The Effect of Clozapine on Self-reported Duration of Sleep and Its Interaction With 23 Other Medications: A 5-Year Naturalistic Study.

BACKGROUND: Sedation is a common and incapacitating clozapine adverse effect, but the factors associated with sedation and its pharmacological management remain poorly studied. METHODS: We conducted a retrospective cohort study based on deidentified electronic clinical records of clozapine-treated patients from the secondary mental health care provider for Cambridgeshire and Peterborough, United Kingdom. We first evaluated cross-sectionally the influence of clozapine dose, clozapine, and norclozapine plasma levels on self-reported hours slept, as a proxy for sedation, using bivariate correlation and then the longitudinal effect of changes in clozapine dose and other 23 medications using linear mixed effect models. We followed 241 clozapine-treated patients for 56 months on average, with 2237 face-to-face assessments in total. RESULTS: Patients slept for a mean of 9.35 h/d, with 46% reporting 10 h/d or more. Cross-sectionally, sleep duration did not correlate with clozapine dose (r = 0.14, P = 0.106), but with clozapine plasma levels (r = 0.38, P < 0.0001) and norclozapine plasma levels (r = 0.25, P = 0.005). Longitudinally, the final mixed-effects model revealed 4 pharmacological variables that had a significant impact on hours slept: clozapine, risperidone augmentation, and atenolol were associated with increased sleep, whereas aripiprazole augmentation was associated with decreased sleep. We found that 20 other psychotropic medications measured were not associated with changes in sleep when added to clozapine. Excess sleep is a clozapine level-dependent adverse effect. CONCLUSIONS: The impact of different augmentation strategies might help clinicians decide on the most adequate strategy, albeit further studies should confirm our results.

Memory encoding and dopamine in the aging brain: a psychopharmacological neuroimaging study.

Normal aging brings with it changes in dopaminergic and memory functions. However, little is known about how these 2 changes are related. In this study, we identify a link between dopamine, episodic memory networks, and aging, using pharmacological functional magnetic resonance imaging. Young and older adults received a D2-like agonist (Bromocriptine, 1.25 mg), a D2-like antagonist (Sulpiride, 400 mg), and Placebo, in a double-blind crossover procedure. We observed group differences, during memory encoding, in medial temporal, frontal, and striatal regions and moreover, these regions were differentially sensitive across groups to dopaminergic perturbation. These findings suggest that brain systems underlying memory show age-related changes and that dopaminergic function may be key in understanding these changes. That these changes have behavioral consequences was suggested by the observation that drug modulations were most pronounced in older subjects with poorer recognition memory. Our findings provide direct evidence linking ageing, memory, and dopaminergic change.

Factors in Psychiatric Admissions: Before and During the Covid-19 Pandemic.

OBJECTIVE: The COVID-19 pandemic has impacted community mental health, but the effect on psychiatric admissions is unknown. We investigated factors contributing to acute psychiatric admissions, and whether this changed during the first UK lockdown. METHOD: A retrospective case-note review study with an exploratory mixed-methods design to examine factors for psychiatric admissions following the first UK 2020 lockdown compared to the same time periods in 2019 and 2018. RESULTS: Themes of psychopathology, risk, social stressors, community treatment issues, and physical health concerns were generated. The mean number of codes per case was 6.19 (s . d. = 2.43), with a mean number of categories per case of 3.73, (s. d. = 0.98). Changes in routines and isolation were common factors in the study year; accommodation and substance abuse were more prominent in the control year. Relationship stressors featured strongly in both groups. There were significantly more women (χ2(1, N = 98) = 20.80, p < 0.00001) and older adults (χ2(1, N = 98) = 8.61, p = 0.0033) in the study group than the control. Single people, compared to those in a relationship (χ2(1, N = 45) = 4.46, p = 0.035), and people with affective disorders compared to psychotic disorders ((χ2(1, N = 28) = 5.19, p = 0.023), were more likely to have a COVID-19 related admission factor. CONCLUSIONS: Early stages of the COVID-19 pandemic amplified pre-existing psychosocial vulnerabilities with a disproportionate psychiatric admissions impact on the mental health of women, older adults and those with affective disorders.