Biopsychosocial risk factors for subjective cognitive decline among older adults during the COVID-19 pandemic: a population-based study.

OBJECTIVES: There have been concerns that the COVID-19 pandemic and the measures used to contain it impacted the cognitive health of older adults. We therefore examined the prevalence of subjective cognitive decline, and its associated risk factors and health consequencs, among dementia-free older adults 2 years into the pandemic in Switzerland. STUDY DESIGN: Population-based cohort study. METHODS: Prevalence of SCD was estimated using the cognitive complaint questionnaire administered to adults aged ≥65 years in June-September 2022 (Specchio-COVID19 cohort, N = 1414), and compared to prepandemic values from 2014 to 2018 (CoLaus|PsyCoLaus cohort, N = 1181). Associated risk factors and health consequences were assessed using logistic and/or linear regression. RESULTS: Prevalence of SCD in 2022 (18.9% [95% CI, 16.2-21.9]) was comparable to prepandemic levels in 2014-2018 (19.5% [17.2-22.1]). Risk factors included established risks for dementia-namely health issues, health behaviours, and depressive symptoms. Self-reported post-COVID, perceived worsening of mental health since the start of the pandemic, less frequent social club attendance, and increased loneliness were also risk factors for SCD. In turn, SCD was associated with poorer objective cognitive performance, difficulty performing instrumental activities of daily living, greater risk of falls, and lower well-being at one-year follow-up. CONCLUSIONS: While the overall prevalence of SCD in 2022 was comparable to prepandemic levels, we identified several pandemic-related risk factors for SCD, including perceived worsening of mental health and increased isolation since the start of the pandemic. These findings highlight the importance of mental health promotion strategies in reducing cognitive complaints and preventing cognitive decline.

Adversity specificity and life period exposure on cognitive aging.

This study set out to examine the role of different adversities experienced at different life course stages on cognitive aging (i.e., level and change). Data from the longitudinal study: Survey of Health, Ageing, and Retirement in Europe (SHARE) with the selection of participants over 60 years were used (N = 2662, Mdnage = 68, SDage = 5.39) in a Structural Equation Modeling. In early life, the experience of hunger predicted lower delayed recall (ß = - 0.10, p < 0.001) and verbal fluency (ß = - 0.06, p = 0.001) performance in older age, whereas financial hardship predicted lower verbal fluency (ß = - 0.06, p = 0.005) performance and steeper decline in delayed recall (ß = - 0.11, p < 0.001). In early adulthood, financial hardship and stress predicted better delayed recall (financial hardship: ß = 0.08, p = 0.001; stress: ß = 0.07, p = 0.003) and verbal fluency performance (financial hardship: ß = 0.08, p = 0.001; stress ß = 0.10, p < 0.001), but no adversities were associated with a change in cognitive performance. In middle adulthood, no adversities were associated with the level of cognitive performance, but financial hardship predicted lower decline in delayed recall (ß = 0.07, p = 0.048). This study highlights the importance of disentangling the period effect from the specific effect of the adversity experienced in the association between adversity and cognition in older age. Moreover, differential results for delayed recall and verbal fluency measures suggest that it is also important to consider the cognitive outcome domains examined.

Validation of a commercially available SARS-CoV-2 serological immunoassay.

OBJECTIVES: To validate the diagnostic accuracy of a Euroimmun SARS-CoV-2 IgG and IgA immunoassay for COVID-19. METHODS: In this unmatched (1:2) case-control validation study, we used sera of 181 laboratory-confirmed SARS-CoV-2 cases and 326 controls collected before SARS-CoV-2 emergence. Diagnostic accuracy of the immunoassay was assessed against a whole spike protein-based recombinant immunofluorescence assay (rIFA) by receiver operating characteristic (ROC) analyses. Discrepant cases between ELISA and rIFA were further tested by pseudo-neutralization assay. RESULTS: COVID-19 patients were more likely to be male and older than controls, and 50.3% were hospitalized. ROC curve analyses indicated that IgG and IgA had high diagnostic accuracies with AUCs of 0.990 (95% Confidence Interval [95%CI]: 0.983-0.996) and 0.978 (95%CI: 0.967-0.989), respectively. IgG assays outperformed IgA assays (p=0.01). Taking an assessed 15% inter-assay imprecision into account, an optimized IgG ratio cut-off > 2.5 displayed a 100% specificity (95%CI: 99-100) and a 100% positive predictive value (95%CI: 96-100). A 0.8 cut-off displayed a 94% sensitivity (95%CI: 88-97) and a 97% negative predictive value (95%CI: 95-99). Substituting the upper threshold for the manufacturer's, improved assay performance, leaving 8.9% of IgG ratios indeterminate between 0.8-2.5. CONCLUSIONS: The Euroimmun assay displays a nearly optimal diagnostic accuracy using IgG against SARS-CoV-2 in patient samples, with no obvious gains from IgA serology. The optimized cut-offs are fit for rule-in and rule-out purposes, allowing determination of whether individuals in our study population have been exposed to SARS-CoV-2 or not. IgG serology should however not be considered as a surrogate of protection at this stage.

Thirteen-year trends in the prevalence of diabetes in an urban region of Switzerland: a population-based study.

AIM: To assess trends in prevalence of total and diagnosed diabetes, and in the probability of detecting undiagnosed diabetes in the Swiss population. METHODS: The Bus Santé study is an annual cross-sectional study of adults residing in Geneva state, Switzerland. We included 8532 participants (51% women) from the years 2005 to 2017, when fasting plasma glucose data became available. Total diabetes was defined as the sum of diagnosed and undiagnosed diabetes, while diagnosed diabetes was defined as having a previous diagnosis, and undiagnosed diabetes as having fasting plasma glucose level of ≥7 mmol/l and no previous diagnosis. We calculated the probability of finding undiagnosed diabetes among participants without a diagnosis. We examined for linear and quadratic trends, grouping survey years into five survey periods. RESULTS: In total, 711 diabetes cases were identified over 13 years. The age- and gender-standardized prevalence of total diabetes decreased between the periods 2005-2009 and 2012-2013 from 9.6% (95% CI 8.3, 10.9) to 7.1% (95% CI 5.8, 8.4), but increased to 8.6% (95% CI 7.3%, 9.9%) by 2016-2017 (P-quadratic <0.01). For diagnosed diabetes, the prevalence decreased between 2005-2009 and 2014-2015 from 8.3% (95% CI 7.0%, 9.5%) to 6.1% (95% CI 5.0%, 7.2%), but increased slightly again to 7.0% (95% CI 5.8%, 8.2%) by 2016-2017 (P-quadratic = 0.01). Men generally had a higher prevalence of total and diagnosed diabetes than women, except in 2016-2017, when the prevalence of total diabetes was 9.5% (95% CI 7.6, 11.5) among men and 7.7% (95% CI 6.0, 9.5) among women (P >0.05). The probability of finding undetected diabetes among participants without a diabetes diagnosis decreased slightly between 2005-2009 and 2012-2013 from 1.5% (95% CI 0.9, 2.0) to 1.0% (95% CI 0.5, 1.5), but increased afterwards to 1.7% (95% CI 1.0, 2.3) by 2016-2017 (P-quadratic = 0.06); in 2016-2017, it was 2.6% (95% CI 1.5, 3.7) among men and 0.7% (95% CI 0.1, 1.3) among women (P <0.01). CONCLUSION: The prevalence of diabetes has remained relatively constant over time. However, the probability of finding undetected cases of diabetes in the population without diabetes may be increasing among men.