Cause-specific excess mortality after hip fracture: the Norwegian Epidemiologic Osteoporosis Studies (NOREPOS)

Kristin Holvik; Christian Lycke Ellingsen; Siri Marie Solbakken; Trine Elisabeth Finnes; Ove Talsnes; Guri Grimnes; Grethe S Tell; Anne-Johanne Søgaard; Haakon E Meyer

doi:10.1186/s12877-023-03910-5

Cause-specific excess mortality after hip fracture: the Norwegian Epidemiologic Osteoporosis Studies (NOREPOS)

BMC Geriatr. 2023 Mar 31;23(1):201. doi: 10.1186/s12877-023-03910-5.

Authors

Kristin Holvik¹, Christian Lycke Ellingsen^{2

3}, Siri Marie Solbakken⁴, Trine Elisabeth Finnes^{5

6}, Ove Talsnes^{6

7}, Guri Grimnes^{8

9}, Grethe S Tell³, Anne-Johanne Søgaard⁴, Haakon E Meyer^{4

10}

Affiliations

¹ Department of Physical Health and Ageing, Norwegian Institute of Public Health, P. O. Box 222, Skøyen, Oslo, 0213, Norway. kristin.holvik@fhi.no.
² Department of Pathology, Stavanger University Hospital, Stavanger, Norway.
³ Department of Global Public Health and Primary Care, University of Bergen, Bergen, Norway.
⁴ Department of Physical Health and Ageing, Norwegian Institute of Public Health, P. O. Box 222, Skøyen, Oslo, 0213, Norway.
⁵ Department of Endocrinology, Innlandet Hospital Trust, Hamar, Norway.
⁶ Department of Endocrinology, Oslo University Hospital, Oslo, Norway.
⁷ Department of Orthopedics, Innlandet Hospital Trust, Elverum, Norway.
⁸ Department of Clinical Medicine, UiT The Arctic University of Norway, Tromsø, Norway.
⁹ Division of Internal Medicine, University Hospital of North Norway, Tromsø, Norway.
¹⁰ Department of Community Medicine and Global Health, University of Oslo, Oslo, Norway.

Abstract

Background: Information on cause of death may help appraise the degree to which the high excess mortality after hip fracture reflects pre-existing comorbidities or the injury itself. We aimed to describe causes of death and cause-specific excess mortality through the first year after hip fracture.

Methods: For studying the distribution of causes of death by time after hip fracture, we calculated age-adjusted cause-specific mortality at 1, 3, 6 and 12 months in patients hospitalized with hip fracture in Norway 1999-2016. Underlying causes of death were obtained from the Norwegian Cause of Death Registry and grouped by the European Shortlist for Causes of Death. For estimating excess mortality, we performed flexible parametric survival analyses comparing mortality hazard in patients with hip fracture (2002-2017) with that of age- and sex matched controls drawn from the Population and Housing Census 2001.

Results: Of 146,132 Norwegians with a first hip fracture, a total of 35,498 (24.3%) died within one year. By 30 days post-fracture, external causes (mainly the fall causing the fracture) were the underlying cause for 53.8% of deaths, followed by circulatory diseases (19.8%), neoplasms (9.4%), respiratory diseases (5.7%), mental and behavioural disorders (2.0%) and diseases of the nervous system (1.3%). By one-year post-fracture, external causes and circulatory diseases together accounted for approximately half of deaths (26.1% and 27.0%, respectively). In the period 2002-2017, cause-specific one-year relative mortality hazard in hip fracture patients vs. population controls ranged from 1.5 for circulatory diseases to 2.5 for diseases of the nervous system in women, and correspondingly, from 2.4 to 5.3 in men.

Conclusions: Hip fractures entail high excess mortality from all major causes of death. However, the traumatic injury of a hip fracture is the most frequently reported underlying cause of death among older patients who survive less than one year after their fracture.

Keywords: Causes of death; Excess mortality; Hip fracture; Norway; Registry-based epidemiology.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Cardiovascular Diseases* / epidemiology
Comorbidity
Female
Hip Fractures* / epidemiology
Humans
Male
Norway / epidemiology
Osteoporosis* / epidemiology
Risk Factors