Muscle sympathetic nervous activity in depressed patients before and after treatment with sertraline.
BACKGROUND
Sympathetic hyperactivity is one of the mechanisms involved in the increased cardiovascular risk associated with depression, and there is evidence that antidepressants decrease sympathetic activity.


OBJECTIVE
We tested the following two hypotheses: patients with major depressive disorder with high scores of depressive symptoms (HMDD) have augmented muscle sympathetic nervous system activity (MSNA) at rest and during mental stress compared with patients with major depressive disorder with low scores of depressive symptoms (LMDD) and controls; sertraline decreases MSNA in depressed patients.


METHODS
Ten HMDD, nine LMDD and 11 body weight-matched controls were studied. MSNA was directly measured from the peroneal nerve using microneurography for 3 min at rest and 4 min during the Stroop color word test. For the LMDD and HMDD groups, the tests were repeated after treatment with sertraline (103.3 +/- 40 mg).


RESULTS
Resting MSNA was significantly higher in the HMDD [29.1 bursts/min (SE 2.9)] compared with LMDD [19.9 (1.6)] and controls [22.2 (2.0)] groups (P = 0.026 and 0.046, respectively). There was a significant positive correlation between resting MSNA and severity of depression. MSNA increased significantly and similarly during stress in all the studied groups. Sertraline significantly decreased resting MSNA in the LMDD group and MSNA during mental stress in LMDD and HMDD groups. Sertraline significantly decreased resting heart rate and heart rate response to mental stress in the HMDD group.


CONCLUSIONS
Moderate-to-severe depression is associated with increased MSNA. Sertraline treatment reduces MSNA at rest and during mental challenge in depressed patients, which may have prognostic implications in this group.
Scalco
Andréia Zavaloni
AZ
Department of Psychiatry and Behavioural Neurosciences, McMaster University, Hamilton, Ontario, Canada. scalcoa@mcmaster.ca
Rondon
Maria Urbana Pinto Brandão
MU
Trombetta
Ivani Credidio
IC
Laterza
Mateus Camaroti
MC
Azul
João Batista Costa Carvalho
JB
Pullenayegum
Eleanor Maria
EM
Scalco
Mônica Zavaloni
MZ
Kuniyoshi
Fátima Helena Sert
FH
Wajngarten
Maurício
M
Negrão
Carlos Eduardo
CE
Lotufo-Neto
Francisco
F
D000293:Adolescent; D000328:Adult; D001794:Blood Pressure / Q000187:drug effects; D002316:Cardiotonic Agents / Q000627:therapeutic use; D003071:Cognition / Q000187:drug effects / Q000502:physiology; D003866:Depressive Disorder / Q000188:drug therapy* / Q000378:metabolism; D004594:Electrophysiology; D005260:Female; D006801:Humans; D008297:Male; D008839:Microelectrodes; D008875:Middle Aged; D018482:Muscle, Skeletal / Q000294:innervation*; D010543:Peroneal Nerve / Q000378:metabolism; D011581:Psychological Tests; D012039:Regional Blood Flow / Q000187:drug effects; D017367:Selective Serotonin Reuptake Inhibitors / Q000627:therapeutic use*; D020280:Sertraline / Q000627:therapeutic use*; D013315:Stress, Psychological; D013564:Sympathetic Nervous System / Q000378:metabolism*; D055815:Young Adult
D002316:Cardiotonic Agents; D017367:Selective Serotonin Reuptake Inhibitors; D020280:Sertraline