Table 2 Factors associated with overdose categorised by theme
Theme | Referent | Factor | Paper | Estimate | Adjusted estimate |
|---|---|---|---|---|---|
Income | No | Sex work (last six months) | Fairbairn | OR: 2.1 (1.0-4.3) | … |
No | Sold Drugs (past 30 days). | Latkin (2019) | OD < 1 year ago: OR: 2.7 (1.1–6.6) | … | |
< 10 years | > 10 years sex work, ever OD. | El-Bassel | … | aOR: 2.5 (1.5–4.3) | |
< 10 years | > 10 years sex work, recent Intimate partner violence, recent OD. | El-Bassel | … | aOR: 4.1 (1.4–11.8) | |
< 10 years | > 10 years sex work, recent non partner violence, recent OD. | El-Bassel | … | aOR: 4.0 (1.4–11.6) | |
No | Unemployed 6 + months prior to prison | Winter | RR: 5.4 (2.2–12.9) | aRR: 4.4 (1.9–10.4) | |
No | Welfare receipt (males only). | Pabayo | … | aOR: 1.4 (1.1-2.0) | |
No | Welfare receipt (females only). | Pabayo | … | aOR: 1.7 (1.2–2.4) | |
Middle/upper class | Lower social class growing up. | Silva | OR: 1.8 (1.3–2.7) | aOR: 1.8 (1.2–2.8) | |
No | Sex work (last six months) | Harris | OR: 1.6 (1.3-2.0) | … | |
No | Unemployed. | Mitra | OR: 4.3 (2.7-7.0) | … | |
Homeless/ housing instability | No | Past 90-day homelessness. | Silva | OR: 2.7 (1.7–4.1) | … |
No | Homeless last six months (males only). | Pabayo | … | aOR: 1.3 (1.0-1.6) | |
No | Current homelessness. | Riggs | … | aOR: 1.3 (1.0-1.7) | |
No | Ever homeless. | Thumath | OR: 4.9 (2.3–10.5) | … | |
No | Recent homeless (last six months). | Thumath | OR: 1.6 (1.1–2.3) | … | |
No | Unstable accommodation in month prior to imprisonment. | Winter | RR: 2.8 (1.0-7.4) | … | |
No | Ever lived in foster home. | Silva | OR: 1.6 (1.0-2.3) | … | |
No | Unhoused last six months. | Harris | OR: 1.7 (1.4–2.1) | … | |
No | Unhoused last six months (sex workers only). | Harris | OR: 1.5 (1.1–2.1) | … | |
No | Housing insecurity. | Mitra | OR: 7.5 (3.6–13.8) | … | |
No | Recent homelessness (last six months). | Tomko | OR: 2.1 (1.5–2.9) | aOR: 1.9 (1.3–2.7) | |
Incarceration | No | Incarceration (past 6 months). | Lake | OR: 2.2 (1.5–3.3) | With physical neglect: aOR: 2.3 (1.8–2.8) With emotional neglect: aOR: 1.9 (1.5–2.4) |
No | Ever incarcerated. | Milloy | OR: 4.4 (1.8–10.8) | aOR: 3.8 (1.5–9.7) | |
N/A | Having recently been released from drug treatment or incarceration. | Lamonica | QS (increased risk) | QS (increased risk) | |
No | History of incarceration. | El-Bassel | … | aOR: 4.3 (2.6–7.3) | |
No | History of incarceration with recent intimate partner violence. | El-Bassel | … | aOR: 4.7 (1.8-12.48) | |
No | History of incarceration with recent non partner violence. | El-Bassel | … | aOR: 3.68 (1.4–9.5) | |
No | History of previous adult incarceration. | Winter | RR: 4.9 (1.4–16.8) | … | |
No | Ever incarcerated. | Silva | OR: 2.2 (1.4–3.5) | … | |
No | Serious mental illness (among recently liberated) | Pizzicato | … | aHR 1.5 (1.3–1.9) | |
No | Incarceration (last six months). | Harris | OR: 1.9 (1.5–2.6) | … | |
Traumatic experiences | N/A | Emotional trauma (negative life events, states of depression) | Lamonica | QS (increased risk) | QS (increased risk) |
No | Food insecurity (last six months) | Thumath | OR: 1.9 (1.3–2.8) | … | |
No | Child removed (ever). | Thumath | OR: 1.8 (1.2–2.7) | aOR: 1.6 (1.0-2.4) | |
N/A | Child custody loss. | Lamonica | QS (increased risk) | QS (increased risk) | |
No | Removed from family as a child. | Winter | RR: 5.8 (2.4–13.9) | aRR: 4.4 (1.8–10.9) | |
No | Removal from parental care. | Thumath | OR: 2.3 (1.5–3.4) | … | |
None/low | Moderate/severe emotional abuse. | Lake | … | aOR: 1.5 (1.2–1.9) | |
No | Intimate Partner Violence (last six months). | Thumath | OR: 2.2 (1.2–3.9) | … | |
No | Severe physical violence (ever). | El-Bassel | OR: 1.6 (1.1–1.6) | aOR: 1.3 (1.0-1.6) | |
No | Multiple types of violence (ever). | El-Bassel | OR: 1.8 (1.4–2.3) | … | |
No | Recent severe physical violence recent coupled with recent intimate partner violence. | El-Bassel | OR: 1.4 (1.00-1.9) | … | |
No | Multiple types of recent violence coupled with recent intimate partner violence. | El-Bassel | OR: 1.5 (1.00-2.1) | … | |
No | Recent severe physical violence coupled with recent non- partner violence. | El-Bassel | OR: 1.4 (1.1–1.7) | aOR: 1.3 (1.0-1.7) | |
No | Multiple types of recent violence coupled with recent non- partner violence. | El-Bassel | OR: 1.7 (1.2–2.5) | … | |
None/low | Moderate/severe physical abuse. | Lake | OR: 1.5 (1.0-2.2) | aOR: 1.4 (1.1–1.7) | |
None/low | Moderate/severe sexual abuse. | Lake | OR: 1.6 (1.1–2.3) | aOR: 1.5 (1.2–1.9) | |
None/low | Moderate/severe physical neglect. | Lake | … | aOR: 1.3 (1.0-1.6) | |
No | Physical and/or sexual workplace violence (last six months). | Goldenberg | OR: 2.1 (1.5–2.9) | … | |
|  | Any physical/sexual violence. | Argento | HR: 1.9 (1.1–3.2) | … | |
No | Violence last six months. | Harris | OR: 1.8 (1.5–2.2) | … | |
No | Violence last six months (sex workers only). | Harris | OR: 2.2 (1.6–2.9) | aOR: 2.6 (1.9–3.5) | |
Never | Daily psychological pain. | Tomko | OR: 2.4 (1.7–3.3) | aOR: 1.7 (1.1–2.5) | |
Overdose risk perception and past experience | Five-point scale | Overdose perceived severity (increasing). | Bonar | IRR: 0.6 (0.4–0.8) | … |
Five-point scale | Overdose perceived susceptibility (increasing). | Bonar | IRR: 1.5 (1.0-2.8) | … | |
N/A | Low understanding of overdose risk (novice to drug use, polydrug use). | Lamonica | QS (increased risk) | QS (increased risk) | |
Increasing number | Previous overdose. | Grau | … | aRR: 1.7 (1.1–2.6) | |
No | Witnessed overdose. | Riggs | … | aOR: 2.0 (1.6–2.4) | |
Increasing number | Number of times seen others overdose. | Schiavon | … | aOR: 1.4 (1.1–1.8) | |
Increasing number | Past friend overdose. | Schiavon | … | aOR: 4.21 (2.0-8.9) | |
No | Ever witnessed family member overdose. | Silva | OR: 2.1 (1.4–3.1) | aOR: 1.6 (1.0-2.5) | |
Healthcare experiences | No | Unmet need for health services (last six months). | Goldenberg | OR: 1.7 (1.2–2.3) | … |
No | Ever in addictions treatment. | Havens | IRR: 2.1 (1.3–3.4) | aIRR: 1.6 (1.0-2.5) | |
No | Denied access to addictions treatment (past 6 months). | Lake | OR: 2.5 (1.4–4.6) | … | |
No addictions treatment | Any addictions treatment. | Latkin (2019) | OD > 1 year ago: OR: 1.5 (1.1-2.0) | … | |
No | Ever on opioid substitution treatment. | Winter | … | aRR: 3.0 (1.2–7.6) | |
No | Ever in addictions treatment. | Silva | OR: 2.4 (1.7–3.6) | … | |
Increasing number | Number of treatment episodes at buprenorphine clinic. | Schiavon | … | aOR: 1.6 (1.2–2.1) | |
No | Unmet mental health need. | Tomko | OR: 1.9 (1.4–2.4) | aOR: 1.4 (1.0-1.9) | |
Perception of own drug use and injecting skill | No | Self-reported drug problem (last 12 months) | Riggs | … | aOR: 5.1 (4.1–6.4) |
N/A | Lack of knowledge or control (drug quality) of tolerance. | Lamonica | QS (increased risk) | QS (increased risk) | |
N/A | Sense of ‘opioid expertise’ (experience, knowledge, tolerance, and self-control regarding opioids) | Chang | QS (increased risk) | QS (increased risk) | |
No | Required help injecting (past 6 months). | Lake | OR: 1.9 (1.3–2.7) | With physical abuse: aOR: 1.7 (1.4–2.1) With sexual abuse: aOR: 1.7 (1.4–2.1) With physical neglect: aOR: 1.7 (1.4–2.1) With emotional neglect: aOR: 1.5 (1.2–1.9) | |
No | Required help injecting (males only). | Pabayo | … | aOR: 1.74 (1.1–1.8) | |
Injecting setting | No | Injecting alone (last six months). | Lake | OR: 1.8 (1.1–2.9) | … |
No injecting alone. | Injecting alone (last six months). | Fairbairn | OR: 0.4 (0.2–0.8) | … | |
No public injecting. | Public injecting (last six months). | Fairbairn | OR: 4.7 (2.4–9.4) | … | |
No | Rushed injection from fear of police (last six months) | Bazazi | OR: 2.0 (1.3–3.3) | aOR: 1.9 (1.1–3.6) | |
No | Rushed outdoor drug use (last six months) | Goldenberg | OR: 1.3 (1.0-1.6) | … | |
No | Injecting in public (last six months). | Lake | OR: 2.8 (1.9–4.1) | With emotional abuse: aOR: 1.9 (1.6–2.4) With emotional neglect: aOR: 1.7 (1.3–2.1) | |
Conditions within physical environment | No | Police-related barriers to harm reduction (last six months). | Goldenberg | OR: 1.7 (1.3–2.2) | aOR: 2.2 (1.6–2.9) |
No | Needle exchange main source of injecting equipment (last six months). | Bazazi | OR: 0.4 (0.2–0.6) | … | |
No | Replaced syringes through exchange service (last six months). | Latkin (2019) | OD < 1 year ago: OR: 3.7 (1.8–8.1) OD > 1 year ago: OR: 3.3 (2.1–5.2) | … | |
Area with less coverage | Resident in area with high harm reduction coverage. | Vallance | OR: 2.2 (1.4–3.4) | aOR: 2.2 (1.3–3.8) | |
Fewer settings | Number of drug use settings (per additional setting) [last six months] | Latkin (2019) | OD < 1 year ago: OR: 1.5 (1.2–1.8) OD > 1 year ago: OR: 1.3 (1.1–1.6) | OD < 1 year ago: aOR: 1.3 (1.0-1.7) OD > 1 year ago: aOR: 1.3 (1.1–1.6) | |
No | Police-related barriers to harm reduction (last six months) | Argento | HR 3.0 (1.8–4.9) | aHR 2.6 (1.5–4.5) | |
No | Stopped, searched, detained, or assaulted by the police. | Harris | OR: 1.5 (1.1–2.2) | … | |
No | Lives in area characterized by prevalent drug use, marginalization, and criminalization. | Harris | OR: 1.4 (1.1–1.7) | … | |
No | Stopped, searched, detained, or assaulted by the police (sex workers only). | Harris | OR: 1.6 (1.1–2.3) | aOR: 2.0 (1.3-3.0) | |
Social network traits | Increasing number | Number of support members in social network. | Havens | IRR: 1.3 (1.1–1.6) | aIRR: 1.2 (1.0-1.4) |
None | Three or more social supports (females only). | Pabayo | … | aOR: 0.5 (0.3–0.9) | |
Increasing number | Density of social network at visit 1. | Tobin | … | aOR: 0.1 (0.0-0.4) | |
Increasing number | Change in density of social network over study. | Tobin | … | aOR: 0.2 (0.1–0.5) | |
Increasing number | Density of social network at visit 1 (recent injectors). | Tobin | … | aOR: 0.1 (0.0-0.5) | |
Increasing number | Change in density of social network over study (recent injectors). | Tobin | … | aOR: 1.2 (1.1–1.4) | |
Increasing number | Number of social network members participant had conflict with. | Latkin (2004) | OR: 1.3 (1.1–1.5) | … | |
N/A | Being with friends/partners that use drugs. | Lamonica | QS (increased risk) | QS (increased risk) | |
No | Provide drugs for intimate male partner (last six months). | Goldenberg | OR: 1.4 (1.0-1.9) | … | |
Increasing number | Number of injectors in social network over study (recent injectors only). | Tobin | … | aOR: 0.2 (0.1–0.5) | |
Increasing number | Number in social network who snort heroin. | Latkin (2004) | OR: 0.8 (0.7–0.9) | … | |
Increasing number | Number in social network who inject heroin (past overdose). | Latkin (2004) | OR: 1.2 (1.0-1.4) | … | |
Increasing number | Number in social network who inject heroin (recent overdose). | Latkin (2004) | OR: 1.3 (1.0-1.5) | … |