Perceptions in orthopedic surgery on the use of cannabis in treating pain: a survey of patients with spine pain (POSIT Spine).

BACKGROUND: Back pain is the leading cause of disability worldwide. Despite guidelines discouraging opioids as first-line treatment, opioids remain the most prescribed drugs for back pain. There is renewed interest in exploring the potential medical applications of cannabis, and with the recent changes in national legislation there is a unique opportunity to investigate the analgesic properties of cannabis. METHODS: This was a multi-center survey-based study examining patient perceptions regarding cannabis for spine pain. We included patients presenting with back or neck pain to one of three Orthopedic clinics in Ontario. Our primary outcome was perceived effect of cannabis on back pain, while secondary outcomes were perceptions regarding potential applications and barriers to cannabis use. RESULTS: 259 patients participated in this study, 35.3% (90/255) stating they used cannabis medically. Average pain severity was 6.5/10 ± 0.3 (95% CI 6.2-6.8). Nearly three-quarters were prescribed opioids (73.6%, 148/201), with oxycodone/oxycontin (45.9% 68/148) being the most common, and almost half of (49.3%, 73/148) had used an opioid in the last week. Patients estimated cannabis could treat 54.3% ± 4.0 (95% CI 50.3-58.3%) of their spine pain and replace 46.2% ± 6. 6 (95% CI 39.6-52.8%) of their current analgesics. Age (ß = - 0.3, CI - 0.6-0.0), higher pain severity (ß = 0.4, CI 0.1-0.6) and previous cannabis use (ß = 14.7, CI 5.1-24.4) were associated with a higher perceived effect of cannabis. Patients thought cannabis would be beneficial to treat pain (129/146, 88.4%), and reduce (116/146, 79.5%) or eliminate opioids (102/146, 69.9%). Not considering using cannabis for medical purposes (65/150, 43.3%) was the number one reported barrier. CONCLUSIONS: Patients estimated medical cannabis could treat more than half of their spine pain, with one in three patients already using medical cannabis. 79% of patients also believe cannabis could reduce opioid usage. This data will help support more research into cannabis for musculoskeletal pain.

Safety of baclofen versus tizanidine for older adults with musculoskeletal pain.

BACKGROUND: Baclofen and tizanidine are both muscle relaxants that carry the risk for neuropsychiatric events in older adults but there is a lack of data directly comparing their safety. This study aimed to investigate the relative risk between these two medications in causing injury and delirium in older adults. METHODS: This was a retrospective cohort study that was completed in an integrated healthcare system in the United States and included patients aged 65 years or older who started baclofen or tizanidine for the treatment of musculoskeletal pain from January 2016 through December 2018. Outcomes included new incidence of injury (concussion, contusion, dislocation, fall, fracture, or other injuries) and delirium. The cohort was followed from the initiation of therapy until the first occurrence of any of the following events: end of the index drug exposure, end of health plan membership, death, or the study end date of December 31st, 2019. Descriptive statistics were used to compare baseline patient characteristics between baclofen and tizanidine treatment groups. Cox proportional hazards model was used to calculate adjusted hazard ratios (HRs) with 95% confidence intervals. RESULTS: The final study cohort included 12,101 and 6,027 older adults in the baclofen and tizanidine group respectively (mean age 72.2 ± 6.2 years old, 59% female). Older adults newly started on baclofen had a greater risk of injury (HR = 1.54, 95% CI = 1.21-1.96, P = < 0.001) and delirium (HR = 3.33, 95% CI = 2.11-5.26, p = <0.001) compared to those started on tizanidine. CONCLUSION: The results of this study suggest that baclofen is associated with higher incidences of injury and delirium compared to tizanidine when used for the treatment of musculoskeletal pain. Future studies should investigate if these risks are dose-related and include a comparison group not exposed to either drug.

Systemic therapies for preventing or treating aromatase inhibitor-induced musculoskeletal symptoms in early breast cancer.

BACKGROUND: Adjuvant aromatase inhibitors (AI) improve survival compared to tamoxifen in postmenopausal women with hormone receptor-positive stage I to III breast cancer. In approximately half of these women, AI are associated with aromatase inhibitor-induced musculoskeletal symptoms (AIMSS), often described as symmetrical pain and soreness in the joints, musculoskeletal pain and joint stiffness. AIMSS may have significant and prolonged impact on women's quality of life. AIMSS reduces adherence to AI therapy in up to a half of women, potentially compromising breast cancer outcomes. Differing systemic therapies have been investigated for the prevention and treatment of AIMSS, but the effectiveness of these therapies remains unclear. OBJECTIVES: To assess the effects of systemic therapies on the prevention or management of AIMSS in women with stage I to III hormone receptor-positive breast cancer. SEARCH METHODS: We searched CENTRAL, MEDLINE, Embase, WHO International Clinical Trials Registry Platform (ICTRP) and Clinicaltrials.gov registries to September 2020 and the Cochrane Breast Cancer Group (CBCG) Specialised Register to March 2021.  SELECTION CRITERIA: We included all randomised controlled trials that compared systemic therapies to a comparator arm. Systemic therapy interventions included all pharmacological therapies, dietary supplements, and complementary and alternative medicines (CAM). All comparator arms were allowed including placebo or standard of care (or both) with analgesia alone. Published and non-peer-reviewed studies were eligible. DATA COLLECTION AND ANALYSIS: Two review authors independently screened studies, extracted data, and assessed risk of bias and certainty of the evidence using the GRADE approach. Outcomes assessed were pain, stiffness, grip strength, safety data, discontinuation of AI, health-related quality of life (HRQoL), breast cancer-specific quality of life (BCS-QoL), incidence of AIMSS, breast cancer-specific survival (BCSS) and overall survival (OS). For continuous outcomes, we used vote-counting by reporting how many studies reported a clinically significant benefit within the confidence intervals (CI) of the mean difference (MD) between treatment arms, as determined by the minimal clinically importance difference (MCID) for that outcome scale. For dichotomous outcomes, we reported outcomes as a risk ratio (RR) with 95% CI. MAIN RESULTS: We included 17 studies with 2034 randomised participants. Four studies assessed systemic therapies for the prevention of AIMSS and 13 studies investigated treatment of AIMSS. Due to the variation in systemic therapy studies, including pharmacological, and CAM, or unavailable data, meta-analysis was limited, and only two trials were combined for meta-analysis. The certainty of evidence for all outcomes was either low or very low certainty. Prevention studies The evidence is very uncertain about the effect of systemic therapies on pain (from baseline to the end of the intervention; 2 studies, 183 women). The two studies, investigating vitamin D and omega-3 fatty acids, showed a treatment effect with 95% CIs that did not include an MCID for pain. Systemic therapies may have little to no effect on grip strength (RR 1.08, 95% CI 0.37 to 3.17; 1 study, 137 women) or on women continuing to take their AI (RR 0.16, 95% 0.01 to 2.99; 1 study, 147 women). The evidence suggests little to no effect on HRQoL and BCS-QoL from baseline to the end of intervention (the same single study; 44 women, both quality of life outcomes showed a treatment effect with 95% CIs that did include an MCID). The evidence is very uncertain for outcomes assessing incidence of AIMSS (RR 0.82, 95% CI 0.63 to 1.06; 2 studies, 240 women) and the safety of systemic therapies (4 studies, 344 women; very low-certainty evidence). One study had a US Food and Drug Administration alert issued for the intervention (cyclo-oxygenase-2 inhibitor) during the study, but there were no serious adverse events in this or any study. There were no data on stiffness, BCSS or OS. Treatment studies The evidence is very uncertain about the effect of systemic therapies on pain from baseline to the end of intervention in the treatment of AIMSS (10 studies, 1099 women). Four studies showed an MCID in pain scores which fell within the 95% CI of the measured effect (vitamin D, bionic tiger bone, Yi Shen Jian Gu granules, calcitonin). Six studies showed a treatment effect with 95% CI that did not include an MCID (vitamin D, testosterone, omega-3 fatty acids, duloxetine, emu oil, cat's claw).  The evidence was very uncertain for the outcomes of change in stiffness (4 studies, 295 women), HRQoL (3 studies, 208 women) and BCS-QoL (2 studies, 147 women) from baseline to the end of intervention. The evidence suggests systemic therapies may have little to no effect on grip strength (1 study, 107 women). The evidence is very uncertain about the safety of systemic therapies (10 studies, 1250 women). There were no grade four/five adverse events reported in any of the studies. The study of duloxetine reported more all-grade adverse events in this treatment group than comparator group. There were no data on the incidence of AIMSS, the number of women continuing to take AI, BCCS or OS from the treatment studies. AUTHORS' CONCLUSIONS: AIMSS are chronic and complex symptoms with a significant impact on women with early breast cancer taking AI. To date, evidence for safe and effective systemic therapies for prevention or treatment of AIMSS has been minimal. Although this review identified 17 studies with 2034 randomised participants, the review was challenging due to the heterogeneous systemic therapy interventions and study methodologies, and the unavailability of certain trial data. Meta-analysis was thus limited and findings of the review were inconclusive. Further research is recommended into systemic therapy for AIMSS, including high-quality adequately powered RCT, comprehensive descriptions of the intervention/placebo, and robust definitions of the condition and the outcomes being studied.

Predictors of Pain Reduction in Trials of Interventions for Aromatase Inhibitor-Associated Musculoskeletal Symptoms.

Background: Almost one-half of aromatase inhibitor (AI)-treated breast cancer patients experience AI-associated musculoskeletal symptoms (AIMSS); 20%-30% discontinue treatment because of severe symptoms. We hypothesized that we could identify predictors of pain reduction in AIMSS intervention trials by combining data from previously conducted trials. Methods: We pooled patient-level data from 3 randomized trials testing interventions (omega-3 fatty acids, acupuncture, and duloxetine) for AIMSS that had similar eligibility criteria and the same patient-reported outcome measures. Only patients with a baseline Brief Pain Inventory average pain score of at least 4 of 10 were included. The primary outcome examined was 2-point reduction in average pain from baseline to week 12. Variable cut-point selection and logistic regression were used. Risk models were built by summing the number of factors statistically significantly associated with pain reduction. Analyses were stratified by study and adjusted for treatment arm. Results: For the 583 analyzed patients, the 4 factors statistically significantly associated with pain reduction were Functional Assessment of Cancer Therapy Functional Well-Being greater than 24 and Physical Well-Being greater than 14 (higher scores reflect better function), and Western Ontario and McMaster Universities Osteoarthritis Index less than 50 and Modified Score for the Assessment and Quantification of Chronic Rheumatoid Affections of the Hands less than 33 (lower scores reflect less pain). Patients with all 4 factors were greater than 6 times more likely to experience at least a 2-point pain reduction (odds ratio = 6.37, 95% confidence interval = 2.31 to 17.53, 2-sided P < .001); similar results were found for secondary 30% and 50% pain reduction endpoints. Conclusions: Patients with AIMSS who have lower symptom and functional distress at study entry on AIMSS intervention trials are more likely to experience meaningful pain reduction. Baseline symptom and functional status should be considered as stratification factors in future interventional trials.

Involvement of Oxidative Stress and Nerve Growth Factor in Behavioral and Biochemical Deficits of Experimentally Induced Musculoskeletal Pain in Mice: Ameliorative Effects of Heraclin.

Musculoskeletal pain is a widespread complex regional pain syndrome associated with altered emotional and cognitive functioning along with heightened physical disability that has become a global health concern. Effective management of this disorder and associated disabilities includes accurate diagnosis of its biomarkers and instituting mechanism-based therapeutic interventions. Herein, we explored the role of heraclin, a plant-derived molecule, in musculoskeletal pain and its underlying mechanistic approaches in an experimental mouse model. Reserpine (0.5 mg/kg) for 3 consecutive days evoked hyperalgesia, motor incoordination, lack of exploratory behavior, anxiety, and cognition lapse in mice. Reserpine-challenged mice displayed higher serum cytokine level, altered brain neurotransmitter content, elevated brain and muscle oxidative stress, and upregulated brain nerve growth factor receptor expression. Treatment with heraclin (10 mg/kg for 5 consecutive days) exerted analgesic effect and improved motor coordination and memory deficits in mice. Heraclin arrested serum cytokine rise, normalized brain neurotransmitter content, reduced tissue oxidative stress, and downregulated the nerve growth factor receptor expression. Therefore, it may be suggested that heraclin exerts beneficial effects against reserpine-induced musculoskeletal pain disorder possibly through the attenuation of NGFR-mediated pain and inflammatory signaling. Graphical Abstract.

Complementary and alternative medicine and musculoskeletal pain in the first year of adjuvant aromatase inhibitor treatment in early breast cancer patients.

BACKGROUND: Patients with breast cancer (BC) show strong interest in complementary and alternative medicine (CAM), particularly for adverse effects of adjuvant endocrine treatment - e.g., with letrozole. Letrozole often induces myalgia/limb pain and arthralgia, with potential noncompliance and treatment termination. This analysis investigated whether CAM before aromatase inhibitor (AI) therapy is associated with pain development and the intensity of AI-induced musculoskeletal syndrome (AIMSS) during the first year of treatment. PATIENTS AND METHODS: The multicenter phase IV PreFace study evaluated letrozole therapy in postmenopausal, hormone receptor-positive patients with early BC. Patients were asked about CAM use before, 6 months after, and 12 months after treatment started. They recorded pain every month for 1 year in a diary including questions about pain and numeric pain rating scales. Data were analyzed for patients who provided pain information for all time points. RESULTS: Of 1396 patients included, 901 (64.5%) had used CAM before AI treatment. Throughout the observation period, patients with CAM before AI treatment had higher pain values, for both myalgia/limb pain and arthralgia, than non-users. Pain increased significantly in both groups over time, with the largest increase during the first 6 months. No significant difference of pain increase was noted regarding CAM use. CONCLUSIONS: CAM use does not prevent or improve the development of AIMSS. Pain intensity was generally greater in the CAM group. Therefore, because of the risk of non-compliance and treatment discontinuation due to the development of higher pain levels, special attention must be paid to patient education and aftercare in these patients.

Involvement of Substance P in the Analgesic Effect of Low-Level Laser Therapy in a Mouse Model of Chronic Widespread Muscle Pain.

BACKGROUND: Low-level laser therapy (LLLT) is widely used in pain control in the field of physical medicine and rehabilitation and is effective for fibromyalgia pain. However, its analgesic mechanism remains unknown. A possible mechanism for the effect of LLLT on fibromyalgia pain is via the antinociceptive signaling of substance P in muscle nociceptors, although the neuropeptide has been known as a neurotransmitter to facilitate pain signals in the spinal cord. OBJECTIVE: To establish an animal model of LLLT in chronic muscle pain and to determine the role of substance P in LLLT analgesia. METHODS: We employed the acid-induced chronic muscle pain model, a fibromyalgia model proposed and developed by Sluka et al., and determined the optimal LLLT dosage. RESULTS: LLLT with 685 nm at 8 J/cm2 was effective to reduce mechanical hyperalgesia in the chronic muscle pain model. The analgesic effect was abolished by pretreatment of NK1 receptor antagonist RP-67580. Likewise, LLLT showed no analgesic effect on Tac1-/- mice, in which the gene encoding substance P was deleted. Besides, pretreatment with the TRPV1 receptor antagonist capsazepine, but not the ASIC3 antagonist APETx2, blocked the LLLT analgesic effect. CONCLUSIONS: LLLT analgesia is mediated by the antinociceptive signaling of intramuscular substance P and is associated with TRPV1 activation in a mouse model of fibromyalgia or chronic muscle pain. The study results could provide new insight regarding the effect of LLLT in other types of chronic pain.

A combination of hydroxytyrosol, omega-3 fatty acids and curcumin improves pain and inflammation among early stage breast cancer patients receiving adjuvant hormonal therapy: results of a pilot study.

PURPOSE: Breast cancer patients receiving hormonal therapies face risks of relapse, increased rates of cardiovascular events, and toxicities of therapy such as aromatase inhibitor (AI)-associated musculoskeletal symptoms (AIMSS). C-reactive protein (CRP), a marker for inflammation, is associated with breast cancer outcomes. We evaluated whether the olive-derived polyphenol hydroxytyrosol combined with omega-3 fatty acids and curcumin would reduce CRP and musculoskeletal symptoms in breast cancer patients receiving adjuvant hormonal therapies. EXPERIMENTAL DESIGN: This prospective, multicenter, open-label, single arm, clinical trial enrolled post-menopausal breast cancer patients (n = 45) with elevated C-reactive protein (CRP) taking predominantly aromatase inhibitors to receive a combination of hydroxytyrosol, omega-3 fatty acids, and curcumin for 1 month. CRP, other inflammation-associated cytokines, and pain scores on the Brief Pain Inventory were measured before therapy, at the end of therapy and 1 month after completion of therapy. RESULTS: CRP levels declined during the therapy [from 8.2 ± 6.4 mg/L at baseline to 5.3 ± 3.2 mg/L (p = 0.014) at 30 days of treatment], and remained decreased during the additional 1 month off therapy. Subjects with the highest baseline CRP levels had the greatest decrease with the therapy. Pain scores also decreased during the therapy. There were no significant adverse events. CONCLUSIONS: The combination of hydroxytyrosol, omega-3 fatty acids, and curcumin reduced inflammation as indicated by a reduction in CRP and reduced pain in patients with aromatase-induced musculoskeletal symptoms. Longer studies comparing this combination to other anti-inflammatories in larger groups of patients with clinical outcome endpoints are warranted.

Randomized placebo-controlled pilot trial of omega 3 fatty acids for prevention of aromatase inhibitor-induced musculoskeletal pain.

PURPOSE: Aromatase inhibitor (AI)-induced joint symptoms negatively impact drug adherence and quality of life in breast cancer survivors. Mechanisms underlying symptoms may include inflammation. It is hypothesized that n - 3 polyunsaturated fatty acids (PUFAs) have anti-inflammatory properties and may reduce symptoms. METHODS: We conducted a randomized, double-blind, placebo-controlled study comparing 4.3 g/day n - 3 PUFA supplements vs placebo for 24 weeks in postmenopausal breast cancer patients starting adjuvant AIs. Primary endpoints were adherence and tolerability; secondary outcomes included inflammatory cytokines and symptoms assessed by the Brief Pain Inventory short form (BPI-SF) and Functional Assessment of Cancer Treatment-Endocrine Symptoms (FACT-ES) at 0, 12, and 24 weeks. RESULTS: Forty-four women were randomized, of which 35 completed the study. Adherence was ≥ 88% based on these 35 patients with pill counts as well as change in red blood cell (RBC) n - 3 PUFAs. Common toxicities included grade 1 flatulence (55% of both groups) and belching (45% of n - 3 group). Mean pain severity scores (BPI-SF) did not change significantly by time or treatment arm. Quality of life, based on FACT-ES scores, significantly decreased within placebo (p = 0.04), but not the n - 3 group (p = 0.58), with a trend toward between-group differences (p = 0.06) at 12 weeks, but no significant differences at 24 weeks. RBC n - 3 levels were strongly positively correlated with FACT-ES at 12 weeks, but attenuated at 24 weeks. CONCLUSION: High-dose n - 3 PUFA supplementation is feasible and well tolerated when administered with AIs. Additional studies are needed to evaluate efficacy in prevention of joint symptoms.

Effects of the Chinese medicine Yi Shen Jian Gu granules on aromatase inhibitor-associated musculoskeletal symptoms: A randomized, controlled clinical trial.

Aromatase inhibitor-associated musculoskeletal symptoms (AIMSS) are prevalent among patients on AI therapy, which leads to a lower quality of life and poor adherence to AI treatment. We evaluated whether Yi Shen Jian Gu granules (YSJG) is effective and safe to relieve AIMSS in patients with breast cancer. Eligible participants were randomly assigned to the YSJG group or the placebo group. Both groups had a 12-week treatment period and a 12-week follow-up period. Brief Pain Inventory-Short Form (BPI-SF), Western Ontario and McMaster Universities Osteoarthritis (WOMAC) Index, and the Modified Score for the Assessment and Quantification of Chronic Rheumatoid Affections of the Hands (M-SACRAH) were obtained at baseline and at 4, 8, 12 and 24 weeks. Of 146 participants enrolled, 84 were randomly assigned, and 77 were evaluable at 12 weeks. Baseline characteristics were comparable between two groups. The primary outcome was the differences in mean BPI-SF scores at 12 weeks. The worst pain scores decreased by 3.10 points (50.2%; 95% CI, 2.50 to 3.65) for YSJG group compared with a 1.63-point decrease (26.9%; 95% CI, 3.86 to 4.97) for the placebo group (P = 0.001). Significantly improvements were also observed for the WOMAC and M-SACRAH. Possibly YSJG-related side effects were grade 1 nausea (10%) and grade 2 diarrhea (2%). Serum follicle-stimulating hormone and serum estradiol were kept in the postmenopausal range before and after YSJG treatment. Patients with AIMSS treated with YSJG granules had significant improvements in musculoskeletal symptoms. YSJG is effective, safe and well-tolerated in managing AIMSS. TRIAL REGISTRATION: ISCTN: ISRCTN06129599 (assigned 14 August 2013).

Randomized trial of vitamin D3 to prevent worsening of musculoskeletal symptoms in women with breast cancer receiving adjuvant letrozole. The VITAL trial.

PURPOSE: Aromatase inhibitor-associated musculoskeletal symptoms (AIMSS) frequently occur in women being treated for breast cancer. Prior studies suggest high prevalence of vitamin D deficiency in breast cancer patients with musculoskeletal (MS) pain. We conducted a randomized, placebo-controlled trial to determine if 30,000 IU vitamin D3 per week (VitD3) would prevent worsening of AIMSS in women starting adjuvant letrozole for breast cancer. METHODS: Women with stage I-III breast cancer starting adjuvant letrozole and 25(OH)D level ≤40 ng/ml were eligible. All subjects received standard daily supplement of 1200 mg calcium and 600 IU vitamin D3 and were randomized to 30,000 IU oral VitD3/week or placebo. Pain, disability, fatigue, quality of life, 25(OH)D levels, and hand grip strength were assessed at baseline, 12, and 24 weeks. The primary endpoint was incidence of an AIMSS event. RESULTS: Median age of the 160 subjects (80/arm) was 61. Median 25OHD (ng/ml) was 25 at baseline, 32 at 12 weeks, and 31 at 24 weeks in the placebo arm and 22, 53, and 57 in the VitD3 arm. There were no serious adverse events. At week 24, 51% of women assigned to placebo had a protocol defined AIMSS event (worsening of joint pain using a categorical pain intensity scale (CPIS), disability from joint pain using HAQ-II, or discontinuation of letrozole due to MS symptoms) vs. 37% of women assigned to VitD3 (p = 0.069). When the brief pain inventory (BPI) was used instead of CPIS, the difference was statistically significant: 56 vs. 39% (p = 0.024). CONCLUSIONS: Although 30,000 IU/week of oral vitamin D3 is safe and effective in achieving adequate vitamin D levels, it was not associated with a decrease in AIMSS events based on the primary endpoint. Post-hoc analysis using a different tool suggests potential benefit of vitamin D3 in reducing AIMSS.

D-limonene exhibits superior antihyperalgesic effects in a ß-cyclodextrin-complexed form in chronic musculoskeletal pain reducing Fos protein expression on spinal cord in mice.

Chronic musculoskeletal pain is one of the main symptoms found in Fibromyalgia with unclear etiology and limited pharmacological treatment. The aim of this study was to complex LIM in ß-cyclodextrin (LIM-ßCD) and then evaluate its antihyperalgesic effect in an animal model of chronic musculoskeletal pain. Differential scanning calorimetry and scanning electron microscopy was used for the characterization of the inclusion complex. Male Swiss mice were used for experimental procedures where mechanical hyperalgesia, thermal hyperalgesia, muscular strength, Fos immunofluorescence was studied after induction of hyperalgesia. Mechanism of action was also investigated through tail flick test and capsaicin-induced nociception. Endothermic events and morphological changes showed that the slurry complex method was the best method for the complexation. After induction of hyperalgesia, the oral administration of LIM-ßCD (50mg/kg) significantly increased the paw withdrawal threshold compared to uncomplexed limonene. Fos immunofluorescence showed that both compounds significantly decreased the number of Fos-positive cells in the dorsal horn. In nociceptive tests, FLU was able to reverse the antinociceptive effect of LIM-ßCD. After intraplantar administration of capsaicin, LIM was able to significantly decrease time to lick. LIM-ßCD has antihyperalgesic action superior to its uncomplexed form, with possible action in the dorsal horn of the spinal cord. These results suggest the possible applicability of LIM, uncomplexed or complexed with ßCD, in conditions such as FM and neuropathic pain, for which there are currently only limited pharmacological options.

Randomized Multicenter Placebo-Controlled Trial of Omega-3 Fatty Acids for the Control of Aromatase Inhibitor-Induced Musculoskeletal Pain: SWOG S0927.

PURPOSE: Musculoskeletal symptoms are the most common adverse effects of aromatase inhibitors (AIs) and can result in decreased quality of life and discontinuation of therapy. Omega-3 fatty acids (O3-FAs) can be effective in decreasing arthralgia resulting from rheumatologic conditions and reducing serum triglycerides. PATIENTS AND METHODS: Women with early-stage breast cancer receiving an AI who had a worst joint pain/stiffness score ≥ 5 of 10 using the Brief Pain Inventory-Short Form (BPI-SF) were randomly assigned to receive either O3-FAs 3.3 g or placebo (soybean/corn oil) daily for 24 weeks. Clinically significant change was defined as ≥ 2-point drop from baseline. Patients also completed quality-of-life (Functional Assessment of Cancer Therapy-Endocrine Symptoms) and additional pain/stiffness assessments at baseline and weeks 6, 12, and 24. Serial fasting blood was collected for lipid analysis. RESULTS: Among 262 patients registered, 249 were evaluable, with 122 women in the O3-FA arm and 127 in the placebo arm. Compared with baseline, the mean observed BPI-SF score decreased by 1.74 points at 12 weeks and 2.22 points at 24 weeks with O3-FAs and by 1.49 and 1.81 points, respectively, with placebo. In a linear regression adjusting for the baseline score, osteoarthritis, and taxane use, adjusted 12-week BPI-SF scores did not differ by arm (P = .58). Triglyceride levels decreased in patients receiving O3-FA treatment and remained the same for those receiving placebo (P = .01). No between-group differences were seen for HDL, LDL, or C-reactive protein. CONCLUSION: We found a substantial (> 50%) and sustained improvement in AI arthralgia for both O3-FAs and placebo but found no meaningful difference between the groups.

A dual-center randomized controlled double blind trial assessing the effect of acupuncture in reducing musculoskeletal symptoms in breast cancer patients taking aromatase inhibitors.

Up to 50 % of women receiving aromatase inhibitor (AI) complain of AI-associated musculoskeletal symptoms (AIMSS) and 15 % discontinue treatment. We conducted a randomized, sham-controlled trial to evaluate whether acupuncture improves AIMSS and to explore potential mechanisms. Postmenopausal women with early stage breast cancer, experiencing AIMSS were randomized to eight weekly real or sham acupuncture sessions. We evaluated changes in the Health Assessment Questionnaire Disability Index (HAQ-DI) and pain visual analog scale (VAS) following the intervention compared to baseline. Serum estradiol, ß-endorphin, and proinflammatory cytokine concentrations were measured pre and post-intervention. We enrolled 51 women of whom 47 were evaluable, including 23 randomized to real and 24 to sham acupuncture. Baseline characteristics were balanced between groups with the exception of a higher HAQ-DI score in the real acupuncture group (p = 0.047). We did not observe a statistically significant difference in reduction of HAQ-DI (p = 0.30) or VAS (p = 0.31) between the two groups. Following eight weekly treatments, we observed a statistically significant reduction of IL-17 (p ≤ 0.009) in both groups. No significant modulation was seen in estradiol, ß-endorphin, or other proinflammatory cytokine concentrations in either group. We did not observe a significant difference in AIMSS changes between real and sham acupuncture. As sham acupuncture used in this study may not be equivalent to placebo, further studies with a non-acupuncture arm may be required to establish whether acupuncture is beneficial for the treatment of AIMSS.

Effect of statins on skeletal muscle function.

BACKGROUND: Many clinicians believe that statins cause muscle pain, but this has not been observed in clinical trials, and the effect of statins on muscle performance has not been carefully studied. METHODS AND RESULTS: The Effect of Statins on Skeletal Muscle Function and Performance (STOMP) study assessed symptoms and measured creatine kinase, exercise capacity, and muscle strength before and after atorvastatin 80 mg or placebo was administered for 6 months to 420 healthy, statin-naive subjects. No individual creatine kinase value exceeded 10 times normal, but average creatine kinase increased 20.8±141.1 U/L (P<0.0001) with atorvastatin. There were no significant changes in several measures of muscle strength or exercise capacity with atorvastatin, but more atorvastatin than placebo subjects developed myalgia (19 versus 10; P=0.05). Myalgic subjects on atorvastatin or placebo had decreased muscle strength in 5 of 14 and 4 of 14 variables, respectively (P=0.69). CONCLUSIONS: These results indicate that high-dose atorvastatin for 6 months does not decrease average muscle strength or exercise performance in healthy, previously untreated subjects. Nevertheless, this blinded, controlled trial confirms the undocumented impression that statins increase muscle complaints. Atorvastatin also increased average creatine kinase, suggesting that statins produce mild muscle injury even among asymptomatic subjects. This increase in creatine kinase should prompt studies examining the effects of more prolonged, high-dose statin treatment on muscular performance. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT00609063.

High-dose isotretinoin in acne vulgaris: improved treatment outcomes and quality of life.

BACKGROUND: Isotretinoin, for acne treatment, is associated with high rates of permanent remission. However, at recommended doses of 0.5-1.0 mg/kg/day for 5-6 months [average cumulative dose: 120-150 mg/kg], more than 20% of patients experience a relapse within two years that requires further medical management. OBJECTIVE: To examine outcomes of high-dose isotretinoin in a cohort with cystic acne, as well as measuring its impact on quality of life (QOL). METHODS: A single dermatologist, single institution investigation within an academic tertiary care center in Bronx, NY. Eighty patients with nodulocystic acne, maintained on oral isotretinoin at a dose of 1.3 mg/kg/day or greater, were studied from 2006-2009 while additionally participating in a QOL survey. Main outcome measures included documented events, acne clearance, presence of relapse, and quality of life parameters. RESULTS: The mean daily dose of isotretinoin was 1.6 mg/kg/day for an average time course of 178 days [cumulative dose: 290 mg/kg]. No side effects or laboratory abnormalities led to discontinuation of treatment. There were no psychiatric symptoms. One-hundred percent (100%) of patients were disease-free upon completion of treatment. During the three-year study period, 10 patients (12.5%) developed a relapse that required an additional course of isotretinoin. Analysis of QOL domains (self-perception, role-social, symptoms) revealed significant improvement following isotretinoin therapy (p = 0.0124, p = 0.0066, p = 0.0265, respectively). CONCLUSIONS: Isotretinoin prescribed at 1.5 mg/kg/day or greater for 5-6 months [cumulative total dose of 290 mg/kg] is safe and effective compared to current standard dosing practices. We propose the use of high-dose isotretinoin (>1.3 mg/kg/day) as a treatment option in severe nodulocystic acne and encourage larger, prospective, multicenter studies into this therapeutic approach.

Muscle pain and serum creatine kinase are not associated with low serum 25(OH) vitamin D levels in patients receiving statins.

OBJECTIVE: Vitamin D deficiency has been associated in some studies with nonspecific musculoskeletal pain and, more specifically, with statin-induced myalgia, which was ameliorated by high-dose vitamin D supplements. Our objective was to explore the association between vitamin D status and statin-induced myalgia and elevation of serum creatine kinase (CK). DESIGN: Retrospective cohort study, based on the electronic database of a health maintenance organization. PATIENTS: Six thousand eight hundred and eight patients (71·5% women) to whom statins were dispensed during 2008 and who had ≥1 CK and 25-hydroxy vitamin D (25OHD) levels measured during statin exposure. Of these, 376 patients (5·5%) had switched from a first-line statin to atorvastatin because of muscle pain (n = 220) or other reasons (n = 156). Measurements; In the entire cohort, we compared serum CK levels among serum 25OHD quartiles. In addition, we compared CK and 25OHD levels among patients with myalgia, other switchers and nonswitchers. RESULTS: The median 25OHD level in the entire cohort was 21·8 ng/ml [interquartile range (IQR), 16·3-27·4]. CK levels were marginally lower in patients in the lowest 25OHD quartile [median CK (IQR) in 25OHD quartiles 1-4, 87 (61-130), 90 (65-131), 91 (65-132) and 91 (67-131) IU/ml, respectively; P = 0·007]. 25OHD levels in statin switchers were similar to those in nonswitchers; moreover, there were no differences in 25OHD among switchers with muscle pain and other switchers. CONCLUSION: Our findings do not support an association between low 25OHD levels and statin-induced myalgia or CK elevation.

An antinociceptive role for substance P in acid-induced chronic muscle pain.

Release of substance P (SP) from nociceptive nerve fibers and activation of its receptor neurokinin 1 (NK1) are important effectors in the transmission of pain signals. Nonetheless, the role of SP in muscle pain remains unknown. Here we show that a single i.m. acid injection in mice lacking SP signaling by deletion of the tachykinin precursor 1 (Tac1) gene or coadministration of NK1 receptor antagonists produces long-lasting hyperalgesia rather than the transient hyperalgesia seen in control animals. The inhibitory effect of SP was found exclusively in neurons expressing acid-sensing ion channel 3, where SP enhances M-channel-like potassium currents through the NK1 receptor in a G protein-independent but tyrosine kinase-dependent manner. Furthermore, the SP signaling could alter action potential thresholds and modulate the expression of TTX-resistant sodium currents in medium-sized muscle nociceptors. Thus, i.m. SP mediates an unconventional NK1 receptor signal pathway to inhibit acid activation in muscle nociceptors, resulting in an unexpected antinociceptive effect against chronic mechanical hyperalgesia, here induced by repeated i.m. acid injection.