Effects of concurrent low back conditions on depression outcomes

Depression and low back problems are common issues in primary care.

To compare 6-month depression outcomes (specifically, clinical results and number of outpatient visits) in patients with or without comorbid low back conditions (LBCs). The authors hypothesized that the presence of an LBC within 3 months of the diagnosis of depression would negatively affect clinical outcomes of depression treatment after 6 months.

Retrospective record review.

Collaborative care management program in a large primary care practice.

Patients with a diagnosis of depression enrolled in collaborative care management (N=1326), including 172 with and 1154 without evidence of an LBC within 3 months of enrollment.

Clinical depression outcomes (remission and persistent depressive symptoms) and number of outpatient visits at 6 months.

Regression modeling for clinical remission and persistent depressive symptoms at 6 months demonstrated that LBCs were not an independent factor affecting clinical remission (P=.24) but were associated with persistent depressive symptoms (odds ratio, 1.559; 95% confidence interval, 1.065-2.282; P=.02); LBCs remained an independent predictor of outlier status for outpatient visits (≥8 clinical visits after 6 months of enrollment), with an odds ratio of 1.581 (95% confidence interval, 1.086-2.30; P=.02).

Increased odds of persistent depressive symptoms and increased number of outpatient visits were found in patients with depression and concomitant LBCs 6 months after enrollment into collaborative care management, compared with those in patients with depression and without LBCs. The data suggest that temporally related LBCs could lead to worse outcomes in primary care patients being treated for depression, encouraging closer observation and possible therapeutic changes in this cohort.