Adherence to psychotropic medication in completed suicide in Sweden 2006–2013: a forensic-toxicological matched case-control study

• Published in: European journal of clinical pharmacology Vol. 75; no. 10; pp. 1421 - 1430
• Main Authors: Forsman, Jonas, Taipale, Heidi, Masterman, Thomas, Tiihonen, Jari, Tanskanen, Antti
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01-10-2019; Springer Nature B.V
• Subjects: Adult; Aged; Antidepressants; Antipsychotics; Autopsies; Autopsy; Biomedical and Life Sciences; Biomedicine; Case-Control Studies; Death; Drug therapy; Female; Forensic science; Humans; Male; Medication Adherence; Medicin och hälsovetenskap; Middle Aged; Pharmacoepidemiology and Prescription; Pharmacology/Toxicology; Psychotropic drugs; Psychotropic Drugs - therapeutic use; Registries; Statistical analysis; Substance abuse treatment; Suicide; Suicide, Completed - statistics & numerical data; Sweden - epidemiology; Sweden; Pharmacoepidemiology; Antipsychotics; Compliance; Suicide; Antidepressives
• ISSN: 0031-6970; 1432-1041; 1432-1041
• DOI: 10.1007/s00228-019-02707-z

Objective
To investigate the influence of adherence to psychotropic medications upon the risk of completed suicide by comparing person-level prescriptions and postmortem toxicological findings among complete-suicide cases and non-suicide controls in Sweden 2006–2013.
Methods
Using national registries with full coverage on dispensed prescriptions, results of medico-legal autopsies, causes of death, and diagnoses from inpatient care, estimated continuous drug use for 30 commonly prescribed psychotropic medications was compared with forensic-toxicological findings. Subjects who had died by suicide (cases) were matched (1:2) with subjects who had died of other causes (controls) for age, sex, and year of death. Odds ratios were calculated using logistic regression to estimate the risk of completed suicide conferred by partial adherence and non-adherence to pharmacotherapy. Adjustments were made for previous inpatient care and the ratio of initiated and discontinued dispensed prescriptions, a measure of the continued need of treatment preceding death.
Results
In 5294 suicide cases and 9879 non-suicide controls, after adjusting for the dispensation ratio and other covariates, partial adherence and non-adherence to antipsychotics were associated with 6.7-fold and 12.4-fold risks of completed suicide, respectively, whereas corresponding risk estimates for antidepressant treatment were not statistically significant and corresponding risk increases for incomplete adherence to antidepressant treatment were lower (1.6-fold and 1.5-fold, respectively) and lacked statistical significance.
Conclusion
After adjustment for the need of treatment, biochemically verified incomplete adherence to antipsychotic pharmacotherapy was associated with markedly increased risks of completed suicide.