Peripheral neuropathy and depressive symptoms: examining the association in a primary health care setting among persons with and without diabetes mellitus

The purpose of this study was to measure the association between peripheral neuropathy symptoms and depressive symptoms among a sample of patients with and without diabetes mellitus (DM).

Patients were administered the 15-item Michigan Neuropathy Screening Instrument (MNSI) and the patient health questionnaire depression scale (PHQ-8). Patients with an MNSI score ≥ 4 were categorized as having PN and patients with a PHQ-8 score ≥ 10 were considered to have current depression. Log-binomial regression was used to analyze the relationship between PN and depressive symptoms.

406 patients were included in the final analysis. There were no statistically significant differences by diabetes status in PN symptoms (Diabetes = 61.8%; No diabetes = 55.4%; p = .20) or in depression status (Diabetes = 37.6%; No diabetes = 36.6%; p =  .83). After adjustment for covariates, PN was associated with depression (aRR = 4.46; 95% CI 2.91,6.85) independent of diabetes status.

PN symptoms may be common among aging persons even in the absence of DM. Past literature and our study demonstrate that PN and depression are closely associated. More work is needed to understand the etiology and potential utility of intervention for depression symptoms among patients with neuropathy.