Table 2 Comparison of quality of life, depression, productivity, and healthcare resource utilization across cohorts

Health-related quality of life

 SF-12 MCS, mean (SD)

44.7 (9.4)

43.4 (9.5)^*

42.0 (7.9)^***

40.4 (6.3)^***

38.4 (10.8)^***

 SF-12 PCS, mean (SD)

51.5 (8.1)

49.8 (8.0)^**

48.8 (8.5)^***

47.2 (8.3)^***

46.0 (9.7)^***

 EQ-5D utility score, mean (SD)

0.8 (0.2)

0.8 (0.2)^*

0.8 (0.2)^***

0.7 (0.2)^***

0.7 (0.3)^***

 EQ-5D VAS score, mean (SD)

73.5 (23.2)

70.8 (22.7)

65.5 (25.9)^***

63.8 (23.4)^***

52.9 (27.8)^***

Depression

 PHQ-9 score, mean (SD)

6.1 (5.8)

7.8 (6.3)^***

8.8 (6.5)^***

10.0 (5.8)^***

11.8 (7.3)^***

 PHQ-9 score segment, n(%)

  None-minimal depression (0–4)

589 (49.5)

91 (36.6)^**

56 (31.8)^***

16 (17.2)^***

13 (16.9)^***

  Mild depression (5–9)

328 (27.6)

84 (33.7)^**

53 (30.1)^***

34 (36.6)^***

20 (26.0)^***

  Moderate depression (10–14)

155 (13.0)

40 (16.1)^**

34 (19.3)^***

23 (24.7)^***

19 (24.7)^***

  Moderately severe depression (15–19)

76 (6.4)

20 (8.0)^**

18 (10.2)^***

16 (17.2)^***

11 (14.3)^***

  Severe depression (20–27)

42 (3.5)

14 (5.6)^**

15 (8.5)^***

4 (4.3)^***

14 (18.2)^***

Productivity

 Absenteeism score^b, mean (SD)

7.1 (18.1)

10.5 (20.6)^*

10.9 (19.6)^*

11.5 (16.5)

18.7 (28.2)^***

 Presenteeism score^b, mean (SD)

21.9 (27.3)

33.4 (29.3)^***

34.8 (28.4)^***

42.8 (30.2)^***

41.9 (27.7)^***

 Total work productivity impairment score^b, mean (SD)

25.5 (31.0)

38.3 (31.8)^***

40.1 (31.4)^***

46.0 (31.6)^***

49.6 (32.5)^***

 Activity impairment score, mean (SD)

25.8 (29.0)

33.3 (27.7)^***

38.1 (29.3)^***

47.4 (27.7)^***

49.7 (29.9)^***

Healthcare resource utilization

 GP visits in past 6 months^c, mean (SD)

1.5 (2.2)

1.9 (2.2)^*

2.6 (3.1)^***

2.8 (2.7)^***

3.3 (3.6)^***

 Neurologist visits in past 6 months^c, mean (SD)

0.1 (0.3)

0.1 (0.3)

0.2 (0.5)^***

0.3 (1.1)^***

0.6 (1.1)^***

 ER visits in past 6 months^c, mean (SD)

0.7 (1.6)

1.0 (1.6)^*

1.5 (2.1)^***

1.7 (2.3)^***

2.3 (4.5)^***

 Hospitalizations in past 6 months^c, mean (SD)

0.2 (2.1)

0.2 (0.9)

0.3 (0.9)

0.5 (1.3)

0.4 (0.9)