Post-injury long-term sickness absence and risk of disability pension: The role of socioeconomic status

Eyvind Ohm; Christian Madsen; Hans Magne Gravseth; Søren Brage; Else Karin Grøholt; Kari Alver; Kristin Holvik

doi:10.1016/j.injury.2024.111480

Post-injury long-term sickness absence and risk of disability pension: The role of socioeconomic status

Injury. 2024 Apr;55(4):111480. doi: 10.1016/j.injury.2024.111480. Epub 2024 Feb 28.

Authors

Eyvind Ohm¹, Christian Madsen², Hans Magne Gravseth³, Søren Brage⁴, Else Karin Grøholt⁵, Kari Alver⁵, Kristin Holvik⁶

Affiliations

¹ Department of Health and Inequality, Norwegian Institute of Public Health, PO Box 222 Skøyen 0213 Oslo, Norway. Electronic address: Eyvind.Ohm@fhi.no.
² Department of Disease Burden, Norwegian Institute of Public Health, Zander Kaaesgt. 7 5015 Bergen, Norway.
³ Department of Occupational Health Surveillance, National Institute of Occupational Health, PO Box 5330 Majorstuen 0304 Oslo, Norway.
⁴ Retired medical doctor with a PhD in epidemiology/social medicine. Before retirement SB held a position in the Norwegian Labour and Welfare Administration, leading the unit responsible for medical coding of welfare benefits from 1998 to 2015.
⁵ Department of Health and Inequality, Norwegian Institute of Public Health, PO Box 222 Skøyen 0213 Oslo, Norway.
⁶ Department of Physical Health and Ageing, Norwegian Institute of Public Health, PO Box 222 Skøyen 0213 Oslo, Norway.

PMID: 38452702
DOI: 10.1016/j.injury.2024.111480

Abstract

Introduction: Previous research has identified low socioeconomic status (SES) as a risk factor for long-term sickness absence (LTSA) and disability pension (DP) following trauma. However, most studies lack information on medical diagnoses, limiting our understanding of the underlying factors. To address this gap, we retrieved information about diagnostic causes for receipt of welfare benefits to explore the role of SES in the transition from post-injury LTSA to permanent DP among the working population in Norway.

Materials and methods: We conducted a population-based cohort study of all Norwegian residents aged 25-59 years registered with a spell of LTSA due to injury commencing in the period 2000-2003. This cohort was followed through 2014 by linking information on receipt of welfare benefits with sociodemographic data from administrative registers. SES was defined as a composite measure of educational attainment and income level. We used flexible parametric survival models to estimate hazard ratios (HR) with 95 % confidence intervals (CI) for all-cause and diagnosis-specific DP according to SES, adjusting for sex, age, marital status, immigrant status and healthcare region of residence.

Results: Of 53,937 adults with post-injury LTSA, 9,665 (18 %) transferred to DP during follow-up. The crude risk of DP was highest for LTSA spells due to poisoning and head injuries. Overall, individuals in the lowest SES category had twice the risk of DP compared to those in the highest SES category (HR = 2.25, 95 % CI 2.13-2.38). The difference by SES was greatest for LTSA due to poisoning and smallest for LTSA due to head injuries. A majority (75 %) of DP recipients had a non-injury diagnosis as the primary cause of DP. The socioeconomic gradient was more pronounced for non-injury causes of DP (HR = 2.47, 95 % CI 2.31-2.63) than for injury causes (HR = 1.73, 95 % CI 1.56-1.92) and was especially steep for DP due to musculoskeletal diseases and mental and behavioural disorders.

Conclusions: The relationship between SES and DP varied by both the type of injury that caused LTSA and the diagnosis used to grant DP, highlighting the importance of taking diagnostic information into account when investigating long-term consequences of injuries.

Keywords: Data linkage; Diagnosis; Disability; Injuries; Register-based research; Sick leave; Socioeconomic factors.

MeSH terms

Adult
Cohort Studies
Craniocerebral Trauma*
Disabled Persons*
Humans
Pensions
Prospective Studies
Risk Factors
Sick Leave
Social Class