Elevated serum growth differentiation factor 15 in multiple system atrophy patients: A case control study

Table 1 Clinical characteristics of multiple system atrophy patients, Parkinson disease patients and controls

	MSA	PD	Control	P value
All
Subjects, n	49	50	50	-
Age, yr	61.7 ± 7.7	61.4 ± 7.5	58.5 ± 7.5	0.077
Female/male, n	26/23	26/24	30/20	0.683
Age of onset, yr	58.7 ± 7.4	56.6 ± 7.1	-
MSA-P/MSA-C, n	30/20	-	-	-
Probable/Possible, n	31/18	-	-	-
Clinical rate scales (UMSARSII/UPDRSIII)	19.5 ± 6.4 (UMSARSII)	26.1 ± 13.2 (UPDRSIII)	- -	-
GDF15, pg/mL	1105.69 (984.24)	506.70 (346.80)	313.85 (247.76)	0.000

MSA: Multiple system atrophy; MSA-P: Multiple system atrophy-parkinsonian type; MSA-C: Multiple system atrophy-cerebellar type; PD: Parkinson disease; GDF15: Growth differentiation factor 15.

Table 2 Serum levels of growth differentiation factor 15 in different subgroups of multiple system atrophy

Subgroups	GDF15, pg/mL	P value
Age of onset
> 50 yr	1156.99 (1028.41)	0.185
≤ 50 yr	795.32 (605.42)
Gender
Female	795.31 (698.54)	0.043
Male	1311.84 (1214.16)
Clinical subtype
MSA-P	1121.82 (897.09)	0.622
MSA-C	916.14 (1009.59)
Diagnosis criteria
Probable	887.55 (1004.50)	0.561
Possible	1182.16 (753.32)
Duration
> 3 yr	1393.79 (1021.36)	0.000
≤ 3 yr	612.31 (527.96)

GDF15: Growth differentiation factor 15; MSA-P: Multiple system atrophy-parkinsonian type; MSA-C: Multiple system atrophy-cerebellar type.

Table 3 Receiver-operating characteristic curve analysis of serum growth differentiation factor 15 levels as a potential multiple system atrophy diagnostic biomarker

Group	Subtype	AUC	SE	95%CI	P value	Cutoff, pg/mL	Sensitivity, %	Specificity, %
MSA vs Control	Overall	0.929	0.027	0.876-0.981	0.000	470.42	85.7	88.0
	Male	0.954	0.030	0.896-1.000	0.000	552.10	82.6	100.0
	Female	0.905	0.044	0.820-0.990	0.000	470.42	80.8	90.0
MSA vs PD	Overall	0.765	0.048	0.671-0.859	0.000	1075.91	51.0	96.0
	Male	0.772	0.072	0.630-0.914	0.001	1075.91	65.2	95.8
	Female	0.783	0.066	0.654-0.911	0.000	616.39	65.4	88.5

MSA: Multiple system atrophy; PD: Parkinson disease; AUC: Area under the receiver-operating characteristic curve.