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Background: The PD MED study reported small but persistent benefits in patient‐rated mobility scores and quality of life from initiating therapy with levodopa compared with levodopa‐sparing therapies in early Parkinson's disease (PD). Objectives: The objective was to estimate the cost‐effectiveness of levodopa‐sparing therapy (dopamine agonists or monoamine oxidase type B inhibitors compared with levodopa alone. Methods: PD MED is a pragmatic, open‐label randomized, controlled trial in which patients newly diagnosed with PD were randomly assigned between levodopa‐sparing therapy (dopamine agonists or monoamine oxidase type B inhibitors) and levodopa alone. Mean quality‐adjusted life‐years and costs were calculated for each participant. Differences in mean quality‐adjusted life‐years and costs between levodopa and levodopa‐sparing therapies and between dopamine agonists and monoamine oxidase type B inhibitors were estimated using linear regression. Results: Over a mean observation period of 4 years, levodopa was associated with significantly higher quality‐adjusted life‐years (difference, 0.18; 95% CI, 0.05–0.30; P < 0.01) and lower mean costs (£3390; £2671–£4109; P < 0.01) than levodopa‐sparing therapies, the difference in costs driven by the higher costs of levodopa‐sparing therapies. There were no significant differences in the costs of inpatient, social care, and institutional care between arms. There was no significant difference in quality‐adjusted life‐years between those allocated dopamine agonists and monoamine oxidase type B inhibitors (0.02; −0.17 to 0.13 in favor of dopamine agonists; P = 0.81); however costs were significantly lower for those allocated monoamine oxidase type B inhibitors (£2321; £1628–£3015; P < 0.01) because of the higher costs of dopamine agonists. There were no significant differences between arms for other costs. Conclusions: Initial treatment with levodopa is highly cost‐effective compared with levodopa‐sparing therapies. Monoamine oxidase type B inhibitors, as initial levodopa‐sparing therapy was more cost‐effective, with similar quality‐adjusted life‐years but lower costs than dopamine agonists. © 2021 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society [ABSTRACT FROM AUTHOR]

Approximately 3.6% of patients with Parkinson's disease develop symptoms before age 45. Early-onset Parkinson's disease (EOPD) patients have a higher familial recurrence risk than late-onset patients, and 3 main recessive EOPD genes have been described. We aimed to establish the prevalence of mutations in these genes in a UK cohort and in previous studies. We screened 136 EOPD probands from a high-ascertainment regional and community-based prevalence study for pathogenic mutations in PARK2 (parkin), PINK1, PARK7 (DJ-1), and exon 41 of LRRK2. We also carried out a systematic review, calculating the proportion of cases with pathogenic mutations in previously reported studies. We identified 5 patients with pathogenic PARK2, 1 patient with PINK1, and 1 with LRRK2 mutations. The rate of mutations overall was 5.1%. Mutations were more common in patients with age at onset (AAO) < 40 (9.5%), an affected first-degree relative (6.9%), an affected sibling (28.6%), or parental consanguinity (50%). In our study EOPD mutation carriers were more likely to present with rigidity and dystonia, and 6 of 7 mutation carriers had lower limb symptoms at onset. Our systematic review included information from >5800 unique cases. Overall, the weighted mean proportion of cases with PARK2 (parkin), PINK1, and PARK7 (DJ-1) mutations was 8.6%, 3.7%, and 0.4%, respectively. PINK1 mutations were more common in Asian subjects. The overall frequency of mutations in known EOPD genes was lower than previously estimated. Our study shows an increased likelihood of mutations in patients with lower AAO, family history, or parental consanguinity. © 2012 Movement Disorder Society. [ABSTRACT FROM AUTHOR]

Interpretation of clinical trials comparing different drug regimens for Parkinson's disease (PD) is complicated by the different dose intensities used: higher doses of levodopa and, possibly, other drugs produce better symptomatic control but more late complications. To address this problem, conversion factors have been calculated for antiparkinsonian drugs that yield a total daily levodopa equivalent dose (LED). LED estimates vary, so we undertook a systematic review of studies reporting LEDs to provide standardized formulae. Electronic database and hand searching of references identified 56 primary reports of LED estimates. Data were extracted and the mean and modal LEDs calculated. This yielded a standardized LED for each drug, providing a useful tool to express dose intensity of different antiparkinsonian drug regimens on a single scale. Using these conversion formulae to report LEDs would improve the consistency of reporting and assist the interpretation of clinical trials comparing different PD medications. © 2010 Movement Disorder Society [ABSTRACT FROM AUTHOR]

Considerable effort has gone into preclinical neuroprotection research in Parkinson's disease (PD) and several large clinical trials have been mounted, but no agent has been conclusively shown to be protective. The latest innovation in PD neuroprotection trial design is the delayed-start design trial. If patients with early PD do better after 12 to 18 months of immediate drug therapy compared to those in whom it is delayed for 6 to 9 months, this is attributed to a neuroprotective effect. However, delayed-start design trials may be fundamentally flawed. It has been suggested that physiological mechanisms compensating for the loss of dopaminergic neurones in early PD may be deleterious and that immediate treatment may prevent such mechanisms and thereby be neuroprotective. If this hypothesis is correct, any drug with a symptomatic effect will be neuroprotective in early PD and delayed-start design trials will show this generic effect, not a neuroprotective effect specific to the drug. Delayed-start design trials require patients to potentially stay untreated for 6 to 9 months. This may lead to the selection of slowly progressive types of PD, such as that in younger patients and those with tremor-dominant disease, so the results may not be generalizable to the majority of patients. Delayed-start design trials are powered to find small differences in total UPDRS score which may not be clinically significant; larger and longer placebo-controlled trials are required to confirm the clinical significance of their findings. These arguments add to the growing tide of opinion for a fundamental rethink of our policy toward neuroprotection research in PD. © 2008 Movement Disorder Society [ABSTRACT FROM AUTHOR]

Rotigotine is a new, non-ergot dopamine agonist formulated in a transdermal delivery system. The present study was to investigate the efficacy and safety of the rotigotine transdermal patch in the treatment of early Parkinson's disease. Patients (n = 561) were randomized to rotigotine, ropinirole, or placebo. The titration period was up to 13 weeks, and there was a minimum dose-maintenance period of 24 weeks for ropinirole and 33 weeks for rotigotine. The primary endpoint was the proportion of patients with a minimum of 20% decrease in the combined Unified Parkinson's Disease Rating Scale Part II and Part III scores. The responder rate in the rotigotine group was significantly higher than in the placebo group (52% vs. 30%, P < 0.0001). Transdermal rotigotine at doses < or =8 mg/24 h did not show noninferiority to ropinirole at doses < or =24 mg/day. In a post-hoc subgroup analysis, rotigotine < or =8 mg/24 hours had a similar efficacy to ropinirole at doses < or =12 mg/day. The rotigotine transdermal patch was well tolerated. The most common adverse events were application-site reactions, nausea, and somnolence. Application-site reactions were predominantly mild or moderate in intensity. In conclusion, the rotigotine transdermal patch represents an effective and safe option for the treatment of patients with early Parkinson's disease. [ABSTRACT FROM AUTHOR]

A 5-year trial of ropinirole and levodopa in early Parkinson's disease showed that ropinirole is associated with reduced incidence of dyskinesias. This post hoc analysis investigated whether the dyskinesia-sparing benefit of ropinirole is lost when levodopa is added to the regimen and evaluated other risk factors for developing dyskinesias. Patients receiving levodopa had a significantly higher risk of dyskinesias than those taking ropinirole monotherapy (hazard ratio [HR], 6.67; 95% confidence interval [CI], 3.23-14.29; P < 0.001). When patients randomized to ropinirole were treated with supplementary levodopa, the development of dyskinesias was not significantly different from that in those receiving levodopa from the start (HR, 0.80; 95% CI, 0.48-1.33; P = 0.39). However, the onset of dyskinesias was delayed by around 3 years compared with levodopa monotherapy. Adjusted analyses taking into account baseline and on-treatment factors that influenced use of supplementary levodopa or the development of dyskinesias produced similar results. In conclusion, the risk of developing dyskinesias during maintained initial ropinirole monotherapy is very low. Only once levodopa is added does the risk substantially change. Early use of ropinirole postpones the onset of dyskinesias, but these benefits decline when levodopa therapy is started, with no evidence of a subsequent rapid 'catch-up' or a persisting preventive effect. © 2006 Movement Disorder Society [ABSTRACT FROM AUTHOR]

Current medical and surgical therapies for Parkinson's disease provide symptomatic control of motor impairments rather than slowing or halting the progression of the disease. Previous clinical trials examining drugs such as dopamine agonists and selegiline for neuroprotective effects used 'surrogate' outcomes, including clinical measures (rating scales, time to require levodopa), neuroimaging techniques (β-CIT single photon emission computed tomography; fluorodopa positron emission tomography), and mortality tracking. These studies failed to provide conclusive results because of design faults such as failing to control for symptomatic effects, small sample size, and not accounting for the possible effects of drugs on radionuclide tracer handling. Lessons must be learned from these failed neuroprotection trials. This review summarises the problems with previous neuroprotection studies and makes recommendations for future trial design. It is concluded that the primary outcome of explanatory trials should continue to be clinical measures such as the Unified Parkinson's Disease Rating Scale (UPDRS). It should be assumed that all agents have a symptomatic effect, which necessitates evaluation after a prolonged drug washout period. To achieve the evaluation after a prolonged drug washout period more effectively, trials must be performed in early disease and over a short period (6-12 months) so that symptomatic therapy is not required. To achieve adequate statistical power, these trials will need to include thousands of patients. Radionuclide imaging can only be used in such trials after considerable methodological work has been performed to establish its validity and reliability. To be affordable, such large explanatory trials need more streamlined designs with fewer hospital visits, fewer outcome measures, and rationalised safety monitoring. The clinical effectiveness of promising compounds from explanatory trials will need to be established in large long-term pragmatic trials using outcome measures such as quality of life, cost-effectiveness, and mortality. Such pragmatic trials could be continuations of the explanatory trials: after the primary outcome of the explanatory study (e.g., UPDRS) has been reported in an interim analysis, the trial could be continued for a further 5 to 10 years to report on quality of life and health economics outcomes. © 2004 Movement Disorder Society [ABSTRACT FROM AUTHOR]