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Dive into the research topics where Nancy K. Hills is active.

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Featured researches published by Nancy K. Hills.


Journal of Neurosurgery | 2012

The Barrow Ruptured Aneurysm Trial

Cameron G. McDougall; Robert F. Spetzler; Joseph M. Zabramski; Shahram Partovi; Nancy K. Hills; Peter Nakaji; Felipe C. Albuquerque

OBJECT The purpose of this ongoing study is to compare the safety and efficacy of microsurgical clipping and endovascular coil embolization for the treatment of acutely ruptured cerebral aneurysms and to determine if one treatment is superior to the other by examining clinical and angiographic outcomes. The authors examined the null hypothesis that no difference exists between the 2 treatment modalities in the setting of subarachnoid hemorrhage (SAH). The current report is limited to the clinical results at 1 year after treatment. METHODS The authors screened 725 patients with SAH, resulting in 500 eligible patients who were enrolled prospectively in the study after giving their informed consent. Patients were assigned in an alternating fashion to surgical aneurysm clipping or endovascular coil therapy. Intake evaluations and outcome measurements were collected by nurse practitioners independent of the treating surgeons. Ultimately, 238 patients were assigned to aneurysm clipping and 233 to coil embolization. The 2 treatment groups were well matched. There were no anatomical exclusions. Crossing over was allowed, but primary outcome analysis was based on the initial treatment modality assignment. Posttreatment care was standardized for both groups. Patient outcomes at 1 year were independently assessed using the modified Rankin Scale (mRS). A poor outcome was defined as an mRS score > 2 at 1 year. The primary outcome was based on the assigned group; that is, by intent to treat. RESULTS One year after treatment, 403 patients were available for evaluation. Of these, 358 patients had actually undergone treatment. The remainder either died before treatment or had no identifiable source of SAH. A poor outcome (mRS score > 2) was observed in 33.7% of the patients assigned to aneurysm clipping and in 23.2% of the patients assigned to coil embolization (OR 1.68, 95% CI 1.08-2.61; p = 0.02). Of treated patients assigned to the coil group, 124 (62.3%) of the 199 who were eligible for any treatment actually received endovascular coil embolization. Patients who crossed over from coil to clip treatment fared worse than patients assigned to coil embolization, but no worse than patients assigned to clip occlusion. No patient treated by coil embolization suffered a recurrent hemorrhage. CONCLUSIONS One year after treatment, a policy of intent to treat favoring coil embolization resulted in fewer poor outcomes than clip occlusion. Although most aneurysms assigned to the coil treatment group were treated by coil embolization, a substantial number crossed over to surgical clipping. Although a policy of intent to treat favoring coil embolization resulted in fewer poor outcomes at 1 year, it remains important that high-quality surgical clipping be available as an alternative treatment modality.


The Lancet | 2004

Regression of low-grade squamous intra-epithelial lesions in young women.

Anna-Barbara Moscicki; Stephen Shiboski; Nancy K. Hills; Kimberly Powell; Naomi Jay; Evelyn Hanson; Susanna Miller; Lisa K Canjura-Clayton; Sepidah Farhat; Teresa M. Darragh

BACKGROUND The aim of this study was to assess the probability of low-grade squamous intra-epithelial lesion (LSIL) regression in young women, and to examine the factors associated with this regression. METHODS In a longitudinal study of human papilloma virus (HPV) infection, female adolescents aged 13-22 years were examined every 4 months by cytology, colposcopy, and HPV DNA status. Both prevalent and incident LSIL cases were included in the analysis, with regression defined as at least three consecutive normal Pap smears. FINDINGS Median follow-up time from baseline (defined as the time of first LSIL diagnosis) for the 187 women with LSIL was 61 months (IQR 34-80). Median time they had been sexually active at diagnosis was 3.2 years (2.6-6.5). Probability of regression for the entire cohort was 61% (95% CI 53-70) at 12 months and 91% (84-99) at 36 months of follow-up. No associations were found between LSIL regression and HPV status at baseline, sexual behaviour, contraceptive use, substance or cigarette use, incident sexually transmitted infection, or biopsy. Multivariate analysis showed that only HPV status at the current visit was associated with rate of regression, whether infection was caused by one or more viral types (relative hazard=0.3 [95% CI 0.21-0.42], and 0.14 [0.08-0.25], respectively). INTERPRETATION The high rate of regression recorded in this study lends support to observation by cytology in the management of LSIL in female adolescents. Negative HPV status was associated with regression, suggesting that HPV testing could be helpful in monitoring LSIL.


PLOS ONE | 2013

The relationship of sugar to population-level diabetes prevalence: an econometric analysis of repeated cross-sectional data.

Sanjay Basu; Paula Yoffe; Nancy K. Hills; Robert H. Lustig

While experimental and observational studies suggest that sugar intake is associated with the development of type 2 diabetes, independent of its role in obesity, it is unclear whether alterations in sugar intake can account for differences in diabetes prevalence among overall populations. Using econometric models of repeated cross-sectional data on diabetes and nutritional components of food from 175 countries, we found that every 150 kcal/person/day increase in sugar availability (about one can of soda/day) was associated with increased diabetes prevalence by 1.1% (p <0.001) after testing for potential selection biases and controlling for other food types (including fibers, meats, fruits, oils, cereals), total calories, overweight and obesity, period-effects, and several socioeconomic variables such as aging, urbanization and income. No other food types yielded significant individual associations with diabetes prevalence after controlling for obesity and other confounders. The impact of sugar on diabetes was independent of sedentary behavior and alcohol use, and the effect was modified but not confounded by obesity or overweight. Duration and degree of sugar exposure correlated significantly with diabetes prevalence in a dose-dependent manner, while declines in sugar exposure correlated with significant subsequent declines in diabetes rates independently of other socioeconomic, dietary and obesity prevalence changes. Differences in sugar availability statistically explain variations in diabetes prevalence rates at a population level that are not explained by physical activity, overweight or obesity.


Lancet Oncology | 2013

Effect of comprehensive lifestyle changes on telomerase activity and telomere length in men with biopsy-proven low-risk prostate cancer: 5-year follow-up of a descriptive pilot study

Dean Ornish; Jue Lin; June M. Chan; Elissa S. Epel; Colleen Kemp; Gerdi Weidner; Ruth Marlin; Steven Frenda; Mark Jesus M. Magbanua; Jennifer Daubenmier; Ivette S. Estay; Nancy K. Hills; Nita Chainani-Wu; Peter R. Carroll; Elizabeth H. Blackburn

BACKGROUND Telomere shortness in human beings is a prognostic marker of ageing, disease, and premature morbidity. We previously found an association between 3 months of comprehensive lifestyle changes and increased telomerase activity in human immune-system cells. We followed up participants to investigate long-term effects. METHODS This follow-up study compared ten men and 25 external controls who had biopsy-proven low-risk prostate cancer and had chosen to undergo active surveillance. Eligible participants were enrolled between 2003 and 2007 from previous studies and selected according to the same criteria. Men in the intervention group followed a programme of comprehensive lifestyle changes (diet, activity, stress management, and social support), and the men in the control group underwent active surveillance alone. We took blood samples at 5 years and compared relative telomere length and telomerase enzymatic activity per viable cell with those at baseline, and assessed their relation to the degree of lifestyle changes. FINDINGS Relative telomere length increased from baseline by a median of 0·06 telomere to single-copy gene ratio (T/S)units (IQR-0·05 to 0·11) in the lifestyle intervention group, but decreased in the control group (-0·03 T/S units, -0·05 to 0·03, difference p=0·03). When data from the two groups were combined, adherence to lifestyle changes was significantly associated with relative telomere length after adjustment for age and the length of follow-up (for each percentage point increase in lifestyle adherence score, T/S units increased by 0·07, 95% CI 0·02-0·12, p=0·005). At 5 years, telomerase activity had decreased from baseline by 0·25 (-2·25 to 2·23) units in the lifestyle intervention group, and by 1·08 (-3·25 to 1·86) units in the control group (p=0·64), and was not associated with adherence to lifestyle changes (relative risk 0·93, 95% CI 0·72-1·20, p=0·57). INTERPRETATION Our comprehensive lifestyle intervention was associated with increases in relative telomere length after 5 years of follow-up, compared with controls, in this small pilot study. Larger randomised controlled trials are warranted to confirm this finding. FUNDING US Department of Defense, NIH/NCI, Furlotti Family Foundation, Bahna Foundation, DeJoria Foundation, Walton Family Foundation, Resnick Foundation, Greenbaum Foundation, Natwin Foundation, Safeway Foundation, Prostate Cancer Foundation.


The Journal of Infectious Diseases | 2000

Persistence of Human Papillomavirus Type 16 Infection Is Associated with Lack of Cytotoxic T Lymphocyte Response to the E6 Antigens

Mayumi Nakagawa; Daniel P. Stites; Sandeep Patel; Sepideh Farhat; Mark E. Scott; Nancy K. Hills; Joel M. Palefsky; Anna-Barbara Moscicki

Our cross-sectional study suggested that cytotoxic T lymphocyte (CTL) responses have a protective effect in squamous intraepithelial lesion (SIL) development. More CTL responses in women with human papillomavirus type 16 (HPV 16) infection without SILs than with SILs were detected. In the current longitudinal study, the role of CTL in clearing HPV 16 infection in women without SILs was investigated. Women with HPV 16 infection (n=51) were enrolled, along with HPV 16-negative control women (n=3). Twenty-two (55%) of 40 women who cleared HPV 16 infection had an E6 CTL response at least once, compared with none of 9 women who had HPV 16 persistence (P=.003). Such a difference was not demonstrated for E7; 25 (63%) of 40 women who cleared HPV 16 infection responded, versus 5 (56%) of 9 women with persistence (P=.720). It appears that lack of response to E6 is important in the persistence of HPV 16 infection.


Journal of Neurosurgery | 2015

The Barrow Ruptured Aneurysm Trial: 6-year results.

Robert F. Spetzler; Cameron G. McDougall; Joseph M. Zabramski; Felipe C. Albuquerque; Nancy K. Hills; Jonathan J. Russin; Shahram Partovi; Peter Nakaji; Robert C. Wallace

OBJECT The authors report the 6-year results of the Barrow Ruptured Aneurysm Trial (BRAT). This ongoing randomized trial, with the final goal of a 10-year follow-up, compares the safety and efficacy of surgical clip occlusion and endovascular coil embolization in patients presenting with subarachnoid hemorrhage (SAH) from a ruptured aneurysm. The 1- and 3-year results of this trial have been previously reported. METHODS In total, 500 patients with an SAH met the entry criteria and were enrolled in the study. Of these patients, 471 were randomly assigned to the treatments: 238 to surgical clipping and 233 to endovascular coiling. Six patients who died before treatment and 57 patients with nonaneurysmal SAHs were excluded, leaving a total of 408 patients who underwent clipping (209 assigned) or coiling (199 assigned). Whether to treat patients within the assigned group or to cross over patients to the other group was at the discretion of the treating physician; 38% (75/199) of the patients assigned to coiling were crossed over to clipping and 1.9% (4/209) assigned to clipping were crossed over to coiling. The outcome data were collected by a dedicated nurse practitioner. The primary outcome analysis was based on the assigned treatment group; poor outcome was defined as a modified Rankin Scale (mRS) score > 2 and was independently adjudicated. Six years after randomization, 336 (82%) of 408 patients who had been treated were available for examination. RESULTS On the basis of an mRS score of > 2, and similar to the results at the 3-year follow-up, no significant difference in outcomes (p = 0.24) was detected between the 2 treatment groups. Complete aneurysm obliteration at 6 years was achieved in 96% (111/116) of the clipping group and in 48% (23/48) of the coiling group (p < 0.0001). In the period between the 3- and 6-year follow-ups, 3 additional patients assigned to coiling and none assigned to clipping received retreatment, for overall retreatment rates of 4.6% (13/280) for clipping and 16.4% (21/128) for coiling (p < 0.0001). When aneurysm location was considered, the 6-year results continued to match the previously reported results, with no difference in outcome for anterior circulation aneurysms at most time points. Of the anterior circulation aneurysms assigned to coiling treatment, 42% (70/168) were crossed over to clipping treatment. The outcomes for posterior circulation aneurysms continued to favor coiling. The randomization process was unexpectedly skewed, with 18 of 21 treated aneurysms of the posterior inferior cerebellar artery (PICA) being assigned to clipping, but even when PICA aneurysms were removed from the analysis, outcomes for the posterior circulation aneurysms still favored coiling. CONCLUSIONS Although BRAT was statistically underpowered to detect small differences, these results suggest little difference in outcome between the 2 treatments for anterior circulation aneurysms. This was not the case for the posterior circulation aneurysms, where coil embolization appeared to provide a sustained advantage over clipping. Aneurysm obliteration rates in BRAT were significantly lower and retreatment rates significantly higher in the patients undergoing coiling than in those undergoing clipping. However, despite the fact that retreatment rates were higher after coiling, no recurrent hemorrhages were known to have occurred in patients undergoing coiling in BRAT who were followed up for 6 years. Sufficient questions remain about the relative benefits of the 2 treatment modalities to warrant further well-designed randomized trials.


Stroke | 2012

Statin Use During Ischemic Stroke Hospitalization Is Strongly Associated With Improved Poststroke Survival

Alexander C. Flint; Hooman Kamel; Babak B. Navi; Vivek A. Rao; Bonnie Faigeles; Carol Conell; Jeff Klingman; Stephen Sidney; Nancy K. Hills; Michael Sorel; Sean P. Cullen; S. Claiborne Johnston

Background and Purpose— Statins reduce infarct size in animal models of stroke and have been hypothesized to improve clinical outcomes after ischemic stroke. We examined the relationship between statin use before and during stroke hospitalization and poststroke survival. Methods— We analyzed records from 12 689 patients admitted with ischemic stroke to any of 17 hospitals in a large integrated healthcare delivery system between January 2000 and December 2007. We used multivariable survival analysis and grouped-treatment analysis, an instrumental variable method that uses treatment differences between facilities to avoid individual patient-level confounding. Results— Statin use before ischemic stroke hospitalization was associated with improved survival (hazard ratio, 0.85; 95% CI, 0.79–0.93; P<0.001), and use before and during hospitalization was associated with better rates of survival (hazard ratio, 0.59; 95% CI, 0.53–0.65; P<0.001). Patients taking a statin before their stroke who underwent statin withdrawal in the hospital had a substantially greater risk of death (hazard ratio, 2.5; 95% CI, 2.1–2.9; P<0.001). The benefit was greater for high-dose (>60 mg/day) statin use (hazard ratio, 0.43; 95% CI, 0.34–0.53; P<0.001) than for lower dose (<60 mg/day) statin use (hazard ratio, 0.60; 95% CI, 0.54–0.67; P<0.001; test for trend P<0.001), and earlier treatment in-hospital further improved survival. Grouped-treatment analysis showed that the association between statin use and survival cannot be explained by patient-level confounding. Conclusions— Statin use early in stroke hospitalization is strongly associated with improved poststroke survival, and statin withdrawal in the hospital, even for a brief period, is associated with worsened survival.


Cerebrovascular Diseases | 2006

NIH Stroke Scale Reliability in Ratings from a Large Sample of Clinicians

S. Andrew Josephson; Nancy K. Hills; S. Claiborne Johnston

Objective: The NIH Stroke Scale (NIHSS) is widely used in stroke clinical care and trials. Certification in its use, most commonly through rating of video vignettes, is routinely required. To investigate the reliability of the NIHSS in a representative sample of raters, we examined the results of the most frequently used certification examination. Methods: At the invitation of the National Stroke Association, we analyzed the results of all raters who completed one of two multiple patient videotaped certification examinations from 1998 to 2004. Total scores for each vignette were calculated and ratings were compared based on percentile of responses and modified kappa scores. Results: There were 7,405 unique raters with 38,148 individual NIHSS item responses; median scores for each vignette ranged from 0 to 31. Total NIHSS scores varied widely between raters; scoring for 7 of the 11 patients (64%) had a four or more point difference in NIHSS score from the 5th to 95th percentile. The aphasia (kappa = 0.60) and facial palsy (0.65) items on the test contributed most to the variance in the total NIHSS score. Nurses agreed with the most common response on scoring more frequently than physicians (p < 0.0001). Taking the certification examination multiple times did not improve agreement. Conclusions: In a large diverse sample of clinicians, inter-rater reliability for individual elements of the NIHSS on videotaped vignettes was generally good, but overall scoring was inconsistent and could impact clinical trial results. Whether additional training, modification of examination elements, or clearer definitions for scoring could improve reliability requires further study.


Brain | 2011

Training of goal-directed attention regulation enhances control over neural processing for individuals with brain injury

Anthony J.-W. Chen; Tatjana Novakovic-Agopian; Terrence J. Nycum; Shawn Song; Gary R. Turner; Nancy K. Hills; Scott Rome; Gary Abrams; Mark D’Esposito

Deficits in attention and executive control are some of the most common, debilitating and persistent consequences of brain injuries. Understanding neural mechanisms that support clinically significant improvements, when they do occur, may help advance treatment development. Intervening via rehabilitation provides an opportunity to probe such mechanisms. Our objective was to identify neural mechanisms that underlie improvements in attention and executive control with rehabilitation training. We tested the hypothesis that intensive training enhances modulatory control of neural processing of perceptual information in patients with acquired brain injuries. Patients (n=12) participated either in standardized training designed to target goal-directed attention regulation, or a comparison condition (brief education). Training resulted in significant improvements on behavioural measures of attention and executive control. Functional magnetic resonance imaging methods adapted for testing the effects of intervention for patients with varied injury pathology were used to index modulatory control of neural processing. Pattern classification was utilized to decode individual functional magnetic resonance imaging data acquired during a visual selective attention task. Results showed that modulation of neural processing in extrastriate cortex was significantly enhanced by attention regulation training. Neural changes in prefrontal cortex, a candidate mediator for attention regulation, appeared to depend on individual baseline state. These behavioural and neural effects did not occur with the comparison condition. These results suggest that enhanced modulatory control over visual processing and a rebalancing of prefrontal functioning may underlie improvements in attention and executive control.


Journal of Head Trauma Rehabilitation | 2011

Rehabilitation of executive functioning with training in attention regulation applied to individually defined goals: a pilot study bridging theory, assessment, and treatment.

Tatjana Novakovic-Agopian; Anthony J.-W. Chen; Scott Rome; Gary Abrams; Holli Castelli; Annemarie Rossi; Ryan McKim; Nancy K. Hills; Mark DʼEsposito

Objective:To assess feasibility and effects of training in goal-oriented attentional self-regulation for patients with brain injury and chronic executive dysfunction. Participants:Sixteen individuals with chronic brain injury and mild to moderate executive dysfunction. Design:Participants were divided into 2 groups: one group completed goal-oriented attentional self-regulation training during the first 5 weeks, followed by a brief (2-hour) educational instruction session as a control midway through the second 5 weeks; the other group participated in reverse order. Measures:Neuropsychological and functional performance assessed at baseline and at weeks 5 and 10. Results:Participants found training in goal-oriented attentional self-regulation engaging, incorporated some trained strategies into daily life, and reported subjective improvements in personal functioning. At week 5, participants who completed goals training significantly improved on tests of attention and executive function and had fewer functional task failures, while performance did not change after educational instruction. At week 10, participants who crossed over from educational instruction to goals training also significantly improved on attention and executive function tests. Participants who crossed from goals training to educational instruction maintained their week 5 gains. Conclusions:Training in goal-oriented attentional self-regulation is theoretically driven and feasible in a research setting. Pilot results suggest improvements in cognitive and functional domains targeted by the intervention.

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S. Claiborne Johnston

University of Texas at Austin

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