Healthcare consultation and sick leave before and after neck injury: a cohort study with matched population-based references

Abstract

Objectives: Recent studies based on self-assessed data on exposure and outcome suggest a negative association between poor health before neck injury and recovery. Our aim was to study actual healthcare consultation and work disability before and after neck injury (whiplash).

Design: Cohort study with matched references studied prospectively and retrospectively via regional and national held registers.

Setting: Population-based study in Region Skåne, Sweden (population=1.21 million) including all levels of healthcare.

Participants: 1443 participants aged ≥18 (54% women) with acute neck injury, Whiplash, (International Classification of Diseases-10-SE code S13.4*) in 2007 or 2008 and no such diagnosis since 1998. Each patient with a neck injury was assigned four randomly selected population references matched for age, sex and area of residence (97% of the patients and 94% of the references were followed during the whole study period).

Primary and secondary outcome measures: We studied changes in healthcare consultations 3 years before to 3 years after diagnosis as well as sick leave episodes. Analyses were also stratified by preinjury frequency of consultation.

Results: Before the injury, the mean number of total consultations over 36 months among the neck injured (n=1443) and references (n=5772) was 9.3 vs 7.2 (p<0.0001) and postneck injury 12.7 vs 7.8 (p<0.0001). In the group of high-frequent consulters, there were more women compared with frequent and low-frequent consulters (70.6% vs 32.8%; p<0.0001). Among low-frequent and frequent consulters preinjury (n=967, 67% of the cohort), 16% became high-frequent consulters attributable to the injury. The number of days of sick leave preinjury was correlated with the number of preinjury and postinjury consultations (r=0.47 (99% CI 0.38 to 0.49), r=0.32 (99% CI 0.25 to 0.37)).

Conclusions: People with a neck injury constitute a heterogeneous group. The preinjury level of healthcare consultation is associated with the postinjury level of consultation.

Keywords: EPIDEMIOLOGY; Register; Treatment; Whiplash injury.

Figure 1

Flow chart of study inclusion.

Figure 2

Schematic figure over the 6-year study period; 3 years before until 3 years after neck-injury diagnosis.

Figure 3

Mean number of healthcare consultations for all types of healthcare, physican care and physiotherapist care of those with neck injury and of three different reference cohorts (see Methods section).

Figure 4

Mean number of healthcare consultations after neck injury for all types of healthcare, physican care and physiotheraphist care of those with neck injury stratified by their preinjury consultation level; low-frequent (n=384), frequent (n=583) and high-frequent (n=476).

Figure 5

Mean number of sick days (sick leave and disability pension) for those with neck injury and references (A) and by preinjury consultation level for cases; low-frequent (n=384), frequent (n=583) and high-frequent (n=476) (B).

Figure 6

Annual postinjury consultation level stratified by preinjury consultation level; low-frequent ≤1 consultation, frequent=2–8 consultations and high-frequent ≥9 consultations per year pre neck injury. Interpretation (A), proportion of those with neck injury defined as low-frequent consulter pre neck injury that was defined as low-frequent, frequent and high-frequent consulters years 1, 2 and 3 postneck injury.