Methods
The study sample included 169 AUD inpatients from eight alcohol treatment facilities in Kathmandu, Nepal. The Composite International Diagnostic Interview was administered to generate the AUD diagnosis. The Alcohol Use Disorder Identification Test (AUDIT) captured AUD severity and patterns of alcohol use. The Hopkins Symptom Checklist-25 was used to reveal current depressive symptoms. Serum kynurenine and tryptophan levels were determined by high-performance liquid chromatography and tryptophan degradation was measured by KT ratio (kynurenine/tryptophan × 103).
Results
Patients with above average AUDIT scores had higher mean serum levels of kynurenine (2.1μM±0.7 vs 1.8 μM ±0.6, p= 0.006) and KT ratios (48.6±17.6 vs 40.4±14.3, p=0.002) than those with below average scores. Patients with current depressive symptoms had higher mean tryptophan concentrations (49.9 μM ±13 vs 45.7 μM±14.1, p= 0.047) and lower KT ratios (41.4 μM ±14 vs 47.5 μM ±17.6, p=0.028) compared to patients whose reported depressive symptoms were below the standard cut-off. Higher tryptophan levels and lower KT ratios in the depressed group was specific to patients with longer abstinence and higher AUD severity.
Conclusions
Depression-related deregulation in tryptophan metabolism was found to depend on length of abstinence and on AUD severity. Together, results suggest that in AUD populations, peripheral tryptophan metabolism is subject to interactions between AUD severity and depressive symptoms.
Link til artikkel
- Forfattere: Neupane, Sudan Prasad; Lien, Lars; Martinez, Priscilla; Hestad, Knut; Bramness, Jørgen Gustav.
- Publisert: Alcoholism: Clinical and Experimental Research 2015 ;Volum 39.(3) s. 514-521