Table 3 Association between S1P (tertiles) and cognitive impairment, expressed as odds ratios (OR) and 95% confidence intervals (CI)

 1st tertile

1.63 (0.79–3.38)

2.24 (0.85–5.89)

6.12 (1.20–31.33)

 2nd tertile

1.18 (0.59–2.37)

1.74 (0.69–4.39)

8.19 (1.41–47.56)

 3rd tertile

1

1

1

 1st tertile

1

1

1

 2nd tertile

1.10 (0.54–2.22)

1.14 (0.45–2.88)

0.94 (0.23–3.84)

 3rd tertile

1.28 (0.63–2.63)

2.64 (0.97–7.16)

3.78 (0.95–14.99)

 1st tertile

1

1

1

 2nd tertile

0.91 (0.45–1.83)

1.51 (0.57–4.01)

4.43 (0.90–21.80)

 3rd tertile

2.30 (1.07–4.94)

5.97 (2.03–17.54)

7.75 (1.53–39.28)