Age-Related Brain Atrophy and the Positive Effects of Behavioral Enrichment in Middle-Aged Beagles.

Aging dogs serve as a valuable preclinical model for Alzheimer's disease (AD) due to their natural age-related development of ß-amyloid (Aß) plaques, human-like metabolism, and large brains that are ideal for studying structural brain aging trajectories from serial neuroimaging. Here we examined the effects of chronic treatment with the calcineurin inhibitor (CNI) tacrolimus or the nuclear factor of activated T cells (NFAT)-inhibiting compound Q134R on age-related canine brain atrophy from a longitudinal study in middle-aged beagles (36 females, 7 males) undergoing behavioral enrichment. Annual MRI was analyzed using modern, automated techniques for region-of-interest-based and voxel-based volumetric assessments. We found that the frontal lobe showed accelerated atrophy with age, while the caudate nucleus remained relatively stable. Remarkably, the hippocampus increased in volume in all dogs. None of these changes were influenced by tacrolimus or Q134R treatment. Our results suggest that behavioral enrichment can prevent atrophy and increase the volume of the hippocampus but does not prevent aging-associated prefrontal cortex atrophy.

Incidence, Risk Factors, and Trends of Motor Peripheral Nerve Injury After Colorectal Surgery: Analysis of the National Surgical Quality Improvement Program Database.

BACKGROUND: Motor peripheral nerve injury is a rare but serious event after colorectal surgery, and a nationwide study of this complication is lacking. OBJECTIVE: The purpose of this study was to report the incidence, trends, and risk factors of motor peripheral nerve injury during colorectal surgery. DESIGN: The National Surgical Quality Improvement Program database was surveyed for motor peripheral nerve injury complicating colorectal procedures. Risk factors for this complication were identified using logistic regression analysis. SETTINGS: The study used a national database. PATIENTS: Patients undergoing colorectal resection between 2005 and 2013 were included. MAIN OUTCOME MEASURES: The incidence, trends, and risk factors for motor peripheral nerve injury complicating colorectal procedures were measured. RESULTS: We identified 186,936 colorectal cases, of which 50,470 (27%) were performed laparoscopically. Motor peripheral nerve injury occurred in 122 patients (0.065%). Injury rates declined over the study period, from 0.025% in 2006 to <0.010% in 2013 (p < 0.001). Patients with motor peripheral nerve injury were younger (mean ± SD; 54.02 ± 15.41 y vs 61.56 ± 15.95 y; p < 0.001), more likely to be obese (BMI ≥30; 43% vs 31%; p = 0.003), and more likely to have received radiotherapy (12.3% vs 4.7%; p < 0.001). Nerve injury was also associated with longer operative times (277.16 ± 169.79 min vs 176.69 ± 104.80 min; p < 0.001) and was less likely to be associated with laparoscopy (p = 0.043). Multivariate analysis revealed that increasing operative time was associated with nerve injury (OR = 1.04 (95% CI, 1.03-1.04)), whereas increasing age was associated with a protective effect (OR = 0.80 (95% CI, 0.71-0.90)). LIMITATIONS: This study was limited by its retrospective nature. CONCLUSIONS: Motor peripheral nerve injury during colorectal procedures is uncommon (0.065%), and its rate declined significantly over the study period. Prolonged operative time is the strongest predictor of motor peripheral nerve injury during colorectal procedures. Instituting and documenting measures to prevent nerve injury is imperative; however, special attention to this complication is necessary when surgeons contemplate long colorectal procedures.

Volume and outcomes relationship in laparoscopic diaphragmatic hernia repair.

BACKGROUND: There is no published data regarding the relationship between hospital volume and outcomes in patients undergoing laparoscopic diaphragmatic hernia repair. We hypothesize that hospitals performing high case volume have improved outcomes compared to low-volume hospitals. MATERIALS AND METHODS: We reviewed the National Inpatient Sample (NIS) database between 2008 and 2012 for adults with the diagnosis of diaphragmatic hernia who underwent elective laparoscopic repair of diaphragmatic Hernia and/or Nissen fundoplication. Pediatric, emergent, and open cases were excluded. Main outcome measures included logistic regression analysis of factors predictive of in-hospital mortality and outcomes according to annual hospital case volume. RESULTS: A total of 31,228 laparoscopic diaphragmatic hernia operations were analyzed. The overall in-hospital mortality was 0.14%. Risk factors for higher in-hospital mortality included renal failure (AOR: 6.26; 95% CI: 2.48-15.78; p < 0.001), age>60 years (AOR: 5.06; 95% CI: 2.38-10.76; p < 0.001), and CHF (AOR: 3.80; 95% CI: 1.39-10.38; p = 0.009) while an incremental increase in volume of 10 cases/year (AOR: 0.89; 95% CI: 0.81-0.98; p = 0.019) and diabetes (AOR: 0.34; 95% CI: 0.12-0.93; p = 0.036) decreases mortality. There was a small but significant inverse relationship between hospital case volume and mortality with a 10% reduction in adjusted odds of in-hospital mortality for every increase in 10 cases per year. Using 10 cases per year as the volume threshold, low-volume hospitals (≤10 cases/year) had almost a twofold higher mortality compared to high-volume hospitals (0.23 vs. 0.12%, respectively, p = 0.02). CONCLUSIONS: There was a small but significant inverse relationship between the hospitals' case volume and mortality in laparoscopic diaphragmatic hernia repair.

Trends in utilization of bariatric surgery, 2009-2012.

BACKGROUND: Utilization of bariatric surgery has changed dramatically over the past two decades. The aim of this study was to update the trends in volume and procedural type of bariatric surgery in the USA. Data were derived from the National Inpatient Sample from 2009 through 2012. METHODS: We used ICD-9 diagnosis and procedural codes to identify all hospitalizations during which a bariatric procedure was performed for the treatment of severe obesity. The data were reviewed for patient demographics and characteristics, annual number of bariatric operations, and specific procedural types and proportion of laparoscopic cases. The US Census data were used to calculate the population-based annual rate of bariatric surgery per 100,000 adults. RESULTS: Between 2009 and 2012, the number of inpatient bariatric operations ranged between 81,005 and 114,780 cases annually. During this time period, the annual rate of bariatric procedures was highest for 2012 at 47.3 procedures per 100,000 adults. The bariatric surgery approach most commonly performed continues to be laparoscopic, ranging between 93.1 and 97.1 %. In 2012, there was a precipitous reduction in the number of gastric bypass and gastric banding operations and replaced by an increase in the number of sleeve gastrectomy operation. The in-hospital mortality rate remains low, ranging from 0.07 to 0.10 %. CONCLUSIONS: In the USA, the annual volume of inpatient bariatric surgery continues to be stable. Utilization of the laparoscopic approach to bariatric surgery remains high, while the in-hospital mortality continues to be low at ≤0.10 % throughout the 4-year period.

Laparoscopic right hemicolectomy: short- and long-term outcomes of intracorporeal versus extracorporeal anastomosis.

BACKGROUND: The use of laparoscopy for right hemicolectomy has gained popularity allowing the option of a totally laparoscopic intracorporeal anastomosis (IA) for intestinal reconstruction. This technique may alleviate some of the technical limitations that a surgeon faces with a laparoscopic-assisted extracorporeal anastomosis (EA). METHODS: A retrospective chart review of 195 consecutive patients who underwent laparoscopic right hemicolectomy by four colorectal surgeons at three institutions from March 2005 to June 2014 was performed. Multivariate regression analysis was used to compare postoperative and oncologic outcomes. RESULTS: A total of 195 patients underwent laparoscopic right hemicolectomy over the study period, with 86 (44 %) patients receiving IA and 109 (56 %) patients receiving an EA. The most common indication for surgery in both groups was cancer: 56 (65 %) of IA cases and 57 (52 %) of EA cases. IA had a significantly higher rate of minor complications but no difference in serious complications compared to EA. Conversion to open resection was higher in EA. Using multivariate analysis to compare IA versus EA, there was no significant difference in length of stay, return of bowel function, risk of anastomotic leak, risk of intraabdominal abscess or risk of wound complications. Amongst cancer resections, there was no significant difference in the median number of lymph nodes harvested (18 LNs in IA group vs. 19 LNs in EA group, P > 0.05). There was also no significant difference in overall survival and disease-free survival at 5.7 years between the two groups. CONCLUSIONS: IA in laparoscopic right hemicolectomy is associated with similar postoperative and oncologic outcomes compared to EA. IA may possess advantages in terms of conversion and flexibility of specimen extraction, but this is counterbalanced by a higher incidence of minor complications. These findings suggest that IA represents a valid technique in the arsenal of the experienced colorectal surgeon without compromising outcomes.

Impact of Hospital Population Case-Mix, Including Poverty, on Hospital All-Cause and Infection-Related 30-Day Readmission Rates.

BACKGROUND: Reducing hospital readmissions, including preventable healthcare-associated infections, is a national priority. The proportion of readmissions due to infections is not well-understood. Better understanding of hospital risk factors for readmissions and infection-related readmissions may help optimize interventions to prevent readmissions. METHODS: Retrospective cohort study of California acute care hospitals and their patient populations discharged between 2009 and 2011. Demographics, comorbidities, and socioeconomic status were entered into a hierarchical generalized linear mixed model predicting all-cause and infection-related readmissions. Crude verses adjusted hospital rankings were compared using Cohen's kappa. RESULTS: We assessed 30-day readmission rates from 323 hospitals, accounting for 213 879 194 post-discharge person-days of follow-up. Infection-related readmissions represented 28% of all readmissions and were associated with discharging a high proportion of patients to skilled nursing facilities. Hospitals serving populations with high proportions of males, comorbidities, prolonged length of stay, and populations living in a federal poverty area, had higher all-cause and infection-related readmission rates. Academic hospitals had higher all-cause and infection-related readmission rates (odds ratio 1.24 and 1.15, respectively). When comparing adjusted vs crude hospital rankings for infection-related readmission rates, adjustment revealed 31% of hospitals changed performance category for infection-related readmissions. CONCLUSIONS: Infection-related readmissions accounted for nearly 30% of all-cause readmissions. High hospital infection-related readmissions were associated with serving a high proportion of patients with comorbidities, long lengths of stay, discharge to skilled nursing facility, and those living in federal poverty areas. Preventability of these infections needs to be assessed.

Surgical treatments for rectal prolapse: how does a perineal approach compare in the laparoscopic era?

BACKGROUND: Patients with rectal prolapse often have significant comorbidities that lead surgeons to select a perineal resection for treatment despite a reported higher recurrence rate over abdominal approaches. There is a lack of data to support this practice in the laparoscopic era. The objective of this study was to evaluate if risk-adjusted morbidity of perineal surgery for rectal prolapse is actually lower than laparoscopic surgery. DESIGN: A retrospective review of the American College of Surgeons National Surgical Quality Improvement Program (NSQIP) database as performed for patients undergoing surgical treatment of rectal prolapse between 2005 and 2011. Outcomes were analyzed according to procedure-type: laparoscopic rectopexy (LR), laparoscopic resection/rectopexy (LRR), open rectopexy (OR), open resection/rectopexy (ORR), and perineal resection (PR). A multivariate logistic regression was used to compare risk-adjusted morbidity and mortality between each procedure. Main outcome measures were 30-day morbidity and mortality. RESULTS: Among 3,254 cases sampled, a laparoscopic approach was used in 22 %, an open abdominal approach in 30 %, and PR in 48 %. Patients undergoing PR were older (76) and had a higher ASA (3) compared to laparoscopic (58, 2) and open abdominal procedures (58, 2). Risk-adjusted mortality could not be assessed due to a low overall incidence of mortality (0.01 %). Overall morbidity was 9.3 %. ORR was associated with a higher risk-adjusted morbidity compared to PR (OR: 1.89 CI (1.19-2.99), p = 0.03). There were no significant differences in risk-adjusted morbidity found between LR and LRR compared to PR (OR 0.44 CI (0.19-1.03), p = 0.18; OR 1.55 CI (0.86-2.77), p = 0.18). Laparoscopic cases averaged 27 min longer than open cases (p < 0.001). CONCLUSION: Laparoscopic rectal prolapse surgery has comparable morbidity and mortality to perineal surgery. A randomized trial is indicated to validate these findings and to assess recurrence rates and functional outcomes.

A decade analysis of trends and outcomes of partial versus total esophagectomy in the United States.

OBJECTIVE: To examine the trends and outcomes of partial esophagectomy with an intrathoracic anastomosis compared with total esophagectomy with a cervical anastomosis. BACKGROUND: Controversy exists regarding the optimal surgical approach in the management of esophageal cancer. METHODS: Using the Nationwide Inpatient Sample database, yearly trends of patients with esophageal cancer who underwent partial and total esophagectomy were analyzed. Multivariate logistic regression analysis was used to analyze serious morbidity and in-hospital mortality between partial and total esophagectomy. In addition, outcomes were analyzed according to hospital volume, with low-volume centers defined as those with fewer than 10 cases per year and high-volume centers as those with 10 or more cases per year. RESULTS: Between 2001 and 2010, 15,190 esophagectomies were performed for cancer. There was an overall increase in the number of esophagectomy procedures performed (1402 to 1975), with a concomitant reduction in the mortality rate (8.3% to 4.2%), particularly for partial esophagectomy. Partial esophagectomy was the predominant operation (76%). Most operations were performed at low-volume centers (62%), with a recent shift of cases to high-volume center. Compared with total esophagectomy, partial esophagectomy was associated with a shorter length of hospital stay (16 ± 6 vs 19 ± 9 days; P < 0.05), a lower in-hospital mortality rate (5.8% vs 8.3%; P < 0.05), and a lower hospital charge ($119,339 vs $138,496; P < 0.05). On multivariate regression analysis, total esophagectomy was associated with higher serious morbidity (odds ratio, 1.39; P < 0.01) and in-hospital mortality (odds ratio, 1.67; P = 0.03). There were no significant differences in risk-adjusted outcomes between low-volume centers and high-volume center. CONCLUSIONS: The number of esophagectomies performed for esophageal cancer has increased over the past decade accompanied by an overall reduction in mortality, particularly for the partial esophagectomy approach. The predominant operation in the United States continues to be partial esophagectomy with an intrathoracic anastomosis, which was associated with lower morbidity and in-hospital mortality than total esophagectomy. Hospital volume at a threshold of 10 cases per year was not a predictor of outcome.

Dementia is associated with medial temporal atrophy even after accounting for neuropathologies.

Brain atrophy is associated with degenerative neuropathologies and the clinical status of dementia. Whether dementia is associated with atrophy independent of neuropathologies is not known. In this study, we examined the pattern of atrophy associated with dementia while accounting for the most common dementia-related neuropathologies. We used data from National Alzheimer's Coordinating Center (n = 129) and Alzheimer's Disease Neuroimaging Initiative (n = 47) participants with suitable in vivo 3D-T1w MRI and autopsy data. We determined dementia status at the visit closest to MRI. We examined the following dichotomized neuropathological variables: Alzheimer's disease neuropathology, hippocampal sclerosis, Lewy bodies, cerebral amyloid angiopathy and atherosclerosis. Voxel-based morphometry identified areas associated with dementia after accounting for neuropathologies. Identified regions of interest were further analysed. We used multiple linear regression models adjusted for neuropathologies and demographic variables. We also examined models with dementia and Clinical Dementia Rating sum of the boxes as the outcome and explored the potential mediating effect of medial temporal lobe structure volumes on the relationship between pathology and cognition. We found strong associations for dementia with volumes of the hippocampus, amygdala and parahippocampus (semi-partial correlations ≥ 0.28, P < 0.0001 for all regions in National Alzheimer's Coordinating Center; semi-partial correlations ≥ 0.35, P ≤ 0.01 for hippocampus and parahippocampus in Alzheimer's Disease Neuroimaging Initiative). Dementia status accounted for more unique variance in atrophy in these structures (∼8%) compared with neuropathological variables; the only exception was hippocampal sclerosis which accounted for more variance in hippocampal atrophy (10%). We also found that the volumes of the medial temporal lobe structures contributed towards explaining the variance in Clinical Dementia Rating sum of the boxes (ranging from 5% to 9%) independent of neuropathologies and partially mediated the association between Alzheimer's disease neuropathology and cognition. Even after accounting for the most common neuropathologies, dementia still had among the strongest associations with atrophy of medial temporal lobe structures. This suggests that atrophy of the medial temporal lobe is most related to the clinical status of dementia rather than Alzheimer's disease or other neuropathologies, with the potential exception of hippocampal sclerosis.

Joint-label fusion brain atlases for dementia research in Down syndrome.

Research suggests a link between Alzheimer's Disease in Down Syndrome (DS) and the overproduction of amyloid plaques. Using Positron Emission Tomography (PET) we can assess the in-vivo regional amyloid load using several available ligands. To measure amyloid distributions in specific brain regions, a brain atlas is used. A popular method of creating a brain atlas is to segment a participant's structural Magnetic Resonance Imaging (MRI) scan. Acquiring an MRI is often challenging in intellectually-imparied populations because of contraindications or data exclusion due to significant motion artifacts or incomplete sequences related to general discomfort. When an MRI cannot be acquired, it is typically replaced with a standardized brain atlas derived from neurotypical populations (i.e. healthy individuals without DS) which may be inappropriate for use in DS. In this project, we create a series of disease and diagnosis-specific (cognitively stable (CS-DS), mild cognitive impairment (MCI-DS), and dementia (DEM-DS)) probabilistic group atlases of participants with DS and evaluate their accuracy of quantifying regional amyloid load compared to the individually-based MRI segmentations. Further, we compare the diagnostic-specific atlases with a probabilistic atlas constructed from similar-aged cognitively-stable neurotypical participants. We hypothesized that regional PET signals will best match the individually-based MRI segmentations by using DS group atlases that aligns with a participant's disorder and disease status (e.g. DS and MCI-DS). Our results vary by brain region but generally show that using a disorder-specific atlas in DS better matches the individually-based MRI segmentations than using an atlas constructed from cognitively-stable neurotypical participants. We found no additional benefit of using diagnose-specific atlases matching disease status. All atlases are made publicly available for the research community. Highlight: Down syndrome (DS) joint-label-fusion atlases provide accurate positron emission tomography (PET) amyloid measurements.A disorder-specific DS atlas is better than a neurotypical atlas for PET quantification.It is not necessary to use a disease-state-specific atlas for quantification in aged DS.Dorsal striatum results vary, possibly due to this region and dementia progression.

Improved survival with adjuvant chemotherapy in locally advanced rectal cancer patients treated with preoperative chemoradiation regardless of pathologic response.

OBJECTIVE: The aim of this study is to examine the effect of postoperative chemotherapy on survival in patients with stage II or III rectal adenocarcinoma who undergo neoadjuvant chemoradiation (CRT) and surgical resection. METHODS: A retrospective review of the National Cancer Database (NCDB) from 2006 to 2013 was performed. Cases were analyzed based on pathologic complete response (pCR) status and use of adjuvant therapy. The Kaplan-Meier method was used to estimate overall survival probabilities. RESULTS: 23,045 cases were identified, of which 5832 (25.31%) achieved pCR. In the pCR group, 1513 (25.9%) received adjuvant chemotherapy, and in the non-pCR group, 5966 (34.7%) received adjuvant therapy. In the pCR group, five-year survival probability was 87% (95% CI 84%-89%) with adjuvant therapy and 81% (95% CI 79%-82%) without adjuvant therapy. In the non-pCR group, five-year survival probability was 78% (95% CI 76%-79%) with adjuvant therapy and 70% (95% CI 69%-71%) without adjuvant therapy. In the non-pCR and node-negative subgroup (ypN-), five-year survival probability was 86% (95% CI 84%-88%) with adjuvant therapy and 76% (95% CI 74%-77%) without adjuvant therapy. In the non-pCR and node-positive subgroup (ypN+), five-year survival probability was 67% (95% CI 65%-70%) with adjuvant therapy and 60% (95% CI 58%-63%) without adjuvant therapy. CONCLUSIONS: Adjuvant chemotherapy in stage II or III rectal adenocarcinoma is associated with increased five-year survival probability regardless of pCR status. We observed similar survival outcomes among non-pCR ypN- treated with adjuvant chemotherapy compared with patients achieving pCR treated with adjuvant chemotherapy.

Brain amyloid and the transition to dementia in Down syndrome.

INTRODUCTION: Down syndrome (DS) is associated with elevated risk for Alzheimer's disease (AD) due to amyloid beta (Aß) lifelong accumulation. We hypothesized that the spatial distribution of brain Aß predicts future dementia conversion in individuals with DS. METHODS: We acquired 18F-florbetapir positron emission tomography scans from 19 nondemented individuals with DS at baseline and monitored them for 4 years, with five individuals transitioning to dementia. Machine learning classification using an independent test set determined features on 18F-florbetapir standardized uptake value ratio maps that predicted transition. RESULTS: In addition to "AD signature" regions including the inferior parietal cortex, temporal lobes, and the cingulum, we found that Aß cortical binding in the prefrontal and superior frontal cortices distinguished subjects who transitioned to dementia. Classification did well in predicting transitioners. DISCUSSION: Our study suggests that specific regional profiles of brain amyloid in older adults with DS may predict cognitive decline and are informative in evaluating the risk for dementia.

Down syndrome: Distribution of brain amyloid in mild cognitive impairment.

INTRODUCTION: Down syndrome (DS) is associated with a higher risk of dementia. We hypothesize that amyloid beta (Aß) in specific brain regions differentiates mild cognitive impairment in DS (MCI-DS) and test these hypotheses using cross-sectional and longitudinal data. METHODS: 18F-AV-45 (florbetapir) positron emission tomography (PET) data were collected to analyze amyloid burden in 58 participants clinically classified as cognitively stable (CS) or MCI-DS and 12 longitudinal CS participants. RESULTS: The study confirmed our hypotheses of increased amyloid in inferior parietal, lateral occipital, and superior frontal regions as the main effects differentiating MCI-DS from the CS groups. The largest annualized amyloid increases in longitudinal CS data were in the rostral middle frontal, superior frontal, superior/middle temporal, and posterior cingulate cortices. DISCUSSION: This study helps us to understand amyloid in the MCI-DS transitional state between cognitively stable aging and frank dementia in DS. The spatial distribution of Aß may be a reliable indicator of MCI-DS in DS.

Randomized Clinical Trial of Epidural Compared with Conventional Analgesia after Minimally Invasive Colorectal Surgery.

BACKGROUND: The effectiveness of thoracic epidural analgesia (EA) vs conventional IV analgesia (IA) after minimally invasive surgery is still unproven. We designed a randomized controlled trial comparing EA with IA after minimally invasive colorectal surgery. STUDY DESIGN: A total of 87 patients who underwent minimally invasive colorectal procedures at a single institution between 2011 and 2014 were enrolled. Eight patients were excluded and 38 were randomized to EA and 41 to IA. Pain was assessed with the Visual Analogue Scale and quality of life with the Overall Benefit of Analgesia Score daily until discharge. RESULTS: Mean age was 57 ± 14 years, 43% of patients were female, and mean BMI was 28.6 ± 6 kg/m2. The 2 groups were similar in demographic characteristics and distribution of diagnoses and procedures. Epidural analgesia had a higher incidence of hypotensive systolic blood pressure (<90 mmHg) episodes (9 vs 2; p < 0.05) and a trend toward longer Foley catheter duration (3 ± 2 days vs 2 ± 4 days; p > 0.05). Epidural and IA had equivalent mean lengths of stay (4 ± 3 days vs 4 ± 3 days), daily Visual Analogue Scale scores (2.4 ± 2.0 vs 3.0 ± 2.0), and Overall Benefit of Analgesia Scores (3.2 ± 2.0 vs 3.2 ± 2.0), and similar time to start oral diet (2.8 ± 2 days vs 2.2 ± 1 days). Epidural analgesia patients used a higher total dose of narcotics (147.5 ± 192.0 mg vs 98.1 ± 112.0 mg; p > 0.05). Epidural and IV analgesia had equivalent total hospital charges ($144,991 ± $67,636 vs $141,339 ± $75,579; p > 0.05). CONCLUSIONS: This study indicates that EA has no added clinical benefit in patients undergoing minimally invasive colorectal surgery. A trend toward higher total narcotics use and complications with EA was demonstrated.

Lymph Node Positivity in Appendiceal Adenocarcinoma: Should Size Matter?

BACKGROUND: The management algorithm for appendiceal adenocarcinoma is not well defined. This study sought to determine whether tumor size or depth of invasion better correlates with the presence of lymph node metastases in appendiceal adenocarcinoma, and to compare these rates with colon adenocarcinoma. STUDY DESIGN: A retrospective review of the National Cancer Database was performed to identify patients with appendiceal or colonic adenocarcinoma from 2004 to 2013 who underwent surgical resection. Cases were categorized by tumor size and by T stage. Rates of lymph node metastases were examined as a function of size and T stage. RESULTS: A total of 3,402 appendiceal and 314,864 colonic cases were identified. For appendiceal adenocarcinoma, larger tumor size was associated with higher T stage: Pearson correlation of 0.41 (95% CI 0.408 to 0.414; p < 0.001). Lymph node metastases were present in 19.1%, 27.8%, 39.6%, 39.4%, 42.4% and 39.1% for tumor sizes <1 cm, >1 to 2 cm, >2 to 3 cm, >3 to 4 cm, >4 to 5 cm, and >5 cm, respectively. Lymph node metastases were present in 0%, 11.2%, 12.3%, 35.5%, and 40.0% for in situ, T1, T2, T3, and T4 tumors, respectively. There was no difference in the rates of lymph node metastases between appendiceal and colonic adenocarcinoma for tumor sizes <3 cm, or for in situ and T1 tumors. Rates of lymph node metastases are higher in colonic adenocarcinoma for tumor sizes >3 cm and for T2, T3, and T4 tumors (p < 0.01). CONCLUSIONS: In appendiceal adenocarcinoma, the rate of lymph node metastases is substantial, even for small tumors. Tumor size should play no role in the decision of whether to perform a hemicolectomy. Appendectomy alone does not produce an adequate lymph node sample. Right hemicolectomy should be performed for all appendiceal adenocarcinomas.

Cerebrovascular pathology in Down syndrome and Alzheimer disease.

People with Down syndrome (DS) are at high risk for developing Alzheimer disease (AD) with age. Typically, by age 40 years, most people with DS have sufficient neuropathology for an AD diagnosis. Interestingly, atherosclerosis and hypertension are atypical in DS with age, suggesting the lack of these vascular risk factors may be associated with reduced cerebrovascular pathology. However, because the extra copy of APP leads to increased beta-amyloid peptide (Aß) accumulation in DS, we hypothesized that there would be more extensive and widespread cerebral amyloid angiopathy (CAA) with age in DS relative to sporadic AD. To test this hypothesis CAA, atherosclerosis and arteriolosclerosis were used as measures of cerebrovascular pathology and compared in post mortem tissue from individuals with DS (n = 32), sporadic AD (n = 80) and controls (n = 37). CAA was observed with significantly higher frequencies in brains of individuals with DS compared to sporadic AD and controls. Atherosclerosis and arteriolosclerosis were rare in the cases with DS. CAA in DS may be a target for future interventional clinical trials.

Down Syndrome, Partial Trisomy 21, and Absence of Alzheimer's Disease: The Role of APP.

Overexpression of the amyloid precursor protein (APP) gene on chromosome 21 in Down syndrome (DS) has been linked to increased brain amyloid levels and early-onset Alzheimer's disease (AD). An elderly man with phenotypic DS and partial trisomy of chromosome 21 (PT21) lacked triplication of APP affording an opportunity to study the role of this gene in the pathogenesis of dementia. Multidisciplinary studies between ages 66-72 years comprised neuropsychological testing, independent neurological exams, amyloid PET imaging with 11C-Pittsburgh compound-B (PiB), plasma amyloid-ß (Aß) measurements, and a brain autopsy examination. The clinical phenotype was typical for DS and his intellectual disability was mild in severity. His serial neuropsychological test scores showed less than a 3% decline as compared to high functioning individuals with DS who developed dementia wherein the scores declined 17-28% per year. No dementia was detected on neurological examinations. On PiB-PET scans, the patient with PT21 had lower PiB standard uptake values than controls with typical DS or sporadic AD. Plasma Aß42 was lower than values for demented or non-demented adults with DS. Neuropathological findings showed only a single neuritic plaque and neurofibrillary degeneration consistent with normal aging but not AD. Taken together the findings in this rare patient with PT21 confirm the obligatory role of APP in the clinical, biochemical, and neuropathological findings of AD in DS.

A Decade Analysis of Trends and Outcomes of Male vs Female Patients Who Underwent Bariatric Surgery.

BACKGROUND: Male obesity rates are now estimated to be equal to female obesity rates. Despite this, men constitute a minority of patients undergoing bariatric surgery. The aim of this study was to examine the national trends and outcomes of bariatric surgery in male patients compared with female patients. STUDY DESIGN: The Nationwide Inpatient Sample database was reviewed for obese patients undergoing bariatric surgery between 2002 and 2011. Outcomes were analyzed according to sex. Main outcomes measures were patient demographics, length of stay, risk-adjusted inpatient morbidity and mortality, and hospital charge. RESULTS: During the 10-year period, 810,999 patients underwent bariatric surgery; 19.3% were male and 80.7% were female. The percentage of male patients increased from 15.4% in 2002 to 21.7% in 2011. Mean age was significantly older for males (46 ± 11 years vs 43 ± 11 years; p < 0.01, respectively). Male patients had a higher proportion of moderate, major, and extreme severity of illness classifications and higher rates of comorbid conditions. Serious morbidity was significantly higher in male patients compared with female patients (7.58% vs 5.42%; p < 0.01). Mean hospital length of stay was longer for male patients (2.75 vs 2.61 days; p < 0.01) with a higher mean hospital charge ($38,682 vs $34,294; p < 0.01). Compared with the female group, the male group had higher risk-adjusted in-hospital mortality (odds ratio = 2.16; 95% CI, 1.62-2.88; p < 0.01) and serious morbidity (odds ratio = 1.23; 95% CI, 1.17-1.29; p < 0.01). CONCLUSIONS: The number of male patients undergoing bariatric surgery in the past decade continues to be a small fraction compared with the number of female patients. Men undergoing bariatric surgery tend to have higher severity of illness, with higher risk-adjusted serious morbidity and mortality rates. Additional studies are necessary to examine barriers in obtaining treatment for obese men.

Effect of Resident Involvement on Patient Outcomes in Complex Laparoscopic Gastrointestinal Operations.

BACKGROUND: Multiple studies examining the impact of resident involvement on patient outcomes in general surgical operations have shown an associated increase in morbidity and operative time. However, these studies included basic and advanced laparoscopic and open operations. The aim of this study was to examine the impact of resident involvement on outcomes specifically in patients who underwent complex minimally invasive gastrointestinal operations. STUDY DESIGN: The American College of Surgeons NSQIP database was reviewed for patients who underwent laparoscopic colectomy and laparoscopic paraesophageal hernia and anti-reflux procedures between 2002 and 2010. Data were analyzed based on operations performed with a resident involved compared with those performed by an attending surgeon without resident involvement. Primary end points included risk-adjusted 30-day mortality, 30-day reoperation, and 30-day serious morbidity. Secondary end points were operative time, hospital length of stay, and 30-day overall morbidity. RESULTS: A total of 31,736 cases were analyzed; 63.3% of cases had a resident involved in the operation and 36.7% were performed by an attending without resident involvement. Operative time was significantly longer in cases performed with a resident (162 vs 138 minutes in attending-only cases; p < 0.01), however, there were no significant differences between groups with regard to hospital length of stay (4.5 vs 4.5 days, respectively). Compared with cases without resident involvement, risk-adjusted outcomes for cases with resident involvement showed no significant differences in 30-day serious morbidity (odds ratio = 1.03; 95% CI, 0.94-1.14; p = 1.0), 30-day mortality (odds ratio = 0.83; 95% CI, 0.60-1.15; p = 1.0), or 30-day reoperation (odds ratio = 0.93; 95% CI, 0.81-1.06; p = 1.0). CONCLUSIONS: Resident involvement in complex laparoscopic gastrointestinal procedures is associated with an increase in operative time with no impact on postoperative outcomes.

Analysis of Endoscopic Retrograde Cholangiopancreatography after Positive Intraoperative Cholangiogram: Is It Necessary?

The necessity of routine endoscopic retrograde cholangiopancreatography (ERCP) after positive intraoperative cholangiogram (IOC) during laparoscopic cholecystectomy is not well defined. We aimed to examine the incidence of positive IOC among patients who undergo IOC during cholecystectomy and the rate of subsequent ERCP stone extraction. The Nationwide Inpatient Sample database was reviewed for all patients undergoing cholecystectomy with IOC from 2002 to 2012. Patients were then analyzed for ERCP and stone extraction. A total of 73,508 patients who underwent cholecystectomy with IOC for a diagnosis of acute cholecystitis and found to have a bile duct stone were identified. Of these patients, 5915 underwent subsequent ERCP. In the patients that underwent subsequent ERCP, 1478 had a documented stone extraction during ERCP. The rate of stone extraction in the ERCP subset is 25 per cent, which is 2 per cent of all patients who had a positive IOC. The rate of stone extraction after positive IOC is low. Positive IOC may not warrant a routine postoperative ERCP. Our results suggest that clinical monitoring of patients with positive IOC is reasonable, as the majority of patients with a positive IOC ultimately have no stone extraction.