Table 5.

Risk of hospital admission for specific conditions among 4121 women in Scotland at recruitment to the RCGP Oral Contraception Study

Reason for hospital admissionb	Number of cigarettes smoked daily at recruitment	Unadjusted		Adjusteda
		HR	95% CI	HR	95% CI
First admission for any reason	<15	1.10	1.02 to 1.19	1.05	0.98 to 1.12
	≥15	1.14	1.05 to 1.24	1.08	1.01 to 1.15
	History of serious illnessc	–	–	1.41	1.31 to 1.51
	Pill statusc	–	–	0.69	0.65 to 0.73
	Parityc	–	–	0.86	0.82 to 0.89
	Social class	–	–	0.91	0.85 to 0.96
	Age	–	–	0.98	0.97 to 0.98
Infectious and parasitic diseases	<15	1.14	1.02 to 1.28	1.10	1.00 to 1.20
	≥15	1.30	1.15 to 1.46	1.21	1.10 to 1.34
Any cancer	<15	1.63	1.36 to 1.95	1.62	1.42 to 1.85
	≥15	1.89	1.56 to 2.27	1.78	1.55 to 2.04
Diabetes mellitus	<15	1.24	0.89 to 1.75	1.10	0.87 to 1.40
	≥15	1.49	1.05 to 2.11	1.25	0.98 to 1.60
Other endocrine disease	<15	1.29	1.07 to 1.55	1.26	1.10 to 1.45
	≥15	1.48	1.22 to 1.80	1.46	1.27 to 1.69
Mental health problems	<15	1.70	1.28 to 2.26	1.63	1.33 to 2.00
	≥15	2.81	2.15 to 3.67	2.38	1.95 to 2.91
All circulatory disease	<15	1.16	1.03 to 1.31	1.16	1.06 to 1.27
	≥15	1.39	1.23 to 1.58	1.35	1.23 to 1.49
Ischaemic heart disease	<15	1.53	1.24 to 1.89	1.54	1.32 to 1.80
	≥15	2.08	1.69 to 2.57	1.91	1.63 to 2.23
Other heart disease	<15	1.25	0.97 to 1.61	1.35	1.12 to 1.62
	≥15	1.99	1.56 to 2.53	2.07	1.74 to 2.47
Cerebrovascular disease	<15	1.38	0.97 to 1.95	1.22	0.94 to 1.58
	≥15	2.04	1.45 to 2.85	2.05	1.61 to 2.61
Other circulatory disease	<15	1.05	0.91 to 1.21	1.20	0.92 to 1.13
	≥15	1.28	1.11 to 1.48	1.24	1.12 to 1.38
Respiratory disease	<15	1.57	1.32 to 1.87	1.50	1.32 to 1.70
	≥15	2.27	1.92 to 2.69	2.07	1.83 to 2.34
Digestive disease	<15	1.15	1.02 to 1.29	1.14	1.04 to 1.25
	≥15	1.31	1.16 to 1.48	1.27	1.16 to 1.39
Genitourinary disease	<15	1.06	0.96 to 1.18	1.05	0.97 to 1.14
	≥15	0.97	0.87 to 1.09	0.95	0.87 to 1.03
Other conditions not specified	<15	1.14	1.05 to 1.24	1.11	1.04 to 1.19
	≥15	1.18	1.08 to 1.29	1.15	1.07 to 1.23

^aAdjusted for age and social class at recruitment and history of serious illness, contraceptive pill use status, and parity.

^bThe number of women admitted in each category is shown in Table 4.

^cEntered as a time-dependent covariate. HR = hazard ratio.