Increased Albuminuria Is Independently Associated with Peripheral Neuropathic Pain in Patients with Type 2 Diabetes

Background: Peripheral neuropathic pain is prevalent in patients with type 2 diabetes (T2D). This retrospective cross-sectional study aimed to examine the association between urinary albumin-to-creatinine ratio (UACR) and peripheral neuropathic pain in patients with T2D. Methods: Medical information was retrospectively collected from patients who underwent assessments of Identification Pain (ID Pain) and Douleur Neuropathique en 4 (DN4) questionnaires. Reduced estimated glomerular filtration rate (eGFR) was defined as an eGFR value < 60 mL/min/1.73 m2. Results: The prevalence of ID Pain scores ≥ 2 was significantly higher in the reduced eGFR group than the preserved eGFR group (p < 0.001). The prevalence of ID Pain scores ≥ 2 showed a positive trend from normal UACR to moderately and severely increased albuminuria in both the preserved eGFR (15.9%, 27.0%, and 33.8%; p < 0.001) and reduced eGFR (25.6%, 26.1%, and 37.1%; p = 0.035) groups. In multivariable regression analyses, the risk of ID Pain scores ≥ 2 significantly increased in the group with severely increased albuminuria (adjusted odds ratio: 2.016, 95% confidence interval: 1.471–2.763; p < 0.001) compared to the normal UACR group; however, reduced eGFR became not significantly associated with peripheral neuropathic pain (p = 0.466) after adjusting for confounding factors. Similar findings were replicated for peripheral neuropathic pain defined as DN4 scores ≥ 4. Conclusions: Peripheral neuropathic pain was significantly associated with increased albuminuria in both the reduced eGFR and preserved eGFR groups. However, a reduced eGFR was not independently associated with peripheral neuropathic pain.