Amitriptyline for musculoskeletal complaints: a systematic review

Repurposing Antihypertensive and Statin Medications for Spinal Pain: A Mendelian Randomization Study

STUDY DESIGN

Mendelian randomization (MR) study.

OBJECTIVE

To examine whether antihypertensive medications (beta-blockers, calcium channel blockers, and angiotensin-converting enzyme inhibitors) and statins can be repurposed to prevent or treat spinal pain (back or neck pain).

SUMMARY OF BACKGROUND DATA

Observational studies and a recent MR study have found associations between elevated blood pressure and a greater risk of back pain. Observational studies have found associations between hyperlipidemia and statin use and greater risk of back pain. No prior MR studies have examined the effects of antihypertensives or statins on spinal pain.

MATERIALS AND METHODS

This was a two-sample MR study using publicly available summary statistics from large-scale genome-wide association studies (GWAS). Sample sizes in exposure GWASs were n=757,601 (systolic blood pressure) and n=173,082 (low-density lipoprotein cholesterol), and n=1,028,947 for the outcome GWAS of spinal pain defined as health care seeking for any spinal pain-related diagnosis. Genes and cis-acting variants were identified as proxies for the drug targets of interest. MR analyses used inverse-variance weighted meta-analysis. The threshold for statistical significance after correction for multiple testing was P <0.0125.

RESULTS

No statistically significant associations of these medications with spinal pain were found. However, findings were suggestive of a protective effect of beta-blockers on spinal pain risk (odds ratio [OR] 0.84, 95% confidence interval [CI] 0.72-0.98; P =0.03), and calcium channel blockers on greater spinal pain risk (OR 1.12, 95% CI 1.02-1.24; P =0.02).

CONCLUSIONS

A protective effect of beta-blockers on spinal pain was suggested in the current study, consistent with findings from observational studies of various other pain phenotypes. The detrimental effect of calcium channel blockers on spinal pain suggested in the current study must be interpreted in the context of conflicting directions of effect on nonspinal pain phenotypes in other observational studies.This Mendelian randomization study examined whether antihypertensive medications (beta-blockers, calcium channel blockers, and angiotensin-converting enzyme inhibitors) and statins can be repurposed to prevent or treat spinal.This was a two-sample MR study using publicly available summary statistics from large-scale genome-wide association studies ranging size from 173,082 to 1,028,947 adults.While no statistically significant associations were found, a protective effect of beta-blockers on spinal pain was suggested (odds ratio [OR] 0.84, 95% confidence interval [CI] 0.72 to 0.98; p= 0.03), as was a detrimental effect of calcium channel blockers on spinal pain (OR 1.12, 95% CI 1.02 to 1.24; p= 0.02).

Antidepressant and anticonvulsant prescription rates in patients with osteoarthritis: a population-based cohort study

Objectives

There are signs that antidepressants and anticonvulsants are being prescribed more often for OA patients, despite limited evidence. Our objectives were to examine prescription rates and time trends for antidepressants and anticonvulsants in OA patients, to assess the percentage of long-term prescriptions, and to determine patient characteristics associated with antidepressant or anticonvulsant prescription.

Methods

A population-based cohort study was conducted using the Integrated Primary Care Information database. First, episodic and prevalent prescription rates for antidepressants (amitriptyline, nortriptyline and duloxetine) and anticonvulsants (gabapentinoids) in OA patients were calculated for the period 2008–17. Logistic regression was used to assess which patient characteristics were associated with prescriptions.

Results

In total, 164 292 OA patients were included. The prescription rates of amitriptyline, gabapentin and pregabalin increased over time. The increase in prescription rates for pregabalin was most pronounced. Episodic prescription rate increased from 7.1 to 13.9 per 1000 person-years between 2008 and 2017. Amitriptyline was prescribed most (15.1 episodic prescriptions per 1000 person-years in 2017). Prescription rates of nortriptyline and duloxetine remained stable at 3.0 and 2.0 episodic prescriptions per 1000 person-years, respectively. For ≤3% of patients with incident OA, medication was prescribed long-term (≥3 months). In general, all medication was prescribed more frequently for older patients (except duloxetine), women, patients with OA in ≥2 joints, patients with spinal OA and patients with musculoskeletal disorders.

Conclusion

Prescription rates of amitriptyline, gabapentin and pregabalin increased over time. Since there is little evidence to support prescription in OA, caution is necessary when prescribing.

Comparative safety review of current treatment options for chronic low back pain and unmet needs: a narrative review

Introduction: The healthcare expenditures in the United States are substantial for the management of refractory, chronic low back pain (CLBP). The objective of this review is to summarize and evaluate the safety profiles of different pharmacological treatment options used in the management of CLBP.Areas covered: The authors conducted a search of randomized controlled trials (RCTs) assessing the safety profiles of different pharmacological agents used in the management of CLBP. This narrative review covered corticosteroids, opioids, antidepressants, gabapentinoids, nonsteroidal anti-inflammatory drugs, muscle relaxants, anti-nerve growth factor antibodies and topical agents, as monotherapy or in combination.Expert opinion: The risk-benefit ratio of a particular treatment is a subject driving the ongoing development of pharmaceuticals. The most commonly reported AEs across all drug classes are of gastrointestinal nature, followed by neurological and skin-related. These AEs include nausea, dizziness, constipation, arthralgia, headache, dry mouth, pruritus, etc. The majority of the AEs reported are not life-threatening, although they may lower patients' quality of life, thus, affecting their compliance. One of the biggest limitations of our review stems from the paucity of safety assessments in published RCTs. Advances in our understanding of the neurobiology of pain will promote development of new therapeutic strategies.

Relevance of Diagnosed Depression and Antidepressants to PROMIS Depression Scores Among Hand Surgical Patients

PURPOSE

We aimed to test the utility of screening for depressive symptoms in the hand surgical office focusing on chances of heightened depressive symptoms in patients with no history of diagnosed depression and by quantifying ongoing depressive symptoms among patients diagnosed with depression accounting for antidepressant use. The clinical importance of this study was predicated on the documented negative association between depressive symptoms and hand surgical outcomes.

METHODS

This cross-sectional study analyzed 351 patients presenting to a tertiary hand center between April 21, 2016, and November 22, 2017. Adult patients completed self-administered Patient-Reported Outcomes Measurement Information System (PROMIS) Depression computer adaptive tests at registration. Health records were examined for a past medical history of diagnosed depression and whether patients reported current use of prescription antidepressants. Mean PROMIS Depression scores were compared by analysis of variance (groups: no diagnosed depression, depression without medication, depression with medication). Four points represented a clinically relevant difference in PROMIS Depression scores between groups and Depression scores greater than 59.9 were categorized as having heightened depressive symptoms.

RESULTS

Sixty-two patients (18%) had been diagnosed with depression. Thirty-four of these patients (55%) reported taking antidepressant medications. The PROMIS Depression scores indicated greater current depressive symptoms among patients with a history of diagnosed depression when not taking antidepressants (11 points worse than unaffected) and also among patients taking antidepressants (7 points worse than unaffected). Heightened depressive symptoms were detected in all groups but were more prevalent among those diagnosed with depression (36% with no medication, 29% with antidepressant medication) compared with unaffected patients (7%).

CONCLUSIONS

Depression screening for heightened depressive symptoms identifies 1 in 14 patients without diagnosed depression and 1 in 3 patients diagnosed with depression as having currently heightened depressive symptoms. Hand surgeons can use PROMIS Depression screening in all patients and using this to guide referrals for depression treatment to ameliorate one confounder of hand surgical outcomes.

TYPE OF STUDY/LEVEL OF EVIDENCE

Symptom prevalence study II.

Examination and characterisation of the effect of amitriptyline therapy for chronic neuropathic pain on neuropeptide and proteomic constituents of human cerebrospinal fluid

INTRODUCTION

Amitriptyline is prescribed to reduce the intensity of chronic neuropathic pain. There is a paucity of validated in vivo evidence in humans regarding amitriptyline's mechanism of action. We examined the effect of amitriptyline therapy on cerebrospinal fluid (CSF) neuropeptides and proteome in patients with chronic neuropathic pain to identify potential mechanisms of action of amitriptyline.

METHODS

Patients with lumbar radicular neuropathic pain were selected for inclusion with clinical and radiological signs and a >50% reduction in pain in response to a selective nerve root block. Baseline (pre-treatment) and 8-week (post-treatment) pain scores with demographics were recorded. CSF samples were taken at baseline (pre-treatment) and 8 weeks after amitriptyline treatment (post-treatment). Proteome analysis was performed using mass spectrometry and secreted cytokines, chemokines and neurotrophins were measured by enzyme-linked immunosorbent assay (ELISA).

RESULTS

A total of 9/16 patients experienced a >30% reduction in pain after treatment with amitriptyline and GO analysis demonstrated that the greatest modulatory effect was on immune system processes. KEGG analysis also identified a reduction in PI3K-Akt and MAPK signalling pathways in responders but not in non-responders. There was also a significant decrease in the chemokine eotaxin-1 (p ​= ​0.02) and a significant increase in the neurotrophin VEGF-A (p ​= ​0.04) in responders.

CONCLUSION

The CSF secretome and proteome was modulated in responders to amitriptyline verifying many pre-clinical and in vitro models. The predominant features were immunomodulation with a reduction in pro-inflammatory pathways of neuronal-glia communications and evidence of a neurotrophic effect.

Therapeutic Drug Monitoring of Antidepressants for the Treatment of Chronic Musculoskeletal Pain With and Without Depression

BACKGROUND

Antidepressants are recommended for the treatment of chronic musculoskeletal pain; however, target serum concentrations based on therapeutic drug monitoring (TDM) have not been established. Therefore, the authors analyzed routine care TDM data of antidepressants in patients with chronic pain with and without depression in terms of treatment outcomes in an interdisciplinary multimodal pain treatment (IMPT) program.

METHODS

Patients with chronic musculoskeletal pain and TDM for amitriptyline (n = 45) or duloxetine (n = 30) were retrospectively included. The German pain questionnaire for pain intensity and the Depression Anxiety Stress scale were applied at T0 and at the end of the IMPT program (T1). A relief of pain intensity score ≥2 was considered as a positive outcome. Comorbid depression was diagnosed based on ICD-10 criteria. Serum concentrations of antidepressants were measured for routine clinical care TDM.

RESULTS

After IMPT, stress improved in all subgroups, and depressive symptoms improved only in the duloxetine group. Overall, 40% and 27% of patients in the amitriptyline and duloxetine subgroup, respectively, were responders in terms of maximum pain score relief. Responders with comorbid depression were treated with a dose that led to a 1.7-fold higher serum concentration of the active moiety of amitriptyline (amitriptyline + nortriptyline) compared with nonresponders. Similarly, a 2.3-fold higher serum concentration was observed in depressed responders than in nondepressed responders (at minimum 131.5 ng/mL).

CONCLUSIONS

Dosing of antidepressants for chronic pain relief should specifically take comorbid depression into account. TDM may provide better outcomes of pain relief in an IMPT setting in patients with comorbid depression.

Incidence of Depression and First-Line Antidepressant Therapy in People with Obesity and Depression in Primary Care

OBJECTIVE

The aim of this study was to describe the age- and gender-specific incidence of depression, the dose-response relationship between BMI and risk of depression (Cox proportional hazards), and antidepressant drug prescribing in adults with overweight or obesity.

METHODS

A retrospective electronic health record study using the Clinical Practice Research Datalink was conducted to identify adults with overweight and obesity (≥ 18 years) with incident depression (no prior depression diagnosis in their records), followed up from 2000 to 2019.

RESULTS

Among 519,513 adults, incidence of depression was 9.2 per 1,000 person-years and was higher in women and in 40- to 59-year-old men who had severe obesity. Compared with having overweight, the hazard of depression increased with each BMI category as follows: 1.13 (30-34 kg/m² ; 95% CI: 1.10-1.16), 1.34 (35-39 kg/m² ; 1.29-1.40), 1.51 (40-44 kg/m² ; 1.41-1.61), and 1.67 (45-49 kg/m² ; 1.48-1.87), attenuating at BMI 50+ kg/m² (1.54; 2.91-1.84). Antidepressants were prescribed as first-line therapy in two-thirds (66.3%) of cases. Prescriptions for fluoxetine reduced over time (20.4% [2000]; 8.8% [2018]), and prescriptions for sertraline increased (4.3% [2000]; 38.9% [2018]).

CONCLUSIONS

We recommend guidance on antidepressant drug prescribing and specific services for people with obesity and depression that address both symptoms and behaviors.

Amitriptyline prescribing in public sector healthcare facilities in the Western Cape, South Africa

BACKGROUND

Inappropriate medication use is a major patient safety concern, especially for the elderly population. Amitriptyline is widely used in primary care in South Africa and a cross-sectional study found that amitriptyline was prescribed potentially inappropriately in 6.5% of elderly patients. An analysis of prescriptions from the Chronic Dispensing Unit in the Western Cape revealed that amitriptyline was one of the most common medicines prescribed without a suitable diagnosis listed on the prescription.

OBJECTIVE

The main objective of the medicine use evaluation (MUE) was to determine whether amitriptyline was prescribed in accordance with recommendations from standard treatment guidelines (STG) and essential medicines lists (EML) endorsed by the National Department of Health, South Africa.

METHODS

A retrospective, cross-sectional, multicentre review of patients' clinical notes was conducted. The study population was selected by systematic random sampling from adult outpatients who were prescribed amitriptyline for longer than three months. Criteria for evaluation included amitriptyline indication and total daily dose prescribed.

RESULTS

Of the sample of 2237 patient medical records reviewed, 1732 (77.4%) included amitriptyline prescriptions that were according to the approved STG indications. For the approved STG indications, amitriptyline was prescribed mainly for osteoarthritis (25.8%), neuropathies (18.5%) and chronic non-cancer pain (17.9%). Major depressive disorders constituted only 8.6% of the patient records reviewed; however, doses were atypically low. The main inappropriate indication for amitriptyline was sleep disorders (16%).

CONCLUSION

This MUE has highlighted the need to improve the use of amitriptyline in specific patient populations, e.g. the elderly and patients with sleeping disorders.

A methodological quality assessment of systematic reviews and meta-analyses of antidepressants effect on low back pain using updated AMSTAR

BACKGROUND

Antidepressants are prescribed widely to manage low back pain. There are a number of systematic reviews and meta-analyses which have investigated the efficacy of the treatments, while the methodological quality of them has not been assessed yet. This study aims to evaluate the methodological quality of the systematic reviews and meta-analyses investigating the effect of antidepressants on low back pain.

METHODS

A systematic search was conducted in PubMed, EMBASE, Medline, and Cochrane Library databases up to November 2018. The 16-item Assessment of Multiple Systematic Reviews (AMSTAR2) scale was used to assess the methodological quality of the studies. Systematic reviews and meta-analyses of the Antidepressants treatment effects on low back pain published in English language were included. There was no limitation on the type of Antidepressants drugs, clinical setting, and study population, while non-systematical reviews and qualitative and narrative reviews were excluded.

RESULTS

A total of 25 systematic reviews and meta-analyses were evaluated; the studies were reported between 1992 and 2017. Obtained results from AMSTAR2 showed that 11 (44%), 9 (36%) and 5 (20%) of the included studies had high, moderate and low qualities, respectively. 13(52%) of studies assessed risk of bias and 2(20%) of meta analyses considered publication bias. Also, 16 (64%) of the included reviews provided a satisfactory explanation for any heterogeneity observed in the results.

CONCLUSIONS

Although the trend of publishing high quality papers in ADs effect on LBP increased recently, performing more high-quality SRs and MAs in this field with precise subgroups of the type of pains, the class of drugs and their dosages may give clear and more reliable evidence to help clinicians and policymakers.

Monoamines as Drug Targets in Chronic Pain: Focusing on Neuropathic Pain

Monoamines are involved in regulating the endogenous pain system and indeed, peripheral and central monoaminergic dysfunction has been demonstrated in certain types of pain, particularly in neuropathic pain. Accordingly, drugs that modulate the monaminergic system and that were originally designed to treat depression are now considered to be first line treatments for certain types of neuropathic pain (e.g., serotonin and noradrenaline (and also dopamine) reuptake inhibitors). The analgesia induced by these drugs seems to be mediated by inhibiting the reuptake of these monoamines, thereby reinforcing the descending inhibitory pain pathways. Hence, it is of particular interest to study the monoaminergic mechanisms involved in the development and maintenance of chronic pain. Other analgesic drugs may also be used in combination with monoamines to facilitate descending pain inhibition (e.g., gabapentinoids and opioids) and such combinations are often also used to alleviate certain types of chronic pain. By contrast, while NSAIDs are thought to influence the monoaminergic system, they just produce consistent analgesia in inflammatory pain. Thus, in this review we will provide preclinical and clinical evidence of the role of monoamines in the modulation of chronic pain, reviewing how this system is implicated in the analgesic mechanism of action of antidepressants, gabapentinoids, atypical opioids, NSAIDs and histaminergic drugs.