Bariatric surgery results in reduced muscle mass as weight is lost, but postoperative changes in muscle strength and performance are incompletely understood.
To examine changes in body composition, ...strength, physical activity, and physical performance following Roux-en-Y gastric bypass (RYGB).
In a prospective cohort of 47 adults (37 women, 10 men) aged 45 ± 12 years (mean ± SD) with body mass index (BMI) 44 ± 8 kg/m2, we measured body composition by dual-energy X-ray absorptiometry, handgrip strength, physical activity, and physical performance (chair stand time, gait speed, 400-m walk time) before and 6 and 12 months after RYGB. Relative strength was calculated as absolute handgrip strength/BMI and as absolute strength/appendicular lean mass (ALM).
Participants experienced substantial 12-month decreases in weight (-37 ± 10 kg or 30% ± 7%), fat mass (-48% ± 12%), and total lean mass (-13% ± 6%). Mean absolute strength declined by 9% ± 17% (P < 0.01). In contrast, relative strength increased by 32% ± 25% (strength/BMI) and 9% ± 20% (strength/ALM) (P < 0.01 for both). There were clinically significant postoperative improvements in all physical performance measures, including mean improvement in gait speed of >0.1 m/s (P < 0.01) and decrease in 400-m walk time of nearly a full minute.
In the setting of dramatic weight loss, lean mass and absolute grip strength declined after RYGB. However, relative muscle strength and physical function improved meaningfully and are thus noteworthy positive outcomes of gastric bypass.
Medulloblastoma is the most common malignant childhood brain tumor, although long-term risks for chronic neurologic health and psychosocial functioning in aging adult survivors are incompletely ...characterized.
The Childhood Cancer Survivor Study (CCSS) includes 380 five-year survivors of medulloblastoma/primitive neuroectodermal tumor (PNET; median age at follow-up: 30 y, interquartile range 24-36) and sibling comparison (n = 4031). Cumulative incidence of neurologic health conditions was reported. Cox regression models provided hazard ratios (HRs) and 95% CIs. Cross-sectional outcomes were assessed using generalized linear models.
Compared with siblings, survivors were at increased risk of late-onset hearing loss (HR: 36.0, 95% CI: 23.6-54.9), stroke (HR: 33.9, 95% CI: 17.8-64.7), seizure (HR: 12.8, 95% CI: 9.0-18.1), poor balance (HR: 10.4, 95% CI: 6.7-15.9), tinnitus (HR: 4.8, 95% CI: 3.5-6.8), and cataracts (HR: 31.8, 95% CI: 16.7-60.5). Temporal/frontal lobe radiotherapy of 50 Gy or more increased risk for hearing loss (HR: 1.9, 95% CI: 1.1-1.3), seizure (HR: 2.1, 95% CI: 1.1-3.9), stroke (HR: 3.5, 95% CI: 1.3-9.1), and tinnitus (HR: 2.0, 95% CI: 1.0-3.9). Survivors were less likely than siblings to earn a college degree (relative risk RR: 0.49, 95% CI: 0.39-0.60), marry (RR: 0.35, 95% CI: 0.29-0.42), and live independently (RR: 0.58, 95% CI: 0.52-0.66).
Adult survivors of childhood medulloblastoma/PNET demonstrate pronounced risk for hearing impairment, stroke, lower educational attainment, and social independence. Interventions to support survivors should be a high priority.
Laparoscopic sleeve gastrectomy (LSG), now the most commonly performed bariatric operation, is a highly effective treatment for obesity. While Roux-en-Y gastric bypass is known to impair intestinal ...fractional calcium absorption (FCA) and negatively affect bone metabolism, LSG's effects on calcium homeostasis and bone health have not been well characterized.
We determined the effect of LSG on FCA, while maintaining robust 25-hydroxyvitamin D (25OHD) levels and recommended calcium intake.
Prospective pre-post observational cohort study of 35 women and men with severe obesity undergoing LSG.
FCA was measured preoperatively and 6 months postoperatively with a gold-standard dual stable isotope method. Other measures included calciotropic hormones, bone turnover markers, and bone mineral density (BMD) by dual-energy X-ray absorptiometry and quantitative computed tomography.
Mean ± SD FCA decreased from 31.4 ± 15.4% preoperatively to 16.1 ± 12.3% postoperatively (P < 0.01), while median (interquartile range) 25OHD levels were 39 (32-46) ng/mL and 36 (30-46) ng/mL, respectively. Concurrently, median 1,25-dihydroxyvitamin D level increased from 60 (50-82) pg/mL to 86 (72-107) pg/mL (P < 0.01), without significant changes in parathyroid hormone or 24-hour urinary calcium levels. Bone turnover marker levels increased substantially, and areal BMD decreased at the proximal femur. Those with lower postoperative FCA had greater areal BMD loss at the total hip (ρ = 0.45, P < 0.01).
FCA decreases after LSG, with a concurrent rise in bone turnover marker levels and decline in BMD, despite robust 25OHD levels and with recommended calcium intake. Decline in FCA could contribute to negative skeletal effects following LSG.
Laparoscopic sleeve gastrectomy (LSG), the most common bariatric surgical procedure, leads to durable weight loss and improves obesity-related comorbidities. However, it induces abnormalities in bone ...metabolism. One unexplored potential contributor is the gut microbiome, which influences bone metabolism and is altered after surgery. We characterized the relationship between the gut microbiome and skeletal health in severe obesity and after LSG. In a prospective cohort study, 23 adults with severe obesity underwent skeletal health assessment and stool collection preoperatively and 6 mo after LSG. Gut microbial diversity and composition were characterized using 16S rRNA gene sequencing, and fecal concentrations of short-chain fatty acids (SCFA) were measured with LC-MS/MS. Spearman's correlations and PERMANOVA analyses were applied to assess relationships between the gut microbiome and bone health measures including serum bone turnover markers (C-terminal telopeptide of type 1 collagen CTx and procollagen type 1 N-terminal propeptide P1NP), areal BMD, intestinal calcium absorption, and calciotropic hormones. Six months after LSG, CTx and P1NP increased (by median 188% and 61%, P < .01) and femoral neck BMD decreased (mean -3.3%, P < .01). Concurrently, there was a decrease in relative abundance of the phylum Firmicutes. Although there were no change in overall microbial diversity or fecal SCFA concentrations after LSG, those with greater within-subject change in gut community microbial composition (β-diversity) postoperatively had greater increases in P1NP level (ρ = 0.48, P = .02) and greater bone loss at the femoral neck (ρ = -0.43, P = .04). In addition, within-participant shifts in microbial richness/evenness (α-diversity) were associated with changes in IGF-1 levels (ρ = 0.56, P < .01). The lower the postoperative fecal butyrate concentration, the lower the IGF-1 level (ρ = 0.43, P = .04). Meanwhile, the larger the decrease in butyrate concentration, the higher the postoperative CTx (ρ = -0.43, P = .04). These findings suggest that LSG-induced gut microbiome alteration may influence skeletal outcomes postoperatively, and microbial influences on butyrate formation and IGF-1 are possible mechanisms.
Abell 2146 (z = 0.232) consists of two galaxy clusters undergoing a major merger. The system was discovered in previous work, where two large shock fronts were detected using the Chandra X-ray ...Observatory, consistent with a merger close to the plane of the sky, caught soon after first core passage. A weak gravitational lensing analysis of the total gravitating mass in the system, using the distorted shapes of distant galaxies seen with Advanced Camera for Surveys - Wide Field Channel on Hubble Space Telescope, is presented. The highest peak in the reconstruction of the projected mass is centred on the brightest cluster galaxy (BCG) in Abell 2146-A. The mass associated with Abell 2146-B is more extended. Bootstrapped noise mass reconstructions show the mass peak in Abell 2146-A to be consistently centred on the BCG. Previous work showed that BCG-A appears to lag behind an X-ray cool core; although the peak of the mass reconstruction is centred on the BCG, it is also consistent with the X-ray peak given the resolution of the weak lensing mass map. The best-fitting mass model with two components centred on the BCGs yields M
200 = 1.1
$^{+0.3}_{-0.4}$
× 1015 and 3
$^{+1}_{-2}$
× 1014 M⊙ for Abell 2146-A and Abell 2146-B, respectively, assuming a mass concentration parameter of c = 3.5 for each cluster. From the weak lensing analysis, Abell 2146-A is the primary halo component, and the origin of the apparent discrepancy with the X-ray analysis where Abell 2146-B is the primary halo is being assessed using simulations of the merger.
•Gut hormone and bone changes were assessed 6 months after gastric bypass surgery.•Peptide YY changes negatively correlated with BMD and bone formation marker changes.•Uncoupling of bone turnover ...correlated with spine BMD loss.
The gut hormones peptide YY (PYY) and ghrelin mediate in part the metabolic benefits of Roux-en-Y gastric bypass (RYGB) surgery. However, preclinical data suggest these hormones also affect the skeleton and could contribute to postoperative bone loss.
We investigated whether changes in fasting serum total PYY and ghrelin were associated with bone turnover marker levels and loss of bone mineral density (BMD) after RYGB.
Prospective cohort of adults undergoing RYGB (n=44) at San Francisco academic hospitals.
We analyzed 6-month changes in PYY, ghrelin, bone turnover markers, and BMD by dual-energy x-ray absorptiometry (DXA) and quantitative computed tomography (QCT). We calculated the uncoupling index (UI), reflecting the relative balance of bone resorption and formation.
Postoperatively, there was a trend for an increase in PYY (+25pg/mL, p=0.07) and a significant increase in ghrelin (+192pg/mL, p<0.01). PYY changes negatively correlated with changes in spine BMD by QCT (r=-0.36, p=0.02) and bone formation marker P1NP (r=-0.30, p=0.05). Relationships were significant after adjustments for age, sex, and weight loss. No consistent relationships were found between ghrelin and skeletal outcomes. Mean 6-month UI was -3.3; UI correlated with spine BMD loss by QCT (r=0.40, p=0.01).
Postoperative PYY increases were associated with attenuated increases in P1NP and greater declines in spine BMD by QCT. Uncoupling of bone turnover correlated with BMD loss. These findings suggest a role for PYY in loss of bone mass after RYGB and highlight the relationship between intestinal and skeletal metabolism.
The adverse skeletal effects of Roux-en-Y gastric bypass (RYGB) are partly caused by intestinal calcium absorption decline. Prebiotics, such as soluble corn fiber (SCF), augment colonic calcium ...absorption in healthy individuals.
We tested the effects of SCF on fractional calcium absorption (FCA), biochemical parameters, and the fecal microbiome in a post-RYGB population.
Randomized, double-blind, placebo-controlled trial of 20 postmenopausal women with history of RYGB a mean 5 years prior; a 2-month course of 20 g/day SCF or maltodextrin placebo was taken orally. The main outcome measure was between-group difference in absolute change in FCA (primary outcome) and was measured with a gold standard dual stable isotope method. Other measures included tolerability, adherence, serum calciotropic hormones and bone turnover markers, and fecal microbial composition via 16S rRNA gene sequencing.
Mean FCA ± SD at baseline was low at 5.5 ± 5.1%. Comparing SCF to placebo, there was no between-group difference in mean (95% CI) change in FCA (+3.4 -6.7, +13.6%), nor in calciotropic hormones or bone turnover markers. The SCF group had a wider variation in FCA change than placebo (SD 13.4% vs 7.0%). Those with greater change in microbial composition following SCF treatment had greater increase in FCA (r2 = 0.72, P = 0.05). SCF adherence was high, and gastrointestinal symptoms were similar between groups.
No between-group differences were observed in changes in FCA or calciotropic hormones, but wide CIs suggest a variable impact of SCF that may be due to the degree of gut microbiome alteration. Daily SCF consumption was well tolerated. Larger and longer-term studies are warranted.
Survivors of childhood central nervous system (CNS) tumors experience high rates of treatment-related neurologic sequelae. Whether survivors continue to be at increased risk for new events as they ...age is unknown.
Adverse neurologic health conditions in 5-year survivors of CNS tumors from the Childhood Cancer Survivor Study (n = 1876) were evaluated longitudinally at a median 23.0 years from diagnosis (range, 5.1-38.9), median age at last evaluation 30.3 years (range, 6.1-56.4). Multivariable regression estimated hazard ratios (HRs) and 95% CIs.
From 5 to 30 years post diagnosis, cumulative incidence increased for seizures from 27% to 41%, motor impairment 21% to 35%, and hearing loss 9% to 23%. Risks were elevated compared with siblings (eg, seizures HR: 12.7; 95% CI: 9.6-16.7; motor impairment HR: 7.6; 95% CI: 5.8-9.9; hearing loss HR: 18.4; 95% CI: 13.1-25.9). Regional brain doses of radiation therapy were associated with development of new deficits (eg, frontal ≥50 Gy and motor impairment HR: 2.0; 95% CI: 1.2-3.4). Increased risk for motor impairment was also associated with tumor recurrence (HR: 2.6; 95% CI: 1.8-3.8), development of a meningioma (HR: 2.3; 95% CI: 0.9-5.4), and stroke (HR: 14.9; 95% CI: 10.4-21.4). Seizure risk was doubled by recurrence (HR: 2.3; 95% CI: 1.6-3.2), meningioma (HR: 2.6; 95% CI: 1.1-6.5), and stroke (HR: 2.0; 95% CI: 1.1-3.4).
CNS tumor survivors remain at risk for new-onset adverse neurologic events across their lifespans at a rate greater than siblings. Cranial radiation, stroke, tumor recurrence, and development of meningioma were independently associated with late-onset adverse neurologic sequelae.
This mixed methods retrospective case series and qualitative descriptive study describes pregnancy outcomes during the postincarceration period. A retrospective case series via electronic medical ...record chart review from a subset of women attending a postincarceration primary care clinic with a condition of interest (pregnancy) described demographics, substance use, diagnoses, and pregnancy outcomes. We compared 27 pregnant to 79 nonpregnant women and contextualized quantitative data with qualitative descriptive vignettes. Twenty‐seven women completed 29 pregnancies (2 women with 2 deliveries each), all of which were unplanned; there were 11 live births, 8 pregnant at study closure, 7 miscarriages, and 3 terminations. Although substance use history was high, rates were higher among nonpregnant women (92% vs 74%). Among the 5 births, 4 tested positive for substance use during pregnancy. All 11 infants had pregnancy or delivery complications. Although 7 of the 10 pregnant women with live births had prior pregnancy complications, only 4 were placed in a special care obstetrics clinic. Although unplanned pregnancies were common, most births did not demonstrate maternal substance use. All live births had pregnancy or delivery complications, but few were accepted to specialist prenatal care, suggesting potential considerations for recently incarcerated women.