Socioeconomic status (SES) significantly influences mental health outcomes and treatment access, yet its reporting in psychedelic-assisted therapy trials remains underexplored. Here we systematically reviewed 98 articles (49 primary trials and 49 secondary analyses) published between 2006 and 2024 examining classic psychedelics and MDMA for mental health conditions. Only 12% of primary trials reported participant income data, and 31% reported educational attainment. In USA-based trials, participants showed markedly higher SES than the general population: 93% had some college education (versus 62% nationally), and median incomes in major trials substantially exceeded the national median for all workers. Non-US trials showed variable patterns. This widespread underreporting of SES data and evidence of socioeconomic disparities, particularly in US trials, highlights an urgent need for standardized SES reporting and targeted strategies to improve socioeconomic diversity in psychedelic-assisted therapy research, ensuring broader generalizability and access to these emerging treatments.

Progressive decline in episodic memory is a hallmark of Alzheimer's disease (AD). Emotional arousal is known to enhance memory. Enhanced encoding of emotionally arousing stimuli or events may improve memory in patients with AD; however, whether this effect is present in patients with AD remains unclear. Here we conducted a systematic search of the literature to identify relevant literature on emotional enhancement of memory in AD. Inclusion criteria were studies that (1) included individuals with Alzheimer's disease and (2) assessed emotional memory, particularly episodic memory. Thirty-five studies were included. Twelve out of 35 studies (34.3%) showed clear emotional enhancement of memory for episodic memory among participants with mild AD, while 13 studies (37.1%) found no effect. Ten studies (28.6%) found that emotional enhancement of memory was influenced by stimuli type, valence of emotion, level of encoding or intensity of emotion. Studies including brain imaging showed that amygdala and hippocampus volume are strong predictors of emotional enhancement of memory in AD, regardless of level of cognitive impairment. Evaluating volumes or networks of brain regions known to be involved in emotional memory processing may be a key factor influencing the preservation of enhanced encoding of emotional information. Future studies are needed to confirm whether atrophy of memory-related brain regions diminishes emotional enhancement of memory in AD.

Pain is a global health issue with substantial individual, societal and economic impacts. Given the risks of pharmacological treatments, complementary approaches to pain management are essential. Nature exposure has emerged as a promising nonpharmacological strategy, but evidence of its effectiveness is inconclusive. Here in this systematic review and meta-analysis we examined 62 studies (96 effects) across 21 countries, including 4,439 participants, to assess the impact of nature exposure on self-reported pain. The results indicate a significant small-to-moderate reduction in pain associated with nature exposure (standardized mean difference of 0.53), but studies exhibited moderate-to-high risk of bias and substantial heterogeneity. Studies evaluating nature against matched comparators reported effects roughly half the size of those using nonmatched controls and multisensory stimuli tended to show stronger effects. These findings support nature as a promising complementary pain management strategy. However, high heterogeneity and risk of bias warrant caution and highlight the need for more rigorous research.

Cognitive behavioral therapy has emerged as a promising intervention to enhance antiretroviral therapy adherence among people living with HIV. Here we conducted a systematic review and meta-analysis to evaluate the efficacy of cognitive behavioral therapy to improve antiretroviral therapy adherence, HIV viral load, viral suppression and CD4 counts. A total of 20 randomized controlled trials involving 1,739 people living with HIV were included, with most of the studies categorized as having low risk of bias. We show that cognitive behavioral therapy was associated with improved antiretroviral therapy adherence, with more pronounced effects for people living with HIV with psychiatric comorbidities and in studies conducted in low- and middle-income countries. No statistically significant findings were observed for HIV viral load, viral suppression or CD4 counts. These findings support the efficacy of cognitive behavioral therapy in enhancing antiretroviral therapy adherence, particularly for those with psychiatric comorbidities and in low- and middle-income countries. However, the impact of cognitive behavioral therapy on HIV viral load, viral suppression and CD4 counts remains inconclusive.

In this systematic review and meta-analysis, we assessed the efficacy of group arts interventions, where individuals engage together in a shared artistic experience (for example, dance or painting), for reducing depression and anxiety among older adults (> 55 yr without dementia). Fifty controlled studies were identified via electronic databases searched to February 2024 (randomised: 42, non-randomised: 8). Thirty-nine studies were included. Thirty-six studies investigated the impact of group arts interventions on depression (n = 3,360) and ten studies investigated anxiety (n = 949). Subgroup analyses assessed whether participant, contextual, intervention and study characteristics moderated the intervention-outcome relationship. Risk of bias was assessed with appropriate tools (RoB-2, ROBINS-1). Group arts interventions were associated with a moderate reduction in depression (Cohen's d = 0.70, 95% confidence interval (CI) = 0.54-0.87, P < 0.001) and a moderate reduction in anxiety (d = 0.76, 95% CI = 0.37-1.52, P < 0.001), although there was publication bias in the depression studies. After a trim and fill adjustment, the effect for depression remained (d = 0.42; CI = 0.35-0.50; P < 0.001). Context moderated this effect: There was a greater reduction in depression when group arts interventions were delivered in care homes (d = 1.07, 95% CI = 0.72-1.42, P < 0.001) relative to the community (d = 0.51, 95% CI = 0.32-0.70, P < 0.001). Findings indicate that group arts are an effective intervention for addressing depression and anxiety among older adults.

In recent years, the application of machine learning (ML) techniques in research on the prediction of post-traumatic stress disorder (PTSD) has increased. However, concerns regarding the clinical relevance and generalizability of ML findings hamper their implementation by clinicians and researchers. Here in this systematic review we examined (1) the extent to which pre-, peri- and post-traumatic risk factors identified using ML approaches coincide with the theoretical understanding of the disorder; (2) whether new insights were gained through ML techniques; and (3) whether ML findings, combined with previous research, enable an integrative model of PTSD risk encompassing both predictor categories and their theoretical relevance. We reviewed ML studies on PTSD risk factors in PubMed, Web of Science and Scopus. Studies were included if they specified when predictors and PTSD symptoms were collected in temporal relation to the traumatic event. A total of 30 studies with 12,908 participants (mean age 36.5 years) were included. After extracting the 15 most important predictors from all studies, we categorized them into pre-, peri- and post-trauma exposure predictors and examined their associations with established theoretical models of PTSD. Many studies exhibited a risk of bias, assessed using the prediction model risk of bias assessment tool (PROBAST). However, we found overlaps in identified predictors across studies, a concordance between data-driven results and theory-driven research, and underexplored predictors identified through ML. We propose an integrative model of PTSD risk that incorporates both data-driven and theory-driven findings and discuss future directions. We emphasize the importance of standards on how to apply and report ML approaches for mental health.

Pharmacogenomics could optimize antipsychotic treatment by preventing adverse drug reactions, improving treatment efficacy or relieving the cost burden on the healthcare system. Here we conducted a systematic review to investigate whether pharmacogenetic testing in individuals undergoing antipsychotic treatment influences clinical or economic outcomes. On 12 January 2024, we searched MEDLINE, EMBASE, PsycINFO and Cochrane Centrale Register of Controlled Trials. The results were summarized using a narrative approach and summary tables. In total, 13 studies were eligible for inclusion in the systematic review. The current evidence base is either in favor of pharmacogenetics-guided prescribing or showed no difference between pharmacogenetics and treatment as usual for clinical and economic outcomes. In the future, we require randomized controlled trials with sufficient sample sizes that provide recommendations for patients who take antipsychotics based on a broad, multigene panel, with consistent and comparable clinical outcomes.

The mental health effects of weather-related disasters are well characterized, yet less is known about the effect of chronic, slow-onset climate change. We systematically reviewed qualitative, quantitative and mixed-methods studies (57 were included) that investigated the effects of slow-onset climate change on a range of mental health indicators. Droughts, changing temperatures over time and local perceptions of ecosystem changes were the most studied slow-onset conditions. Several quantitative studies noted adverse mental health outcomes associated with these exposures, Including depression and anxiety symptoms, suicide and non-specific psychological distress. Qualitative studies further elucidated negative emotions related to chronic climate change, including worry, grief and frustration. However, some studies noted mixed or null findings. Results suggest a need for further research to identify causal pathways and mechanisms through which chronic changes in the climate may affect changes in mental health. Instead of focusing on trauma-based frameworks (as are commonly used in studies of acute disasters), this work should holistically consider individual, community and societal factors that shape the mental health consequences of slow-onset climate change.

Mindfulness-based programmes (MBPs) are widely used to prevent mental ill-health that is becoming the leading global cause of morbidity. Evidence suggests beneficial average effects but wide variability. We aimed to confirm the effect of MBPs on psychological distress, and to understand whether and how baseline distress, gender, age, education, and dispositional mindfulness modify the effect of MBPs on distress among adults in non-clinical settings.