Table 2 Influence of headache (related to type and frequency) on the risk of insomnia in HUNT-3 among the population at risk (n = 19,271)

n, total = 14,639

n = 3069

OR (95% CI)

n = 2020

OR (95% CI)

n = 1049

OR (95% CI)

No headache or CMSCs

7263

1080

1.0 (ref)

581

1.0 (ref)

499

1.0 (ref)

Headache⁴

7376

1989

1.7 (1.6 – 1.9)

1439

1.8 (1.6 – 2.0)

550

1.7 (1.4 – 1.9)

< 7 days / month

6202

1589

1.7 (1.5 – 1.8)

1142

1.7 (1.5 – 1.9)

447

1.6 (1.4 – 1.8)

≥ 7 days / month

1174

400

2.2 (1.9 – 2.6)

297

2.2 (1.8 – 2.7)

103

2.2 (1.7 – 2.8)

p-trend

<0.001

<0.001

<0.001

Non migraineous headache

4963

1278

1.7 (1.5 – 1.8)

884

1.7 (1.5 – 1.9)

394

1.6 (1.4 – 1.9)

< 7 days / month

4279

1049

1.6 (1.4 – 1.8)

726

1.6 (1.4 – 1.8)

323

1.6 (1.3 – 1.8)

≥ 7 days / month

684

229

2.2 (1.8 – 2.7)

158

2.2 (1.7 – 2.8)

71

2.3 (1.6 – 3.1)

p-trend

<0.001

<0.001

<0.001

Migraine

2413

711

1.9 (1.7 – 2.1)

555

2.0 (1.7 – 2.3)

156

1.7 (1.4 – 2.1)

< 7 days / month

1923

540

1.8 (1.6 – 2.1)

416

1.9 (1.6 – 2.2)

124

1.6 (1.3 – 2.1)

≥ 7 days / month

490

171

2.2 (1.7 – 2.7)

139

2.2 (1.7 – 2.9)

32

2.0 (1.3 – 3.1)

p –trend

<0.001

<0.001

<0.001