The climate change emergency is also a mental healthcare emergency. We seek to provide a framework for what mental health professionals and organisations should do to make their practice more sustainable.

There are ethical, legal and organisational imperatives to make mental healthcare more sustainable. Mental healthcare must be refocused with an emphasis on prevention, building social capital and community resilience. Patients must be empowered to manage their own mental health. Efficiencies should be found within the system. Low-carbon ways to deliver care must be found, measured and improved upon. Greater adaptability needs to be built into the system to mitigate the impact of climate change. Sustainability should be integrated into training programmes, and good examples of practice shared and celebrated.

Mental health organisations and individuals must act now to prevent and adapt for the climate and ecological emergency. Sustainable practice is also good practice.

The prevalence of mental health conditions and national suicide rates are increasing in many countries. Lithium is widely and effectively used in pharmacological doses for the treatment and prevention of manic/depressive episodes, stabilising mood and reducing the risk of suicide. Since the 1990s, several ecological studies have tested the hypothesis that trace doses of naturally occurring lithium in drinking water may have a protective effect against suicide in the general population.

To synthesise the global evidence on the association between lithium levels in drinking water and suicide mortality rates.

The MEDLINE, Embase, Web of Science and PsycINFO databases were searched to identify eligible ecological studies published between 1 January 1946 and 10 September 2018. Standardised regression coefficients for total (i.e. both genders combined), male and female suicide mortality rates were extracted and pooled using random-effects meta-analysis. The study was registered with PROSPERO (CRD42016041375).

The literature search identified 415 articles; of these, 15 ecological studies were included in the synthesis. The random-effects meta-analysis showed a consistent protective (or inverse) association between lithium levels/concentration in publicly available drinking water and total (pooled β = −0.27, 95% CI −0.47 to −0.08; P = 0.006, I2 = 83.3%), male (pooled β = −0.26, 95% CI −0.56 to 0.03; P = 0.08, I2 = 91.9%) and female (pooled β = −0.13, 95% CI −0.24 to −0.02; P = 0.03, I2 = 28.5%) suicide mortality rates. A similar protective association was observed in the six studies included in the narrative synthesis, and subgroup meta-analyses based on the higher/lower suicide mortality rates and lithium levels/concentration.

This synthesis of ecological studies, which are subject to the ecological fallacy/bias, supports the hypothesis that there is a protective (or inverse) association between lithium intakes from public drinking water and suicide mortality at the population level. Naturally occurring lithium in drinking water may have the potential to reduce the risk of suicide and may possibly help in mood stabilisation, particularly in populations with relatively high suicide rates and geographical areas with a greater range of lithium concentration in the drinking water. All the available evidence suggests that randomised community trials of lithium supplementation of the water supply might be a means of testing the hypothesis, particularly in communities (or settings) with demonstrated high prevalence of mental health conditions, violent criminal behaviour, chronic substance misuse and risk of suicide.

Natural disasters are increasing in frequency and impact; they cause widespread disruption and adversity throughout the world. The Canterbury earthquakes of 2010–2011 were devastating for the people of Christchurch, New Zealand. It is important to understand the impact of this disaster on the mental health of children and adolescents.

To report psychiatric medication use for children and adolescents following the Canterbury earthquakes.

Dispensing data from community pharmacies for the medication classes antidepressants, antipsychotics, anxiolytics, sedatives/hypnotics and methylphenidate are routinely recorded in a national database. Longitudinal data are available for residents of the Canterbury District Health Board (DHB) and nationally. We compared dispensing data for children and adolescents residing in Canterbury DHB with national dispensing data to assess the impact of the Canterbury earthquakes on psychotropic prescribing for children and adolescents.

After longer-term trends and population adjustments are considered, a subtle adverse effect of the Canterbury earthquakes on dispensing of antidepressants was detected. However, the Canterbury earthquakes were not associated with higher dispensing rates for antipsychotics, anxiolytics, sedatives/hypnotics or methylphenidate.

Mental disorders or psychological distress of a sufficient severity to result in treatment of children and adolescents with psychiatric medication were not substantially affected by the Canterbury earthquakes.

Neighbourhood greenness or vegetative presence has been associated with indicators of health and well-being, but its relationship to depression in older adults has been less studied. Understanding the role of environmental factors in depression may inform and complement traditional depression interventions, including both prevention and treatment.

This study examines the relationship between neighbourhood greenness and depression diagnoses among older adults in Miami-Dade County, Florida, USA.

Analyses examined 249 405 beneficiaries enrolled in Medicare, a USA federal health insurance programme for older adults. Participants were 65 years and older, living in the same Miami location across 2 years (2010–2011). Multilevel analyses assessed the relationship between neighbourhood greenness, assessed by average block-level normalised difference vegetative index via satellite imagery, and depression diagnosis using USA Medicare claims data. Covariates were individual age, gender, race/ethnicity, number of comorbid health conditions and neighbourhood median household income.

Over 9% of beneficiaries had a depression diagnosis. Higher levels of greenness were associated with lower odds of depression, even after adjusting for demographics and health comorbidities. When compared with individuals residing in the lowest tertile of greenness, individuals from the middle tertile (medium greenness) had 8% lower odds of depression (odds ratio 0.92; 95% CI 0.88, 0.96; P = 0.0004) and those from the high tertile (high greenness) had 16% lower odds of depression (odds ratio 0.84; 95% CI 0.79, 0.88; P < 0.0001).

Higher levels of greenness may reduce depression odds among older adults. Increasing greenery – even to moderate levels – may enhance individual-level approaches to promoting wellness.

None.

Maternal exposure to major stressors during pregnancy has been found to increase the risk of neurodevelopmental, cognitive and psychiatric disorders in the offspring. However, the association between prenatal exposure to earthquake and the risk of adult schizophrenia has yet to be examined.

To explore the potential long-term effects of prenatal exposure to maternal stress on the risk of schizophrenia in adulthood, using the Great Tangshan Earthquake in 1976 as a natural experiment.

We obtained data from the Second China National Sample Survey on Disability, and analysed 94 410 Chinese individuals born between 1975 and 1979. We obtained difference-in-differences estimates of the earthquake effects on schizophrenia by exploiting temporal variation in the timing of earthquake exposure across four birth cohorts born between 1975 and 1979, along with geographical variation in earthquake severity at the prefecture level. Schizophrenia was ascertained by psychiatrists using the ICD-10 classification. Earthquake severity was measured by seismic intensity.

Earthquake cohort who experienced prenatal exposure to felt earthquake had higher risk of schizophrenia (odds ratio, 3.38; 95% CI 1.43–8.00) compared with the unexposed reference cohort. After specifying the timing of exposure by the trimester of pregnancy, prenatal exposure to felt earthquake during the first trimester of pregnancy increased the risk of adulthood schizophrenia significantly (odds ratio, 7.45; 95% CI 2.83–19.59).

Prenatal (particularly early pregnancy) exposure to maternal stress after a major disaster substantially affects the mental health of Chinese adults.

Studies on neighbourhood characteristics and depression show equivocal results.

This large-scale pooled analysis examines whether urbanisation, socioeconomic, physical and social neighbourhood characteristics are associated with the prevalence and severity of depression.

Cross-sectional design including data are from eight Dutch cohort studies (n= 32 487). Prevalence of depression, either DSM-IV diagnosis of depressive disorder or scoring for moderately severe depression on symptom scales, and continuous depression severity scores were analysed. Neighbourhood characteristics were linked using postal codes and included (a) urbanisation grade, (b) socioeconomic characteristics: socioeconomic status, home value, social security beneficiaries and non-Dutch ancestry, (c) physical characteristics: air pollution, traffic noise and availability of green space and water, and (d) social characteristics: social cohesion and safety. Multilevel regression analyses were adjusted for the individual's age, gender, educational level and income. Cohort-specific estimates were pooled using random-effects analysis.

The pooled analysis showed that higher urbanisation grade (odds ratio (OR) = 1.05, 95% CI 1.01–1.10), lower socioeconomic status (OR = 0.90, 95% CI 0.87–0.95), higher number of social security beneficiaries (OR = 1.12, 95% CI 1.06–1.19), higher percentage of non-Dutch residents (OR = 1.08, 95% CI 1.02–1.14), higher levels of air pollution (OR = 1.07, 95% CI 1.01–1.12), less green space (OR = 0.94, 95% CI 0.88–0.99) and less social safety (OR = 0.92, 95% CI 0.88–0.97) were associated with higher prevalence of depression. All four socioeconomic neighbourhood characteristics and social safety were also consistently associated with continuous depression severity scores.

This large-scale pooled analysis across eight Dutch cohort studies shows that urbanisation and various socioeconomic, physical and social neighbourhood characteristics are associated with depression, indicating that a wide range of environmental aspects may relate to poor mental health.

None.

Natural disasters are increasing in frequency and severity. They cause widespread hardship and are associated with detrimental effects on mental health.

Our aim is to provide the best estimate of the effects of natural disasters on mental health through a systematic review and meta-analysis of the rates of psychological distress and psychiatric disorder after natural disasters.

This systematic review and meta-analysis is limited to studies that met predetermined quality criteria. We required included studies to make comparisons with pre-disaster or non-disaster exposed controls, and sample representative populations. Key studies were identified through a comprehensive search of PubMed, EMBASE and PsycINFO from 1980 to 3 March 2017. Random effects meta-analyses were performed for studies that reported key outcomes with appropriate statistics.

Forty-one studies were identified by the literature search, of which 27 contributed to the meta-analyses. Continuous measures of psychological distress were increased after natural disasters (combined standardised mean difference 0.63, 95% CI 0.27–0.98, P = 0.005). Psychiatric disorders were also increased (combined odds ratio 1.84, 95% CI 1.43–2.38, P < 0.001). Rates of post-traumatic stress disorder and depression were significantly increased after disasters. Findings for anxiety and alcohol misuse/dependence were not significant. High rates of heterogeneity suggest that disaster-specific factors and, to a lesser degree, methodological factors contribute to the variance between studies.

Increased rates of psychological distress and psychiatric disorders follow natural disasters. High levels of heterogeneity between studies suggest that disaster variables and post-disaster response have the potential to mitigate adverse effects.

None.

None.

Stress-related illnesses are a major threat to public health, and there is increasing demand for validated treatments.

To test the efficacy of nature-based therapy (NBT) for patients with stress-related illnesses.

Randomised controlled trial (ClinicalTrials.gov ID NCT01849718) comparing Nacadia® NBT (NNBT) with the cognitive–behavioural therapy known as Specialised Treatment for Severe Bodily Distress Syndromes (STreSS). In total, 84 participants were randomly allocated to one of the two treatments. The primary outcome measure was the mean aggregate score on the Psychological General Well-Being Index (PGWBI).

Both treatments resulted in a significant increase in the PGWBI (primary outcome) and a decrease in burnout (the Shirom–Melamed Burnout Questionnaire, secondary outcome), which were both sustained 12 months later. No significant difference in efficacy was found between NNBT and STreSS for primary outcome and secondary outcomes.

The study showed no statistical evidence of a difference between NNBT and STreSS for treating patients with stress-related illnesses.

None.

Previous studies revealed a relationship between residential green space availability and health, especially mental health. Studies on blue space are scarcer and results less conclusive.

To investigate the hypotheses that green and blue space availability are negatively associated with anxiety and mood disorders, and positively associated with self-reported mental and general health.

Health data were derived from a nationally representative survey (NEMESIS-2, n=6621), using a diagnostic interview to assess disorders. Green and blue space availability were expressed as percentages of the area within 1 km from one's home.

The hypotheses were confirmed, except for green space and mood disorders. Associations were generally stronger for blue space than for green space, with ORs up to 0.74 for a 10%-point increase.

Despite the different survey design and health measures, the results largely replicate those of previous studies on green space. Blue space availability deserves more systematic attention.