Continuous subcutaneous apomorphine infusion in Parkinson’s disease: causes of discontinuation and subsequent treatment strategies

Continuous subcutaneous apomorphine infusion (CSAI) is a well-recognized therapeutic option for the management of motor fluctuations in Parkinson's disease (PD), although clinical experience suggests that most patients discontinue CSAI after a variable amount of time due to several causes and circumstances. The objective of the present study was to evaluate the reasons of CSAI discontinuation and to investigate which treatment was adopted afterwards. Two independent raters retrospectively reviewed the electronic medical record of 114 patients treated with CSAI for at least 6 months. The records were reviewed regarding efficacy, safety, and evolution of CSAI treatment. Most of PD patients on CSAI had a significant improvement in their clinical condition. Lack of improvement of dyskinesia was the most frequent causes of treatment discontinuation. The second reason for CSAI discontinuation was cognitive deterioration. At CSAI discontinuation, younger patients were more likely to undergo deep brain stimulation (DBS), while older patients and patients with cognitive impairment were more likely switched to oral therapy alone (OTA). CSAI is an effective treatment that unfortunately must be discontinued in a great number of patients with advanced PD. As older age is the main limiting factor for accessing second-level therapies at CSAI discontinuation, CSAI treatment should not be postponed to older age. CSAI might be considered a good first-line and fast strategy in patients undergoing rapid deterioration of their quality of life while waiting for DBS or levodopa/carbidopa intestinal gel therapy.