Hussain, Nasir

Peripheral nerve stimulation (PNS) has been utilized for over 50 years with accumulating evidence of efficacy in a variety of chronic pain conditions. The level and strength of evidence supporting the use of PNS for peripheral neuropathic pain remains unclear. The purpose of this review is to synthesize data from prospective studies on the efficacy of PNS for neuropathic pain as it pertains to pain intensity, neurological deficits/neuropathy (e.g., weakness, sensory deficits, gait/balance), and other secondary outcomes (quality of life, satisfaction, emotional functioning, and adverse events). In compliance with the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines, this review identified articles from MEDLINE(R), EMBASE, Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, and Scopus. Overall, per the Grading of Recommendations Assessment, Development and Evaluation (GRADE) criteria, pooled results demonstrate very low quality or low quality of evidence supporting modest to substantial improvement in pain and neurological function after PNS implantation for treatment of peripheral neuropathic pain. PNS for phantom limb pain was the only indication that had moderate level evidence. Future prospective and well-powered studies are warranted to assess the efficacy of PNS for peripheral neuropathic pain.

Background: CHA2DS2-VASc score has been shown to predict occurrences of incident stroke in patients with history of atrial fibrillation (A-Fib)/ Flutter. However, data on whether if CHA2DS2-VASc score would predict incidence of stroke in patients without A-Fib/ Flutter is less clear. Methods: From 1993 through 2010, all patients undergoing a clinically indicated treadmill exercise test (TMET) at the Mayo Clinic, Rochester, MN were identified (N= 76,857). From this, Olmsted and neighboring counties residents were selected (N=14,095). From this, patients with age <18 years; prior history of valvular heart disease or A-Fib/ Flutter were excluded. Patient undergoing only Bruce or accelerated Naughton protocols on TMET were considered. Patients were stratified into 4 groups at baseline based on CHA2DS2-VASc score as determined at the time of TMET; group-0 score=0; group-I=1; group-2=2; group-3≥3. Patients were prospectively followed from the date of TMET until end of January 2016 for occurrence of incident stroke (ischemic and hemorrhagic). Stroke diagnosis was ascertained through retrospective chart review. Traumatic intracranial bleed was not considered. Proportional hazard regression modeling was done to assess relationship of CHA2DS2-VASc score with the stroke outcome while adjusting for METs achieved, sex, obesity, smoking status, and other relevant risk factors. Results: Final study population comprised of 12,624 patients with female comprising 37% of the cohort. Mean age in our study group was 52.2 ± 12.8 years. During an overall median follow-up of 14 (8 to 17) years, 1,255 (9.9%) patients developed incident stroke. While using CHA2DS2-VASc group-3 as referent, patients in CHA2DS2-VASc group-0 [0.18(0.14-0.23, p<.001)], group-1[0.33 (0.28-0.39, p<.001)], and group-2 [0.50 (0.43-0.58, p<.001)] were at significantly lower risk of developing stroke. Each increase of one point on the CHA2DS2-VASc scale was associated with a 51% [1.51(1.45-1.58, p<.001)] increase in incidence of stroke. Conclusion: CHA2DS2-VASc score predicts incidence of stroke in patients without history of A-Fib/ Flutter.

Abstract BACKGROUND A decrease in diastolic blood pressure (DBP) with exercise is considered normal, but the significance of an increase in DBP has not been validated. Our aim was to determine the relationship of DBP increasing on a stress test regarding comorbidities and mortality. METHODS Our database was reviewed from 1993 to 2010 using the first stress test of a patient. Non-Minnesota residence, baseline cardiovascular (CV) disease, rest DBP &lt;60 or &gt;100 mm Hg, and age &lt;30 or ≥80 were exclusion criteria. DBP response was classified: normal if peak DBP–rest DBP &lt; 0, borderline 0–9, and abnormal ≥10 mm Hg. Mortality was determined from Mayo Clinic records and Minnesota Death Index. Logistic regression was used to determine the relationship of DBP response to the presence of comorbidities. Cox regression was used to determine total and CV mortality risk by DBP response. All analyses were adjusted for age, sex, and resting DBP. RESULTS Twenty thousand seven hundred sixty patients were included (51 ± 11 years, female n = 7,314). Rest/peak averaged DBP 82 ± 8/69 ± 15 mm Hg in normal vs. 79 ± 9/82 ± 9 mm Hg in borderline vs. 76 ± 9/92 ± 11 mm Hg in abnormal DBP response. There were 1,582 deaths (8%) with 557 (3%) CV deaths over 12 ± 5 years of follow-up. In patients with borderline and abnormal DBP response, odds ratios for obesity, hypertension, diabetes, and current smoking were significant, while hazard ratios for total and CV death were not significant compared with patients with normal DBP response. CONCLUSIONS DBP response to exercise is significantly associated with important comorbidities at the time of the stress test but does not add to the prognostic yield of stress test.

Background Heart rate ( HR ) recovery has been investigated in specific patient cohorts, but there is less information about the role of HR recovery in general populations. We investigated whether HR recovery has long‐term prognostic significance in primary prevention. Methods and Results Exercise tests performed between 1993 and 2010 on patients aged 30 to 79 years without cardiovascular disease were included. Mortality was determined from Mayo Clinic records and Minnesota Death Index. Total, cardiovascular , and non‐cardiovascular mortality was reported according to HR recovery <13 bpm using Cox regression. 19 551 patients were included, 6756 women (35%), age 51±10 years. There were 1271 deaths over follow‐up of 12±5 years. HR recovery declined after age 60, and was also lower according to diabetes mellitus, hypertension, obesity, current smoking, and poor cardiorespiratory fitness but not sex or β‐blockers. Adjusting for these factors, abnormal HR recovery was a significant predictor of total (hazard ratio [95% confidence interval]=1.56 [1.384–1.77]), cardiovascular (1.95 [1.57–2.42]), and non‐cardiovascular death (1.41 [1.22–1.64]). Hazard ratios for cardiovascular death according to abnormal HR recovery were significant in all age groups (30–59, 60–69, 70–79), in both sexes, in patients with and without hypertension, obesity, and diabetes mellitus, but not in patients taking β‐blockers, current smokers, and patients with normal cardiorespiratory fitness. Conclusions HR recovery is a powerful prognostic factor predicting total, cardiovascular, and non‐cardiovascular death in a primary prevention cohort. It performs consistently well according to sex, age, obesity, hypertension, and diabetes mellitus but shows diminished utility in patients taking β‐blockers, current smokers, and patients with normal cardiorespiratory fitness.