OBJECTIVES: The goal of this cross-sectional evaluation was to assess pain impact and interference with mental functioning, symptom levels of anxiety and depression, and sleep impairment among patients with NeP. METHODS: Participants in an observational, prospective and multicentre study in Spain (DONEGA study) with NeP of different etiologies, completed the Short Form-McGill Pain Questionnaire (SF-MPQ), the Mini Mental State Examination (MMSE), the COVI Anxiety Scale, the RASKIN Depression Rating Scale, and the MOS Sleep Scale (MOS-S) at baseline. RESULTS: A total of 1519 patients above 18 years [mean ± SD; 56.0±13.7 years old (58.8% female)] with NeP were enrolled in the study. Peripheral NeP was presented in >95.0% subjects. Patients had NeP for 1.1±2.8 years, and 83.3% were on any type of analgesic treatment at baseline: oral analgesics (51.2%), topical analgesics (26.9%), NSAID's (11.1%), antiepileptics (7.3%), and psychoanaleptics (3.5%). Average Pain scores were 13.1±8.2 pts, 10.0±5.8 pts, and 3.1±3.3 pts, for total scale (range 0 – 45), sensory domain (range 0-33), and affective domain (range 0-12), respectively. Present pain intensity was 2.8±1.0 (range 0-5) and mean pain past week on a VAS scale was 71,2±18,9 mm. Pain slightly interfered with patient mental functioning (average MMSE score; 27.2±3.6 pts, 18.0% of patients with MMSE score ≤ 24 pts). Pain interfered with all sleep attributes, obtaining high scoring in composite measures; SLP6; 45.3±21.8, and SLP9; 46.8±21.1. The 24.4% and 15.6% of patients had moderate to severe symptoms levels of anxiety and depression (RASKIN and COVI scores ≥ 9 on 3 – 15 scale), with an average depression and anxiety scores of 6.3±3.3 pts and 5.4±2.8, respectively. CONCLUSIONS: NeP decreases patient mental functioning as assessed by MMSE, while increasing anxiety and depression symptoms and sleep problems. These findings substantially deteriorated with pain severity.