TY - JOUR
T1 - Morbidity and mortality in schizophrenia with comorbid substance use disorders
AU - Lähteenvuo, Markku
AU - Batalla, Albert
AU - Luykx, Jurjen J.
AU - Mittendorfer-Rutz, Ellenor
AU - Tanskanen, Antti
AU - Tiihonen, Jari
AU - Taipale, Heidi
N1 - Funding Information:
JT, EMR, HT and AT have participated in research projects funded by grants from Janssen‐Cilag and Eli Lilly to their employing institution. HT reports personal fees from Janssen‐Cilag. JT reports personal fees from the Finnish Medicines Agency (Fimea), European Medicines Agency (EMA), Eli Lilly, Janssen‐Cilag, Lundbeck and Otsuka, is a member of advisory board for Lundbeck and has received grants from the Stanley Foundation and Sigrid Jusélius Foundation. ML is a board member of Genomi Solutions ltd. and DNE Ltd., has received honoraria from Sunovion Ltd., Orion Pharma ltd. and Janssen‐Cilag, and research funding from The Finnish Medical Foundation and Emil Aaltonen Foundation. AB and JL declare no competing interests.
Funding Information:
This study was funded by the Finnish Ministry of Social Affairs and Health through the developmental fund for Niuvanniemi Hospital. HT was funded by Academy of Finland (grants 315969, 320107). ML was partly funded by personal grants from the Finnish Medical Foundation and Emil Aaltonen foundation. We would like to thank ms Aija Räsänen for secretarial assistance. The funders of the study had no role in study design, data collection, data analysis, data interpretation, or writing of the report. The corresponding authors had full access to all of the data and the final responsibility to submit for publication.
Publisher Copyright:
© 2021 The Authors. Acta Psychiatrica Scandinavica published by John Wiley & Sons Ltd.
PY - 2021/7
Y1 - 2021/7
N2 - Objective: Schizophrenia is highly comorbid with substance use disorders (SUD) but large epidemiological cohorts exploring the prevalence and prognostic significance of SUD are lacking. Here, we investigated the prevalence of SUD in patients with schizophrenia in Finland and Sweden, and the effect of these co-occurring disorders on risks of psychiatric hospitalization and mortality. Methods: 45,476 individuals with schizophrenia from two independent national cohort studies, aged <46 years at cohort entry, were followed during 22 (1996–2017, Finland) and 11 years (2006–2016, Sweden). We first assessed SUD prevalence (excluding smoking). Then, we performed Cox regression on risk of psychiatric hospitalization and all-cause and cause-specific mortality in SUD compared with those without SUD. Results: The prevalence of SUD ranged from 26% (Finland) to 31% (Sweden). Multiple drug use (n = 4164, 48%, Finland; n = 3268, 67%, Sweden) and alcohol use disorders (n = 3846, 45%, Finland; n = 1002, 21%, Sweden) were the most prevalent SUD, followed by cannabis. Any SUD comorbidity, and particularly multiple drug use and alcohol use, were associated with 50% to 100% increase in hospitalization (aHR any SUD: 1.53, 95% CI = 1.46–1.61, Finland; 1.83, 1.72–1.96, Sweden) and mortality (aHR all-cause mortality: 1.65, 95% CI = 1.50–1.81, Finland; 2.17, 1.74–2.70, Sweden) compared to individuals without SUD. Elevated mortality risks were observed especially for suicides and other external causes. All results were similar across countries. Conclusion: Co-occurring SUD, and particularly alcohol and multiple drug use, are associated with high rates of hospitalization and mortality in schizophrenia. Preventive interventions should prioritize detection and tailored treatments for these comorbidities, which often remain underdiagnosed and untreated.
AB - Objective: Schizophrenia is highly comorbid with substance use disorders (SUD) but large epidemiological cohorts exploring the prevalence and prognostic significance of SUD are lacking. Here, we investigated the prevalence of SUD in patients with schizophrenia in Finland and Sweden, and the effect of these co-occurring disorders on risks of psychiatric hospitalization and mortality. Methods: 45,476 individuals with schizophrenia from two independent national cohort studies, aged <46 years at cohort entry, were followed during 22 (1996–2017, Finland) and 11 years (2006–2016, Sweden). We first assessed SUD prevalence (excluding smoking). Then, we performed Cox regression on risk of psychiatric hospitalization and all-cause and cause-specific mortality in SUD compared with those without SUD. Results: The prevalence of SUD ranged from 26% (Finland) to 31% (Sweden). Multiple drug use (n = 4164, 48%, Finland; n = 3268, 67%, Sweden) and alcohol use disorders (n = 3846, 45%, Finland; n = 1002, 21%, Sweden) were the most prevalent SUD, followed by cannabis. Any SUD comorbidity, and particularly multiple drug use and alcohol use, were associated with 50% to 100% increase in hospitalization (aHR any SUD: 1.53, 95% CI = 1.46–1.61, Finland; 1.83, 1.72–1.96, Sweden) and mortality (aHR all-cause mortality: 1.65, 95% CI = 1.50–1.81, Finland; 2.17, 1.74–2.70, Sweden) compared to individuals without SUD. Elevated mortality risks were observed especially for suicides and other external causes. All results were similar across countries. Conclusion: Co-occurring SUD, and particularly alcohol and multiple drug use, are associated with high rates of hospitalization and mortality in schizophrenia. Preventive interventions should prioritize detection and tailored treatments for these comorbidities, which often remain underdiagnosed and untreated.
KW - addiction
KW - mortality
KW - psychosis
KW - schizophrenia
KW - substance use disorder
UR - http://www.scopus.com/inward/record.url?scp=85102206553&partnerID=8YFLogxK
U2 - 10.1111/acps.13291
DO - 10.1111/acps.13291
M3 - Article
C2 - 33650123
AN - SCOPUS:85102206553
SN - 0001-690X
VL - 144
SP - 42
EP - 49
JO - Acta Psychiatrica Scandinavica
JF - Acta Psychiatrica Scandinavica
IS - 1
ER -