Eleven studies evaluated neuroprotective agents. There were 7 class I studies, 1 class II study and 3 class IV studies.
The authors stated that 22 studies evaluated non-standard pharmacologic and non-pharmacologic therapies. There were 2 class I studies, 11 class II studies, 2 class III studies and 3 class IV studies (total 18 studies; the design of the other studies was not reported).
The number of participants was not reported for all studies.
One class I study, a blinded RCT (n=800), reported no significant difference in the time to require levadopa between vitamin E (2,000 IU/day) and placebo with or without selegiline (hazard ratio 0.91, 95% confidence interval: 0.74, 1.12).
One class I study, a double-blind RCT (n=361), showed that patients on levadopa had significantly improved UPDRS scores compared with patients on placebo at 40 weeks. The change in UPDRS scores was 7.8 on placebo versus 1.9, 1.9 and -1.4, respectively, on three different levadopa doses; the latter showing the greatest improvements associated with the highest dose (600 mg/day). There was no significant difference between treatment groups in SPECT beta-CIT uptake (based on 116 patients) and dyskinesias were more common in patients on 300 mg levadopa.
One class I study, a double-blind RCT (n=404), reported that patients treated with 2 mg rasagiline for 1 year had a smaller increase in UPDRS and UPDRS-ADL scores than patients treated with 2 mg rasagiline for only the previous 6 months (difference 2.29 in UPDRS and -0.96 in UPDRS-ADL, p=0.005).
There was no evidence of a neuroprotective effect for riluzole, coenzyme Q or pramipexole, but studies of riluzole and pramipexole were underpowered (based on 1 class I study for each agent).
There was insufficient evidence to assess the effects of thalamotomy and amantadine (based on 1 class IV study for each treatment).
Non-standard pharmacologic and non-pharmacologic therapies.
Eight class II studies, all blinded RCTs, reported small improvements in various specified functional measures in patients allocated to various exercise interventions; the data were not reported. Studies of speech therapy had sample sizes ranging from 12 to 45; drop-out rates, where reported, ranged from 15 to 27%. Two class II studies showed that individual speech therapy was possibly effective in improving speech volume (one focused on pitch and volume and also used visual feedback; the other was aimed at optimising phonatory effort). There was insufficient information to compare different types of speech therapy.
There was insufficient information to support or refute any of the other therapies evaluated.