Dopaminergic changes have been reported in various forms of dystonia beyond dopa-responsive dystonia (DRD). Besides DRD, levodopa (LDopa) is generally not considered effective in dystonia and may worsen it. This study assesses the impact of LDopa on different dystonia phenotypes.

The patient database of Tampere University Hospital was screened with data mining over a 5-year period to identify individuals with dystonia who had been prescribed LDopa and was evaluated for the possible long-term responsiveness of LDopa in different dystonia phenotypes.

The patient database was screened using data mining to identify dystonia patients associated with LDopa over a 5-year period. Clinical information and response to LDopa were evaluated.

LDopa was considered beneficial with 32 of 71 patients. All DRD patients had long-term benefit of LDopa, as well as 44% generalized dystonia patients and 25% segmental dystonia patients, but none of the focal dystonia patients. Of the seven patients with functional dystonia, four considered LDopa originally beneficial, but the effect was temporary with two patients, resulting in elevating LDopa doses. LDopa benefit was associated positively with lower limb dystonia (OR 7.0, p = 0.002) and negatively with cervical dystonia (OR 0.2, p = 0.001). Moreover, long-term LDopa benefit had a significant correlation with unspecified stiffness (OR 4.0, p = 0.014) and walking difficulties (OR 3.8, p = 0.022).

Other than DRD, LDopa should only be considered in generalized dystonia patients with lower limb dystonia and walking difficulties. Objective estimation of symptoms should be conducted if considering LDopa treatment.