Table 1 Demographic information for each cohort at baseline

Study number

1

2

3

4

5

6

Number of participants

140

154

144

188

280

201

1107

Age at PD diagnosis (years)

70.34

(9.56)

(37.00–89.60)

65.88 (10.38)

(34.80–87.10)

71.20 (9.88) (39.80–90.00)

67.69 (9.20) (42.10–85.30)

68.43 (9.64) (40.35–96.36)

72.12 (10.35) (37.00–91.00)

69.22 (10.02) (34.80–96.36)

Sex (% male)

55.70

64.90

59.70

61.20

62.10

61.20

61.10

Years of education (years)

11.38

(3.72)

(8.00–33.00)

12.77 (3.81) (3.00–24.00)

9.82 (3.79) (6.00–20.00)

11.14 (3.28) (6.00–19.00)

12.31 (3.10) (5.00–22.00)

12.37 (2.77) (9.00–21.00)

11.76 (3.47) (3.00–33.00)

LEDD (mg)

174.78 (242.85)

(0.00–1040.00)

178.04 (148.16) (0.00–880.00)

10.76 (49.53) (0.00–300.00)

2.81 (27.35) (0.00–300.00)

137.26 (157.49) (0.00–700.00)

19.70 (76.66) (0.00–400.00)

86.89 (154.16) (0.00–1040.00)

PD duration at baseline (years)

0.32

(0.44)

(0.00–2.15)

0.48 (0.39)

(0.00–2.00)

0.01 (0.12)

(0.00–1.54)

0.14 (0.14) (0.00–1.03)

0.24 (0.32)

(0.00–2.35)

0.01 (0.05) (0.00–0.59)

0.19 (0.32)

(0.00–2.35)

Follow-up duration-diagnosis to last visit (years)

5.86

(3.08)

(0.00–10.40)

3.90 (1.66) (0.14–6.46)

6.82 (3.14) (0.00–10.28)

6.36 (1.76) (0.07–8.09)

3.91 (2.66) (0.00–9.46)

7.03 (3.89) (0.00–16.97)

5.50 (3.12) (0.00–16.97)

Beta-blocker users at baseline (%)

15.00

18.20

30.60

10.60

13.60

21.90

17.60

Beta-agonist users at baseline (%)

5.70

9.70

6.90

5.30

3.90

7.00

6.10

Beta-blocker and beta-agonist users at baseline (%)

0.00

0.00

2.10

(n = 3)

0.50

(n = 1)

0.00

0.00

0.40 (n = 4)

MDS-UPDRS Part III score

33.85 (14.80)

(7.10–74.90)

26.90 (12.09) (7.00–69.00)

34.9 (13.9) (8.30–75.70)

30.19

(13.34) (7.10–74.60)

30.64 (11.96) (5.00–67.00)

32.12 (13.64) (5.90–77.90)

31.27 (13.36) (5.00–77.90)

H&Y stage

1.98

(0.68)

(1.00–4.00)

1.98 (0.67) (1.00–4.00)

2.29 (0.71) (1.00–5.00)

1.90 (0.64) (1.00–4.00)

1.79

(0.72) (1.00–5.00)

2.27 (0.84) (1.00–5.00)

2.01 (0.74) (1.00–5.00)

H&Y ≥ 3 at baseline (%)

10.00

12.30

19.40

9.00

12.10

22.90

14.40

MMSE

27.94

(1.54)

(24.00–30.00)

28.63 (1.31) (24.00–30.00)

28.46 (1.72) (18.00–30.00)

27.85 (2.14) (21.00–30.00)

28.68 (1.39) (22.00–30.00)

28.12 (2.39) (15.00–30.00)

28.30 (1.82) (15.00–30.00)

CIRS System Score

2.32

(1.45)

(0.00–7.00)

2.57 (1.66)

(0.00–7.00)

Not Available

Not Available

2.25

(1.46) (0.00–7.00)

3.60 (1.85) (0.00–9.00)

2.68 (1.71) (0.00–9.00)

Cardiovascular disease (%)

49.30

44.20

54.20

44.70

49.30

58.20

50.00

Autoimmune/ Inflammatory disease (%)

17.10

18.80

Not Available

Not Available

25.00

21.90

21.50

Diabetes (%)

6.40

8.40

5.60

6.40

9.30

10.00

7.90

Smoking status (Ex or current) (%)

57.90

43.80

33.80

49.50

50.20

45.80

47.20