Loneliness during the Covid-19 pandemic in Germany: Impact of social factors and polygenic risk scores on interpersonal differences in loneliness and mental health.

OBJECTIVES: The outbreak of Covid-19 negatively affected mental health and increased loneliness. The subjective feeling of loneliness is influenced by genetic and social factors and has a negative impact on mental health. METHODS: From March 2020 to June 2021 loneliness was investigated in N = 517 individuals using monthly acquired questionnaire data and Latent Growth Curve Analysis. Associations of social factors and polygenic risk scores (PRSs, n = 361) with class membership were investigated. RESULTS: Three classes ("average", 40%; "not lonely", 38%; "elevated loneliness", 22%) were identified, that differ significantly regarding loneliness, mental dysfunction, and response to the lockdown phases. Individuals with a high PRS for neuroticism are more likely to belong to the "elevated loneliness" class, living with another person is a protective factor. CONCLUSION: As the "elevated loneliness" class was at the highest risk of mental dysfunction, our findings underscore the importance of identifying those individuals to implement counteractive measures.

Preliminary Findings Associate Hippocampal 1H-MR Spectroscopic Metabolite Concentrations with Psychotic and Manic Symptoms in Patients with Schizophrenia.

BACKGROUND AND PURPOSE: Previous hippocampal proton MR spectroscopic imaging distinguished patients with schizophrenia from controls by elevated Cr levels and significantly more variable NAA and Cho concentrations. This goal of this study was to ascertain whether this metabolic variability is associated with clinical features of the syndrome, possibly reflecting heterogeneous hippocampal pathologies and perhaps variability in its "positive" (psychotic) and "negative" (social and emotional deficits) symptoms. MATERIALS AND METHODS: In a sample of 15 patients with schizophrenia according to the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, we examined the association of NAA and Cho levels with research diagnostic interviews and clinical symptom ratings of the patients. Metabolite concentrations were previously obtained with 3D proton MR spectroscopic imaging at 3T, a technique that facilitates complete coverage of this small, irregularly shaped, bilateral, temporal lobe structure. RESULTS: The patient cohort comprised 8 men and 7 women (mean age, 39.1 [SD, 10.8] years, with a mean disease duration of 17.2 [SD, 10.8] years. Despite the relatively modest cohort size, we found the following: 1) Elevated Cho levels predict the positive (psychotic, r = 0.590, P = .021) and manic (r = 0.686, P = .005) symptom severity; and 2) lower NAA levels trend toward negative symptoms (r = 0.484, P = .08). No clinical symptoms were associated with Cr level or hippocampal volume (all, P ≥ .055). CONCLUSIONS: These preliminary findings suggest that NAA and Cho variations reflect different pathophysiologic processes, consistent with microgliosis/astrogliosis and/or lower vitality (reduced NAA) and demyelination (elevated Cho). In particular, the active state-related symptoms, including psychosis and mania, were associated with demyelination. Consequently, their deviations from the means of healthy controls may be a marker that may benefit precision medicine in selection and monitoring of schizophrenia treatment.