RELATIONSHIP BETWEEN THE NEWCASTLE SCALE AND SLEEP POLYSOMNOGRAPHIC VARIABLES IN MAJOR DEPRESSION - A CONTROLLED-STUDY

In order to investigate the reliability of the endogenous concept of d epressive illness with some sleep EEG parameters, we studied 39 male i npatients suffering from a nonbipolar major depressive episode (15 end ogenous (MDDE) and 24 nonendogenous (MDDNE)) and 20 age and sex matche d normal controls (C). All patients were diagnosed according to the Re search Diagnostic Criteria (RDC) and the endogenous character of the e pisode was assessed with the Newcastle Endogenous Depression Diagnosti c Index. We found significant differences for the following variables between the three groups (MDDE, MDDNE and C): sleep period time (SPT), REM latency, stage II, slow wave sleep (SWS), REM latency expressed a s a continuous variable and REM latency expressed as a dichotomizing v ariable with a threshold of 50 min. These variables were used to compa re the endogenous and the nonendogenous depressed patients and also th e major depressed patients and the normal controls. Significant differ ences were observed between all depressed patients and control subject s for amount of SWS and REM latency which were both reduced in endogen ous and nonendogenous depressed patients. No significant difference wa s observed between endogenous and nonendogenous depressed patients, ex cept for the REM latency expressed with a threshold of 50 min (more fr equently observed in endogenous depressed patients). Our data support the observation that SWS and REM latency are decreased in major depres sive patients. However, in this age and sex controlled study, subtypin g nonbipolar major depressive disorder for an endogenous character by the Newcastle Endogenous Depression Diagnostic Index (NEDDI) did not r eveal further significant differences for sleep EEG variables, except for the shortening of the REM latency expressed as a dichotomizing var iable.