Lower quality of life, lower limb pain with neuropathic characteristics, female sex, and ineffective metabolic control are predictors of depressive symptoms in patients with type 2 diabetes mellitus treated in primary care

The primary objective of this study was to identify if lower limb pain with neuropathic characteristics is predictive of depressive symptoms in patients with type 2 diabetes mellitus (T2DM) treated in primary care in Brazil. It was investigated if diabetic and non-diabetic related variables could influence depressive symptoms. A quantitative and cross-sectional study was carried out in two Basic Health Units with users of the Brazilian Public Healthcare System, who were evaluated for depressive symptoms (BDI), quality of life (QoL, SF6D), pain intensity, neuropathy (loss of plantar sensitivity—LOPPS), body composition (DEXA), biochemical tests, sociodemographic variables, and comorbidities. The patients were stratified into four groups: N⁺P⁺, N⁺P⁻, N⁻P⁺, and N⁻P⁻ (N = neuropathy and P = pain). One hundred twenty-one diabetics were selected by random sampling between August 2016 and June 2017. Neuropathy affected 53.8% of these individuals, and 59.5% reported intense pain. Overall depressive symptoms scores showed a positive correlation with pain intensity and a negative correlation with QoL. Depressive symptoms were reported by 66.9% of the sample, mostly female, with better levels of cholesterol, HDL and LDL; comorbidities; worse QoL; greater intensity of pain; impaired sleep; and painful neuropathy (N⁺P⁺). The predictive factors for depressive symptoms were lower QoL, pain with neuropathic characteristics, female sex, obesity, and ineffective glycemic control. These data may contribute to the understanding of the complexity of patients with T2DM who are treated in primary care and to public policies planning of care directed at the needs of this population.