Background
Vertebral subluxation (VS) is a clinical entity defined as a misalignment of the spine affecting biomechanical and neurological function. The identification and correction of VS is the primary focus of the chiropractic profession. The purpose of this study is to estimate VS prevalence using a sample of individuals presenting for chiropractic care and explore the preventative public health implications of VS through the promotion of overall health and function.
Methodology
A brief review of the literature was conducted to support an operational definition for VS that incorporated neurologic and kinesiologic exam components. A retrospective, quantitative analysis of a multi-clinic dataset was then performed using this operational definition. Descriptive statistics on patient demographic data included age, gender, and past health history characteristics. In addition to calculating estimates of the overall prevalence of VS, age- and gender-stratified estimates in the different clinics were calculated to allow for potential variations.
Results
A total of 1,851 patient records from seven chiropractic clinics in four states were obtained. The mean age of patients was 43.48 (SD = 16.8, range = 18-91 years). There were more females (n = 927, 64.6%) than males who presented for chiropractic care. Patients reported various reasons for seeking chiropractic care, including, spinal or extremity pain, numbness, or tingling; headaches; ear, nose, and throat-related issues; or visceral issues. Mental health concerns, neurocognitive issues, and concerns about general health were also noted as reasons for care. The overall prevalence of VS was 78.55% (95% CI = 76.68-80.42). Female and male prevalence of VS was 77.17% and 80.15%, respectively; notably, all per-clinic, age, or gender-stratified prevalences were ≥50%.
Conclusions
To date, this is the first study of its magnitude and application of an operational definition to estimate the prevalence of VS. Albeit nonrandom, the sample had a broad geographic distribution. The results of this study suggest a high rate of prevalence of VS in a sample of individuals who sought chiropractic care. Concerns about general health and wellness were represented in the sample and suggest chiropractic may serve a primary prevention function in the absence of disease or injury. Further investigation into the epidemiology of VS and its role in health promotion and prevention is recommended.
Objective
The impact of previous aortic root replacement (True-Redo) versus any previous operation (Any-Redo) on outcomes after reoperative aortic root replacement (redo-ROOT) is largely unknown. In this first multi-institutional study, the clinical impact True-Redo versus Any-Redo in the setting of redo-ROOT was reviewed.
Methods
From 2004 to 2021, 822 patients underwent redo-ROOT at 2 major academic centers: 638 Any-Redo and 184 True-Redo. Matching based on preoperative demographics and concomitant operations resulted in 174 matched pairs. An independent risk factor analysis was performed to determine risk factors for early and late mortality.
Results
Patients in the True-Redo group were younger, at 49.9 ± 15.1 versus 55.3 ± 14.7 years, P < .001. Concomitant operations were largely similar between the 2 groups, P > .05. Median cardiopulmonary bypass time (P < .001) and aortic crossclamp time (P = .03) were longer for True-Redo group. In-hospital mortality was 13% (109) and was without significant difference between groups, P = .41. Ten-year survival was 78% versus 76% for True-Redo versus Any-Redo groups respectively, P = .7. Landmark survival analysis at 4 years' postoperatively on the matched groups found that patients in the True-Redo group had improved survival outcomes (P = .046). Risk factors of in-hospital mortality consisted of older age (P < .0001), lower ejection fraction (P = .02), and male patient (P = .0003).
Conclusions
Clinical outcomes following redo-ROOT are excellent. Performance of a True-Redo-ROOT does not result in worse in-hospital morbidity or mortality and has improved survival benefit at midterm follow-up when compared with patients in the Any-Redo group. The decision to perform a redo-ROOT must be taken seriously and must be individualized in a patient-specific manner for optimal outcomes.
Background
The accuracy of computer-aided diagnosis (CAD) software is best evaluated by comparison to a gold standard which represents the true status of disease. In many settings, however, knowledge of the true status of disease is not possible and accuracy is evaluated against the interpretations of an expert panel. Common statistical approaches to evaluate accuracy include receiver operating characteristic (ROC) and kappa analysis but both of these methods have significant limitations and cannot answer the question of equivalence: Is the CAD performance equivalent to that of an expert? The goal of this study is to show the strength of log-linear analysis over standard ROC and kappa statistics in evaluating the accuracy of computer-aided diagnosis of renal obstruction compared to the diagnosis provided by expert readers.
Methods
Log-linear modeling was utilized to analyze a previously published database that used ROC and kappa statistics to compare diuresis renography scan interpretations (non-obstructed, equivocal, or obstructed) generated by a renal expert system (RENEX) in 185 kidneys (95 patients) with the independent and consensus scan interpretations of three experts who were blinded to clinical information and prospectively and independently graded each kidney as obstructed, equivocal, or non-obstructed.
Results
Log-linear modeling showed that RENEX and the expert consensus had beyond-chance agreement in both non-obstructed and obstructed readings (both p < 0.0001). Moreover, pairwise agreement between experts and pairwise agreement between each expert and RENEX were not significantly different (p = 0.41, 0.95, 0.81 for the non-obstructed, equivocal, and obstructed categories, respectively). Similarly, the three-way agreement of the three experts and three-way agreement of two experts and RENEX was not significantly different for non-obstructed (p = 0.79) and obstructed (p = 0.49) categories.
Conclusion
Log-linear modeling showed that RENEX was equivalent to any expert in rating kidneys, particularly in the obstructed and non-obstructed categories. This conclusion, which could not be derived from the original ROC and kappa analysis, emphasizes and illustrates the role and importance of log-linear modeling in the absence of a gold standard. The log-linear analysis also provides additional evidence that RENEX has the potential to assist in the interpretation of diuresis renography studies.
Background
Tarlov cyst disease is a collection of cerebrospinal fluid between the endoneurium and perineurium of spinal, usually sacral, nerve roots. These cysts can become symptomatic in 20% of patients, causing lower back pain, radiculopathy, bladder and bowel dysfunction necessitating medical or surgical intervention. Different surgical and non-surgical modalities have been described for the treatment of symptomatic Tarlov cysts. However, there has been no published study that examined types of surgical techniques side by side. Our study presents a preliminary experience in the surgical management of symptomatic Tarlov cysts using two surgical techniques: cyst fenestration and nerve root imbrication
Methods
Retrospective chart review and analysis was done for all patients who underwent surgical intervention for symptomatic Tarlov cyst(s) in the period 2007–2013. Operative reports, preoperative and postoperative clinic visit reports were reviewed. The surgical techniques of cyst fenestration and nerve root imbrication were each described in terms of intraoperative parameters, hospital course and outcome. Modified MacNab criteria were used for evaluation of the final clinical outcome.
Results
Thirty-six surgical patients were identified. Three had repeat surgery (total of 39 operations). The median age was 51 years (range, 26–84 years). Eighty-six percent were females. The presenting symptoms were low back pain (94%), sensory radiculopathy (69%), bladder and bowel dysfunction (61%), sexual dysfunction (17%) and motor dysfunction (8%). Cyst fenestration was performed in 12 patients (31%) and nerve root imbrication was done in 27 (69%). All patients in the fenestration group but only 67% in the imbrication group had fibrin glue injection into the cyst or around the reconstructed nerve root. The overall surgery-related complication rate was 28%. The complication rate was 5/12 (42%) in the fenestration group and 6/27 (22%) in the imbrication group. At the time of the last clinic visit, improved clinical outcome was noted in 9/11 (82%) and 20/25 (80%) in the fenestration and the imbrication group, respectively.
Conclusions
Cyst fenestration and nerve root imbrication are both surgical techniques to treat symptomatic Tarlov cyst(s), and both can result in clinical improvement.
Background: HIV-awareness programs tailored toward the needs of rural communities are needed. We sought to quantify change in HIV knowledge in three rural Nigerian villages following an integrated culturally adapted and technology assisted educational intervention.
Methods: A prospective 14-week cohort study was designed to compare short-term changes in HIV knowledge between seminar-based education program and a novel program, which capitalized on the rural culture of small-group oral learning and was delivered by portable digital-audio technology.
Results: Participants were mostly Moslem (99%), male (53.5%), with no formal education (55%). Baseline HIV knowledge was low (<80% correct answers for 9 of the 10 questions). Knowledge gain was higher (p < 0.0001 for 8 of 10 questions) in the integrated culturally adapted and technology-facilitated (n = 511) compared with the seminar-based (n = 474) program.
Conclusions: Baseline HIV-awareness was low. Culturally adapted, technology-assisted HIV education program is a feasible cost-effective method of raising HIV awareness among low-literacy rural communities.
Background:Traditional cardiovascular risk factors lead to endothelial injury and activation of leukocytes and platelets that initiate and propagate atherosclerosis. We proposed that clopidogrel therapy in patients with stable coronary artery disease imparts a pleiotropic effect that extends beyond antiplatelet aggregation to other atheroprotective processes.
Methods: Forty-one subjects were randomized in a double-blind, placebo-controlled, crossover study to receive either clopidogrel 75 mg daily or placebo for 6 weeks and then transitioned immediately to the other treatment for an additional 6 weeks. We assessed (1) endothelial function as flow-mediated dilation of the brachial artery, (2) arterial stiffness and central augmentation index using applanation tonometry, (3) vascular function as fingertip reactive hyperemia index, (4) inflammation by measuring plasma CD40 ligand and serum high-sensitivity c-reactive protein levels, (5) oxidative stress by measuring plasma aminothiols, and (6) circulating progenitor cells, at baseline and at the end of each 6-week treatment period.
Results: Clopidogrel therapy resulted in a significant reduction in soluble CD40 ligand (P = 0.03), a prothrombotic and proinflammatory molecule derived mainly from activated platelets. However, clopidogrel therapy had no effect on endothelial function, arterial stiffness, inflammatory and oxidative stress markers, or progenitor cells.
Conclusions: Our findings suggest a solitary antiplatelet effect of clopidogrel therapy in patients with stable coronary artery disease, with no effect on other subclinical markers of cardiovascular disease risk.
Background Progression of atherosclerosis is associated with a greater risk for adverse outcomes. Angiotensin II plays a key role in the pathogenesis and progression of atherosclerosis. We aimed to investigate the effects of angiotensin II type-1 receptor blockade with Valsartan on carotid wall atherosclerosis, with the hypothesis that Valsartan will reduce progression of atherosclerosis. Methods Subjects (n = 120) with carotid intima-media thickness >0.65 mm by ultrasound were randomized (2:1) in a double-blind manner to receive either Valsartan or placebo for 2 years. Bilateral T2-weighted black-blood carotid magnetic resonance imaging was performed at baseline, 12 and 24 months. Changes in the carotid bulb vessel wall area and wall thickness were primary endpoints. Secondary endpoints included changes in carotid plaque thickness, plasma levels of aminothiols, C-reactive protein, fibrinogen, and endothelium-dependent and -independent vascular function. Results Over 2 years, the carotid bulb vessel wall area decreased with Valsartan (-6.7, 95% CI [-11.6, -1.9] mm2) but not with placebo (3.4, 95% CI [-2.8, 9.6] mm2), P =.01 between groups. Similarly, mean wall thickness decreased with Valsartan (-0.18, 95% CI [-0.30, -0.06] mm), but not with placebo (0.08, 95% CI [-0.07, 0.23] mm), P =.009 between groups. Furthermore, plaque thickness decreased with Valsartan (-0.35, 95% CI [-0.63, -0.08] mm) but was unchanged with placebo (+0.28, 95% CI [-0.11, 0.69] mm), P =.01 between groups. These findings were unaffected by statin therapy or changes in blood pressure. Notably, there were significant improvements in the aminothiol cysteineglutathione disulfide, and trends to improvements in fibrinogen levels and endothelium-independent vascular function. Conclusions In subjects with carotid wall thickening, angiotensin II type-1 receptor blockade was associated with regression in carotid atherosclerosis. Whether these effects translate into improved outcomes in subjects with subclinical atherosclerosis warrants investigation.
BACKGROUND: Extremes of wall shear stress (WSS) have been associated with plaque progression and transformation, which has raised interest in the clinical assessment of WSS. We hypothesized that calculated coronary WSS is predicted only partially by luminal geometry and that WSS is related to plaque composition. METHODS AND RESULTS: Twenty-seven patients with coronary artery disease underwent virtual histology intravascular ultrasound and Doppler velocity measurement for computational fluid dynamics modeling for WSS calculation in each virtual histology intravascular ultrasound segment (N=3581 segments). We assessed the association of WSS with plaque burden and distribution and with plaque composition. WSS remained relatively constant across the lower 3 quartiles of plaque burden (P=0.08) but increased in the highest quartile of plaque burden (P<0.001). Segments distal to lesions or within bifurcations were more likely to have low WSS (P<0.001). However, the majority of segments distal to lesions (80%) and within bifurcations (89%) did not exhibit low WSS. After adjustment for plaque burden, there was a negative association between WSS and percent necrotic core and calcium. For every 10 dynes/cm(2) increase in WSS, percent necrotic core decreased by 17% (P=0.01), and percent dense calcium decreased by 17% (P<0.001). There was no significant association between WSS and percent of fibrous or fibrofatty plaque components (P=NS). CONCLUSIONS: IN PATIENTS WITH CORONARY ARTERY DISEASE: (1) Luminal geometry predicts calculated WSS only partially, which suggests that detailed computational techniques must be used to calculate WSS. (2) Low WSS is associated with plaque necrotic core and calcium, independent of plaque burden, which suggests a link between WSS and coronary plaque phenotype. (J Am Heart Assoc. 2012;1:e002543 doi: 10.1161/JAHA.112.002543.).
The purpose of the study was to compare diuresis renography scan interpretation generated by a renal expert system with the consensus interpretation of 3 expert readers.Methods
The expert system was evaluated in 95 randomly selected furosemide-augmented patient studies (185 kidneys) obtained for suspected obstruction; there were 55 males and 40 females with a mean age ± SD of 58.6 ± 16.5 y. Each subject had a baseline 99mTc-mercaptoacetyltriglycine (99mTc-MAG3) scan followed by furosemide administration and a separate 20-min acquisition. Quantitative parameters were automatically extracted from baseline and furosemide acquisitions and forwarded to the expert system for analysis. Three experts, unaware of clinical information, independently graded each kidney as obstructed/probably obstructed, equivocal, and probably nonobstructed/nonobstructed; experts resolved differences by a consensus reading. These 3 expert categories were compared with the obstructed, equivocal, and nonobstructed interpretations provided by the expert system. Agreement was assessed using weighted κ, and the predictive accuracy of the expert system compared with expert readers was assessed by the area under receiver-operating-characteristic (ROC curve) curves.
Results
The expert system agreed with the consensus reading in 84% (101/120) of nonobstructed kidneys, in 92% (33/36) of obstructed kidneys, and in 45% (13/29) of equivocal kidneys. The weighted κ between the expert system and the consensus reading was 0.72 and was comparable with the weighted κ between experts. There was no significant difference in the areas under the ROC curves when the expert system was compared with each expert using the other 2 experts as the gold standard.
Conclusion
The renal expert system showed good agreement with the expert interpretation and could be a useful educational and decision support tool to assist physicians in the diagnosis of renal obstruction. To better mirror the clinical setting, algorithms to incorporate clinical data must be designed, implemented, and tested.
Background
Since switching to the COBAS® AmpliPrep/COBAS® TaqMan® HIV-1 Test, v. 1.0 from the Amplicor HIV-1 Monitor Test, v. 1.5, an increase in detectable viral load results was noted. We were concerned that this was due to the use of Plasma Preparation Tubes (PPT) in this test.
Objective
To assess the impact of different pre-analytical processing conditions on HIV-1 viral load results on the COBAS® AmpliPrep/COBAS® TaqMan® HIV-1 Test.
Study design
Sixty-three HIV-infected patients were consented and had 3 PPTs and 1 K2EDTA drawn for HIV-1 viral load testing. Three methods of PPT processing were compared against the referent K2EDTA tube which was spun at 1100 × g for 20 min, poured off and frozen; PPT1 was refrigerated with an additional centrifugation prior to testing, PPT2 was processed similarly to EDTA, and PPT3 was centrifuged, frozen and centrifuged again prior to testing.
Results
PPT1 and PPT3 yielded results that were most similar to the referent EDTA processing, with a concordance correlation coefficient (CCC) of 0.80 and 0.85, compared to PPT2 with CCC of 0.37. Both PPT1 and PPT3 involved additional centrifugation prior to testing. In 26 patients with residual samples from the PPT2 processing, 9 (34.6%) were found to have the presence of proviral DNA, which likely contributed to the elevated HIV-1 RNA viral loads in these individuals.
Conclusion
PPTs can be used in the COBAS® AmpliPrep/COBAS® TaqMan® HIV-1 Test with an additional centrifugation in order to avoid misleading elevated HIV-1 RNA viral loads that may change patient management.