the consistency and validity of simple cognitive function measures for an elderly population with low levels of formal education for use in a longitudinal study of dementia.

METHODS

Data were from the population longitudinal study 'Growing old in Leganés' (Spain). In 1993, a random sample of 1540 people over 65 was drawn from the City Roll of Leganés from which 1284 (83%) were successfully interviewed. Measures of memory and orientation were based on the SPMSQ (Short Portable Mental Status Questionnaire), the Barcelona test and the short story from EPESE (Established Populations Epidemiologic Studies of the Elderly). Non-response to a test item was coded as an error. Internal consistency was assessed by factor analysis and Cronbach's alpha. Construct validity was examined with multiple linear regressions of the proposed measurements on variables chosen from the existing literature on cognitive function.

RESULTS

Two factors, memory and orientation, emerged from the factor analysis. Internal consistency of the proposed indexes for memory and orientation was acceptable. Memory and orientation scores were summed into one summary index of cognition. Associations between covariates and both cognitive indexes were in the expected direction. Among those highly functional, orientation was influenced by illiteracy due to higher error rates in the time orientation items based on dates; however, memory and summary scores were not significantly different by literacy status. A large proportion of the variance in IADL was explained by the memory and orientation measures.

CONCLUSION

The memory and orientation indexes are valid and reliable measurements of cognitive function for use in a population of community dwelling elderly with low levels of formal education and high rates of illiteracy.