Acetyl-l-carnitine deficiency in patients with major depressive disorder.
Level 4 - case-series / case-control
Multi-center case-control study comparing biomarker levels between clinical cases and matched controls
PubMed 30061399 · doi:10.1073/pnas.1801609115
What was done
Following rodent mechanistic studies, circulating acetyl-l-carnitine (LAC) and free carnitine levels were measured in patients with major depressive disorder (MDD) and age- and sex-matched healthy controls across two independent study centers. Secondary exploratory analyses evaluated associations with depression severity, age of onset, treatment-resistant depression (TRD), and childhood trauma.
What was found
The abstract reports no numerical values, concentrations, or statistical significance metrics. Circulating LAC levels, but not free carnitine, were reported as decreased in MDD patients compared with healthy controls at both centers. Greater LAC decreases correlated with greater severity, earlier onset, and TRD status, with female sex and childhood emotional neglect predicting lower LAC in TRD patients.
Why it matters
This study identifies acetyl-l-carnitine deficiency as a candidate biomarker for a severe, treatment-resistant endophenotype of depression that may inform targeted clinical trials.
Limits
The abstract gives no sample sizes, demographic parameters, exact biomarker concentrations, or effect sizes. As an observational case-control design, it cannot prove that low LAC causes depressive symptoms, and subgroup findings reflect exploratory secondary analyses.
Cited by
- supports Acetyl-L-carnitine is low in patients with depression and increases or resolves in association with antidepressant treatment response.