Meta-analysis of dopaminergic-serotonergic modulation strategies for depressive symptoms in Parkinson’s disease

Table 1 Risk assessment and quality evaluation of literature bias

Ref.	Type	Random sequence generation	Distribution concealment	Blind implementation	Missing data	Selective reporting	Risk type of bias	Risk score (0-10)	Quality score (Jadad)
Barone et al[10], 2010	RCT	+	+	+	+	+	Low risk	9	5
Menza et al[11], 2009	RCT	?	?	-	?	?	Moderate risk	5	3
Rektorova et al[12], 2008	RCT	-	-	-	-	-	High-risk	2	2
Weintraub et al[13], 2010	RCT	?	?	-	?	?	Moderate risk	5	3
Devos et al[14], 2008	RCT	+	+	+	+	?	Low risk	8	5

According to the specific performance in the study, each risk factor was divided into low risk (“+”), high risk (“-”) and unclear (“?”). RCT: Randomized controlled trial.

Table 2 Baseline data of patients included in the literature, n (%)/mean ± SD

Ref.	n	Age (years)	Male	Course of disease (year)	UPDRS-III (points)	HAMD-17 (points)	Depression score (points)	Dopaminergic drug	SSRI (intervention group)	MMSE (points)
Barone et al[10], 2010	323	64.30 ± 9.10	181 (56.04)	6.20 ± 4.50	28.50 ± 12.30	19.80 ± 4.20	-	Pramipexole (experimental drug), levodopa utilization approximately 93% at baseline	None (compared to placebo)	28.10 ± 1.50
Menza et al[11], 2009	52	65.10 ± 8.70	30 (57.69)	7.00 ± 5.10	30.20 ± 13.50	20.50 ± 4.80	-	Baseline dose not reported in detail	Paroxetine (mean dose: 27.70 mg/day)	28.50 ± 1.20
Rektorova et al[12], 2008	30	63.50 ± 7.80	17 (56.67)	5.80 ± 3.90	27.80 ± 11.60	-	MADRS: 21.60 ± 4.10	Ropinirole (experimental drug, flexible dose)	None (compared to pramipexole)	28.30 ± 1.40
Weintraub et al[13], 2010	55	66.20 ± 9.30	34 (61.82)	7.50 ± 4.80	31.00 ± 14.10	-	MADRS: 22.90 ± 5.20	Baseline dose not reported in detail	None (atorvastatin compared to placebo)	27.80 ± 1.80
Devos et al[14], 2008	48	64.80 ± 8.50	28 (58.33)	6.50 ± 4.20	29.50 ± 12.80	19.50 ± 4.50	-	Levodopa (mean dose: 568.75 mg/day)	Citalopram (mean dose: 25.83 mg/day)	28.00 ± 1.60

UPDRS-III: Unified Parkinson’s Disease Rating Scale Part III; HAMD-17: Hamilton Depression Rating Scale; SSRI: Selective serotonin reuptake inhibitor; MMSE: Mini-Mental State Examination; MADRS: Montgomery-Asberg Depression Rating Scale.

Table 3 Summary effect sizes and heterogeneity analysis of each major outcome indicator

Reproductive outcomes	Number of studies	WMD/RR 95%CI	P value	I2
Improving depression	3	1.35 (1.15-1.60)	< 0.001	0%
Quality of life	2	-2.41 (-3.02 to -1.79)	< 0.001	0%
Motor function	4	-0.75 (-0.91 to -0.59)	< 0.001	80.9%
Adverse event	5	1.61 (0.82-3.19)	0.169	0%

WMD: Weighted mean difference; RR: Relative risk; CI: Confidence interval.