Transdermal Nicotine Treatment and Progression of Early Parkinson's Disease.
Level 2 - randomized trial
Individual randomized controlled trial
PubMed 38320207 · doi:10.1056/EVIDoa2200311
What was done
In a double-blind, placebo-controlled multicenter randomized controlled trial, patients with early Parkinson's disease (diagnosed within 18 months, Hoehn and Yahr stage ≤ 2, therapy-naive except for stable monoamine-oxidase-B inhibitors, not requiring dopaminergic therapy) were assigned to transdermal nicotine or placebo. The primary endpoint was change in Total Unified Parkinson's Disease Rating Scale (UPDRS parts I–III, score 0–172) from baseline to 60 weeks (52 weeks of treatment followed by an 8-week washout). The first secondary endpoint was change in Total UPDRS from baseline to 52 weeks. Between-group differences were estimated using the Hodges–Lehmann (HL) method and tested with the exact two-sided stratified Mann–Whitney–Wilcoxon test.
What was found
Among 163 participants, 101 were assessed for the primary endpoint at 60 weeks. Mean worsening of Total UPDRS was 3.5 in the placebo group versus 6.0 in the nicotine group (HL difference: −3 [95% CI: −6 to 0], P = 0.06). At 52 weeks (n = 138), mean worsening was 5.4 in the placebo group versus 9.1 in the nicotine group (HL difference: −4 [95% CI: −7 to −1]). Cutaneous adverse effects at the patch site were common, and 34.6% of participants initiated dopaminergic therapy during the study.
Why it matters
Despite epidemiologic evidence linking smoking to lower Parkinson's disease incidence, one-year transdermal nicotine failed to slow clinical progression in early-stage disease and was associated with numerically greater worsening.
Limits
There was substantial dropout, with only 101 of 163 participants completing the 60-week primary endpoint evaluation. Frequent cutaneous adverse events led to treatment discontinuation, and 34.6% of participants initiated confounding dopaminergic therapy.
Cited by
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