To assess the outcomes of patients with ataxia evaluated for paraneoplastic syndrome primarily in an outpatient or inpatient setting.

Although paraneoplastic ataxias are rare, affecting 1-2/1000 patients diagnosed with cancer, neurologists routinely consider them as part of the workup for ataxia. There is no evidence guiding whether outcomes differ when patients undergo inpatient or outpatient workup.

This study is a retrospective analysis evaluating the records of all adult patients with ataxia who underwent workup for paraneoplastic syndrome from March 2011 until June 2018 at Rush University Hospital. Baseline functional status, diagnosis, workup, and ambulatory outcomes of patients were recorded.  Using t test or Mann-Whitney U test and Chi-square test or Fisher’s exact test, we compared outcomes between those who underwent workup primarily as an inpatient compared to outpatient.

There were 79 patients included in the analysis: 19 patients (24%) underwent evaluation as an inpatient, and 60 (85.7%) underwent workup as an outpatient. Patients who underwent inpatient workup were more likely to receive immunotherapy 13/19 (68.4%) compared to outpatients 12/60 (20%) (P<0.0001). When immunotherapy was used, those who underwent inpatient workup received treatment in a significantly shorter period than those with outpatient work-ups (median 0.4 months (IQR=0.97) from presentation vs. median 6.3 months (IQR= 8.85) (P=0.02).  Patients admitted for workup were more likely to receive a specific diagnosis for their ataxia: 17/19 (89.47%) compared to 35/60 (58.33%) of those with outpatient evaluations (P=0.01). Those who received a diagnosis received it significantly faster in the inpatient group than those who underwent outpatient workup, 0.16 months (IQR=0.8) compared to 2 months (IQR= 6.7) respectively (P=0.03).

This study shows that patients who undergo workup for paraneoplastic cerebellar degeneration as an inpatient are more likely to receive a specific diagnosis and immunotherapy, and receive them faster than patients evaluated as an outpatient.