The impact of low back pain on work: a study in primary care consulters.

Background: The cost of low back pain (LBP) to employers is high, with an estimated pound 9090 million lost in the United Kingdom in 1998. Economic analysis of LBP has focused on work absence among the employed. There is little research characterising individuals who report reduced duties or who are not in employment because of LBP.
Aims: To compare the health related characteristics of primary care LBP consulters reporting usual employment, reduced duties, sick leave and non-employment as a result of LBP.
Methods: Prospective cohort study recruiting LBP consulters aged 30-59 years of age from five general practices in North Staffordshire.
Results: Nine hundred and thirty-five participants completed the baseline phase, 65% were in employment and 35% were not in employment. Of the employed participants over 1 in 10 (11%) were undertaking reduced duties and almost one-fifth were reporting sick leave (22%). Furthermore, 37% of non-employed consulters reported that LBP was the reason for non-employment. Significant differences at baseline in socioeconomic status, self-rated health, anxiety, depression and disability were found between those undertaking their usual job, those on reduced duties and those on sickness absence due to LBP, with those participants further removed from the work force reporting worse health across all measures. Significant differences were also found in self-rated health between those not working due to LBP and those not working for other reasons, with participants not working due to LBP reporting worse self-rated health. At follow-up, work status was found to be relatively stable.
Conclusion: These findings indicate that the economic impact of LBP may be higher than previously estimated when data on reduced duties is combined with work absence. The additional impact of unemployment due to LBP should also be included in future assessments of the impact of LBP on the workforce.