Reward System in Late-Life Depression: a Cross-Sectional Case-Control Study.

OBJECTIVE: Anhedonia, commonly defined as a reduced ability to feel pleasure, is a core clinical symptom of late-life depression (LLD). Deficits in reward processing are hypothesised to be associated with anhedonia. We examined differences in reward sensitivity between patients with LLD and healthy controls and explored the associations between LLD-related symptomatology, global cognition, and the reward system. METHODS: The reward responsiveness of 63 patients with LLD and 58 healthy controls aged ≥60 years was assessed using the probabilistic reward learning task with an asymmetric reward schedule. RESULTS: Compared with healthy controls, patients with LLD displayed lower response bias and reward learning. Global cognition of all participants was positively correlated with response bias. In patients with LLD, anhedonia severity explained impaired reward learning. CONCLUSION: A deficit in reward processing is implicated in patients with LLD. Our findings suggest that executive dysfunction and anhedonia contribute to lower sensitivity to reward learning in patients with LLD.

Cognitive Stimulation for Persons with Dementia: a Systematic Review and Meta-Analysis.

OBJECTIVE: We aim to provide an up-to-date systematic review and meta-analysis of the effects of cognitive stimulation (CS) on cognition, depressive symptoms, and quality of life in persons with dementia. Factors affecting the treatment effect were examined. METHODS: A literature search was performed on databases of MEDLINE, EMBASE, PsycINFO, CINAHL Plus, and Cochrane Library up to 7 March 2019. Only randomised controlled trials investigating the effects of CS in persons with dementia were included. The outcome measures were cognitive function, depressive symptoms, and quality of life. RESULTS: 20 randomised controlled trials with a total of 1251 participants (intervention group: 674; control group: 577) were included for meta-analysis. Most participants had mild to moderate dementia. CS had a significant positive small-to-moderate effect on cognition (Hedges's g = 0.313, p < 0.001). Heterogeneity of CS was low to moderate (Q=30.5854, df=19, p < 0.05, I2 = 37.877%). Inconclusive results were found for depressive symptoms and quality of life. CONCLUSION: CS has a significant positive effect on cognitive function, but its effect on depressive symptoms and quality of life was inconclusive. Future studies with more robust methodology establishing evidence of its efficacy are required.

Suicidal Risk in Older Patients with Depression During COVID-19 Pandemic: a Case-Control Study.

OBJECTIVES: To compare older adults with late-life depression (LLD) and healthy controls in terms of suicidal ideation during the COVID-19 pandemic, and to determine predictors of suicidal ideation. METHODS: Between March and April 2020, old adults diagnosed with major depressive disorder (single or recurrent episode) as defined by the DSM-5 were recruited from psychiatric clinics or inpatient wards, whereas 31 healthy older adults without a history of depression or other psychiatric illnesses were recruited from voluntary organisations or elderly community centres. Their depressive symptoms, perceived severity of the pandemic, perceived time spent on receiving related information, perceived health, levels of loneliness, perceived coping efficacy, suicidal ideation, and the level of symptomatic responses to a specific traumatic stressor in the past week were assessed. RESULTS: In total, 21 men and 43 women aged 61 to 89 years were interviewed through telephone by trained research assistants. Of them, 33 were older adults with LLD (cases) and 31 were healthy older adults (controls). Older people with LLD had a higher level of suicidal ideation than healthy controls, after controlling for the level of depression and medical comorbidity (F (1, 59) = 5.72, p = 0.020). Regression analyses showed that coping efficacy and loneliness accounted for a significant portion of the variance in suicidal ideation, and loneliness significantly predicted the level of stress. Mediation analyses reveal an indirect effect between group and suicidal ideation through coping efficacy (Z = 2.43, p = 0.015). CONCLUSIONS: Older people with LLD are at increased suicidal risk and require timely mental health support. Coping efficacy and loneliness are important predictors for suicidal ideation and stress.

Mindfulness-Based Cognitive Therapy for Late-Life Depression: a Randomised Controlled Trial.

BACKGROUND: Rumination and overgeneral autobiographical memory are dysfunctional cognitions commonly found in older adults with depression. The theoretical underpinnings of mindfulness-based cognitive therapy (MBCT) address the ruminative tendencies and the non-specific retrieval of autobiographical memories. This study aims to examine the efficacy and cognitive mechanisms of MBCT in older adults with active depressive symptoms. METHODS: 57 older adults (mean age, 70 years) with normal cognition and mild to moderate depressive symptoms were randomly allocated to either the MBCT group or the active control group for 8 weeks. The MBCT group consisted of eight 2-hour weekly sessions and a 7-hour full-day retreat, with different themes for each class, guided mindfulness exercises, feedback and discussion, homework review, and psychoeducation. The active control group comprised a 1-hour physical exercise and a standardised health education of the specific theme with group discussion (eg fall prevention, chronic pain). Participants were assessed before and after the 8-week intervention for four outcome measures: the Hamilton Depression Rating Scale (HAMD), the Ruminative Response Scale (RRS), the Autobiographical Memory Test (AMT), and the Mindful Attention Awareness Scale (MAAS). RESULTS: There was a significant reduction in severity of depressive symptoms (HAMD score) in both the MBCT group (F(1, 27) = 35.9, p < 0.001, η2 = 0.57) and the active control group (F(1, 28) = 9.29, p < 0.01, η2 = 0.24), but only the MBCT group showed substantial improvements in autobiographical memory specificity (AMT score), rumination (RRS score), and mindfulness (MAAS score). CONCLUSION: Although both MBCT and active control programme decrease the severity of depressive symptoms in older adults, only MBCT improves AMS, rumination, and mindfulness. Our findings provide empirical support for the theoretical underpinnings of MBCT. Older adults with more severe depression and more severe dysfunctional cognition may benefit more from the specific therapeutic effects of MBCT.