Table 3 Occurrence of epilepsy in people admitted with multiple sclerosis, and of multiple sclerosis in people admitted with epilepsy: observed (O) and expected number (E) of cases in each cohort, relative risk (RR) ^a in the exposure cohort compared with the control cohort ^b , with its 95% confidence intervals (95% CI), and p values, by age group

Multiple sclerosis

<35

Epilepsy

30

3.8

8.0 (5.34–11.39)

<0.001

358

99.3

3.7 (3.28–4.05)

<0.001

35–44

15

3.6

4.2 (2.35–7.07)

<0.001

587

159.0

3.9 (3.59–4.26)

<0.001

45–54

11

3.3

3.4 (1.66–6.11)

<0.001

780

237.0

3.6 (3.34–3.87)

<0.001

55–64

4

1.9

2.1 (0.57–5.46)

0.247

508

173.0

3.1 (2.81–3.37)

<0.001

65–74

1

2.0

0.5 (0.01–2.81)

0.728

253

98.2

2.6 (2.31–2.98)

<0.001

75+

1

0.6

1.7 (0.04–9.34)

0.894

94

52.0

1.8 (1.46–2.22)

<0.001

Total

62

15.3

4.1 (3.14–5.27)

<0.001

2580

809.7

3.3 (3.14–3.40)

<0.001

Epilepsy

<35

Multiple sclerosis

10

6.3

1.6 (0.76–2.98)

0.203

176

79.6

2.4 (2.01–2.77)

<0.001

35–44

8

2.6

3.2 (1.37–6.52)

0.002

202

96.2

2.2 (1.92–2.59)

<0.001

45–54

9

2.3

4.2 (1.87–8.25)

<0.001

214

111

2.1 (1.77–2.36)

<0.001

55–64

3

1.8

1.7 (0.35–5.32)

0.569

110

81.3

1.4 (1.13–1.68)

<0.001

65–74

3

0.5

6.8 (1.23–24.57)

0.006

83

48.2

1.8 (1.41–2.23)

<0.001

75+

0

0

40

33.6

1.2 (0.85–1.66)

0.298

Total

33

13.6

2.5 (1.71–3.54)

<0.001

825

450.4

1.9 (1.79–2.07)

<0.001