Combination of dextromethorphan and memantine in treating bipolar spectrum disorder: a 12-week double-blind randomized clinical trial

International Journal of Bipolar Disorders

Table 2 Within-group changes (baseline minus endpoint) in clinical characteristics of the BD-II patients in different treatment groups after 12 weeks of follow-up

Treatment groups	DM30		MM5		DM30 + MM5		Placebo
Change	Mean ± SD	P-value	Mean ± SD	P-value	Mean ± SD	P-value	Mean ± SD	P-value
Primary outcomes
HDRS	6.4 ± 4.7	< 0.001**	6.3 ± 4.9	< 0.001**	6.6 ± 4.6	< 0.001**	5.0 ± 4.1	< 0.001**
YMRS	4.7 ± 3.4	< 0.001**	4.6 ± 3.9	< 0.001**	4.9 ± 4.0	< 0.001**	3.6 ± 4.1	< 0.001**
Cytokines and BDNF
TNF-α (pg/ml)	0.1 ± 2.5	0.76	0.3 ± 1.8	0.09	0.3 ± 1.4	0.16	– 0.2 ± 1.6	0.87
CRP (ng/ml)	10.9 ± 1290.3	0.20	– 12.6 ± 1269.4	0.98	371.3 ± 1157.9	0.005**	20.9 ± 978.8	0.17
BDNF (ng/ml)	– 2.3 ± 8.3	0.035*	0.3 ± 7.6	0.75	– 2.2 ± 8.2	0.044*	0.09 ± 8.9	0.94
Metabolic parameters
TC (mg/dl)	− 0.1 ± 28.7	0.98	0.5 ± 24.5	0.90	0.6 ± 28.6	0.89	8.3 ± 24.6	0.034*
HDL-C (mg/dl)	1.6 ± 10.2	0.28	2.4 ± 8.7	0.10	− 10.7 ± 82.4	0.41	1.3 ± 7.2	0.26
LDL-C (mg/dl)	− 0.9 ± 23.1	0.79	2.6 ± 22.0	0.48	4.6 ± 24.4	0.23	7.7 ± 21.9	0.034*
Triglycerides (mg/dl)	− 11.6 ± 168.4	0.68	− 10.7 ± 38.7	0.17	− 2.5 ± 44.3	0.73	− 14.0 ± 57.0	0.20
FBS (mg/dl)	9.0 ± 38.1	0.10	− 3.3 ± 22.6	0.33	2.8 ± 9.9	0.06	2.0 ± 14.2	0.34

The difference between baseline and endpoint after 12 weeks of follow-up analyzed using a paired sample t-test
SD standard deviation, HDRS 17-item Hamilton Depression Rating Scale, YMRS Young Mania Rating Scale, TNF-α tumor necrosis factor α, CRP C-reactive protein, BDNF brain-derived neurotrophic factor, TC total cholesterol, HDL-C high-density lipoprotein-cholesterol, LDL-C low-density lipoprotein-cholesterol, DM30 dextromethorphan (30 mg/day), MM5 memantine (5 mg/day), DM30 + MM5 dextromethorphan (30 mg/day) combined with memantine (5 mg/day), FBS fasting blood sugar
*P < 0.05; **P < 0.01