Gambling disorder and other impulse control disorders associated with pramipexole: a nationwide Swedish case-control study

Background Pramipexole, a dopamine agonist, is commonly prescribed for restless leg syndrome and Parkinson’s disease. However, it has been linked to gambling disorders and other impulse control disorders developing as a side effect. In this report, we investigated the impact of pharmacological factors and psychiatric comorbidities on the risk of developing these side effects in the Swedish patient population. Methods Data was obtained from the Swedish National Patient Records and National Pharmacological Records. Cases ( n = 189) had been prescribed pramipexole and subsequently diagnosed with gambling or another impulse control disorder. A 3-to-1 matching was undertaken, accounting for demographic and clinical factors. Pramipexole dose, treatment duration, levodopa co-prescription and psychiatric comorbidities were investigated by bivariate analysis and logistic regression. Additionally, neurological and psychiatric subgroups were investigated for subgroup-specific risk factors. Results Longer treatment duration increased the risk of gambling or another impulse control disorder in the full cohort ( p < 0.001, OR = 1.13, 95% CI:1.05–1.22), whereas increased pramipexole doses did not ( p = 0.602). Recent pramipexole therapy was a risk factor ( p = 0.002, OR = 2.14, 95% CI:1.32–3.48), as were mood and anxiety disorders ( p < 0.001, OR = 1.98, 95% CI:1.35–2.91) and ( p = 0.017, OR = 1.66, 95% CI:1.10–2.51) respectively. Levodopa co-prescription was shown to increase risk in Parkinson’s disease patients by Chi-Squared testing ( p = 0.046, Phi = 0.15). Conclusion This study highlights the influence of pharmacological and psychiatric factors, which may aid in identifying at-risk patients and improving the clinical tailoring of pramipexole therapy. Clinical trial number Not applicable.