Premium
Suicide and self‐harm following prescription of SSRIs and other antidepressants: confounding by indication
Author(s) -
Didham Rebecca C.,
McConnell Doug W.,
Blair Hayden J.,
Reith David M.
Publication year - 2005
Publication title -
british journal of clinical pharmacology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.216
H-Index - 146
eISSN - 1365-2125
pISSN - 0306-5251
DOI - 10.1111/j.1365-2125.2005.02480.x
Subject(s) - suicidal ideation , medicine , depression (economics) , confounding , medical prescription , antidepressant , psychiatry , poison control , paroxetine , suicide attempt , suicide prevention , emergency medicine , pharmacology , anxiety , economics , macroeconomics
Aim To identify the incidence and risk of suicide and self harm, among patients prescribed antidepressant drugs. Methods A retrospective cohort study, with nested case control, of patients identified from a nonrandom sample of general practices in New Zealand from 1996 to 2001. A total of 57 361 patients who received a prescription for a single antidepressant were identified from the RNZCGP Research Unit Database. Suicides within 120 days of a prescription were identified from the New Zealand National Mortality Database and self‐harm events within 120 days of a prescription were identified from the New Zealand Hospital discharge database. Results 26 suicides and 330 episodes of self‐harm were identified within 120 days of an antidepressant prescription. On univariate analysis the association, expressed as OR (95% CI), between selective serotonin reuptake inhibitors (SSRIs) and self harm and suicide were 2.26 (1.27–4.76) and 1.92 (0.77–4.83), respectively. When corrected for the confounding effects of age, gender and depression/suicidal ideation there was an association between SSRIs and self harm, OR 1.66 (95% CI 1.23–2.23), but not for suicide, 1.28 (0.38–4.35). Paroxetine was a significant risk factor for suicide on univariate analysis, 4.23 (1.19–14.95), but not when corrected for age, gender and depression/suicidal ideation, 2.76 (0.30–24.87). Conclusions Age, gender and pre‐existing depression/suicidal ideation are important confounders in observational studies of the association between antidepressants and suicide or self harm.