Spatial patterning and correlates of self-harm in Manchester, England.

Chien-Yu Lin,David Gunnell,Roger T Webb,Chia-Yueh Hsu,Caroline Clements,Shu-Sen Chang,Harriet Bickley,Nav Kapur

doi:10.1017/s2045796019000696

Abstract

To investigate the spatial distribution of self-harm incidence rates, their socioeconomic correlates and sex/age differences using data on self-harm presentations to emergency departments from The Manchester Self-Harm Project (2003-2013). Smoothed standardised incidence ratios for index self-harm episodes (n = 14 771) and their associations with area-level socioeconomic factors across 258 small areas (median population size = 1470) in the City of Manchester municipality were estimated using Bayesian hierarchical models. Higher numbers and rates of self-harm were found in the north, east and far southern zones of the city, in contrast to below average rates in the city centre and the inner city zone to the south of the centre. Males and females aged 10-24, 25-44 and 45-64 years showed similar geographical patterning of self-harm. In contrast, there was no clear pattern in the group aged 65 years and older. Fully adjusted analyses showed a positive association of self-harm rates with the percentage of the unemployed population, households privately renting, population with limiting long-term illness and lone-parent households, and a negative association with the percentage of ethnicity other than White British and travel distance to the nearest hospital emergency department. The area-level characteristics investigated explained a large proportion (four-fifths) of the variability in area self-harm rates. Most associations were restricted to those aged under 65 years and some associations (e.g. with unemployment) were present only in the youngest age group. The findings have implications for allocating prevention and intervention resources targeted at high-risk groups in high incidence areas. Targets for area-based interventions might include tackling the causes and consequences of joblessness, better treatment of long-term illness and consideration of the accessibility of health services.

Highlights

At least 800 000 people die by suicide worldwide every year; approximately 6000 of these deaths occur in the UK
In London, Canada, rates of self-harm were highest in the city centre and decreased as the distance from the centre increased (Jarvis et al, 1982); by contrast, in a recent study from London, England, self-harm rates were lower in areas closer to the city centre (Polling et al, 2019)
We considered the primary method of self-harm based on the likelihood of fatality and calculated standardised incidence ratios (SIRs) for selfharm by method

Summary

Introduction

At least 800 000 people die by suicide worldwide every year; approximately 6000 of these deaths occur in the UK. In London, Canada, rates of self-harm were highest in the city centre and decreased as the distance from the centre increased (Jarvis et al, 1982); by contrast, in a recent study from London, England, self-harm rates were lower in areas closer to the city centre (Polling et al, 2019). Another England-wide small-area analysis showed a non-linear association between a rurality indicator and rates of hospitalised self-harm episodes, with the highest rates occurring in suburban areas with intermediate rurality scores

Methods

Results

Discussion

Conclusion