Assessment of neuropathic pain descriptors among patients attending at the Pain Unit of Maputo Central Hospital, Maputo, Mozambique a cross sectional study

Emília Pinto ^1,2,3, Amade Pinto Miquidade ⁴,Teresa Schwalbac⁵, João Schwalbach³

¹ Maputo Central Hospital  Pain Unit

² Eduardo Mondlane University

³ Higher Institute of Science and Technology of Mozambique

⁴ School of Medicine  Porto University

⁵ Mozambican Association for the Study of  Pain

Abstract

Background: About 1/3 of patients from low- and middle-income countries (LMICs), Mozambique have chronic pain. However, pain with neuropathic features is usually more severe and associated with poorer quality of life depending on its severity and  underlying causes. We aimed to describe the frequency of main descriptors among patients diagnosed with neuropathic pain at the Pain Unit of the Maputo Central Hospital.

Methods: This was a cross-sectional study carried out from September 2016 to May 2017 in 120 patients with chronic pain seen at the Pain Unit from Maputo Central Hospital where it was intended to screen for neuropathic pain using the Douleur Neuropathique 4 Questionnaire (DN4).  This assess evaluate 4 fundamental questions with yes/no answers: 2 related to the reported complaints where we evaluated pain characteristics such as burning, painful cold, electric shocks and the second to evaluate symptoms such as tingling, pins and needles,  numbness and itching, and the last 2 are physical examination with evaluations such as hypoesthesia to touch and hypoesthesia to pinprick . Overall, out of 120 patients with assessment ≥ 4 had a diagnosis of neuropathic pain corresponding to 69 (57.5%). In this secondary data analysis, we extracted only the 69 patients diagnosed with neuropathic pain and we evaluated the s main descriptions referenced and evaluated in the physical examination using the SPSS program for each of the 4 questions.

Results: From 69 patients, mean age 54 years, maximum age 89 years and minimum age 18 years, 66% were female.According to the characteristics of the pain the results were: burning 49 (71% ), electric shocks 42 (60.8%), painful cold 37 (53%); With regard to symptoms, we found for tingling, pins and needles 47 (68%) each,  numbness 36 (52%) and itching 25 (36.2%). Regarding to the physical examination for both tests, the results were to hypoesthesia to touch and hypoesthesia to pinprick 23 (33.3%) each; and for the last one the pain caused or increased by brushing 12 (17.3%) were positive.

Conclusion: we found that most patients that were screened for neuropathic pain using the DN4 questionnaire in Maputo Central Hospital Pain Unit, the patients' complaints contributed about 2/3 to their diagnosis compared to the physical examination findings, which reflects the importance of valuing all the complaints the patient presents for a correct diagnosis.

References:

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Relevance for Patient Care: this study once again reveals that the complaints referred by the patient must always be taken into account, associated with the physical examination in comparison with complementary tests for a diagnosis and better approach to neuropathic pain.

Ethical Permissions - The study was approved by Institucional Committee of  Bioethics for Medical School and Maputo Central Hospital – Mozambique

Keywords

Neuropathic pain patients, cronic pain, DN4 descriptors, low and meedle income countries.