Table 2.

Factors associated with insomnia: results of multivariate analysis

	B	OR	95% CI	P
Sex (reference: male)
Female*	0.423	1.526	1.297–1.796	< 0.001
Age (years) (reference: 20–29)
30–39	0.046	1.047	0.765–1.433	0.773
40–49	0.059	1.061	0.829–1.358	0.638
50–59	− 0.185	0.831	0.659–1.049	0.119
60–69	− 0.030	0.971	0.748–1.259	0.822
Marital status (reference: married)
Unmarried*	0.228	1.256	1.007–1.566	0.043
Divorced/widowed	− 0.032	0.968	0.678–1.382	0.859
Working pattern (reference: day work)
Shift work	0.322	1.380	0.829–2.299	0.216
Night work*	0.445	1.561	1.160–2.101	0.003
Monthly income (USD; reference: < 1600)
< 1600	0.011	1.011	0.726–1.409	0.946
1600–2399	− 0.199	0.820	0.583–1.154	0.254
2400–3199	− 0.298	0.742	0.523–1.053	0.095
3200–3999	− 0.239	0.788	0.545–1.138	0.203
4000–4799	− 0.123	0.884	0.601–1.301	0.532
4800–5599	− 0.261	0.770	0.547–1.083	0.133
Alcohol consumption (reference: non-alcoholics)	− 0.276	0.759	0.555–1.037	0.083
Smoking (reference: non-smoker)*	0.237	1.267	1.011–1.587	0.04

CI confidence interval, OR odds ratio, USD United States dollar

*p < 0.05