Suicide and suicidality after exposure to finasteride (Suicidality with finasteride)

Finasteride – indicated for benign prostatic hyperplasia (BPH) and male pattern hair loss (MPHL) - is known to cause psychiatric side effects. There are ongoing signals of persistence of psychiatric events after discontinuation of finasteride and of suicide/self-injury which remain under close monitoring. The principal objectives of this study are: (i) to assess the extent to which patients prescribed finasteride 5mg (BPH indication) are at increased risk of recorded suicide and suicide-related outcomes compared with patient prescribed alternative treatments for BPH, (ii) to assess if any association between finasteride 5mg exposure and recorded suicidality persists after cessation of therapy, and (iii) to describe the pattern of recorded events in patients prescribed finasteride 1mg (MPHL indication). This will be a cohort study with cohorts defined based on patients’ exposure to the medicines under investigation. The population eligible for the study will consist of male patients (finasteride is not indicated for use in females) registered with an IMRD-UK registered GP-practice for a duration of one-year or more. To avoid potential confounding relating to differing baseline risks a covariate adjusted analysis will be used. This will require the use of a minimum one-year lookback period prior to the start of follow-up to establish any baseline comorbidities. The primary analysis will be a new-user “inception” cohort of patients established through the one-year screening period to define incident use. Patients will be followed from the date of first prescription until an event or censored. The primary (composite) analysis will follow-up until first event and the secondary (component part / alternative composite) analysis will follow-up until first event of each type. Patients will be censored at the end of follow-up or when they switch to alternative therapy for BPH.