The Laboratory Diagnosis Of Depression - The Circadian Rhythm Of The Biological Markers

Objective To explore the related neurobiochemistry or neuroendocrine signs in depressive patients with or without diurnal mood variation.Methods (1) Cases Investigation: the monthly composing ratio of discharge frequency in total, between genders, and between patients with mood disorder and patients with non-mood disorder who discharged from unitary-nursing care wards in Nanjing Brain Hospital from March 2006 to February 2008. We selected those patients who had at least two hospitalizations in our hospital and once hospitalization being in the two years above and diagnosed as mood disorder finally. Further more, their initial diagnosis must be depression, including single episode depression and recurrent depression. The aim of this study is to find whether or not diurnal mood variation would influence on the final diagnosis. (2) Clinical Research: The plasma level of melatonin(MLT), beta-endorphin(β-EP) and neuropeptide Y(NPY) were measured at 6:30 and 16:30 in a diel in depressive patients, including 18 patients without diurnal mood variation and 36 patients with diurnal mood variation and normal controls (n=40).Results (1) Cases Investigation: There was a significant difference in composition ratio of frequency in genders between non-mood disorder group and mood disorder group (P<0.05). For male depressive patients, the monthly composing ratio of discharge frequency showed differences between counterpart months in the consecutive two-year period (P<0.05). The patients whose initial diagnosis was depression and had characteristic symptoms of diurnal mood variation in their first hospitalization will have more chance to be diagnosed as major depressive disorder other than bipolar disorder (P<0.05). (2) Clinical Research: Compared with controlled group, the plasma level of melatonin at 6:30 and the differences between the two points were higher and lower for patient group with diurnal mood variation, respectively (P<0.05 and P<0.05) . The difference of the plasma level of melatonin between the two points was positively correlated to the factor score of recognition disturbance of Hamilton rating scale for depression (HAMD) (P<0.05). There was a significantly positive relationship between the plasma level of beta-endorphin at 6:30 and the factor score of recognition disturbance of HAMD for the whole patients group (P<0.05). The plasma level of neuropeptide at 16:30 was negatively correlated to the factor score of weight decrease of HAMD (P<0.05) for patient group without diurnal mood variation.Conclusion The patients whose initial diagnosis was depression and had characteristic symptoms of diurnal mood variation in their first hospitalization will have more chance to be diagnosed as major depressive disorder other than bipolar disorder, and the plasma level of melatonin may be correlated to the diurnal mood variation for patients with depression.