Spatio-temporal trends and socio-environmental determinants of suicides in England (2002-2022): an ecological population-based study.

Background: Over the last two decades of suicide prevention strategy implementation, suicide rates in England have shown a fluctuating pattern, declining from the early 2000s (10.3 deaths per 100,000 in 2002) until around 2010 (9.0 deaths per 100,000 in 2007), then gradually increasing (10.7 deaths per 100,000 in 2022). It remains unclear whether the pattern varies by local area, the influence of the socio-environmental factors or a combination of both. Our aim was to evaluate spatio-temporal trends of suicides in England from 2002 to 2022 whilst examining the role of socio-environmental characteristics. Methods: In this ecological study, we analysed Office for National Statistics data on deaths by suicide, exploring spatial and temporal patterns in England (2002-2022). Using a Hurdle Poisson model fit within a Bayesian hierarchical framework, we assessed the effects of local area level deprivation, ethnic density, population density, light pollution, railway and road network densities and greenspace composition on suicide risk. Findings: From 2002 to 2022, suicide risk across England showed no substantial change overall (-4.26%; 95% Credible Interval (CrI): -8.95%, 0.72%). The difference between the regions with the lowest (London) and highest (North East) risk was 39.2% (95% CrI: 34.1%, 44.3%). We found that for one standard deviation change in each covariate, suicide risk increased with deprivation (20.06%; 95% CrI: 18.48%, 21.65%), railway network density (1.37%; 95% CrI: 0.32%, 2.46%), and road network density (5.16%; 95% CrI: 3.12%, 7.46%) while risk decreased with ethnic density (-7.47%; 95% CrI: -8.91%, -6.00%), population density (-5.42%; 95% CrI: -7.34%, -3.25%), light pollution (-4.20%; 95% CrI: -5.71%, -2.72%), and greenspace composition (-6.43%; 95% CrI: -7.94%, -4.99%). Interpretation: We did not find evidence to support a decline in suicide rates in England over the last 20 years and our findings highlight the community profiles, characterised by greater deprivation, isolation, and access to road/rail networks, where suicide risk was highest. This should help focus future research to understand these as drivers of suicide risk, leading to the development of effective area-level interventions and targeted investment in those approaches where most needed. Funding: Wellcome Trust, UKHSA, MRC, NIHR through its HPRU, HDRUK, NIHR University College Hospital London (UCLH) Biomedical Research Centre (BRC).