Table 1 Descriptive statistics for CSO-PVS and BG-PVS volumes (in ml) for four annual visits, stratified by clinical groups. Group-level results included subjects who had at least three scans available (n = 503). We removed extreme values in volumes within the whole sample for each time point to lessen the influence of outliers and corrected estimates for age at the time of the scan

Baseline demographics

Females (%)

52.12

40.85

54.84

Age (years)

70.2 ± 0.28

72.5 ± 0.69

74.3 ± 1.12

Education (years)

14.9 ± 0.15

14.0 ± 0.37

12.9 ± 0.50

Baseline volume (ml)

CSO-PVS

1.91 ± 0.08

2.02 ± 0.20

1.56 ± 0.30

BG-PVS

0.54 ± 0.02

0.60 ± 0.04

0.42 ± 0.06

12-month follow-up volume (ml)

CSO-PVS

2.06 ± 0.09

2.02 ± 0.21

1.81 ± 0.32

BG-PVS

0.57 ± 0.02

0.59 ± 0.04

0.44 ± 0.06

24-month follow-up volume (ml)

CSO-PVS

1.99 ± 0.09

2.28 ± 0.21

1.84 ± 0.33

BG-PVS

0.58 ± 0.02

0.63 ± 0.04

0.46 ± 0.06

36-month follow-up volume (ml)

CSO-PVS

2.07 ± 0.11

2.21 ± 0.26

1.66 ± 0.49

BG-PVS

0.57 ± 0.02

0.62 ± 0.05

0.42 ± 0.09

Annual change^a of PVS (in ml/year)

CSO-PVS

0.04 ± 0.03

0.08 ± 0.04

0.03 ± 0.07

BG-PVS

0.01 ± 0.00

0.01 ± 0.01

0.002 ± 0.01

Annual change^a of PVS from baseline (in %/year)

CSO-PVS

2.11

4.13

1.98

BG-PVS

1.82

1.68

0.46