Personalized risk assessment of drug-related harm is associated with health outcomes.
BACKGROUND
The Independent Scientific Committee on Drugs (ISCD) assigned quantitative scores for harm to 20 drugs. We hypothesized that a personalized, ISCD-based Composite Harm Score (CHS) would be associated with poor health outcomes in polysubstance users.


METHODS
A prospective community sample (n=293) of adults living in marginal housing was assessed for substance use. The CHS was calculated based on the ISCD index, and the personal substance use characteristics over four weeks. Regression models estimated the association between CHS and physical, psychological, and social health outcomes.


RESULTS
Polysubstance use was pervasive (95.8%), as was multimorbid illness (median 3, possible range 0-12). The median CHS was 2845 (interquartile range 1865-3977). Adjusting for age and sex, every 1000-unit CHS increase was associated with greater mortality (odds ratio [OR] 1.47, 95% confidence interval [CI] 1.07-2.01, p = 0.02), and persistent hepatitis C infection (OR 1.29, 95% CI 1.02-1.67, p = 0.04). The likelihood of substance-induced psychosis increased 1.39-fold (95% CI 1.13-1.67, p = 0.001). The amount spent on drugs increased 1.51-fold (1.40-1.62, p < 0.001) and the odds of having committed a crime increased 1.74-fold (1.46-2.10, p < 0.001). Multimorbid illness increased 1.43-fold (95% CI 1.26-1.63, p < 0.001).


CONCLUSIONS
Greater CHS predicts poorer physical, psychological, and social health, and may be a useful quantitative, personalized measure of risk for drug-related harm.
Department of Psychiatry, University of British Columbia, Vancouver, Canada.
Andrea A
AA
Jones
Fidel
F
Vila-Rodriguez
William J
WJ
Panenka
Olga
O
Leonova
Verena
V
Strehlau
Donna J
DJ
Lang
Allen E
AE
Thornton
Hubert
H
Wong
Alasdair M
AM
Barr
Ric M
RM
Procyshyn
Geoffrey N
GN
Smith
Tari
T
Buchanan
Mel
M
Krajden
Michael
M
Krausz
Julio S
JS
Montaner
G William
GW
Macewan
David J
DJ
Nutt
William G
WG
Honer
D000328:Adult; D005260:Female; D006262:Health; D006801:Humans; D008297:Male; D008875:Middle Aged; D057285:Precision Medicine / Q000379:methods*; D012044:Regression Analysis; D018570:Risk Assessment / Q000379:methods*; D019966:Substance-Related Disorders / Q000453:epidemiology* / Q000523:psychology