Alpha-1-acid glycoprotein in major depressive disorder. Relationships to severity, response to treatment and imipramine plasma levels.
BACKGROUND
Increased plasma levels of alpha-1-acid glycoprotein (AGP) were reported in major depressive disorder. However, the relationship between AGP levels, severity of depression, treatment response and antidepressant levels are still unclear.


METHODS
Plasma AGP levels were measured in 36 subjects with major depressive disorder before and after a 6-week treatment with imipramine and in 30 controls. Free imipramine plasma levels of depressed patients were measured at 6 weeks. Comparative analysis between depressed patients and controls, between non-responders (N = 12) and responders (N = 24), and between severely depressed patients (N = 14) and moderately depressed patients (N = 22) were made.


RESULTS
Depressed patients had significantly higher mean values of AGP than control subjects. Imipramine non-responders and specially severely depressed patients had significantly greater increases of AGP levels during treatment than other depressed subgroups. There was no correlation between baseline AGP levels and severity of depression or free imipramine levels.


CONCLUSIONS
The most significant limitations of this study are the small sample size and the fact that all the subjects were out-patients. Results should not be generalized to in-patient populations.


CONCLUSIONS
Depressed patients showed high baseline concentrations of AGP. AGP levels did not predict either free imipramine plasma levels or differential response after 6 weeks of treatment with imipramine. A greater increase of AGP during treatment was associated with severity of depression and treatment non-response.


CONCLUSIONS
The relationship between high plasma levels of AGP, severity of depression and lack of treatment response is clarified. The influence of imipramine levels is minimized.
Nieto
E
E
Department of Psychiatry, Hospital Clinic de Barcelona, Villarroel 170, 08036, Barcelona, Spain. ddhossch@jaguar1.usouthal.edu
Vieta
E
E
Alvarez
L
L
Torra
M
M
Colom
F
F
Gastó
C
C
D000293:Adolescent; D000328:Adult; D000929:Antidepressive Agents, Tricyclic / Q000097:blood* / Q000627:therapeutic use; D015415:Biomarkers / Q000097:blood; D016022:Case-Control Studies; D003865:Major Depressive Disorder / Q000097:blood* / Q000188:drug therapy*; D005260:Female; D006801:Humans; D007099:Imipramine / Q000097:blood* / Q000627:therapeutic use; D008297:Male; D008875:Middle Aged; D009961:Orosomucoid / Q000187:drug effects / Q000378:metabolism*; D010045:Outpatients / Q000706:statistics & numerical data; D012720:Severity of Illness Index; D016896:Treatment Outcome
D000929:Antidepressive Agents, Tricyclic; D015415:Biomarkers; D009961:Orosomucoid; D007099:Imipramine