Are risk factors for atherothrombotic disease associated with back pain sickness absence? The Whitehall II study

Study objective-To explore the previously stated hypothesis that risk facto rs for atherothrombotic disease are associated with back pain. Design-Prospective (mean of four years of follow up) and retrospective anal yses using two main outcome measures: (a) short (less than or equal to 7 da ys) and long (> 7 days) spells of sickness absence because of back pain rep orted separately in men and women; (b) consistency of effect across the res ulting four duration of spell and sex cells. Setting-14 civil service departments in London Participants-3506 male and 1380 female white office-based civil servants, a ged 35-55 years at baseline. Main results-In age adjusted models, low apo Al was associated with back pa in across all four duration-sex cells and smoking was associated across thr ee cells. Six factors were associated with back pain in two cells: low exer cise and high BMI, waist-hip ratio, triglycerides, insulin and Lp(a). On fu ll adjustment (for age, BMI, employment grade and back pain at baseline), e ach of these factors retained a statistically significant effect in at leas t one duration-sex cell. Triglycerides were associated with short and long spells of sickness absence because of back pain in men in fully adjusted mo dels with rate ratios (95% confidence intervals) of 1.53 (1.1, 2.1) and 1.7 5 (1.0, 3.2) respectively. There was little or no evidence of association i n age adjusted models with: fibrinogen, glucose tolerance, total cholestero l, apoB, hypertension, factor VII, von Willebrand factor, electrocardiograp hic evidence of coronary heart disease and reported angina. Conclusions-In this population of office workers, only modest support was f ound for an atherothrombotic component to back pain sickness absence. Howev er, the young age of participants at baseline and the lack of distinction b etween different types of back pain are likely to bias the findings toward null. Further research is required to ascertain whether a population sub-gr oup of atherothrombotic back pain can be atherothrombotic identified.