Recent human and animal studies provide growing evidence that vagal nerve stimulation (VNS) can deliver strong analgesic effects in addition to providing therapeutic efficacy in the treatment of refractory epilepsy and depression. Analgesia is potentially mediated by vagal afferents that inhibit spinal nociceptive reflexes and transmission and have strong anti-inflammatory properties. The purpose of this review is to provide pain practitioners with an overview of VNS technology and limitations. It specifically focuses on clinical indications of VNS for various chronic pain syndromes, including fibromyalgia, pelvic pain, and headaches. We also present potential mechanisms for VNS modulation of chronic pain by reviewing both animal and human studies.

We found a high no-show rate, which was associated with predictable and unpredictable (eg, snow) factors. Steps to reduce the no-show rate are discussed. To maximize access to care, operation managers should consider a regression model that accounts for patient-level risk of predictable no-shows. Knowing the patient level, no-show rate can potentially help to optimize the schedule programming by staggering low- versus high-probability no-shows.

Subjects at risk for atherosclerosis may have dysfunctional high-density lipoprotein (HDL) despite normal cholesterol content in plasma. We considered whether efflux of excess cellular cholesterol to HDL from obese subjects is associated with impaired arterial endothelial function, a biomarker of cardiovascular risk. Fifty-four overweight (body mass index [BMI] 25 – 29.9 kg/m2) or obese women (BMI ≥ 30 kg/m2), age 46 ± 11 years, were enrolled in a worksite wellness program. HDL cholesterol averaged 57 ± 17 mg/dL and was inversely associated with BMI (r= −0.419, P= 0.002). Endothelial function was assessed by brachial artery flow-mediated dilation (FMD). Cholesterol efflux from 3H-cholesterol-labeled BHK cells transfected with the ATP-binding cassette transporter 1 (ABCA1) showed 8.2 to 22.5% cholesterol efflux over 18 hours when incubated with 1% serum and was positively correlated with FMD (P <0.05), especially in the 34 subjects with BMI ≥ 30 kg/m2 (r= 0.482, P= 0.004). This relation was independent of age, HDL or low-density lipoprotein cholesterol (LDL) concentrations in plasma, blood pressure or insulin resistance by stepwise multiple regression analysis (β= 0.31, R2= 0.21, P= 0.007). Nitration of apoA-I tyrosine residues (by sandwich ELISA) was significantly higher in women with BMI ≥ 30 kg/m2 and the lowest cholesterol efflux than in women with BMI 25 – 29.9 kg/m2 and the highest cholesterol efflux (P= 0.01). We conclude that decreased cholesterol efflux via the ABCA1 transporter is associated with increased nitration of apoA-I in HDL and is an independent predictor of impaired endothelial function in women with BMI ≥ 30 kg/m2. This finding suggests that functional measures of HDL may be better markers for cardiovascular risk than HDL cholesterol levels in this population.

A sedentary work force may be at increased risk of future cardiovascular disease. Exercise at the worksite has been advocated, but effects on endothelium as a biomarker of risk and relation to weight loss, lipid changes or circulating endothelial progenitor cells (EPCs) have not been reported. Seventytwo office and laboratory (26 with body-mass index [BMI] > 30 kg/m 2 ) employees (58 women; average age 45 years; range: 22-62 years) completed 3 months of participation in the National Heart, Lung, and Blood Institute's "Keep the Beat" program, with determination of vital signs, laboratory data and peak oxygen consumption (VO 2 ) during treadmill exercise. Brachial artery endothelium was tested by flow-mediated dilation (FMD), which at baseline was inversely associated with Framingham risk score (r=-0.3689, P<0.0001). EPCs were quantified by colony assay. With exercise averaging 98±47 (mean±SD) minutes each work week, there was improvement in FMD (from 7.8 ±3.4 to 8.5±3.0%, P=0.0096) and peak VO 2 (+1.2±3.1 mL O 2 /kg/min; P=0.0028), with reduction in diastolic blood pressure (-2±8 mmHg; P=0.0478), total cholesterol (-8±25 mg/dL, P=0.0131), lowdensity lipoprotein (LDL) cholesterol (-7±19 mg/dL, P=0.0044), but with marginal reduction in weight (-0.5±2.1 kg, P=0.0565). By multiple regression modeling, lower baseline FMD, greater age, reductions in total and LDL cholesterol and diastolic blood pressure, and increases in EPC colonies and peak VO 2 were jointly statistically significant predictors of change in FMD and accounted for 47% of the variability in FMD improvement with program participation. Results were similar when modeling was performed for women only. By contrast, neither adiposity at baseline nor change in weight were predictors of improved endothelial function. In conclusion, daily exercise achievable in the worksite by employees with sedentary occupations improves endothelial function-even with absence of weight loss--which may decrease cardiovascular risk, if sustained. Keywords endothelium; nitric oxide; obesity; lipoproteins; exercise Exercise has been associated with multiple health benefits, including favorable effects on lipids, blood pressure, insulin sensitivity and endothelial function 1-5 , yet almost two-thirds of