Mortality in substance‐induced psychosis: a register‐based national cohort study

Abstract

Aims We aimed to analyze whether people with substance‐induced psychosis (SIP), both those who convert and do not convert to schizophrenia, have higher all‐cause and cause‐specific mortality when compared to the general population. Design Prospective cohort study. Setting Nationwide Danish registers. Participants/Cases We included all people born in Denmark, living in Denmark on their 15th birthday, and age 15 or more during the study period from January 1, 1994, and August 10, 2017. Measurements Exposure was categorized as: (i) neither SIP nor schizophrenia; (ii) SIP without preceding schizophrenia; (iii) SIP converted to schizophrenia; and (iv) schizophrenia without preceding SIP. Any SIP and substance‐specific SIPS were examined regarding all‐cause and cause‐specific mortality. Findings The study included a total of 5 619 691 individuals. Compared to people with neither schizophrenia nor SIP, people with SIP without preceding schizophrenia had an increased risk of dying (hazard ratio [HR] = 6.23, 95% CI = 5.96–6.50), as had those with SIP converting to schizophrenia (HR = 9.77, 95% CI = 8.84–10.79) and those with only schizophrenia (HR = 3.07, 95% CI = 3.03–3.13). A similar pattern, albeit with higher HRs, was observed for suicides and accidental deaths. Other cause‐specific‐mortality groups also generally showed the same pattern, as did types of individual substances. Conclusions Substance‐induced psychosis was strongly associated with an increased risk of both all‐cause and cause‐specific mortality, even among cases who did not convert to schizophrenia. This provides a strong rationale for monitoring people with previous diagnosis of substance‐induced psychosis and developing and implementing interventions to reduce this excess mortality.

Mortality in psychotic depression: 18-year follow-up study

“…Previous research has showed that comorbid personality disorder and substance use disorders are more common in those with psychotic depression than in people with non-psychotic depression, 7 , 20 and that personality disorder and substance use disorders are associated with psychosis and with increased mortality. 22 – 24 Our findings showed that these conditions did not explain the excess mortality in those with psychotic depression compared with severe non-psychotic depression. In other words, although these psychiatric comorbidities may add to the total burden of psychiatric morbidity, other factors are more important in determining the excess risk of mortality in psychotic depression.…”

Anthropometry in antipsychotic-naïve first-episode psychosis patients: An exploratory approach to the role of environmental early life events in two independent samples

“…Patients with schizophrenia exhibit a reduced life expectancy compared with the general population of about 15 years (Hjorthøj et al, 2017). Although diverse psychopathological conditions, such as increased substance abuse (Hjorthøj et al, 2021), unhealthy lifestyles (Jakobsen et al, 2018), or suicide risk might confound those results, the main reasons for the increased morbidity and early mortality are medical-conditions such as cardiovascular diseases or type 2 diabetes mellitus (T2DM) (Chan et al, 2021). Current literature suggests that the risk of previous medical conditions is increased by gestational problems (Hales and Barker, 1992).…”

Association between substance‐induced psychosis and suicide attempt: A Danish nation‐wide register‐based study

“…Approximately 600 incident cases of any type of treated substance‐induced psychosis occur on a yearly basis in Denmark, and during recent years an increasing trend has been observed for cannabis‐induced psychosis [2]. Although the body of evidence regarding substance‐induced psychosis is limited, individuals with substance‐induced psychosis are found to have elevated risks of all‐cause and cause‐specific mortality, including suicide [3].…”