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Special Issue on Pain in the Developing World (Guest Editor, Daniel Ciampi de Andrade)

State of clinical pain research in Nepal: a systematic scoping review

Sharma, Sauraba,b,*; Jensen, Mark P.c; Pathak, Anupab; Sharma, Sweekritid,e; Pokharel, Mukeshf; Abbott, J. Haxbyb

Author Information
doi: 10.1097/PR9.0000000000000788

Abstract

1. Background

Given its high prevalence, costs, and impact on physical, mental, and social function, and all aspects of quality of life,48 pain remains a significant health problem worldwide.12 One-year prevalence of chronic pain is more in developing countries (41%) compared with developed countries (37%).47 The economic burden of chronic pain is extremely high, with annual estimates of the cost of treatment in the United States to be from US$ 560 billion and US$ 635 billion12 and about £1 billion in the United Kingdom.47

Knowledge from pain research comes predominantly from developed countries; pain research in developing countries—including Nepal—is relatively sparse. Currently, musculoskeletal pain conditions are the number one cause of disability in Nepal with a 32% increase in the last 3 decades.9,11 Despite this, pain is not currently viewed as a priority research area in Nepal. For example, the Nepal Health Research Council's (NHRC) research priority agenda does not include pain research as one of its priorities.21 However, recently, there have been promising signs that research related to pain in Nepal is growing.17,25,30,32,36,38,45

Given the scarce resources for performing research in Nepal in general, it is important that researchers should (1) avoid duplicating research efforts and (2) address the research questions that are most likely to be impactful. Thus, the purpose of this review is to clarify the current state of pain research in Nepal, identify the extent and nature of research published, identify significant knowledge gaps, and provide recommendations for future studies. To achieve these aims, here, we included studies irrespective of study design that focused on a range of topics, including research that evaluated interventional procedures (eg, medical, surgical, and rehabilitation), epidemiological research, and outcome measurement studies, among others. As a part of this review, we also hoped to estimate the prevalence of pain conditions, to identify the outcome measures used to assess pain and related domains, and the treatment approaches used to treat pain conditions in Nepal.

2. Methods

A scoping review was conducted using recent guidelines.26 The study aims and methods were defined a priori. An extension of Preferred Reporting Items for Systematic reviews and Meta-Analysis (PRISMA) guidelines for scoping reviews was followed for reporting the review.46

2.1. Study eligibility criteria

We included studies that (1) were conducted in Nepal; (2) included participants who had a diagnosis of a clinical pain condition (eg, low back pain, headache, chronic pain, musculoskeletal pain, neuropathic pain, postsurgical pain, pediatric pain, cancer pain, etc) or included pain as the primary outcome (eg, fracture management); and (3) used either qualitative or quantitative research designs. We did not exclude studies based on language of publication, year of publication, study design, or age of study participants. However, we did exclude studies that (1) included healthy volunteers and animals instead of human participants; (2) were editorials or review articles; (3) included participants who did not have a clear pain condition or diagnosis, or had pain as only 1 symptom of another primary condition being studied (eg, infectious diseases such as typhoid); or (4) were conducted outside of Nepal.

2.2. Search strategy

We searched MEDLINE, Embase, Scopus, Cochrane library, Google Scholar, and Nepal Journals Online (NepJOL, https://www.nepjol.info/) from inception to November 2018. We also searched the reference lists of included studies. We collated articles in the Endnote software and removed duplicates. The lead author (S.S.) developed the search strategy and amended it after receiving feedback from all authors. We used a combination of terms “pain” or “analgesia” and “Nepal” or their alternative terms and adapted search strategies for each database. Details of search terms and strategies used can be found as supplementary file 1a (available at http://links.lww.com/PR9/A54).

2.3. Data screening

A pair of authors (S.S. and Sw.S., and A.P. and M.P.) independently screened the title and abstract of all the articles. Disagreements about inclusion were resolved through discussions. A third independent reviewer (S.S. or A.P.) who was not a member of the original pair made a final decision in case consensus was not reached. We then performed the screening of the full-text articles that required further reading. Next, we performed data charting (see below).

2.4. Data charting process

Data charting was performed using an Excel spreadsheet created by S.S. The form was pretested on 10 studies by first 5 study authors and finalized. One of 4 authors (A.P., M.P., S.S., and Sw.S.) then extracted data from the included studies, and a second author confirmed that the data were extracted correctly. If included studies were authored or coauthored by one of the authors of this review, a review author who was not the author of the study extracted the data. Any discrepancies were discussed with S.S., and the final decision was made through consensus. Based on the results from all the studies included, the lead author (S.S.) classified the studies into key themes to organize the presentation and discussion.

2.5. Data items

We extracted data related to (1) the year of publication, (2) place of data collection/research, (3) source of publication (local or international journal, PubMed indexed or not indexed journal), (4) study design (qualitative study, clinical trial, study protocol, observational design, case series, or case studies), (5) study setting (clinical, community, or mixed), (6) population studied (headache pain, musculoskeletal pain, postoperative pain, and low back pain), (7) participant characteristics (age and sex), (8) measures used, (9) treatment delivered, and (10) key findings.

2.6. Synthesis of results

We computed the frequency for publication types, setting (community or hospital), study design, type of pain condition, age categories, and scope of the study. We then classified the results based on the broader themes of pain research, for example, interventional studies (medical or surgical management and rehabilitation), epidemiological studies, outcome measurement studies, and diagnostic studies.

3. Results

A total of 1414 articles were identified, of which 116 studies were included in the review (Fig. 1). A complete list of included studies is presented in the supplementary file 1b (available at http://links.lww.com/PR9/A54).

Figure 1.
Figure 1.:
Flow diagram.

3.1. Characteristics of sources of evidence

Eighty-seven studies (75%) were published in Nepalese journals. Eighty-five studies (73%) were conducted in clinical settings and 8 (7%) in community settings. The most common study design was cross-sectional design (40%), followed by randomized controlled trials (35%). The most commonly studied pain condition was postsurgical pain (33%), followed by musculoskeletal pain (16%), headache (14%), and low back pain (13%). The majority of studies were conducted in adults (76%), followed by studies that included both adolescents and adults together (9%). Only 3% of the studies were conducted with children only. Detailed characteristics of included studies are presented in Table 1.

Table 1
Table 1:
Characteristics of sources of evidence.

3.2. Themes of identified studies

A total of 40% studies focused on medical management, followed by studies on prevalence/incidence of pain conditions (21%), diagnostic studies (15%), and surgical management and outcome measurement (8% each; see Fig. 2 and the Tables in supplementary file 2, available at http://links.lww.com/PR9/A54).

Figure 2.
Figure 2.:
Study scope or purpose.

3.2.1. Interventional studies

A total 29 of 46 studies (63%) studied postoperative analgesia. Four studies (9%) tested the effectiveness of steroid injections and 3 the effectiveness of epidural steroids for back pain. The most commonly studied postoperative pain management drug was bupivacaine (n = 17), followed by morphine (n = 9) and tramadol (n = 6). Nine studies (8%) evaluated the role of surgical procedures in pain. Only 3 studies studied rehabilitation interventions, 2 of which studied effect of posture on post-lumbar puncture headache, and 1 was a protocol of a feasibility trial.14,15,29

3.2.2. Prevalence and incidence of pain conditions

Estimates of prevalence or incidence of musculoskeletal conditions were most commonly studied (n = 9 studies), followed by headache disorders (n = 8), chronic pain (n = 2), and neuropathic pain (n = 2).

Prevalence of any pain condition in a community sample was 50%, 94% of which were chronic pain.3 Prevalence of low back pain ranged from 52% to 91%, and musculoskeletal pain ranged from 35% to 70%. In a large population level survey of 2100 individuals, 85% of the participants reported headache in the last year.20 Details are summarized in Table 2.

Table 2
Table 2:
Prevalence of pain conditions.

3.2.3. Outcome measurement studies

Nine studies focused on outcome measurement1,25,31–35,37,39 with 7 examining the psychometric properties of patient-reported measures in pain population.

3.2.4. Diagnostic imaging and investigation studies

Of 17 diagnostic studies identified, 3 used computed tomography scan in diagnosis of headache disorders10,22,43 and 3 used a magnetic resonance imaging for diagnosis of low back pain.13,24,44

3.2.5. Cost of pain treatment

One community survey on a sample of 882 participants in Eastern Nepal reported the cost of chronic pain treatment, with the participants reporting that they spent an average of 8.4% of their total income for chronic pain treatment.3

4. Discussion

This systematic scoping review of research related to pain in Nepal identified 116 articles. Most studies evaluated the efficacy of biomedical interventions or studied pain prevalence. These findings indicate a predominance of the biomedical model of pain in Nepal. The review also identified some areas of research redundancy and critical knowledge gaps, which have both research and clinical implications for Nepal, and also perhaps for other similar developing countries.

4.1. Areas of research redundancy

Most published studies asked similar (and sometimes even the same) research question(s) in identifying optimal medical management of postoperative pain, effect of posture on spinal headache, or use of imaging for diagnosis of a nonspecific pain conditions. This suggests a potential problem of a waste of limited research resources. Also, the focus on imaging research represents a potential ethical problem, given that diagnostic imaging is rarely recommended for chronic pain management.

4.2. Knowledge gaps

The findings highlight several gaps in the topic areas of pain research in Nepal. First, no studies were identified that sought to estimate the incidence or prevalence of a number of important pain conditions, or pain in specific populations, including pediatric pain, cancer pain, and pain in ageing populations. Also, the studies that estimated the prevalence of pain conditions were usually limited to very specific regions of the country and had small samples. Large population-level studies to estimate prevalence and incidence of various pain conditions would provide better estimates of disease burden. Third, research studies to cross-culturally adapt patient-reported outcome measures were limited to adult populations and patients with chronic pain or musculoskeletal pain. Cross-cultural adaptation of patient-reported outcome measures in other pain populations is needed to advance research in these areas. Finally, there were very few studies that focused on biopsychosocial assessment and pain management.

4.3. Recommendations for research

4.3.1. Limiting redundant research

Several approaches could be adapted to limit redundant research. First, researchers should perform comprehensive reviews of the literature before conducting any clinical trial. If meta-analyses of intervention studies have not been reported in the literature, this would be a more valuable contribution than a redundant additional trial. Second, associations and the national research authority (NHRC, Nepal Medical Council, and Nepalese Association for the Study of Pain in the context of Nepal) should consider encouraging researchers to prospectively register clinical trials. Along these lines, national journals should mandate clinical trial registration before data collection for an article to be considered for publication, consistent with the recommendations from International Committee of Medical Journal Editors.5

4.3.2. Mobilizing research funding for pain research

Addressing the burgeoning pain problem in Nepal requires more thoughtful use of limited research funds. Identifying pain as a research priority is the first step. Funding should be directed towards (1) developing additional culturally appropriate outcome measures, (2) implementing clinical practice guidelines, (3) evaluating the challenges for implementation of guidelines, and (4) conducting effectiveness trials of population-level interventions, including the analysis of cost-effectiveness.

4.3.3. Administering scales and outcome measures

Researchers should consider using valid, reliable, and responsive instruments with reference to core-outcome sets for clinical trials.4,6 When a desirable instrument is unavailable in a local language, a first step would be to cross-culturally adapt and validate the needed instrument(s) using recommended guidelines.2,7

4.4. Recommendations for practice

Overall, clinical assessment and treatment of pain should align more with contemporary clinical practice guidelines. The respective regulatory authorities and pain society should reinforce the use of treatment guidelines among their members.

4.4.1. Preventing overdiagnosis and overtreatment of pain conditions

Clinicians should stop routinely using expensive and sometimes invasive diagnostic procedures, including imaging, for nonspecific pain conditions.8,28,42 These diagnostic procedures can have significant costs and have limited benefits.40 The “Choosing Wisely” Campaign (www.choosingwisely.org) could help clinicians and consumers in appropriate use of diagnostic tests and interventions in Nepal.

Invasive interventions, including surgeries and injections which continue to be provided for the management of pain conditions in Nepal, have significant risks and have been shown to have limited benefits.16,18,19,23,27,41 Thus, some of these treatments should be avoided until further better evidence supports their safety and efficacy.

4.5. Study strengths and limitations

We adapted recommended guidelines for conducting and reporting a scoping review26,46 and performed comprehensive literature searches. However, we did not search the grey literature (other than Google Scholar). A systematic review of the research literature that included a critical appraisal of methodological quality of pain research conducted in Nepal would provide an overview of quality of research conducted in the country.

5. Conclusions

Most articles identified focused on the biomedical diagnosis and treatment of pain, suggesting a biomedical focus of pain research and clinical practice in Nepal. Pain diagnosis and management should be in line with clinical practice guidelines, include more comprehensive contemporary biopsychosocial approaches, and a pain research priority agenda should be supported at the national level.

Disclosures

Eleven of 116 included studies (9%) are authored by one or more author(s) of the current scoping review. Otherwise, the authors have no other conflicts of interest to declare.

Appendix A. Supplemental digital content

Supplemental digital content associated with this article can be found online at http://links.lww.com/PR9/A54.

Acknowledgements

The study did not receive any research funding. S. Sharma and A. Pathak are supported by University of Otago Doctoral Research Scholarship.

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Keywords:

Pain; Pain management; Chronic pain; Headache; Back pain; Musculoskeletal pain; Postoperative pain; Developing countries; Nepal

Supplemental Digital Content

Copyright © 2019 The Author(s). Published by Wolters Kluwer Health, Inc. on behalf of The International Association for the Study of Pain.