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Background Parkinson’s Disease patients with predominant gait dysfunction appear to have reduced cortical thickness compared to other motor phenotypes. The extent to which advancing age or disease duration impact the pattern of these distinctions is unclear. Objective We examine if PD patients with predominant signs of postural instability and gait dysfunction are distinguished by distinct patterns of cerebral atrophy, and how these differences are influenced by age and disease duration. Methods The Unified Parkinson’s Disease Rating Score (UPDRS) was administered to 196 PD patients (age = 61.4 ± 8.9 yrs) in the Off and On dopamine state. All completed a structural T1-weighted brain MRI. We defined 3 motor phenotypes: tremor dominant, akinetic-rigid, and postural instability with gait disorder. General linear modeling quantified cortical thickness in relation to disease duration, and motor improvement after dopaminergic therapy. Cortical thickness and subcortical volumes were compared between the three motor subtypes, after controlling for disease duration and age. Results We identified 177/196 patients who met criteria for a motor subtype. When corrected for disease duration, postural-instability patients had marked cortical thinning of the bilateral frontal-temporal and posterior cortical regions (cuneus/precuneus). After regressing for age, reduced frontal thickness was evident in patients with gait dysfunction. Widespread cortical thinning was associated with increasing disease duration and reduced motor improvement to dopaminergic therapy. Conclusions Results emphasize that the profile of motor signs, especially prominent gait manifestations, relate to cortical thinning in distinct regions. Unique patterns of atrophy appear to be driven by advancing pathology related to age and disease duration.

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Purpose Major cancer surgeries have regionalized to fewer and higher‐volume hospitals, with the goal of improving the quality of surgical care. However, regionalization may have negative effects on geographic access to care. We hypothesize that lung cancer patients have been traveling further for surgery over time as regionalization has occurred, and this increased travel has primarily impacted rural patients. Methods A North Carolina all‐payer state discharge database was used to capture discharges from 2005 to 2015 for patients undergoing lung cancer resection. Changes in patterns of care over time in high‐volume centers (HVC) were examined. Adjusted patient straight‐line travel distance was estimated over time and stratified by rural‐urban location. Findings The number of hospitals performing lung cancer resections decreased from 49 to 31 over the study period (P = .0006), and the proportion of patients receiving care at HVC increased from 23% to 44% (P < .0001). Rural patient travel distance increased over time by 8.5 miles (95% CI: 0.56‐17.10, P = .048), from 45.1 to 53.6 miles. There was no change in urban patient travel distance. The difference in adjusted travel distance between rural and urban patients nearly doubled from 2005 to 2015 (9.6 to 17.9 miles,P < .0001). Conclusion In North Carolina, lung cancer surgical regionalization occurred over the study period and was accompanied by increases in travel distance for rural patients only. Further work is needed to determine the effects of greater travel distance on patterns of cancer care for rural patients.

Advancing age and disease duration both contribute to cortical thinning in Parkinson’s disease (PD), but the pathological interactions between them are poorly described. This study aims to distinguish patterns of cortical decline determined by advancing age and disease duration in PD. A convenience cohort of 177 consecutive PD patients, identified at the Vanderbilt University Movement Disorders Clinic as part of a clinical evaluation for Deep Brain Stimulation (age: M= 62.0, SD 9.3), completed a standardized clinical assessment, along with structural brain Magnetic Resonance Imaging scan. Age and gender matched controls (n=53) were obtained from the Alzheimer Disease Neuroimaging Initiative and Progressive Parkinson’s Marker Initiative (age: M= 63.4, SD 12.2). Estimated changes in cortical thickness were modeled with advancing age, disease duration, and their interaction. The best-fitting model, linear or curvilinear (2nd, or 3rd order natural spline), was defined using the minimum Akaike Information Criterion, and illustrated on a 3-dimensional brain. Three curvilinear patterns of cortical thinning were identified: early decline, late decline, and early-stable-late. In contrast to healthy controls, the best-fit model for age related changes in PD is curvilinear (early decline), particularly in frontal and precuneus regions. With advancing disease duration, a curvilinear model depicts accelerating decline in the occipital cortex. A significant interaction between advancing age and disease duration is evident in frontal, motor, and posterior parietal areas. Study results support the hypothesis that advancing age and disease duration differentially affect regional cortical thickness and display regional dependent linear and curvilinear patterns of thinning.