Serotonin norepinephrine reuptake inhibitors in managing neuropathic pain following spinal and non-spinal surgery: A systematic review and meta-analysis of randomized controlled trials

BACKGROUND

While serotonin norepinephrine reuptake inhibitors (SNRIs) offer promise in managing Post-surgical neuropathic pain (PSNP), uncertainties remain. This study aims to evaluate the effectiveness and adverse events of SNRIs in managing PSNP.

METHODS

Systematic searches of PubMed, Embase, and Cochrane databases up to January 1st 2023 identified randomized controlled trials (RCTs) comparing SNRIs to placebo for PSNP. The primary outcome measures were pain at rest and adverse events post-surgery. Subgroup analyses were conducted based on surgical type and specific SNRIs.

RESULTS

A total of 19 RCTs, encompassing 1440 participants (719 in the SNRI group vs 721 in the placebo group), met the inclusion criteria and were included. The pooled results demonstrated that pain scores were significantly lower in patients treated with SNRIs at 2 hours (MD:-0.26; 95%CI: -0.47 to -0.04; p=0.02), 6 hours (MD:-0.68; 95%CI: -1.01 to -0.34; p<0.0001), 24 hours (MD:-0.54; 95%CI: -0.99 to -0.09; p=0.02), and 48 hours (MD:-0.66; 95%CI: -1.23 to -0.10; p=0.02) post-surgery. In terms of adverse events, dizziness (OR:2.53; 95%CI: 1.34-4.78; p=0.004) and dry mouth (OR:2.21; 95%CI: 1.25-3.92; p=0.007) were significantly higher in the SNRIs group. Subgroup analysis showed that SNRI was found to significantly lower the 24-hour pain score after spinal surgery (MD:-0.45; 95%CI: -0.84 to -0.05; p=0.03). Duloxetine (MD:-0.63; 95%CI: -1.15 to -0.11; p=0.02) had a significant effect in lowering the 24-hour pain score at rest compared to placebo, whereas venlafaxine did not.

CONCLUSIONS

SNRIs yielded considerable pain score reductions across multiple post-surgical intervals, although accompanied by an increased incidence of dizziness and dry mouth.

Potential Effect of Vortioxetine on Restless Leg Syndrome

Restless legs syndrome (RLS) is a chronic progressive movement disorder characterized by abnormal sensations, especially at rest and at night, as the need and urge to move the lower extremity. It has been reported that RLS severity and frequency increase in patients with anxiety and depression. It has been reported that serotonin-noradrenaline reuptake inhibitors such as venlafaxine and selective serotonin reuptake inhibitors such as citalopram, fluoxetine, paroxetine, and sertraline can cause RLS symptoms. No adverse effects of vortioxetine on RLS have been reported in the literature. In this case series, we report the effect of vortioxetine in patients with RLS with symptoms of depression and anxiety. In this case series, the effect of adding vortioxetine to treatment on RLS symptoms is reported in 7 patients (5 female). After the use of vortioxetine, 5 of 7 patients' symptoms regressed without the need to start a separate drug for primary movement disorder. In conclusion, we believe that studies should be conducted to investigate the efficacy of vortioxetine in the treatment of RLS. Therefore, randomized controlled studies are needed to determine the effect and safety of vortioxetine on RLS symptoms.

Effectiveness and adverse effects of the use of mirtazapine as compared to duloxetine for fibromyalgia: real-life data from a retrospective cohort

On the background of a restricted armamentarium of drugs available for the management of fibromyalgia (FM), we aimed to compare the real-world effectiveness of two serotonin-norepinephrine reuptake inhibitors (SNRIs), mirtazapine (MTZ) and duloxetine (DLX) in FM. A medical records review was done to identify patients diagnosed with FM and prescribed a stable dose of either MTZ or DLX for more than 6 months. Their present status was determined by a telephonic interview which included a subjective assessment of improvement (Likert scale), FIQR (Revised Fibromyalgia Impact Questionnaire), adverse drug effects and compliance. One-fifty-eight patients were screened to include 81 patients [mean age 46.7 (± 13.0) years, 64 (79%) females]. Sixty (79%) had primary fibromyalgia and 66 (81.5%) were on DLX (20-40 mg) while 15(18.5%) were on MTZ (7.5 mg). In addition to the drugs, lifestyle modification was followed by 57 (70.3%). A moderate-to-good improvement was seen in 66 (81.5%), while 15 (18.5%) reported poor to no improvement overall. In the DLX group, a majority (59, 89.4%) showed moderate-to-good improvement compared to 7(46.7%) on MTZ [p = 0.001, 9.6(2.6-34)]. However, FIQR was similar for those on DLX (3.6 ± 0.9) and MTZ (3.8 ± 0.7). Adverse effects were reported for 51 (77%) of patients on DLX and all (100%) on MTZ with a poorer compliance with MTZ 5 (33.3%) compared to DLX 47 (71.2%) [p = 0.008, OR 0.1(0.03-0.4)]. On multivariate analysis, DLX use [OR 16.7 (95% CI 2.7-100); p = 0.008] and lifestyle modification [p = 0.002; OR 11.2(1.5-83.3)] were associated with better subjective outcomes. Low-dose MTZ appears to be inferior to DLX in the management of FM in this real-world cohort.

Selective Serotonin Re-Uptake Inhibitors for Premature Ejaculation in Adult Men: A Cochrane Systematic Review

PURPOSE

Selective serotonin re-uptake inhibitors (SSRIs) are frequently used to treat premature ejaculation (PE) in men. We performed a Cochrane review to assess the efficacy of SSRI treatment for PE.

MATERIALS AND METHODS

We extensively searched a range of databases up to May 2020 and only included randomized controlled trials.

RESULTS

A total of 31 studies with 8,254 men were included in this analysis. We found that SSRI treatment probably improves self-perceived PE symptoms (defined as a rating of 'better' or 'much better'; risk ratio [RR], 1.92; 95% confidence interval [CI], 1.66-2.23; moderate-certainty evidence) and satisfaction with intercourse (defined as a rating of 'good' or 'very good'; RR, 1.63; 95% CI, 1.42-1.87; moderate-certainty evidence) compared to placebo. Furthermore, SSRI treatment likely improve participants' self-perceived control over ejaculation (defined as rating of 'good' or 'very good'; RR, 2.29; 95% CI, 1.72-3.05; moderate-certainty evidence) and probably lessens distress (defined as rating of 'a little bit' or 'not at all') about PE (RR, 1.54; 95% CI, 1.26-1.88; moderate-certainty evidence). SSRI treatment may increase IELT compared to placebo (mean difference, 3.09 minutes higher; 95% CI, 1.94 higher to 4.25 higher; low-certainty evidence). However, SSRIs may increase treatment cessations due to adverse events compared to placebo (RR, 3.80; 95% CI, 2.61-5.51; low-certainty evidence).

CONCLUSIONS

SSRI treatment for PE appears to substantially improve a number of outcomes of direct patient importance such as symptom improvement, satisfaction with intercourse and perceived control over ejaculation when compared to placebo.

[Pharmacotherapy of chronic neuropathic pain]

Chronic neuropathic pain has a prevalence of 6.9-10% in the general population. The current recommendations for treatment are presented based on a literature search. Neuropathic pain requires the use of co-analgesic, antidepressant, anticonvulsant drugs and topical agents because non-opioid analgesic drugs are usually ineffective. The use of meta-analyses tricyclic antidepressants, selective serotonin-norephinephrine reuptake inhibitors, and calcium channel anticonvulsants are recommended as the drugs of first choice. Under certain conditions chronic neuropathic pain can be treated with opioids. Topical therapeutics are only used to treat peripheral neuropathic pain. At present the use of drugs is independent of the etiology of the pain. Comorbidities, concomitant medication, potential side effects and patients' age have to be considered in treatment planning.

Validation of maternal recall of early pregnancy medication exposure using prospective diary data

PURPOSE

Data about maternal recall accuracy for classifying early pregnancy medication exposure are meager. Nonetheless, studies often rely on recall to evaluate potential impact of pharmaceuticals on the developing fetus.

METHODS

Right from the Start is a community-based pregnancy cohort that enrolled women from North Carolina, Tennessee, and Texas. A subset of 318 women participated in daily medication diaries initiated before conception (2006-2012). We examined nonsteroidal anti-inflammatory drugs (NSAIDs) as an example of a drug type that is difficult to study due to its intermittent and primarily over-the-counter use as well as its incomplete documentation in medical and pharmaceutical records. Selective serotonin reuptake inhibitors (SSRI) were assessed as a prescription medication comparator. Maternal recall of NSAID and SSRI use in early pregnancy was examined by comparing diary data (gold standard) to first-trimester interview.

RESULTS

Sensitivity and specificity for recall of NSAID exposure were 78.6% and 62.3%, respectively (kappa statistic: 0.41), with 72.3% agreement for exposure classification. Sensitivity and specificity for recall of SSRI exposure were 77.8% and 99.0%, respectively (kappa statistic: 0.79), with 97.8% agreement.

CONCLUSIONS

Our findings suggest the validity of maternal recall varies with medication type and prospective data collection should be prioritized when studying early pregnancy drug exposures.