Subjective memory complaints are not increased in type 2 diabetes: A matched cohort study

Prevalence and Factors Associated with Subjective Memory Complaint in a Semi-Rural Community in Chile

BACKGROUND

Subjective memory complaints (SMC) are commonly studied in older adults and have been identified as potentially prodromal to dementia and Alzheimer's disease. Studies among younger adults from South America are lacking.

OBJECTIVE

To estimate the prevalence of SMC and the factors associated with it among Maule Cohort (MAUCO) participants.

METHODS

We performed a cross-sectional analysis to estimate the prevalence of SMC and investigated its associated factors from MAUCO baseline data (N = 6,687). Within groups defined by age (38-59, 60-74) and global cognition (Mini-Mental State Examination: ≥26, 25-22, ≤21), multinomial logistic regression models evaluated risk factors for SMC (Yes, Sometimes, No).

RESULTS

Overall, SMC prevalence was 16.4%; 15.9% (95% CI 14.9-16.9%) among younger and 17.6% (15.8-19.4%) among older participants. Female sex, comorbidities, and bad/fair self-reported health status (SRHS) were generally associated with higher odds of SMC.

CONCLUSION

Overall prevalence of SMC was 16%. Different factors were associated with the odds of SMC depending on age and global cognitive status. Future SMC studies should include sex-specific assessments, evaluate SRHS as a moderator of SMC reporting, and the influence of the SARS-CoV-2 pandemic on SMC reporting.

Tractography in Type 2 Diabetes Mellitus With Subjective Memory Complaints: A Diffusion Tensor Imaging Study

The brain white matter (WM) structural injury caused by type 2 diabetes mellitus (T2DM) has been linked to cognitive impairment. However, the focus was mainly on the mild cognitive impairment (MCI) stage in most previous studies, with little attention made to subjective memory complaints (SMC). The main purpose of the current study was to investigate the characteristics of WM injury in T2DM patients and its correlation with SMC symptoms. In a group of 66 participants (33 HC and 33 T2DM-S), pointwise differences along WM tracts were identified using the automated fiber quantification (AFQ) approach. Then we investigated the utility of DTI properties along major WM tracts as features to distinguish patients with T2DM-S from HC via the support vector machine (SVM). Based on AFQ analysis, 10 primary fiber tracts that represent the subtle alterations of WM in T2DM-S were identified. Lower fractional anisotropy (FA) in the right SLF tract (r = −0.538, p = 0.0013), higher radial diffusivity (RD) in the thalamic radiation (TR) tract (r = 0.433, p = 0.012), and higher mean diffusivity (MD) in the right inferior fronto-occipital fasciculus (IFOF) tract (r = 0.385, p = 0.0029) were significantly associated with a long period of disease. Decreased axial diffusivity (AD) in the left arcuate was associated with HbA_1c (r = −0.368, p = 0.049). In addition, we found a significant negative correlation between delayed recall and abnormal MD in the left corticospinal tract (r = −0.546, p = 0.001). The FA of the right SLF tracts and bilateral arcuate can be used to differentiate the T2DM-S and the HC at a high accuracy up to 88.45 and 87.8%, respectively. In conclusion, WM microstructure injury in T2DM may be associated with SMC, and these abnormalities identified by DTI can be used as an effective biomarker.

Cognitive complaints in age-related chronic conditions: A systematic review

INTRODUCTION

Cognitive complaints in older adults may be indicative of progressive cognitive decline including Alzheimer's disease (AD), but also occur in other age-related chronic conditions, complicating identification of early AD symptoms. To better understand cognitive complaints in aging, we systematically reviewed the evidence to determine their prevalence and characterization among older adults with the most common age-related chronic conditions.

METHODS

This systematic review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement and the review protocol was prospectively registered with PROSPERO (ID: CRD42020153147). Searches were conducted in PubMed, CINAHL, PsycINFO, Web of Science, and ProQuest Dissertations & Theses A&I in June 2020. Two members of the review team independently determined article eligibility for inclusion and conducted quality appraisal. A narrative synthesis of results was used to integrate findings across studies and draw conclusions regarding the strength of the evidence in each chronic condition category.

RESULTS

Thirty-seven articles met eligibility criteria and were included in the review. Conditions represented were diabetes (n = 20), heart disease (n = 13), hypertension (n = 10), chronic lung disease (n = 5), arthritis (n = 4), heart failure (n = 2), and hyperlipidemia (n = 2). In addition, 16 studies included a measure of multimorbidity. Overall, there was a higher prevalence of cognitive complaints in individuals with higher multimorbidity, including a potential dose-dependent relationship. Findings for specific conditions were inconsistent, but there is evidence to suggest that cross-sectionally, older adults with diabetes, heart disease, chronic lung disease, and arthritis have more cognitive complaints than those without these conditions.

CONCLUSION

There is strong evidence demonstrating that cognitive complaints are more common in older adults with higher multimorbidity, but little research examining these associations over time. Improving our understanding of the longitudinal trajectory of cognitive complaints, multimorbidity, and objective cognition in older age is an important area for future research.