Two Faces of Catechol-O-Methyltransferase Inhibitor on One-Carbon Metabolism in Parkinson's Disease: A Meta-Analysis

source extracted confidence: high 2026-04-09
#humans #carbon #folic-acid #homocysteine #levodopa

Two Faces of Catechol-O-Methyltransferase Inhibitor on One-Carbon Metabolism in Parkinson's Disease: A Meta-Analysis

Kim et al., 2023 | Nutrients | Meta Analysis

Citation

Kim Jin Hee, Jin Shaoyue, ... Lim Yunsook. Two Faces of Catechol-O-Methyltransferase Inhibitor on One-Carbon Metabolism in Parkinson's Disease: A Meta-Analysis. Nutrients. 2023-Feb-10;15(4). doi:10.3390/nu15040901

Abstract

Levodopa (L-dopa) and catechol-O-methyltransferase (COMT) inhibition are widely used therapeutics in Parkinson's disease (PD). Despite their therapeutic effects, it was raised that nutrients involved in one-carbon metabolism can be deteriorated by PD therapies. The aim of this meta-analysis was to investigate the impact of L-dopa and COMT inhibitors on levels of homocysteine (Hcy), vitamin B12 and folate in patients with PD. A total of 35 case-control studies from 14 different countries were selected through PubMed, MEDLINE and Google Scholar and were meta-analyzed. In the L-dopa group, the Hcy level was higher compared to the PD without L-dopa group (SMD: 5.11 μmol/L, 95% CI: 3.56 to 6.66). Moreover, vitamin B12 and folate levels in the L-dopa group were lower compared to the healthy control (SMD: -62.67 pg/mL, 95% CI: -86.53 to -38.81; SMD: -0.89 ng/mL, 95% CI: -1.44 to -0.33, respectively). The COMT inhibitor group showed lower levels of Hcy (SMD: -3.78 μmol/L, 95% CI: -5.27 to -2.29) and vitamin B12 (SMD: -51.01 pg/mL, 95% CI: -91.45 to -10.57), but higher folate levels (SMD: 1.78 ng/mL, 95% CI: -0.59 to 4.15) compared to the L-dopa group. COMT inhibitors may ameliorate L-dopa-induced hyper-homocysteine and folate deficiency but exacerbate vitamin B12 deficiency.

Key Findings

COMT inhibitors may ameliorate L-dopa-induced hyper-homocysteine and folate deficiency but exacerbate vitamin B12 deficiency.

Outcomes Measured

  • Requires manual extraction

Population

Field Value
Population pd
Sample Size See abstract
Age Range See abstract
Condition deficiency

MeSH Terms

  • Humans
  • Carbon
  • Folic Acid
  • Homocysteine
  • Levodopa
  • Parkinson Disease
  • Vitamin B 12
  • Vitamins
  • Catechol O-Methyltransferase Inhibitors

Evidence Classification

  • Level: Meta Analysis
  • Publication Types: Meta-Analysis, Journal Article
  • Vertical: vitamin-b12

Provenance

Source extracted via PubMed E-utilities API on 2026-04-09