The long-term effects of consecutive COVID-19 waves on mental health.

BACKGROUND: Although several studies have documented the impact of the COVID-19 pandemic on mental health, the long-term effects remain unclear. AIMS: To examine longitudinal changes in mental health before and during the consecutive COVID-19 waves in a well-established probability sample. METHOD: An online survey was completed by the participants of the COVID-19 add-on study at four time points: pre-COVID-19 period (2014-2015, n = 1823), first COVID-19 wave (April to May 2020, n = 788), second COVID-19 wave (August to October 2020, n = 532) and third COVID-19 wave (March to April 2021, n = 383). Data were collected via a set of validated instruments, and analysed with latent growth models. RESULTS: During the pandemic, we observed a significant increase in stress levels (standardised ß = 0.473, P < 0.001) and depressive symptoms (standardised ß = 1.284, P < 0.001). The rate of increase in depressive symptoms (std. covariance = 0.784, P = 0.014), but not in stress levels (std. covariance = 0.057, P = 0.743), was associated with the pre-pandemic mental health status of the participants. Further analysis showed that secondary stressors played a predominant role in the increase in mental health difficulties. The main secondary stressors were loneliness, negative emotionality associated with the perception of COVID-19 disease, lack of resilience, female gender and younger age. CONCLUSIONS: The surge in stress levels and depressive symptoms persisted across all three consecutive COVID-19 waves. This persistence is attributable to the effects of secondary stressors, and particularly to the status of mental health before the COVID-19 pandemic. Our findings reveal mechanisms underlying the surge in mental health difficulties during the COVID-19 waves, with direct implications for strategies promoting mental health during pandemics.

Risk Factors Underlying COVID-19 Lockdown-Induced Mental Distress.

Recent reports suggest that the COVID-19 lockdown resulted in changes in mental health, however, potential age-related changes and risk factors remain unknown. We measured COVID-19 lockdown-induced stress levels and the severity of depressive symptoms prior to and during the COVID-19 lockdown in different age groups and then searched for potential risk factors in a well-characterized general population-based sample. A total of 715 participants were tested for mental distress and related risk factors at two time-points, baseline testing prior to COVID-19 and follow-up testing during COVID-19, using a battery of validated psychological tests including the Perceived Stress Scale and the Patient Health Questionnaire. Longitudinal measurements revealed that the prevalence of moderate to high stress and the severity of depressive symptoms increased 1.4- and 5.5-fold, respectively, during the COVID-19 lockdown. This surge in mental distress was more severe in women, but was present in all age groups with the older age group exhibiting, cross-sectionally, the lowest levels of mental distress prior to and during the lockdown. Illness perception, personality characteristics such as a feeling of loneliness, and several lifestyle components were found to be associated with a significant increase in mental distress. The observed changes in mental health and the identified potential risk factors underlying these changes provide critical data justifying timely and public emergency-tailored preventive, diagnostic, and therapeutic mental health interventions, which should be integrated into future public health policies globally.

Cingulate cortex in pre-MCI cognition.

Studies of Alzheimer's disease over the years have focused on the prodromal stage, or mild cognitive impairment (MCI), in order to understand its evolution and to diagnose this pathology early. More recently, research has focused on an even earlier stage (pre-MCI) characterized in particular by a cognitive complaint. The purpose of this chapter is, first, to describe the different concepts defining pre-MCI, which refers to cognitive or memory complaint, and to define this concept based on biologic markers (abnormal proteins and neuroimaging). In the second part of the chapter, we describe the cognitive performance of these subjects (pre-MCI), and, finally, in the third part we describe the correlations linking cognitive performance of pre-MCI subjects to cingulate cortex, cingulate gyrus, and cingulum bundle.

[Subjective cognitive impairment and Alzheimer's disease: a two year follow up of 51 subjects during two years]. / Subjective cognitive impairment et maladie d'Alzheimer : étude d'une cohorte de 51 sujets suivis sur deux ans.

Subjective cognitive impairment (SCI) is defined by a state of subjective complaint, without objective cognitive deterioration. Amnestic mild cognitive impairment (A-MCI), which characterizes a syndrome between normal cognitive aging and early Alzheimer's disease (E-AD), is preceded by A-MCI from many years. SCI expresses a metacognitive impairment. A cohort of 51 subjects [7 normal controls (NC), 28 SCI, 12 A-MCI and 5 E-AD] was followed up during 24 months, with a neuropsychological evaluation each 6 months during 1 year (V1, V2, V3), then 1 year later (V4). Among the 28 SCI, 6 converted to A-MCI at V4 (21.42%), 1 to A-MCI-A at V3, then to E-AD at V4. These results suggest a continuum from SCI to A-MCI, and E-AD. Progressive SCI differed from non-progressive SCI on verbal episodic memory and executive functions tests at the initial examination. MRI showed anterior cingular atrophy in all SCI patients but hippocampal atrophy was only observed in 20 patients. Our results suggest that metacognition impairment is the expression of a dysfunction in the anterior pre-frontal cortex, in correlation with a syndrome of hyper-attention.