Nationwide population-based register linkage study covering the entire 5.9 million inhabitants in Denmark systematically investigating the associations between sustained long-term use of lithium versus lamotrigine and valproate, and the risk of a range of physical disorders emulating a randomized trial.

The study includes two cohorts. Cohort 1: all 12.607 patients with a diagnosis of bipolar disorder (ICD-10 code: DF30-31.9) who subsequently were exposed to either lithium, lamotrigine or valproate between 1997 and 2021. Cohort 2: as Cohort 1, but regardless of prior diagnosis of bipolar disorder (N= 156.678).

Main analyses considered a patient exposed to a drug 92 days after a prescription and a 10-year follow-up and 4 sensitivity analyses considered a patient exposed to a drug for 60 and 180 days after a prescription, respectively, and with 5- and 15-years follow-up, respectively.

Inclusion Criteria:

• diagnosis of bipolar disorder and subsequent exposure to either lithium, lamotrigine or valproate

Exclusion Criteria:

• None

Nationwide population-based register linkage study covering the entire 5.9 million inhabitants in Denmark and two cohorts. Cohort 1: all 12.607 patients with a diagnosis of bipolar disorder (ICD-10 code: DF30-31.9) who subsequently were exposed to either lithium, lamotrigine or valproate between 1997 and 2021. Cohort 2: as Cohort 1, but regardless of prior diagnosis of bipolar disorder (N= 156.678).