What is the impact of underweight on self-reported health trajectories and mortality rates: a cohort study

Table 4 Mortality rates and hazard ratio for all-cause mortality between categories of body mass index in the Tromsø study 1986-2008 until end of follow up on December 31, 2015

	Person Time (Years)	Died	Mortality rate	Hazard ratio ^a	95% CI
Body mass index
< 18.5 Kg/m²	5121	109	0.021	1.69	(1.38- 2.06)
18.5-22.99 Kg/m²	129,676	1122	0.009	1.14	(1.05- 1.25)
23-24.99 kg/m² (ref)	107,253	1026	0.010	1.00	Reference
25-29.99 kg/m²	169,612	2160	0.013	0.97	(0.90- 1.05)
> 30 kg/m²	46,709	855	0.018	1.12	(1.02- 1.23)
Self-Reported Health
Poor	10,762	416	0.039	2.54	(1.88- 3.45)
Not so good	117,369	2581	0.022	1.94	(1.55- 2.43)
Good	259,293	2045	0.008	1.30	(1.10- 1.54)
Very good (ref)	70,947	230	0.003	1.00	Reference
Time varying covariates
Self-Reported Health				0.004	(1.00- 1.02)

^aHazard ratios (HR) are based on Cox proportional hazard and includes both SRH and BMI controlled for age, gender, comorbidity, mental health symptoms, systolic blood pressure, cholesterol, physical activity levels and daily smoking. For HRs shown in Table 4, is SRH time-varying but BMI time-invariant

ISSN: 1477-7525