Neurological soft signs are increased in major depressive disorder irrespective of treatment

The significance of neurological soft signs (NSS) in major depressive disorder (MDD) remains unclear and the stability of NSS in relation to antidepressant treatment has never been investigated. We hypothesized that NSS are relatively stable trait markers of MDD. We thus predicted that patients show more NSS than healthy controls, irrespective of illness duration and antidepressant treatment. To test this hypothesis, NSS were assessed in chronically depressed, medicated MDD patients before (n = 23) and after (n = 18) a series of electroconvulsive therapy (ECT). In addition, NSS were assessed once in acutely depressed, unmedicated MDD patients (n = 16) and healthy controls (n = 20). We found that both chronically depressed, medicated MDD patients and acutely depressed, unmedicated MDD patients showed more NSS than healthy controls. The degree of NSS in both patient groups did not differ. Importantly, we found no change in NSS after on average eleven sessions of ECT. Thus, the manifestation of NSS in MDD seems to be independent of illness duration and pharmacological and electroconvulsive antidepressant treatment. From a clinical perspective, our findings corroborate the neurological safety of ECT.

Automated summary

The significance of neurological soft signs (NSS) in major depressive disorder (MDD) is unclear, and no research has been conducted on the stability of NSS in relation to antidepressant treatment. This study aimed to investigate whether NSS are stable trait markers of MDD and to test the hypothesis that MDD patients show more NSS than healthy controls, regardless of illness duration and antidepressant treatment. The findings showed that both chronically depressed, medicated MDD patients and acutely depressed, unmedicated MDD patients exhibited more NSS than healthy controls, and there was no change in NSS after a series of electroconvulsive therapy (ECT) sessions.