Clinical correlates of low serum carnitine levels in hospitalized psychiatric patients

Abstract

Objective: We sought to evaluate clinical correlates of low serum carnitine levels in hospitalized psychiatric patients.

Methods: We retrospectively reviewed the charts of 40 psychiatric inpatients identified to have low serum carnitine levels.

Results: Cognitive impairment was present in 38 (95%) cases, frequently accompanied by imbalance, agitation and extrapyramidal symptoms. Valproate therapy was encountered in 28 (70%) patients. The dosage of valproate negatively correlated with total and free carnitine levels (P = 0.003 and 0.0136). Polypharmacy also affected carnitine levels, indicating additional modulatory effects on carnitine metabolism. We encountered a disproportionately high prevalence of mental retardation and dementia in association with hypocarnitinemia.

Conclusion: We hypothesize that in the context of mental illness hypocarnitinemia may be associated with metabolic encephalopathy and cognitive impairment. As carnitine deficiency is a potentially treatable condition further studies are warranted.