Which Scale Best Detects Treatment Response of Tremor in Parkinsonism?
BACKGROUND
Several scales are available for rating the severity of tremor at present. However, the sensitivity to change of these instruments has remained to be clarified.


OBJECTIVE
To compare the sensitivity of the Fahn-Tolosa-Marin Tremor Rating Scale, the Part III of the Movement Disorder Society-sponsored Unified Parkinson's Disease Rating Scale (MDS-UPDRS) and the MDS-UPDRS Tremor Scale to the effects of various antitremor treatments.


METHODS
Enrolling subjects with parkinsonism associated with tremor, we analyzed two scenarios: (1) tremor changes associated with acute levodopa challenge (n = 287) and (2) a 12-month outcome of different treatment options (n = 512) including deep brain stimulation (n = 146), levodopa/carbidopa intestinal gel infusion (n = 30), and initiating (n = 63) or adjusting oral antiparkinsonian medication (n = 273). Changes in tremor scales were assessed by effect size values (Cohen's d and eta-square).


RESULTS
Part B of the Fahn-Tolosa-Marin Tremor Rating Scale was the most sensitive to acute levodopa challenge (Cohen's d = -1.04, η2 = 0.12). However, Part A of the Fahn-Tolosa-Marin Tremor Rating Scale showed the highest effect size, which was a small one (Cohen's d = -0.33, η2 = 0.03), for detecting a treatment-related change in the severity of tremor during long-term follow-up.


CONCLUSIONS
The Fahn-Tolosa-Marin Tremor Rating Scale has a better ability to capture changes due to levodopa challenge or antiparkinsonian treatment than MDS-UPDRS Part III or MDS-UPDRS Tremor Scale.
['Pintér|Dávid|D|', 'Forjaz|Maria João|MJ|', 'Martinez-Martin|Pablo|P|', 'Rodriguez-Blazquez|Carmen|C|', 'Ayala|Alba|A|', 'Juhász|Annamária|A|', 'Harmat|Márk|M|', 'Janszky|József|J|', 'Kovács|Norbert|N|']
D000328:Adult D000368:Aged D000978:Antiparkinson Agents D002230:Carbidopa D046690:Deep Brain Stimulation D004338:Drug Combinations D005260:Female D005500:Follow-Up Studies D006801:Humans D007980:Levodopa D008297:Male D008875:Middle Aged D017063:Outcome Assessment, Health Care D020734:Parkinsonian Disorders D012680:Sensitivity and Specificity D012720:Severity of Illness Index D014202:Tremor
treatment response tremor Parkinsonism rating scales