Predictors of Occurrence and Severity of First Time Low Back Pain Episodes: Findings from a Military Inception Cohort

Abstract

Primary prevention studies suggest that additional research on identifying risk factors predictive of low back pain (LBP) is necessary before additional interventions can be developed. In the current study we assembled a large military cohort that was initially free of LBP and followed over 2 years. The purposes of this study were to identify baseline variables from demographic, socioeconomic, general health, and psychological domains that were predictive of a) occurrence; b) time; and c) severity for first episode of self-reported LBP. Baseline and outcome measures were collected via web-based surveillance system or phone to capture monthly information over 2 years. The assembled cohort consisted of 1230 Soldiers who provided self-report data with 518 (42.1%) reporting at least one episode of LBP over 2 years. Multivariate logistic regression analysis indicated that gender, active duty status, mental and physical health scores were significant predictors of LBP. Cox regression revealed that the time to first episode of LBP was significantly shorter for Soldiers that were female, active duty, reported previous injury, and had increased BMI. Multivariate linear regression analysis investigated severity of the first episode by identifying baseline predictors of pain intensity, disability, and psychological distress. Education level and physical fitness were consistent predictors of pain intensity, while gender, smoking status, and previous injury status were predictors of disability. Gender, smoking status, physical health scores, and beliefs of back pain were consistent predictors of psychological distress. These results provide additional data to confirm the multi-factorial nature of LBP and suggest future preventative interventions focus on multi-modal approaches that target modifiable risk factors specific to the population of interest.

Symptoms of Depression and Risk of New Episodes of Low Back Pain: A Systematic Review and Meta‐Analysis

“…The search strategy identified 7,765 unique studies that were all screened based on title and abstract, and resulted in 81 potentially eligible studies. Sixty-two studies were excluded based on full-text screening and, therefore, 19 articles (reporting data from 16 studies) were included in the review (6)(7)(8)(9)(10)(11)(18)(19)(20)(21)(22)(23)(24)(25)(26)(27)(28)(29)(30). Two published articles (20,22) reported findings of the same study and were both included in the review, as they provided results for different time points.…”

“…The samples were recruited from the general population in 13 articles (6)(7)(8)19,21,(23)(24)(25)(26)(27)(28)(29)(30) and from a workplace in 6 articles (9)(10)(11)18,20,22). The assessment of symptoms of depression varied across the studies, but overall they could be categorized into 3 groups: diagnostic interview, self-report screening questionnaires, and nonspecific screening questionnaires (questionnaires that assessed more general categories of psychological distress, including but not limited to, symptoms of depression).…”

“…Our pooled analyses are based on summary data from 11 studies (6,8,11,19,23,(25)(26)(27)(28)(29)(30). Two studies reported ORs from continuous data and were not included in the pooled analysis, as all the other 11 studies reported ORs from categorical data (9,10). The remaining studies could not be pooled as they did not provide enough data.…”

“…No statistically significant relationship was observed when we pooled the studies that employed nonspecific screening questionnaires (OR 1.17, 95% CI 0.48-2.87, I 2 5 76%) (Figure 3A). Among the studies that did not provide enough data to be pooled (i.e., provided only P value data), 2 studies reported symptoms of depression to be associated with new cases of LBP (21,22), and 3 studies did not find a significant association (9,10,18).…”

“…One of the recurring questions that is still unanswered is whether depression is a risk factor for LBP. Some studies have found depression to be associated with an increased risk of developing LBP (6)(7)(8), while other studies have failed to show a significant association (9)(10)(11). Previous reviews investigating the role of psychological variables in LBP have shown evidence of depression as a predictor of poor outcomes, such as chronicity, disability, and work absenteeism (12)(13)(14).…”