Thalamic Dorsomedial Nucleus Free Water Correlates with Cognitive Decline in Parkinson's Disease.

BACKGROUND: Brain diffusion tensor imaging (DTI) has been shown to reflect cognitive changes in early Parkinson's disease (PD) but the diffusion-based measure free water (FW) has not been previously assessed. OBJECTIVES: To assess if FW in the thalamic nuclei primarily involved with cognition (ie, the dorsomedial [DMN] and anterior [AN] nuclei), the nucleus basalis of Meynert (nbM), and the hippocampus correlates with and is associated with longitudinal cognitive decline and distinguishes cognitive status at baseline in early PD. Also, to explore how FW compares with conventional DTI, FW-corrected DTI, and volumetric assessments for these outcomes. METHODS: Imaging data and Montreal Cognitive Assessment (MoCA) scores from the Parkinson's Progression Markers Initiative database were analyzed using partial correlations and ANCOVA. Primary outcome multiple comparisons were corrected for false discovery rate (q value). RESULTS: Thalamic DMN FW changes over 1 year correlated with MoCA changes over both 1 and 3 years (partial correlations -0.222, q = 0.040, n = 130; and - 0.229, q = 0.040, n = 123, respectively; mean PD duration at baseline = 6.85 months). NbM FW changes over 1 year only correlated with MoCA changes over 3 years (-0.222, q = 0.040). Baseline hippocampal FW was associated with cognitive impairment at 3 years (q = 0.040) and baseline nbM FW distinguished PD-normal cognition (MoCA ≥26) from PD-cognitive impairment (MoCA ≤25), (q = 0.008). The exploratory comparisons showed FW to be the most robust assessment modality for all outcomes. CONCLUSIONS: Thalamic DMN FW is a promising cognition progression biomarker in early PD that may assist in identifying cognition protective therapies in clinical trials. FW is a robust assessment modality for these outcomes. © 2021 International Parkinson and Movement Disorder Society.

Molecular Features of Parkinson's Disease in Patient-Derived Midbrain Dopaminergic Neurons.

BACKGROUND: Despite intense efforts to develop an objective diagnostic test for Parkinson's disease, there is still no consensus on biomarkers that can accurately diagnose the disease. OBJECTIVE: Identification of biomarkers for idiopathic Parkinson's disease (PD) may enable accurate diagnosis of the disease. We tried to find molecular and cellular differences in dopaminergic (DA) neurons derived from healthy subjects and idiopathic PD patients with or without rest tremor at onset. METHODS: We measured the expression of genes controlling dopamine synthesis, sequestration, and catabolism as well as the levels of corresponding metabolites and reactive oxygen species in midbrain DA neurons differentiated from induced pluripotent stem cells (iPSCs) of healthy subjects and PD patients with or without rest tremor. RESULTS: Significant differences in DA-related gene expression, metabolites, and oxidative stress were found between midbrain DA neurons derived from healthy subjects and patients with PD. DA neurons derived from PD patients with or without rest tremor at onset exhibited significant differences in the levels of some of these transcripts, metabolites, and oxidative stress. CONCLUSION: The unique combination of these quantifiable molecular and cellular traits in iPSC-derived midbrain DA neurons can distinguish healthy subjects from idiopathic PD patients and segregate PD patients with or without rest tremor at onset. The strategy may be used to develop an objective diagnostic test for PD.

Diffusion Magnetic Resonance Imaging Detects Progression in Parkinson's Disease: A Placebo-Controlled Trial of Rasagiline.

BACKGROUND: Rasagiline has received attention as a potential disease-modifying therapy for Parkinson's disease (PD). Whether rasagiline is disease modifying remains in question. OBJECTIVE: The main objective of this study was to determine whether rasagiline has disease-modifying effects in PD over 1 year. Secondarily we evaluated two diffusion magnetic resonance imaging pulse sequences to determine the best sequence to measure disease progression. METHODS: This prospective, randomized, double-blind, placebo-controlled trial assessed the effects of rasagiline administered at 1 mg/day over 12 months in early-stage PD. The primary outcome was 1-year change in free-water accumulation in posterior substantia nigra (pSN) measured using two diffusion magnetic resonance imaging pulse sequences, one with a repetition time (TR) of 2500 ms (short TR; n = 90) and one with a TR of 6400 ms (long TR; n = 75). Secondary clinical outcomes also were assessed. RESULTS: Absolute change in pSN free-water accumulation was not significantly different between groups (short TR: P = 0.346; long TR: P = 0.228). No significant differences were found in any secondary clinical outcomes between groups. Long TR, but not short TR, data show pSN free-water increased significantly over 1 year (P = 0.025). Movement Disorder Society Unified Parkinson's Disease Rating Scale testing of motor function, Part III increased significantly over 1 year (P = 0.009), and baseline free-water in the pSN correlated with the 1-year change in Movement Disorder Society Unified Parkinson's Disease Rating Scale testing of motor function, Part III (P = 0.004) and 1-year change in bradykinesia score (P = 0.044). CONCLUSIONS: We found no evidence that 1 mg/day rasagiline has a disease-modifying effect in PD over 1 year. We found pSN free-water increased over 1 year, and baseline free-water relates to clinical motor progression, demonstrating the importance of diffusion imaging parameters for detecting and predicting PD progression. © 2021 International Parkinson and Movement Disorder Society.

Ventral posterior substantia nigra iron increases over 3 years in Parkinson's disease.

BACKGROUND: Parkinson's disease (PD) is characterized in part by the progressive accumulation of iron within the substantia nigra (SN); however, its spatial and temporal dynamics remain relatively poorly understood. OBJECTIVES: The objective of this study was to investigate spatial patterns and temporal evolution of SN iron accumulation in PD. METHODS: A total of 18 PD patients (mean disease duration = 6.2 years) receiving dopaminergic therapy and 16 healthy controls were scanned with 3T MRI at baseline and 3 years later using quantitative susceptibility mapping, an indirect marker of iron content. Iron was assessed separately in the posterior SN and anterior SN at the ventral and dorsal levels of the SN. The results were corrected for the false discovery rate. RESULTS: A significant group effect was found for the ventral posterior SN (P < .001) and anterior SN (P = .042) quantitative susceptibility mapping as well as significant group x time interaction effects (P = .02 and P = .043, respectively). In addition, a significant intragroup change during 3 years of follow-up was found only in the ventral posterior SN of PD (P = .012), but not healthy controls. No significant effects were detected for any dorsal SN measures. No associations were identified with clinical measures. CONCLUSIONS: We found both cross-sectional and longitudinal SN iron changes to be confined to its more ventral location in PD. Because pathology studies also show the ventral SN to degenerate early and to the greatest extent in PD, the assessment of iron levels by quantitative susceptibility mapping in this area may potentially represent a disease progression biomarker in PD. © 2019 International Parkinson and Movement Disorder Society.

Gabapentin's anti-nausea and anti-emetic effects: a review.

Gabapentin's main clinical use is in the treatment of neuropathic pain where its binding to neuronal alpha-2/delta subunits of voltage-gated calcium channels (VGCCs) is critical to its mechanism of action. Over the past 10 years, there have been several reports of gabapentin also having anti-nausea and anti-emetic effects in conditions including postoperative nausea and vomiting (PONV), chemotherapy-induced nausea and vomiting (CINV), and hyperemesis gravidarum (HG). In this report, a MEDLINE electronic search was performed, and relevant citations were reviewed and classified by level of evidence; a grade of recommendation was then assigned for gabapentin's use for each studied indication. Out of 33 clinical trials reviewed, 12 assessed nausea and/or vomiting (N/V) associated with gabapentin therapy as primary outcome measures. These 12 studies provided a Grade A recommendation for gabapentin use in treating PONV, a Grade B recommendation for use in treating CINV, and a Grade C recommendation for use in treating HG. Further research is needed to confirm these initial promising results, which implicate the alpha-2/delta VGCC subunit as a novel therapeutic target in the treatment of several N/V-associated clinical conditions.

Lithium's effects on therapeutic targets and MRI biomarkers in Parkinson's disease: A pilot clinical trial.

Background: Lithium has a wide range of neuroprotective actions, has been effective in Parkinson's disease (PD) animal models and may account for the decreased risk of PD in smokers. Methods: This open-label pilot clinical trial randomized 16 PD patients to "high-dose" (n = 5, lithium carbonate titrated to achieve serum level of 0.4-0.5 mmol/L), "medium-dose" (n = 6, 45 mg/day lithium aspartate) or "low-dose" (n = 5, 15 mg/day lithium aspartate) lithium therapy for 24-weeks. Peripheral blood mononuclear cell (PBMC) mRNA expression of nuclear receptor-related-1 (Nurr1) and superoxide dismutase-1 (SOD1) were assessed by qPCR in addition to other PD therapeutic targets. Two patients from each group received multi-shell diffusion MRI scans to assess for free water (FW) changes in the dorsomedial nucleus of the thalamus and nucleus basalis of Meynert, which reflect cognitive decline in PD, and the posterior substantia nigra, which reflects motor decline in PD. Results: Two of the six patients receiving medium-dose lithium therapy withdrew due to side effects. Medium-dose lithium therapy was associated with the greatest numerical increases in PBMC Nurr1 and SOD1 expression (679% and 127%, respectively). Also, medium-dose lithium therapy was the only dosage associated with mean numerical decreases in brain FW in all three regions of interest, which is the opposite of the known longitudinal FW changes in PD. Conclusion: Medium-dose lithium aspartate therapy was associated with engagement of blood-based therapeutic targets and improvements in MRI disease-progression biomarkers but was poorly tolerated in 33% of patients. Further PD clinical research is merited examining lithium's tolerability, effects on biomarkers and potential disease-modifying effects.

Effect of gabapentin on hyperemesis gravidarum: a double-blind, randomized controlled trial.

BACKGROUND: Hyperemesis gravidarum is a disabling disease of nausea, vomiting, and undernutrition in early pregnancy for which there are no effective outpatient therapies. Poor weight gain in hyperemesis gravidarum is associated with several adverse fetal outcomes including preterm delivery, low birthweight, small for gestational age, low 5-minute Apgar scores, and neurodevelopmental delay. Gabapentin is most commonly used clinically for treating neuropathic pain but also substantially reduces chemotherapy-induced and postoperative nausea and vomiting. Pregnancy registry data have shown maternal first-trimester gabapentin monotherapy to be associated with a 1.2% rate of major congenital malformations among 659 infants, which compares favorably with the 1.6% to 2.2% major congenital malformation rate in the general population. Open-label gabapentin treatment in hyperemesis gravidarum was associated with reduced nausea and vomiting and improved oral nutrition. OBJECTIVE: This study aimed to determine whether gabapentin is more effective than standard-of-care therapy for treating hyperemesis gravidarum. STUDY DESIGN: A double-blind, randomized, multicenter trial was conducted among patients with medically refractory hyperemesis gravidarum requiring intravenous hydration. Patients were randomized (1:1) to either oral gabapentin (1800-2400 mg/d) or an active comparator of either oral ondansetron (24-32 mg/d) or oral metoclopramide (45-60 mg/d) for 7 days. Differences in Motherisk-pregnancy-unique quantification of nausea and emesis total scores between treatment groups averaged over days 5 to 7, using intention-to-treat principle employing a linear mixed-effects model adjusted for baseline Motherisk-pregnancy-unique quantification of nausea and emesis scores, which served as the primary endpoint. Secondary outcomes included Motherisk-pregnancy-unique quantification of nausea and emesis nausea and vomit and retch subscores, oral nutrition, global satisfaction of treatment, relief, desire to continue therapy, Nausea and Vomiting of Pregnancy Quality of Life, and Hyperemesis Gravidarum Pregnancy Termination Consideration. Adjustments for multiple comparisons were made employing the false discovery rate. RESULTS: A total of 31 patients with hyperemesis gravidarum were enrolled from October 2014 to May 2019. Among the 21 patients providing primary outcome data (12 assigned to gabapentin and 9 to the active comparator arm), 18 were enrolled as outpatients and all 21 were outpatients from days 5 to 7. The study groups' baseline characteristics were well matched. Gabapentin treatment provided a 52% greater reduction in days 5 to 7 baseline adjusted Motherisk-pregnancy-unique quantification of nausea and emesis total scores than treatment with active comparator (95% confidence interval, 16-88; P=.01). Most secondary outcomes also favored gabapentin over active comparator treatment including 46% and 49% decreases in baseline adjusted Motherisk-pregnancy-unique quantification of nausea and emesis nausea (95% confidence interval, 19-72; P=.005) and vomit and retch subscores (95% confidence interval, 21-77; P=.005), respectively; a 96% increase in baseline adjusted oral nutrition scores (95% confidence interval, 27-165; P=.01); and a 254% difference in global satisfaction of treatment (95% confidence interval, 48-459; P=.03). Relief (P=.06) and desire to continue therapy (P=.06) both showed trends favoring gabapentin treatment but Nausea and Vomiting of Pregnancy Quality of Life (P=.68) and Hyperemesis Gravidarum Pregnancy Termination Consideration (P=.58) did not. Adverse events were roughly equivalent between the groups. There were no serious adverse events. CONCLUSION: In this small trial, gabapentin was more effective than standard-of-care therapy for reducing nausea and vomiting and increasing oral nutrition and global satisfaction in outpatients with hyperemesis gravidarum. These data build on previous findings in other patient populations supporting gabapentin as a novel antinausea and antiemetic therapy and support further research on gabapentin for this challenging complication of pregnancy.

Long-standing multiple sclerosis neurodegeneration: volumetric magnetic resonance imaging comparison to Parkinson's disease, mild cognitive impairment, Alzheimer's disease, and elderly healthy controls.

Multiple sclerosis (MS) exhibits neurodegeneration driven disability progression. We compared the extent of neurodegeneration among 112 long-standing MS patients, 37 Parkinson's disease (PD) patients, 34 amnestic mild cognitive impairment (aMCI) patients, 37 Alzheimer's disease (AD) patients, and 184 healthy controls. 3T MRI volumes of whole brain (WBV), white matter (WMV), gray matter (GMV), cortical (CV), deep gray matter (DGM), and nuclei-specific volumes of thalamus, caudate, putamen, globus pallidus, and hippocampus were derived with SIENAX and FIRST software. Аge and sex-adjusted analysis of covariance was used. WBV was not significantly different between diseases. MS had significantly lower WMV compared to other disease groups (p < 0.021). Only AD had smaller GMV and CV when compared to MS (both p < 0.001). MS had smaller DGM volume than PD and aMCI (p < 0.001 and p = 0.026, respectively) and lower thalamic volume when compared to all other neurodegenerative diseases (p < 0.008). Long-standing MS exhibits comparable global atrophy with lower WMV and thalamic volume when compared to other classical neurodegenerative diseases.

High lithium levels in tobacco may account for reduced incidences of both Parkinson's disease and melanoma in smokers through enhanced ß-catenin-mediated activity.

Parkinson's disease (PD) patients have higher rates of melanoma and vice versa, observations suggesting that the two conditions may share common pathogenic pathways. ß-Catenin is a transcriptional cofactor that, when concentrated in the nucleus, upregulates the expression of canonical Wnt target genes, such as Nurr1, many of which are important for neuronal survival. ß-Catenin-mediated activity is decreased in sporadic PD as well as in leucine-rich repeat kinase 2 (LRRK2) and ß-glucosidase (GBA) mutation cellular models of PD, which is the most common genetic cause of and risk for PD, respectively. In addition, ß-catenin expression is significantly decreased in more aggressive and metastatic melanoma. Multiple observational studies have shown smokers to have significantly lower rates of PD as well as melanoma implying that tobacco may contain one or more elements that protect against both conditions. In support, smoker's brains have significantly reduced levels of α-synuclein, a pathological intracellular protein found in PD brain and melanoma cells. Tobacco contains very high lithium levels compared to other plants. Lithium has a broad array of neuroprotective actions, including enhancing autophagy and reducing intracellular α-synuclein levels, and is effective in both neurotoxin and transgenic preclinical PD models. One of lithium's neuroprotective actions is enhancement of ß-catenin-mediated activity leading to increased Nurr1 expression through its ability to inhibit glycogen synthase kinase-3 ß (GSK-3ß). Lithium also has anti-proliferative effects on melanoma cells and the clinical use of lithium is associated with a reduced incidence of melanoma as well as reduced melanoma-associated mortality. This is the first known report hypothesizing that inhaled lithium from smoking may account for the associated reduced rates of both PD and melanoma and that this protection may be mediated, in part, through lithium-induced GSK-3ß inhibition and consequent enhanced ß-catenin-mediated activity. This hypothesis could be directly tested in clinical trials assessing lithium therapy's ability to affect ß-catenin-mediated activity and slow disease progression in patients with PD or melanoma.

Targeting kinases in Parkinson's disease: A mechanism shared by LRRK2, neurotrophins, exenatide, urate, nilotinib and lithium.

Several kinases have been implicated in the pathogenesis of Parkinson's disease (PD), most notably leucine-rich repeat kinase 2 (LRRK2), as LRRK2 mutations are the most common genetic cause of a late-onset parkinsonism that is clinically indistinguishable from sporadic PD. More recently, several other kinases have emerged as promising disease-modifying targets in PD based on both preclinical studies and clinical reports on exenatide, the urate precursor inosine, nilotinib and lithium use in PD patients. These kinases include protein kinase B (Akt), glycogen synthase kinases-3ß and -3α (GSK-3ß and GSK-3α), c-Abelson kinase (c-Abl) and cyclin-dependent kinase 5 (cdk5). Activities of each of these kinases are involved either directly or indirectly in phosphorylating tau or increasing α-synuclein levels, intracellular proteins whose toxic oligomeric forms are strongly implicated in the pathogenesis of PD. GSK-3ß, GSK-3α and cdk5 are the principle kinases involved in phosphorylating tau at sites critical for the formation of tau oligomers. Exenatide analogues, urate, nilotinib and lithium have been shown to affect one or more of the above kinases, actions that can decrease the formation and increase the clearance of intraneuronal phosphorylated tau and α-synuclein. Here we review the current preclinical and clinical evidence supporting kinase-targeting agents as potential disease-modifying therapies for PD patients enriched with these therapeutic targets and incorporate LRRK2 physiology into this novel model.

Effects of L-isoleucine and L-valine on hot flushes and serum homocysteine: a randomized controlled trial.

OBJECTIVE: To investigate whether L-isoleucine was effective in the treatment of hot flushes and whether L-isoleucine, L-valine, or the combination of both amino acids reduced fasting serum homocysteine. METHODS: After a 1-week baseline period, 100 postmenopausal women experiencing at least five moderate-severe hot flushes per day were randomized with equal probability to one of four groups (phase 1/phase 2): placebo/L-valine, placebo/L-valine and L-isoleucine, L-isoleucine/L-valine, and L-isoleucine/L-valine and L-isoleucine. Phase 1 was 12 weeks long, and phase 2 was 10 weeks long. Patients took five capsules by mouth, twice a day throughout the study, with each capsule containing 500 mg of compound. Data were obtained from daily hot flush diaries, fasting blood work, and several questionnaires. The primary outcome variable was the percent change in hot flush composite score from baseline to week 12. RESULTS: In phase 1 of the study, there were no significant differences between the L-isoleucine and placebo groups for any of the outcome measures. At week 12, there was a mean 13.9% decrease in hot flush composite score compared with baseline in the L-isoleucine group and a mean 25% decrease in the placebo group (P=.28). In phase 2 of the study, there was no significant change in fasting serum homocysteine levels associated with any of the amino acid therapies. CONCLUSION: L-isoleucine therapy appears to be ineffective in the treatment of hot flushes in postmenopausal women. L-isoleucine and L-valine, either alone or in combination, appear to have no effect on fasting serum homocysteine levels. CLINCIAL TRIAL REGISTRATION: ClinicalTrials.gov, (www.clinicaltrials.gov), NCT00081952. LEVEL OF EVIDENCE: I.

Gabapentin, estrogen, and placebo for treating hot flushes: a randomized controlled trial.

OBJECTIVE: To compare the efficacy of gabapentin, estrogen, and placebo in the treatment of hot flushes. METHODS: We performed a randomized, double-blind, placebo-controlled trial of 60 postmenopausal women to assess the efficacy of estrogen and gabapentin in the treatment of moderate-to-severe hot flushes. Participants were randomly assigned to receive either 0.625 mg/d of conjugated estrogens (n = 20), placebo (n = 20), or gabapentin titrated to 2,400 mg/d (n = 20) for 12 weeks. Participants recorded frequency and severity of baseline hot flushes on a hot flush diary for 2 weeks before randomization and for 12 weeks after randomization. The primary outcome measure was the weekly hot flush composite score, which takes into account both severity and frequency of hot flushes. Secondary outcome measures were differences in pre- and posttreatment scores pertaining to depression (Zung Depression Scale) and other climacteric symptoms (Greene Climacteric Scale). RESULTS: Intention-to-treat analysis showed that the reduction in the hot flush composite score for both estrogen (72%, P = .016) and gabapentin (71%, P = .004) was greater than the reduction associated with placebo (54%) at the conclusion of the 12th week. The extent of reduction in hot flush composite score, however, was not significantly different between estrogen and gabapentin (P = .63). No differences were seen between groups in the Zung Depression Scale, or in any of the Greene Climacteric subscales except for the Somatic Symptom cluster, which was significantly greater in the gabapentin arm than in the placebo arm. Despite a lack of group differences in adverse events, the Headache, Dizziness, and Disorientation cluster appeared with greater frequency in the gabapentin group. Estimation of the number needed to harm in this cluster suggests that these symptoms may occur with every fourth patient treated with gabapentin. CONCLUSION: Despite the small scale of this study, gabapentin appears to be as effective as estrogen in the treatment of postmenopausal hot flushes. CLINICAL TRIAL REGISTRATION: Clinicaltrials.gov, NCT 00276081. LEVEL OF EVIDENCE: I.

Responsiveness of life-threatening refractory emesis to gabapentin-scopolamine therapy following posterior fossa surgery. Case report.

Craniotomy-associated chronic emesis can be refractory to currently approved antiemetic therapy. The authors describe a man who suffered 4 weeks of severe refractory emesis, failure to thrive, and a 40-lb weight loss after he underwent resection of a posterior fossa cholesteatoma. The patient experienced complete resolution of emesis and anorexia in response to combined gabapentin-scopolamine therapy. This case provides anecdotal evidence for the use of gabapentin-scopolamine therapy in patients with chronic, refractory nausea and emesis, particularly following posterior fossa surgery, during which medullary nausea and emesis centers may be affected.

Treatment of chronic insomnia disorder in menopause: evaluation of literature.

OBJECTIVE: Insomnia both as a symptom and as part of chronic insomnia disorder is quite common in menopause. Comorbid conditions, such as restless legs syndrome and obstructive sleep apnea, occur with high prevalence among perimenopausal women with insomnia. Insomnia in this population group is associated with adverse health outcomes, and there are no clear standards on how to treat it. METHODS: Based on extensive literature search, 76 articles were identified. Two authors independently graded evidence according to the Oxford Centre for Evidence-Based Medicine Levels of Evidence. RESULTS: Evaluation and treatment of other comorbid sleep disorders are recommended, as is cognitive-behavioral therapy for insomnia. Hormone therapy, eszopiclone, escitalopram, gabapentin, isoflavones, valerian, exercise, and hypnosis are suggested. Zolpidem, quiteiapine XL, citalopram, mirtazapine followed by long-acting melatonin, ramelteon, Pycnogenol, Phyto-Female Complex, yoga, and massage may be considered. Kampo formulas are not recommended. Acupuncture may not be suggested, and cognitive-behavioral therapy that is not tailored for insomnia probably should not be considered. CONCLUSIONS: Although a variety of interventions are shown to be helpful in improving sleep in menopause, there is a need for well-designed head-to-head trials with uniform outcome measures.

Gabapentin's effects on hot flashes in postmenopausal women: a randomized controlled trial.

OBJECTIVE: To evaluate whether treatment with the anticonvulsant gabapentin may be effective in reducing hot flash frequency and severity. METHODS: A randomized, double-blind, placebo-controlled trial was conducted in 59 postmenopausal women with seven or more hot flashes per day examining the effects of gabapentin 900 mg per day on hot flash frequency after 12 weeks of treatment. Subsequently, study patients were enrolled in a 5-week, open-label treatment phase, during which patients could increase the dose of gabapentin to 2,700 mg per day, if needed. RESULTS: After 12 weeks of double-blind treatment, intention-to-treat analysis showed that gabapentin 900 mg per day was associated with a 45% reduction in hot flash frequency and a 54% reduction in hot flash composite score (frequency and severity combined into one score) from baseline, compared with 29% (P =.02) and 31% (P =.01) reductions, respectively, for placebo. Four patients (13%) in the gabapentin group and one (3%) in the placebo group withdrew from the double-blind study because of adverse events. Fifteen patients (50.0%) in the gabapentin group reported at least one adverse event, compared with eight patients (27.6%) in the placebo group. Higher, open-label gabapentin dosing was associated with 54% and 67% reductions in hot flash frequency and composite score from baseline, respectively. CONCLUSION: Gabapentin is effective in reducing hot flash frequency and severity in postmenopausal women.

Hot flashes refractory to HRT and SSRI therapy but responsive to gabapentin therapy.

There is a need for alternative therapies for hot flashes, as hormone replacement therapy (HRT) is associated with increased rates of breast cancer and heart disease, and some women fail to respond to HRT. A 32-year-old woman with surgically-induced menopause experienced 20-30 severe hot flashes per day and failed to respond to various formulations of HRT and selective serotonin reuptake inhibitor (SSRI) therapy for 17 years. She markedly responded to gabapentin therapy. Gabapentin, SSRIs, and estrogen may act at different cellular targets in the treatment of hot flashes.

Potential maternal symptomatic benefit of gabapentin and review of its safety in pregnancy.

Restless legs syndrome (RLS) and nausea and vomiting of pregnancy (NVP) are both common maternal conditions affecting quality of life. Gabapentin is currently FDA-approved for treating RLS and preliminary results have shown it may be effective for treating the most severe form of NVP, hyperemesis gravidarum (HG). Because NVP and HG symptoms peak early in pregnancy, the potential teratogenicity of gabapentin needs to be considered. We reviewed published pregnancy registries and cohorts for pregnancy outcomes associated with maternal gabapentin use. Gabapentin exposures from 5 pregnancy registries, 1 HG pilot study and 2 additional cases were reviewed. Among 294 first trimester gabapentin-monotherapy exposures, there were 5 major congenital malformations (MCMs) reported (1.7%), which favorably compares to the MCM rate in the general population (1.6-2.2%). Two of the registries reported maternal gabapentin use among 261 singleton pregnancies to be associated with roughly equivalent rates of premature birth, birth weight after correction for gestational age at delivery and maternal hypertension/eclampsia as those that have been reported in the general population. These data support the safety of gabapentin use in pregnancy; however, the number of exposures to date is still small. If future pregnancy registry data confirm this positive safety profile, gabapentin therapy would likely be a safe and effective treatment for RLS during pregnancy. Controlled, clinical trials are needed to assess gabapentin's effectiveness for HG.

Stellate ganglion block for treating hot flashes: a viable treatment option or sham procedure?

Stellate ganglion block (SGB) has been used for over 70 years to treat various cervical pain syndromes. Over the past 8 years, 4 different groups have reported on SGB's effects on hot flashes from unblinded, open-label trials. Review of these studies has shown markedly disparate results in terms of the magnitude of hot flash reduction from Baseline with one trial showing a 90% reduction in hot flashes and 3 other trials showing 28-44% reductions in hot flashes. The inconsistencies in these results in addition to the known potentially large (>50%) placebo effects that can occur in randomized controlled hot flash clinical trials make it difficult to render any conclusions regarding the efficacy of SGB for hot flashes at this time. A randomized controlled trial, including a sham saline treatment arm, needs to be performed to properly assess SGB's effects on hot flashes, Methodological challenges with such a study design are addressed and several suggestions are proposed to manage these challenges.

Effective and clinically meaningful non-hormonal hot flash therapies.

Although many non-hormonal compounds have shown statistically significant benefit over placebo in hot flash randomized controlled trials (RCTs), these studies have varied considerably in basic methodology making it challenging to deduce which compounds have the greatest potential to provide clinically meaningful benefit. This review used evidence-based methodology closely mirroring the FDA and EMEA guidelines as a template to identify "well-designed" RCTs from which effective and clinically meaningful non-hormonal hot flash therapies could be identified. In addition, pertinent safety information was reviewed. Out of 3548 MEDLINE citations and abstracts, 51 well-designed hot flash RCTs were identified. From these trials, gabapentin, oxybutynin ER, desvenlafaxine, soy-derived isoflavones and black cohosh each showed a clinically meaningful treatment effect in at least 1 RCT. Among these 5 compounds, only gabapentin demonstrated consistent and statistically significant benefit over placebo in all of its well-designed RCTs. Desvenlafaxine, soy-derived isoflavones, and black cohosh demonstrated statistically significant benefit over placebo in 75%, 21%, and 17% of the well-designed RCTs for each compound, respectively. There was only 1 well-designed RCT using oxybutynin ER, which showed it to have a robust and clinically meaningful benefit. In terms of safety, there have been cardiovascular risks associated with desvenlafaxine use in postmenopausal women with hot flashes. The use of anticonvulsants, in general, has been associated with an absolute 0.21% increase in suicidal thoughts and behavior. Further research is needed with several of these nonhormonal compounds to replicate these findings and to also directly compare their efficacy and tolerability with those of hormone replacement therapy.