Factors Predicting the Onset of Amnestic Mild Cognitive Impairment or Alzheimer's Dementia in Persons With Subjective Cognitive Decline

Impact of tobacco smoking on disease-specific outcomes in common neurological disorders: A scoping review

Although the association of smoking with the risk of incident neurological disorders is well established, less is known about the impact of smoking and smoking cessation on outcomes of these conditions. The objective of this scoping review was to synthesize what is known about the impact of smoking and smoking cessation on disease-specific outcomes for seven common neurological disorders. We included 67 studies on the association of smoking and smoking cessation on disease-specific outcomes. For multiple sclerosis, smoking was associated with greater clinical and radiological disease progression, relapses, risk for disease-related death, cognitive decline, and mood symptoms, in addition to reduced treatment effectiveness. For stroke and transient ischemic attack, smoking was associated with greater rates of stroke recurrence, post-stroke cardiovascular outcomes, post-stroke mortality, post-stroke cognitive impairment, and functional impairment. In patients with cognitive impairment and dementia, smoking was associated with faster cognitive decline, and smoking was also associated with greater cognitive decline in Parkinson's disease, but not motor symptom worsening. Patients with amyotrophic lateral sclerosis who smoked faced increased mortality. Last, in patients with cluster headache, smoking was associated with more frequent and longer cluster attack periods. Conversely, for multiple sclerosis and stroke, smoking cessation was associated with improved disease-specific outcomes. In summary, whereas smoking is detrimentally associated with disease-specific outcomes in common neurological conditions, there is growing evidence that smoking cessation may improve outcomes. Effective smoking cessation interventions should be leveraged in the management of common neurological disorders to improve patient outcomes.

Subjective Aging Difficulties among Older Adults with Subjective Cognitive Decline

In older adults, subjective cognitive decline (SCD) may progress to an early stage of dementia. Yet, its association with subjective daily functional difficulties in aging is less well studied by experiences of mentally unhealthy days (MUDs). Employing a cross-sectional design approach, we analyzed the Behavioral Risk Factor Surveillance System dataset on 7429 older adults with SCD (aged 65 to >80, 45% males, 55% females) to explore SCD in instrumental daily activities of living (SCD-IADLs) and healthcare access mediation by MUDs and moderated mediation by age cohort, controlling gender and education. The bias-corrected percentile bootstrap with 5000 samplings revealed that MUDs partially mediate the relationship between SCD-IADLs and healthcare access, with a 28.2% mediating effect. Age cohort moderated the relationship between healthcare access and MUDs, MUDs and SCD-IADLs. Specifically, the predictive effects from healthcare access to MUDs and MUDs to SCD-IADLs were more profound in the 70-74 age cohort.

Subjective Functional Difficulties and Subjective Cognitive Decline in Older-Age Adults: Moderation by Age Cohorts and Mediation by Mentally Unhealthy Days

Background and Objectives: Despite the expected positive association between subjective functional difficulties (SFD) and subjective cognitive decline (SCD), their mediation by mentally unhealthy days (MUDs) is under-studied. Moreover, few SCD studies have examined affective reactivity to functional difficulties by age cohort. This study examined the mediation effect of MUDs on the association between SFD and SCD by age cohorts' moderation among older adults. Methods: Using a cross-sectional design approach, we used the 2019 BRFSS dataset on 13,377 older adults aged 65 to ≥80 (44% males and 56% females). Results: The bias-corrected percentile bootstrap with 5000 samplings revealed that MUDs partially mediate the relationship between SFD and SCD (14.12% mediation effect), controlling depressive symptoms, education, income levels, and race. Age cohorts moderated the relationship between SFD and SCD and between SFD and SCD but not between MUDs and SCD. The predictive effects of the path from SFD to MUDs and from MUDs to SCD were stronger in the younger-old (65-69) than the middle-old (70-79) and oldest-old (≥80) age cohorts. Worse SCD was associated with being Asian, in female older adults, and in those with lower education and income levels. Conclusions: These findings extend the chronic stress theory predictions that accentuated emotional vulnerability to subjective functional difficulties may magnify SCD, particularly in the younger-old age group. By implication, preventive SCD interventions should seek to support younger-old adults in their activities of daily life for successful aging transitioning into older-age cohorts.

Daily Living Subjective Cognitive Decline Indicators in Older Adults with Depressive Symptoms: A Scoping Review and Categorization Using Classification of Functioning, Disability, and Health (ICF)

(1) Background: This scoping review identifies subjective cognitive decline (SCD) indicators in ADLs and instrumental activities of daily living (IADLs) in older adults with depressive symptoms using the WHO International Classification of Functioning, Disability, and Health (ICF). (2) Methods: We searched Medline via Ebscohost, Pubmed, and PsycINFO for articles published on activities of daily living (ADL) indicators of SCD in older adults with depressive symptoms, published in English language journals from January 2011 to November 2021. Following the flow diagram, 2032 titles and abstracts were screened for relevance based on the Population, Concept, and Context inclusion and exclusion criteria. (3) Results: Eight articles provided evidence about the ADL indicators of SCD in older adults with depressive symptoms. The analysis yielded indicators based on low and high cognitively demanding tasks assessed on five different scales. Framed on the ICF categorization and coding system, the SCD-ADL indicators are personal care, mobility, and general tasks and demands; SCD-IADL indicators are mobility, general tasks and demands, learning and applying knowledge, domestic life, communication, major life areas, and community, social, and civic life. (4) Conclusion: Highly cognitively demanding activities present more difficulties for individuals with SCD, making IADLs a stronger predictor of SCD than ADLs.

Longitudinal Cognitive Profiles by Anxiety and Depressive Symptoms in American Older Adults With Subjective Cognitive Decline

PURPOSE

The objective of this study was to determine how anxiety and/or depressive symptoms differentially affect specific cognitive domains over time in persons with subjective cognitive decline (SCD).

DESIGN

A longitudinal, observational study was conducted using data from the National Alzheimer's Coordinating Center-Uniform Data Set. Mean follow-up was 4.1 ± 2.4 years.

METHODS

Using information from a total of 1401 participants (age 74.0 ± 8.2 years), linear mixed-effects regression models were used to assess longitudinal changes in global cognition, episodic memory, attention, language, and executive function by baseline psychological (anxiety [A] and/or depressive [D]) symptoms in individuals with SCD. Reference was the group having no symptoms (A-/D-).

FINDINGS

The A+/D- group was not associated with any cognitive changes. The A-/D+ group was associated with a greater decline in episodic memory and executive function. The A+/D+ group had a greater decline in attention. Changes in global cognition and language were not predicted by any psychological symptoms.

CONCLUSIONS

Depressive symptoms predicted lower episodic memory and executive function.

CLINICAL RELEVANCE

Nurses need to pay attention to depressive symptoms in older adults with SCD because managing depressive symptoms may help protect against cognitive decline more typical of early Alzheimer's dementia.

Factors predicting episodic memory changes in older adults with subjective cognitive decline: A longitudinal observational study

Episodic memory is affected early in the neuropathological process of Alzheimer's dementia. This study was performed to identify longitudinal associations between baseline vascular/neuropsychiatric risk factors and episodic memory changes over 4.1 ± 2.4 years in 1,401 older adults with subjective cognitive decline (age 74.0 ± 8.2 years). Data were from the National Alzheimer's Coordinating Center-Uniform Data Set and linear mixed effects regression models were used. Reference was those without risk factors. Participants with hypercholesterolemia and with former cigarette smoking had higher episodic memory scores, but current smokers had fewer points than reference at their first and follow-up visits. Despite no difference at baseline, episodic memory scores decreased in those with depressive symptoms relative to reference over time. In older adults with subjective cognitive decline, interventions managing current smoking and depressive symptoms could preserve episodic memory, which may result in delaying the onset of Alzheimer's dementia. Further research is required for the role of cholesterol and smoking.