Nonsurgical Comparison Group Research Articles

Long-term cancer outcomes after bariatric surgery.

Obesity is associated with increased cancer risk. Because of the substantial and sustained weight loss following bariatric surgery, postsurgical patients are ideal to study the association of weight loss and cancer. Retrospectively (1982-2019), 21,837 bariatric surgery patients (surgery, 1982-2018) were matched 1:1 by age, sex, and BMI with a nonsurgical comparison group. Procedures included gastric bypass, gastric banding, sleeve gastrectomy, and duodenal switch. Primary outcomes included cancer incidence and mortality, stratified by obesity- and non-obesity-related cancers, sex, cancer stage, and procedure. Bariatric surgery patients had a 25% lower risk of developing any cancers compared with a nonsurgical comparison group(hazard ratio [HR] 0.75; 95% CI 0.69-0.81; p < 0.001). Cancer incidence was lower among female (HR 0.67; 95% CI 0.62-0.74; p < 0.001) but not male surgery patients, with the HR lower for females than for males (p < 0.001). Female surgerypatients had a 41% lower risk for obesity-related cancers (i.e., breast, ovarian, uterine, and colon) compared with nonsurgical females (HR 0.59; 95% CI 0.52-0.66; p < 0.001). Cancer mortality was significantly lower after surgery in females (HR 0.53; 95% CI 0.44-0.64; p < 0.001). Bariatric surgery was associated with lower all-cancer and obesity-related cancer incidence among female patients. Cancer mortality was significantly lower among females in thesurgical group versus the nonsurgical group.

Gut microbiota differs a decade after bariatric surgery relative to a nonsurgical comparison group.

Few studies have assessed differences in the gut microbiota composition after bariatric surgery in the long term or whether differences are correlated with remission of type 2 diabetes. This observational study assessed differences in the gut microbiota between individuals at up to 13 years after surgery and a comparison group of individuals with severe obesity. The relationship between type 2 diabetes remission and the gut microbiota was also assessed. University. Stool samples were collected from individuals completing bariatric surgery (surgery group; n = 16) and individuals with severe obesity that did not receive surgery (nonsurgery group; n = 19) as part of the 12-year follow-up in the Utah Obesity Study. Metabolic health data were collected at baseline and the follow-up examination. The gut microbiota was quantified by sequencing the V4 region of the 16 S rRNA gene. Significant differences in microbiota composition with surgery and other covariates were determined by Unifrac distance analysis and permutational multivariate analysis of variance. Significant differences in the relative abundance of individual bacterial taxa were assessed using analysis of composition of microbiomes software. The surgery group had higher relative abundances of Verrucomicrobiaceae (5.7 ± 1.3% versus 1.1 ± .3%) and Streptococcaceae (6.3 ± 1.0% versus 3.2 ± .8%), but lower relative abundances of Bacteroidaceae (8.8 ± 1.8% versus 18.6 ± 2.3%) 10.6 years after surgery. In a small subset of 8 individuals, a higher relative abundance of Akkermansia muciniphila was correlated with type 2 diabetes remission. Differences in the gut microbiota are evident a decade after bariatric surgery compared with individuals with severe obesity that did not undergo surgery. The observed long-term differences are consistent with previous findings.

Surgical treatment of pes planovalgus in ambulatory children with cerebral palsy: Static and dynamic changes as characterized by multi-segment foot modeling, physical examination and radiographs

BackgroundThis study employs multi-segment foot modeling (MSFM) to examine flatfoot reconstruction among ambulatory children with cerebral palsy (CP).Research Question: Does flatfoot reconstruction improve MSFM measures, physical examination and radiographic variables for forefoot varus and midfoot collapse and associated multi-planar compensatory features? MethodsMSFM was performed preoperatively and postoperatively in a cohort of ambulatory CP patients undergoing flatfoot reconstruction (surgical group, n = 24). A comparison group of non-surgical group of ambulatory CP patients with pes planovalgus (flatfoot) who did not undergo flatfoot reconstruction was also identified (n = 17). All patients in this comparison group underwent MSFM at two separate time points. Physical examination was performed and standing AP and lateral foot radiographs were obtained during each gait analysis session. ResultsPatients in the surgical group had improvement in their forefoot varus deformity, as documented on physical examination and kinematics in the STJN position of the foot and ankle, as well as in the compensatory hindfoot eversion and midfoot abduction during stance phase of gait. Furthermore, patients in the surgical group had improvement in midfoot collapse as identified kinematically by midfoot dorsiflexion, physical examination descriptors of midfoot position, and radiographic measures of calcaneal pitch and AP and lateral talar-first metatarsal angle. Patients in the non-surgical comparison group did not demonstrate these changes. SignificanceImprovements in foot motion after flatfoot reconstruction in ambulatory CP patients were identified by MSFM, physical examination measures, and radiographs. Patients in the surgical and non-surgical groups had similar pre-operative radiographic findings, suggesting that physical examination and MSFM data were important in the surgical decision making process. Finally, surgical intervention did not fully restore normal foot kinematic, physical examination, and radiographic parameters, which suggests that a different, perhaps more aggressive, surgical approach for flatfoot reconstruction is needed.

Sez6 levels are elevated in cerebrospinal fluid of patients with inflammatory pain-associated conditions.

Seizure-related protein 6 (Sez6) contributes to chronic pain development as sez6 knockout mice show attenuated pain behaviours after peripheral nerve injury, compared with control mice. The type I transmembrane isoform of Sez6 is cleaved by the β-amyloid precursor protein cleavage enzyme 1 (BACE1), resulting in Sez6 extracellular domain shedding from the neuron surface. To determine whether this BACE1-shed form of Sez6 can be detected in the cerebrospinal fluid (CSF) and whether Sez6 levels in the CSF are altered in neuropathic pain or chronic inflammatory pain (IP). We analysed the CSF samples collected during surgery from patients with chronic neuropathic pain (n = 8) or IP (n = 33), comparing them to the CSF samples from patients with suspected subarachnoid haemorrhage that was subsequently excluded (nonsurgical group, n = 5). Western blots were used to determine the relative Sez6 levels in the CSF from the different patient and nonsurgical comparison groups. The results show that BACE1-shed Sez6 can be readily detected in the CSF by Western blot and that the levels of Sez6 are significantly higher in the IP group than in the nonsurgical comparison group. The association between elevated Sez6 levels in the CSF and IP is further evidence for persistent alterations in central nervous system activity in chronic IP conditions.

Correction for retest effects across repeated measures of cognitive functioning: a longitudinal cohort study of postoperative delirium

BackgroundFew studies have compared methods to correct for retest effects or practice effects in settings where an acute event could influence test performance, such as major surgery. Our goal in this study was to evaluate the use of different methods to correct for the effects of practice or retest on repeated test administration in the context of an observational study of older adults undergoing elective surgery.MethodsIn a cohort of older surgical patients (N = 560) and a non-surgical comparison group (N = 118), we compared changes on repeated cognitive testing using a summary measure of general cognitive performance (GCP) between patients who developed post-operative delirium and those who did not. Surgical patients were evaluated pre-operatively and at 1, 2, 6, 12, and 18 months following surgery. Inferences from linear mixed effects models using four approaches were compared: 1) no retest correction, 2) mean-difference correction, 3) predicted-difference correction, and 4) model-based correction.ResultsUsing Approaches 1 or 4, which use uncorrected data, both surgical groups appeared to improve or remain stable after surgery. In contrast, Approaches 2 and 3, which dissociate retest and surgery effects by using retest-adjusted GCP scores, revealed an acute decline in performance in both surgical groups followed by a recovery to baseline. Relative differences between delirium groups were generally consistent across all approaches: the delirium group showed greater short- and longer-term decline compared to the group without delirium, although differences were attenuated after 2 months. Standard errors and model fit were also highly consistent across approaches.ConclusionAll four approaches would lead to nearly identical inferences regarding relative mean differences between groups experiencing a key post-operative outcome (delirium) but produced qualitatively different impressions of absolute performance differences following surgery. Each of the four retest correction approaches analyzed in this study has strengths and weakness that should be evaluated in the context of future studies. Retest correction is critical for interpretation of absolute cognitive performance measured over time and, consequently, for advancing our understanding of the effects of exposures such as surgery, hospitalization, acute illness, and delirium.

Factors associated with long-term weight-loss maintenance following bariatric surgery in adolescents with severe obesity.

Bariatric surgery produces robust weight loss, however, factors associated with long-term weight-loss maintenance among adolescents undergoing Roux-en-Y gastric bypass surgery are unknown. Fifty adolescents (mean±s.d. age and body mass index (BMI)=17.1±1.7 years and 59±11 kg m-2) underwent Roux-en-Y gastric bypass surgery, had follow-up visits at 1 year and at a visit between 5 and 12 years following surgery (Follow-up of Adolescent Bariatric Surgery at 5 Plus years (FABS-5+) visit; mean±s.d. 8.1±1.6 years). A non-surgical comparison group (n=30; mean±s.d. age and BMI=15.3±1.7 years and BMI=52±8 kg m-2) was recruited to compare weight trajectories over time. Questionnaires (health-related and eating behaviors, health responsibility, impact of weight on quality of life (QOL), international physical activity questionnaire and dietary habits via surgery guidelines) were administered at the FABS-5+ visit. Post hoc, participants were split into two groups: long-term weight-loss maintainers (n=23; baseline BMI=58.2 kg m-2; 1-year BMI=35.8 kg m-2; FABS-5+ BMI=34.9 kg m-2) and re-gainers (n=27; baseline BMI=59.8 kg m-2; 1-year BMI=36.8 kg m-2; FABS-5+ BMI=48.0 kg m-2) to compare factors which might contribute to differences. Data were analyzed using generalized estimating equations adjusted for age, sex, baseline BMI, baseline diabetes status and length of follow-up. The BMI of the surgical group declined from baseline to 1 year (-38.5±6.9%), which, despite some regain, was largely maintained until FABS-5+ (-29.6±13.9% change). The BMI of the comparison group increased from baseline to the FABS-5+ visit (+10.3±20.6%). When the surgical group was split into maintainers and re-gainers, no differences in weight-related and eating behaviors, health responsibility, physical activity/inactivity, or dietary habits were observed between groups. However, at FABS-5+, maintainers had greater overall QOL scores than re-gainers (87.5±10.5 vs 65.4±20.2, P<0.001) and in each QOL sub-domain (P<0.01 all). Long-term weight outcomes for those who underwent weight-loss surgery were superior to those who did not undergo surgical treatment. While no behavioral factors were identified as predictors of success in long-term weight-loss maintenance, greater QOL was strongly associated with maintenance of weight loss among adolescents who underwent Roux-en-Y gastric bypass surgery surgery.

Long-term impact of childhood selective dorsal rhizotomy on pain, fatigue, and function: a case-control study.

Selective dorsal rhizotomy (SDR) is a surgical treatment for spasticity in children with cerebral palsy (CP). Studies suggest long-lasting effects of SDR on spasticity; long-term effects on symptoms and function are not clear. This study tested whether adults with CP (average 22y after SDR) report less pain, fatigue, and functional decline than a retrospectively assessed non-surgical comparison group. This was a case-control study. Eighty-eight adults with CP (mean age 27y; SDR=38 male/female/missing=20/16/2; non-surgical [comparison]=50, male/female=19/31) recruited from a tertiary care center and the community completed a battery of self-reported outcome measures. Regression models were used to test whether SDR status predicted pain, fatigue, functional change, and hours of assistance (controlling for Gross Motor Function Classification System level). SDR status did not significantly predict pain interference (p=0.965), pain intensity (p=0.512), or fatigue (p=0.404). SDR related to lower decline in gross motor functioning (p=0.010) and approximately 6 fewer hours of daily assistance than for those in the comparison group (p=0.001). Adults with CP who had SDR in childhood reported less gross motor decline and fewer daily assistance needs than non-surgically treated peers, suggesting the functional impact of SDR persists long after surgery.

Verbal Fluency in Parkinson's Patients with and without Bilateral Deep Brain Stimulation of the Subthalamic Nucleus: A Meta-analysis.

Patients with Parkinson's disease often experience significant decline in verbal fluency over time; however, deep brain stimulation of the subthalamic nucleus (STN-DBS) is also associated with post-surgical declines in verbal fluency. The purpose of this study was to determine if Parkinson's patients who have undergone bilateral STN-DBS have greater impairment in verbal fluency compared to Parkinson's patients treated by medication only. A literature search yielded over 140 articles and 10 articles met inclusion criteria. A total of 439 patients with Parkinson's disease who underwent bilateral STN-DBS and 392 non-surgical patients were included. Cohen's d, a measure of effect size, was calculated using a random effects model to compare post-treatment verbal fluency in patients with Parkinson's disease who underwent STN-DBS versus those in the non-surgical comparison group. The random effects model demonstrated a medium effect size for letter fluency (d=-0.47) and a small effect size for category fluency (d=-0.31), indicating individuals with bilateral STN-DBS had significantly worse verbal fluency performance than the non-surgical comparison group. Individuals with Parkinson's disease who have undergone bilateral STN-DBS experience greater deficits in letter and category verbal fluency compared to a non-surgical group.

Long-term health-related quality of life in bariatric surgery patients: A systematic review and meta-analysis.

Bariatric surgery results in significant weight loss in the majority of patients. Improvement in health-related quality of life (HRQoL) is an equally important outcome; however, there are few studies reporting long-term (≥5 years) HRQoL outcomes. This study assesses the quality of evidence and effectiveness of surgery on HRQoL ≥ 5 years. PubMed, Cochrane Review, EmBase, CINANL, PsycInfo, obesity conference abstracts, and reference lists were searched. Keywords were bariatric surgery, obesity, and quality of life. Studies were included if (1) there was ≥5 years follow-up, (2) patients had class II or III obesity, (3) individuals completed a validated HRQoL survey, and (4) there was a nonsurgical comparison group with obesity. Two reviewers independently assessed each study. From 1376 articles, 9 studies were included in the systematic review (SR) and 6 in the meta-analysis (MA). Inconsistent results for long-term improvements in physical and mental health emerged from the SR. In contrast, the MA found significant improvements in these domains ≥5 years after surgery. Study findings provide evidence for a substantial and significant improvement in physical and mental health favoring the surgical group compared with controls spanning 5 to 25 years after surgery.

Abstract 14888: Lipid Changes 8 Years Post Gastric Bypass in Adolescents With Severe Obesity

Introduction: Severe obesity in adolescents is increasing and few effective treatments exist. Weight loss surgery is one option, but the extent to which surgery influences cardiovascular risk factors such as lipids in youth is not clear. We studied the impact of weight loss surgery in adolescents with severe obesity on lipid parameters in the Follow-up of Adolescent Bariatric Surgery-5+ (FABS-5+) study &gt;5 years postoperatively. Hypothesis: We predicted weight loss surgery would be associated with a greater improvement in lipids compared to no surgery. Methods: Adolescents and young adults who either underwent laparoscopic Roux-en Y gastric bypass (RYGB; “Surgical”) or who were seeking weight loss treatment (“Non-Surgical”) in 2001-2007 were recruited for the FABS-5+ follow-up study between 2011-2013. Baseline (pre-treatment) BMI and fasting lipids and TG/HDL-C ratio (representing small dense LDL particles) were abstracted from charts. Follow-up data were obtained at a research visit. Changes in BMI and lipids were evaluated using paired t-tests and Wilcoxon signed rank tests. Results: At baseline, surgical participants (n=58; 80% of all RYGB cases performed in 2001-2007) were a mean±SD age of 17±2 years and 25±2 at follow-up. 86% were Caucasian and 64% were female. After RYGB, BMI was 29% lower than baseline (p&lt;0.01). All lipids (except total cholesterol) significantly improved with the largest changes in HDL-C and TG/HDL-C ratio. In the non-surgical comparison group (n=30) from baseline to follow up (ages 15±2 and 22±2 years, respectively), BMI increased by 8% but lipid parameters were similar (Table). Conclusions: This is the longest term and most complete follow-up of youth following RYGB. Weight loss was durably maintained and significant improvements in lipid profile were observed. Whether these lipid improvements translate into reductions in atherosclerosis and cardiovascular events overtime remains to be determined.

Evaluation of behavioral outcomes in children 1 year after epilepsy surgery.

Children with epilepsy have elevated rates of behavior problems. Research findings on the impact of epilepsy surgery on children's behavior have been mixed, with some studies showing improvements in behavior 3 to 18months after surgery and other studies finding no change within this time interval. We examined behavior in a large surgical sample and in a nonsurgical comparison group. We also examined for potential effects of epilepsy-related and cognitive/linguistic variables. Behavior was assessed by parent report in 147 children who underwent epilepsy surgery and 40 children who did not, using the Child Behavior Checklist (CBCL). For the surgical group, the CBCL was completed prior to surgery (baseline) and approximately 1year after surgery (follow-up); ratings of the nonsurgical group were also conducted twice, at comparable intervals. At baseline, the groups did not differ on age, sex, age at seizure onset, antiepileptic drugs (AEDs), or intelligence quotient (IQ). Baseline Social and Attention Problems were higher in the nonsurgical group. At follow-up, 65% of the surgical group and 20% of the nonsurgical group were seizure-free. Behavioral change was not related to surgical status or seizure outcome. Children with temporal lobe seizure focus had more Externalizing Behaviors compared to those with frontal or multilobar foci. Attention was poorer in children who underwent frontal lobe excisions relative to temporal or multilobar excisions. Baseline IQ did not predict behavioral change. Our results suggest that surgery and seizure outcome do not affect behavior in the first year following surgery; it may be the abnormal neural substrate and not seizure control that influences behavior in children with epilepsy. If changes are to occur due to seizure freedom, they may require a longer time to emerge. Some behaviors may be resistant to change in children with epilepsy or may require even longer intervals for improvement.

Quality of life in young adults who underwent resective surgery for epilepsy in childhood

This study investigated quality of life (QOL) in young adults who had undergone epilepsy surgery before the age of 16 years. The contribution to QOL of seizure status in the prior year, sex, number of antiepileptic drugs, and mood were evaluated. Sixty-nine young adults who had undergone surgery were subdivided into those who were seizure-free in the past year (n = 38) and those who had seizures (n = 31) in that time. A nonsurgical comparison group of young adults (n = 29) with childhood-onset medically intractable epilepsy was also studied. All groups completed measures of QOL and mood. After accounting for mood, sex, and number of antiepileptic drugs, the seizure-free group reported better cognitive and physical function and overall QOL, experienced less seizure worry, and had better self-perception. Mood was the most consistently predictive covariate, and was independently predictive of many aspects of QOL. Seizure freedom associated with surgery in childhood is associated with improved QOL in certain domains. Findings highlight the importance of mood in determining self-perception of QOL.

Long-term intellectual outcome after temporal lobe surgery in childhood

Temporal lobe resection is an established treatment for medication-resistant temporal lobe epilepsy, which in recent years has increasingly been performed in children. However, little is known about the long-term outcome in these children. The aim of this study was to characterize intellectual and psychosocial functioning of children after temporal lobe resection as they progress into late adolescence and adulthood. We report the long-term follow-up of 42 children who underwent temporal lobe surgery after an average postoperative period of 9 years. Longitudinal change in IQ was documented, psychosocial outcome including quality of life was assessed, and preoperative and postoperative T1-weighted MRI brain scans were evaluated quantitatively. A well-matched nonsurgical comparison group of 11 children with similar clinical characteristics was also assessed. At follow-up, 86% of the surgical group were seizure-free, and 57% were no longer taking antiepileptic medication. A significant increase in IQ was found in the surgical group after an extended follow-up period of >5 years. This IQ change was not found in the nonsurgical comparison group. IQ increases were associated with cessation of antiepileptic medication and changes in MRI-derived gray matter volume. The surgical group also reported better psychosocial outcome including quality of life, which was more strongly associated with seizure freedom rather than surgery per se. Surgery for temporal lobe epilepsy performed in childhood results in excellent long-term seizure control and favorable cognitive outcome along with positive effects on brain development. This study provides Class III evidence that temporal lobectomy in children with temporal lobe epilepsy is associated with improved long-term intellectual outcomes compared with those undergoing standard medical treatment.

Absence of Cognitive Decline One Year After Coronary Bypass Surgery: Comparison to Nonsurgical and Healthy Controls

Cognitive decline after open-heart surgery has been the subject of a number of conflicting reports in recent years. Determination of possible cognitive impairment due to surgery or use of cardiopulmonary bypass is complicated by numerous factors, including use of appropriate comparison groups and consideration of practice effects in cognitive testing. Neuropsychological data were gathered from 46 healthy controls, 42 cardiac patients referred for percutaneous coronary intervention (PCI), and 43 cardiac patients referred for coronary artery bypass grafting (CABG). Fourteen cognitive function tests were utilized at baseline and at three time points after surgery (3 weeks, 4 months, 1 year). Measures showing acceptable test-retest reliability based on intraclass correlations were compared using regression-based reliable change indices. No clear pattern of group differences or change at follow-up emerged. A greater percentage of CABG patients than controls worsened in seven tests (three at 1 year), but a greater percentage of PCI patients than controls also worsened in seven tests (three at 1 year). Generalized estimating equations showed only two tests (Wechsler Adult Intelligence Scale, Third Edition, Digit Symbol, and Hopkins Verbal Learning Test, Revised, Total Recall) to be significantly different between groups from baseline to 1 year. Interestingly, compared with healthy controls, more PCI patients than CABG patients worsened in the former of those two tests, whereas more PCI and CABG patients improved on the latter. Using healthy controls and a relevant nonsurgical comparison group to contend with important methodological considerations, current CABG procedure does not appear to create cognitive decline.

Temporal lobe epilepsy, temporal lobectomy, and major depression.

Sixty-two patients with medically intractable complex partial seizures who had either surgical or no surgical intervention were followed up at a mean of 10.9 years after surgery or initial evaluation. Of the 49 surgical patients, 45% had a life-time history of depression, versus 15% of the 13 patients in the nonsurgical comparison group. In the surgical group, 77% had prior history of depression; of these, 47% experienced no further episodes after surgery. Depression occurred de novo after lobectomy in 5 surgical patients (approximately 10%), 4 developing depression within 1 year. Presurgical presence of depressive episodes predicted continued postoperative depressive episodes. The significantly higher depression rate in patients with temporal lobe seizure foci suggests limbic system dysfunction in the increased risk for depression. Postsurgical resolution of episodes in almost 50% of these patients supports the tenet that depression per se is not a contraindication for surgery in patients with intractable seizures.