A high prevalence of depression and anxiety symptoms was found among patients with painless or painful diabetic polyneuropathy (nDSPN or pDSPN) and patients with diabetes mellitus (DM) without polyneuropathy, according to findings published in the European Journal of Pain. The dominant risk factors found were the presence of neuropathic pain, as well as its severity and how it is processed cognitively (pain catastrophizing). Independent of pain, other important contributors were female sex, lower age, type 2 DM, and diabetic polyneuropathy severity.
Investigators conducted an observational, multicenter, cross-sectional, cohort study in the Czech Republic and Slovakia using the Beck Depression Inventory II (BDI II), the Hospital Anxiety and Depression Scale (HADS), and the State-Trait Anxiety Inventory (STAI-Y) to assess depression and anxiety symptoms in several groups with DM, as well as in a healthy control group.
The cohort included 347 patients with pDSPN (median age 63.4 years, 55.9% men), 311 patients with nDSPN (median age 63.7 years, 57.9% men), 50 patients with DM without polyneuropathy (median age 61.5 years, 44.0% men), and 71 control participants (age 63.0 years, 42.3% men). The role of emotional distress and psychological disturbances was explored in terms of clinical, biological, cognitive, and socioeconomic parameters.
In uncorrected groups, the percentages of scores reaching the 90th percentile abnormal cutoff for all questionnaires in the pDSPN group were 37.5% (STAI-Y2), 37.2% (HADS-A), 36.3% (HADS-D), 35.7% (BDI-II), and 31.7% (STAI-Y1). Among pDSPN patients, 46.7% had HADS-D and/or BDI-II scores that reflected depression symptoms; 60.5% had STAI-Y1, STAI-Y2, and HADS-A scores that reflected anxiety symptoms. Anxiety and depression prevalence was lower in nDSPN patients (44.4% and 24.4%, respectively; P <.001) but higher than controls (14.1% and 7.0%; P =.012 and P <.001).
Likewise, depression and anxiety prevalence was lower among DM patients compared with pDSPN patients (P =.001 and P <.001) but higher than among controls (P =.017 and P =.033).
In additional analysis of tests with corrected sex- and age-matched subgroups with equal and reduced number of participants, the pDSPN group showed a significantly higher median value of all depression and anxiety tests, which further increased with pain severity.
In the multiple regression analyses, functional relationships between emotional distress and independent variables were found. In depression models, 30.4% of HADS-D score variance could be accounted for by mean pain intensity (β=0.145; P =.032), pain catastrophizing scale (PCS) magnification score (β=0.282; P <.001), and diabetes type 2 (β=0.294; P <.001), while 27.9% of BDI-II variance could be accounted for by mean pain intensity (β=0.287; P <.001), age (β= −0.144; P =.046), female sex (β=0.191; P =.009), and PCS magnification score (β=0.291; P <.001).
In anxiety models, 20% of HADS-A score variance could be accounted for by mean pain intensity (β=0.243; P =.001), PCS magnification score (β=0.197; P =.005), and Type 2 DM (β=0.160; P =.021), while 12.2% of STAI-Y1 variance could be accounted for by mean pain intensity (β=0.168; P =.029), any clinical sensory disturbance (β=0.216; P =.006), and female sex (β=0.129; P =.057), and 21% of STAI-Y2 variance could be accounted for by mean pain intensity (β=0.249; P <.001), PCS magnification score (β=0.185; P =.008), female sex (β=0.182; P =.005), and BMI (β=0.165; P =.013).
The study was limited by an inadequate DM group sample size, and the fact that psychological questionnaires are prone to a number of biases. Nevertheless, investigators concluded that there appears to be high prevalence of symptoms of depression and anxiety symptoms not only in patients with painful diabetic polyneuropathy, but also in diabetic patients without pain.
Kec D, Rajdova A, Raputova J, et al. Risk factors for depression and anxiety in painful and painless diabetic polyneuropathy: a multicentre observational cross-sectional study [published online September 30, 2021]. Eur J Pain. doi:10.1002/ejp.1865