Efficacy of neuromodulation on the treatment of fibromyalgia: A network meta-analysis.

OBJECTIVE: Several types of neuromodulation have been investigated for the treatment of fibromyalgia, but they show varied efficacy on pain, functioning, comorbid depression and comorbid anxiety. Whether some types of neuromodulation or some factors are associated with a better response also awaits clarification. METHODS: We conducted a systematic review and network meta-analysis of randomized controlled trials to evaluate the efficacy of neuromodulation in patients with fibromyalgia. We searched PubMed, EMBASE, the Cochrane Central Register of Controlled Trials and PsycINFO before March 2022. We employed a frequentist random-effects network meta-analysis. RESULTS: Forty trials involving 1541 participants were included. Compared with sham control interventions, several types of transcranial direct current stimulation (tDCS), transcranial random noise stimulation (tRNS), and high-frequency repetitive transcranial magnetic stimulation (rTMS) were associated with significant reduction of pain, depression, anxiety, and improvement in functioning. Many significantly effective treatment options involve stimulation of the primary motor cortex or dorsolateral prefrontal cortex. CONCLUSION: We concluded that several types of rTMS, tDCS and tRNS may have the potential to be applied for clinical purposes.

Treating fibromyalgia with electrical neuromodulation: A systematic review and meta-analysis.

OBJECTIVE: Several types of electrical neuromodulation (such as transcranial direct current stimulation, tDCS; transcutaneous electrical nerve stimulation) have been applied in the treatment of fibromyalgia. These trials had different outcome measurements, such as subjective pain, pain threshold, depression, anxiety, and functioning. We intended to integrate data from different trials into a meta-analysis to clearly present the clinical value of electrical neuromodulation in fibromyalgia. METHODS: A systematic review and meta-analysis of randomized controlled trials comparing the effect of all types of electrical neuromodulation in patients with fibromyalgia was conducted. The main outcome was subjective pain; the secondary outcomes included depression, anxiety, and functioning. RESULTS: Twenty-five studies and 1061 fibromyalgia patients were included in the quantitative analysis. Active electrical neuromodulation and active tDCS both showed significant effects on subjective pain, depression, and functioning. For different anode tDCS electrode positions, only F3-F4 revealed a significant effect on depression. Meta-regression tDCS effects on depression were significantly associated with age. CONCLUSIONS: Electrical neuromodulation is significantly effective in treating pain, depression, and functioning in patients with fibromyalgia. SIGNIFICANCE: The results may help clinicians to arrange effective treatment plans for patients with fibromyalgia, especially in those patients who reveal limited response to pharmacotherapy and psychotherapy.

Pharmacokinetics of olanzapine in Chinese male schizophrenic patients with various smoking behaviors.

Tobacco consumption has been recognized as a factor mediating the interindividual variations in olanzapine's pharmacokinetics and pharmacodynamics. The primary objective of this study was to describe the dose effect of smoking on the dose-plasma concentration relationship and the pharmacokinetics of oral olanzapine in male schizophrenic patients using high-performance liquid chromatography coupled with electrochemical detector. Twenty-seven male schizophrenic inpatients were recruited and were stratified into the following groups according to smoking behaviors: non-smokers (n=9), light-smokers (1-4 cigarettes per day; n=9), and heavy-smokers (>or=5 cigarettes per day; n=9). Plasma olanzapine concentrations were determined up to 120 h following a single oral dose of 10 mg olanzapine. The pharmacokinetic parameters were calculated by the non-compartment method using WinNonlin software. Results show that there was a significant correlation among non-smokers (n=9; 0.79; p=0.01) or combined with light-smokers (n=18; 0.62; p<0.01) between peak plasma olanzapine concentrations (Cmax) and their individual dose-corrected by body weight, but this correlation did not appear in heavy-smokers. There were no significant differences between non-smokers and light-smokers except for significant decreased AUC0-->120 by 45.1% in light-smokers. The mean C(max) and the mean area under the plasma concentration-time curve from time zero to 120 h (AUC0-->120) of the heavy-smoking patients was 9.3+/-4.3 ng/ml (65.2% reduction compared to the non-smokers) and 302.4+/-167.8 h ng/ml (67.6% reduction compared to the non-smokers), respectively. In summary, a daily consumption of 5 cigarettes is probably sufficient for induction of olanzapine metabolism. Smoking cessation is recommended for olanzapine therapy to have better prediction for therapeutic dosages particularly in heavy-smokers. Compared to non-smokers, heavy-smokers therefore require a 50-100% increase in olanzapine doses. Therapeutic drug monitoring will need to be considered when schizophrenic patients change their smoking behaviors.

Dose-dependent alternations in the pharmacokinetics of olanzapine during coadministration of fluvoxamine in patients with schizophrenia.

Olanzapine, an atypical antipsychotic agent, is a substrate of the cytochrome P4501A2 (CYP1A2) enzyme. Administration of a potent CYP1A2 inhibitor (eg, fluvoxamine) may alter the pharmacokinetics of olanzapine. This study investigated the pharmacokinetic interactions between olanzapine and fluvoxamine in patients with schizophrenia. Ten male smokers were administrated a single dose of olanzapine 10 mg at baseline, followed by 2 weeks of fluvoxamine 50 mg/day and another 2 weeks of fluvoxamine 100 mg/day. Olanzapine 10 mg was given at day 10 during each fluvoxamine treatment. After pretreatment with fluvoxamine, the area under the curve, maximal plasma concentration, and half-time of olanzapine were significantly increased by 30% to 55%, 12% to 64%, and 25% to 32%, respectively. Volume of distribution and apparent clearance were significantly reduced by 4% to 26% and 26% t O 38%, respectively, after administration of fluvoxamine. Increases in area under the plasma concentration-time curve from time 0 to infinity appear to be dose dependent. Presumably, altered olanzapine pharmacokinetics are attributed to the inhibition of CYP1A2. Patients treated with the combination of olanzapine and fluvoxamine should be monitored carefully.

Heavy smoking, reduced olanzapine levels, and treatment effects: a case report.

A 30-year-old schizophrenic male patient, a heavy smoker, was successfully treated with olanzapine 15 mg/d during hospitalization. His cigarette consumption increased rapidly from 12 to 80 cigarettes per day following his discharge. Ten days later, his delusion of persecution, levels of hostility, and aggressive behavior worsened, while the plasma levels of olanzapine concurrently decreased. Based on our observations of this case, we suggest that the reduced levels of plasma olanzapine and exacerbated clinical symptoms are closely related to the increased consumption of cigarettes. A possible explanation would be that heavy smoking induced cytochrome P4501A2, the major enzyme involved in olanzapine metabolism. Therefore, patients who smoke should be closely monitored for their cigarette consumption when the dosage of olanzapine is adjusted.

Polyunsaturated fatty acid deficit in patients with bipolar mania.

The aim of this study is to test the hypothesis that there is a depletion of polyunsaturated fatty acids of erythrocyte membranes in patients with bipolar disorder and to connect the previous therapeutic and psychoimmunological findings. Fatty acid compositions of erythrocyte membranes in 20 bipolar manic patients and 20 healthy controls were analyzed by thin-layer chromatography and gas chromatography. The major finding was significantly reduced arachidonic acid (20:4n-6) and docosahexaenoic acid (22:6n-3) compositions in bipolar patients as compared to normal controls with P values of 0.000 and 0.002, respectively. There were no differences in total omega-3 and omega-6 polyunsaturated fatty acids. This abnormality may be related to the mechanisms of action of mood stabilizers and the previous findings on the abnormal psychoimmunology of patients with bipolar disorder. Larger sample sizes of medicated patients or drug-free manic, well-controlled designs on the diet and smoking, and fatty acid composition measurements during full remission after the index episode are warranted in future studies.