A Risk Factor Analysis of Cognitive Impairment in Elderly Patients with Chronic Diseases in a Chinese Population

[Risk factors associated with cognitive impairment in aged: Cross-sectional study]

Background

With the increase in life expectancy, conditions related to older age have increased in incidence, one of these pathologies is Cognitive Impairment (CI), which has a prevalence of up to 28%, conditions that increase the presence of CI are known. However, there is controversy about the factors that increase the risk of CI.

Objective

To determine the factors associated with cognitive impairment in older adults.

Material and methods

We conducted a cross-sectional, analytical, observational, retroprolective study that included adults ≥65 years of age, with no history of cerebral vascular event, cranioencephalic trauma. Demographic factors were analyzed, CI was assessed with the Mini Mental State Examination test. For statistical analysis we used Odds Ratio (OR) and 95% confidence interval (95% CI) for each factor and multiple logistic regression as multivariate analysis.

Results

420 older adults were included, 61% were women, 32.6% with age >75 years, 84.5% with schooling <9 years, in the multiple logistic regression the following were independent factors for the presence of mild CI: dependence on basic activities of daily living (ADLs) with OR 5.88, absence of cognitive stimulation RM 4.50, age >75 years OR 2.92, polypharmacy OR 2.16, uncontrolled blood pressure OR 1.92.

Conclusion

ADLs dependence, absence of cognitive stimulation, age >75 years, polypharmacy and uncontrolled blood pressure are risk factors associated with CI in older adults.

The Relationship of Age-Related Hearing Loss with Cognitive Decline and Dementia in a Sinitic Language-Speaking Adult Population: A Systematic Review and Meta-Analysis

Background and Objectives

Substantial evidence supports the association between untreated hearing loss, cognitive decline, and dementia in the non-tonal language-speaking population. Whether a similar association between hearing loss and cognitive decline and dementia exists in Sinitic tonal language-speaking people is yet to be elucidated. We aimed to systematically review the current evidence on the association between hearing loss and cognitive impairment/decline, and dementia in older adults who speak a Sinitic tonal language.

Research Design and Methods

This systematic review considered peer-reviewed articles that employed objective or subjective hearing measurement and cognitive function, cognitive impairment, or diagnosis of dementia. All articles written in English and Chinese and published before March 2022 were included. Databases including Embase, MEDLINE, Web of Science, PsycINFO and Google Scholar, SinoMed, and CBM were utilized using MeSH terms and keywords.

Results

Thirty-five articles met our inclusion criteria. Of these, 29 unique studies with an estimated 372,154 participants were included in the meta-analyses. Among all included studies, the effect size of cognitive function with hearing loss, the regression coefficient was -0.26 (95% confidence interval [CI], -0.45 to -0.07). Among cross-sectional and cohort studies, a significant association was found between hearing loss and cognitive impairment and dementia, with odds ratios of 1.85 (95% CI, 1.59-2.17) and 1.89 (95% CI, 1.50-2.38), respectively.

Discussion and Implications

Most of the studies included in this systematic review observed a significant association between hearing loss and cognitive impairment and dementia. There was no significant difference to the findings in non-tonal language populations.

Visual Restoration after Cataract Surgery Promotes Functional and Structural Brain Recovery

Background

Visual function and brain function decline concurrently with aging. Notably, cataract patients often present with accelerated age-related decreases in brain function, but the underlying mechanisms are still unclear. Optical structures of the anterior segment of the eyes, such as the lens and cornea, can be readily reconstructed to improve refraction and vision quality. However, the effects of visual restoration on human brain function and structure remain largely unexplored.

Methods

A prospective, controlled clinical trial was conducted. Twenty-six patients with bilateral age-related cataracts (ARCs) who underwent phacoemulsification and intraocular lens implantation and 26 healthy controls without ARC, matched for age, sex, and education, were recruited. Visual functions (including visual acuity, visual evoke potential, and contrast sensitivity), the Mini-Mental State Examination and functional magnetic resonance imaging (including the fractional amplitude of low-frequency fluctuations and grey matter volume variation) were assessed for all the participants and reexamined for ARC patients after cataract surgery. This trial was registered with ClinicalTrials.gov (NCT02644720).

Findings

Compared with the healthy controls, the ARC patients presented decreased brain functionality as well as structural alterations in visual and cognitive-related brain areas preoperatively. Three months postoperatively, significant functional improvements were observed in the visual and cognitive-related brain areas of the patients. Six months postoperatively, the patients' grey matter volumes in these areas were significantly increased. Notably, both the function and structure in the visual and cognitive-related brain areas of the patients improved significantly and became comparable to those of the healthy controls 6 months postoperatively.

Interpretation

We demonstrated that ocular reconstruction can functionally and structurally reverse cataract-induced brain changes. The integrity of the eye is essential for maintaining the structure and function of the brain within and beyond the primary visual pathway.

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Cataract patients with reduced visual function presented a simultaneous decrease in brain function and grey matter volume.

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Cataract surgery can reverse cerebral changes in both visual and cognitive-related regions associated with visual decline.

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The integrity of the eye is essential for maintaining the structure and function of the brain.

The eyes and brain are anatomically and functionally connected. Age related cataract (ARC) is associated with structural and functional impairments of the brain. However, whether these changes are reversible after cataract surgery is largely unknown. We assessed the patients based on subjective cognitive evaluations and objective functional magnetic resonance imaging before and after surgery. Significant improvements in brain function and increases in the grey matter volumes of the visual, cognitive-related, and somatosensory brain areas were observed, demonstrating that the impaired brain function and structure of ARC patients can be reversed after restoration of visual acuity.