Association of brachial-ankle pulse wave velocity with cognitive impairment in peritoneal dialysis patients

BackgroundThe relationship between cognitive impairment (CI) and arterial stiffness in peritoneal dialysis (PD) patients has not been clearly clarified. The aim of this study was to examine the relationship between CI and arterial stiffness in PD patients.MethodsThis cross-sectional study enrolled PD patients who performed a vascular profiler test at a single PD center in China between January 2014 and June 2016. The cognitive function was evaluated using the Montreal cognitive assessment (MoCA). A noninvasive vascular screening device was used to assess arterial stiffness relevant indicators.ResultsA total of 643 PD patients with median age 45 (37–57.4) years and median duration of PD 27.8 (8.7–56.4) months were enrolled. The rate of CI was 49.9%. The mean brachial-ankle pulse wave velocity (baPWV) was 17.2 ± 5.6 m/s. Compared with normal cognitive function group, patients with CI had higher baPWV (18.6 ± 7.0 vs. 15.8 ± 3.2 m/s), systolic blood pressure (150.3 ± 21.5 vs. 144.2 ± 20.2 mmHg), and pulse pressure (59.7 ± 14.7 vs. 52.5 ± 11.6 mmHg), and lower ankle-brachial index (ABI, 1.12 ± 0.12 vs. 1.15 ± 0.09) (all p<.05). Compared with systolic blood pressure, pulse pressure, and ABI in receiver operating characteristic (ROC) analysis, baPWV had better performance in predicting CI (area under curve: 0.68, 95% confidence interval: 0.64–0.72). BaPWV was independently associated with MoCA score (B per SD, −0.42 [95% confidence interval, −0.71 to −0.12]; p = .006) and CI (OR per SD, 1.55 [95% confidence interval, 1.11–2.17]; p = .011) in PD patients after adjustment for confounders.ConclusionsHigher baPWV was independently associated with CI in PD patients.     

Longitudinal Changes of Cardiac Structure and Function in CKD (CASCADE Study)

Little is known regarding the natural longitudinal changes in cardiac structure and function in CKD. We hypothesized that baseline CKD stage is associated with progressive worsening in cardiac structure and function. We conducted a prospective longitudinal study, recruiting 300 patients with stages 3–5 CKD from a major regional tertiary center and university teaching hospital in Hong Kong. Baseline CKD stages were studied in relation to natural longitudinal changes in echocardiographic and tissue Doppler imaging–derived parameters. Over 1 year, the prevalence of left ventricular (LV) hypertrophy increased from 40.3% to 48.9%, median left atrial volume index increased 4.8 (interquartile range [IQR], 2.1, 7.7) ml/m² (P<0.001), peak systolic mitral annular velocity decreased 0.5 (IQR, −1.5, 0.5) cm/s (P<0.001), early diastolic mitral annular velocity decreased 0.5 (IQR, −1.5, 0.5) cm/s (P<0.001), and eGFR declined 2.0 (IQR, −5.0, 0.0) ml/min per 1.73 m². CKD stages 4 and 5 were associated with more baseline abnormalities in cardiac structure and function and predicted greater longitudinal progression in LV mass index (odds ratio [OR], 3.02; 95% confidence interval [95% CI], 1.39 to 6.58), volume index (OR, 2.58; 95% CI, 1.18 to 5.62), and left atrial volume index (OR, 2.61; 95% CI, 1.20 to 5.69) and worse diastolic dysfunction grade (OR, 3.17; 95% CI, 1.16 to 8.69) compared with stage 3a in the fully adjusted analysis. In conclusion, more advanced CKD at baseline may be associated with larger longitudinal increases in LV mass and volume and greater deterioration in diastolic function.     

Copeptin Is Associated with Kidney Length,Renal Function,and Prevalence of Simple Cysts in a Population-Based Study

Arginine vasopressin (AVP) has a key role in osmoregulation by facilitating water transport in the collecting duct. Recent evidence suggests that AVP may have additional effects on renal function and favor cyst growth in polycystic kidney disease. Whether AVP also affects kidney structure in the general population is unknown. We analyzed the association of copeptin, an established surrogate for AVP, with parameters of renal function and morphology in a multicentric population-based cohort. Participants from families of European ancestry were randomly selected in three Swiss cities. We used linear multilevel regression analysis to explore the association of copeptin with renal function parameters as well as kidney length and the presence of simple renal cysts assessed by ultrasound examination. Copeptin levels were log-transformed. The 529 women and 481 men had median copeptin levels of 3.0 and 5.2 pmol/L, respectively (P<0.001). In multivariable analyses, the copeptin level was associated inversely with eGFR (β=−2.1; 95% confidence interval [95% CI], −3.3 to −0.8; P=0.002) and kidney length (β=−1.2; 95% CI, −1.9 to −0.4; P=0.003) but positively with 24-hour urinary albumin excretion (β=0.11; 95% CI, 0.01 to 0.20; P=0.03) and urine osmolality (β=0.08; 95% CI, 0.05 to 0.10; P<0.001). A positive association was found between the copeptin level and the presence of renal cysts (odds ratio, 1.6; 95% CI, 1.1 to 2.4; P=0.02). These results suggest that AVP has a pleiotropic role in renal function and may favor the development of simple renal cysts.     

Proteinuria as a Noninvasive Marker for Renal Allograft Histology and Failure: An Observational Cohort Study

Proteinuria is routinely measured to assess renal allograft status, but the diagnostic and prognostic values of this measurement for renal transplant pathology and outcome remain unclear. We included 1518 renal allograft recipients in this prospective, observational cohort study. All renal allograft biopsy samples with concomitant data on 24-hour proteinuria were included in the analyses (n=2274). Patients were followed for ≥7 years post-transplantation. Compared with proteinuria <0.3 g/24 h, the hazard ratios for graft failure were 1.14 (95% confidence interval [95% CI], 0.81 to 1.60; P=0.50), for proteinuria 0.3–1.0 g/24 h, 2.17 (95% CI, 1.49 to 3.18; P<0.001), for proteinuria 1.0–3.0 g/24 h, and 3.01 (95% CI, 1.75 to 5.18; P<0.001), for proteinuria >3.0 g/24 h, independent of GFR and allograft histology. The predictive performance of proteinuria for graft failure was lower at 3 months after transplant (area under the receiver-operating characteristic curve [AUC] 0.64, P<0.001) than at 1, 2, and 5 years after transplant (AUC 0.73, 0.71, and 0.77, respectively, all P<0.001). Independent determinants of proteinuria were repeat transplantation, mean arterial pressure, transplant glomerulopathy, microcirculation inflammation, and de novo/recurrent glomerular disease. The discriminatory power of proteinuria for these intragraft injury processes was better in biopsy samples obtained >3 months after transplant (AUC 0.73, P<0.001) than in those obtained earlier (AUC 0.56, P<0.01), with 85% specificity but lower sensitivity (47.8%) for proteinuria >1.0 g/24 h. These data support current clinical guidelines to routinely measure proteinuria after transplant, but illustrate the need for more sensitive biomarkers of allograft injury and prognosis.     

Estimated glomerular filtration rate and urinary albumin excretion are independently associated with greater arterial stiffness: the Hoorn Study

Mild renal insufficiency is a risk factor for cardiovascular disease (CVD). Both a decline in GFR and (micro)albuminuria are associated with greater cardiovascular mortality. In ESRD, arterial stiffness, an important cause of CVD, is known to be greater, but few data exist in individuals with mild renal insufficiency or microalbuminuria. This study investigated the association of impaired renal function expressed as lower GFR or greater urinary albumin excretion with arterial stiffness. In a population-based study in 806 individuals (402 men), mean age 68 yr (range 50 to 87), peripheral arterial stiffness (by compliance and distensibility of the carotid, brachial, and femoral arteries and by the carotid elastic modulus [E(inc)]) and central arterial stiffness (by total systemic arterial compliance, carotid-femoral transit time, and aortic augmentation index) were measured ultrasonically. GFR was estimated (eGFR) by the Modification of Diet in Renal Disease (MDRD) formula. Urinary albumin excretion was expressed as urinary albumin/creatinine ratio (UACR). eGFR was 60.6 +/- 11.1 ml/min per 1.73 m(2). Median UACR was 0.57 mg/mmol (range 0.1 to 26.6). After adjustment for age, mean arterial pressure (MAP), gender, and glucose tolerance status (GTS), each 5-ml/min per 1.73 m(2) lower eGFR was associated with a lower distensibility coefficient of the carotid (regression coefficient beta -0.20 10(-3)/kPa; 95% confidence interval [CI] -0.34 to -0.07 10(-3)/kPa) and brachial artery (-0.15 10(-3)/kPa; 95% CI -0.28 to -0.03 10(-3)/kPa) and a greater carotid E(inc) (0.02 kPa; 95% CI 0.0004 to 0.04 kPa). No statistically significant association was found of eGFR with other arterial stiffness indices. After adjustment for age, MAP, gender, and GTS, a greater UACR (per quartile) was associated with a greater E(inc) (0.03 kPa; 95% CI 0.001 to 0.07 kPa) and a trend to a lower distensibility coefficient (-0.24 10(-3)/kPa; 95% CI -0.49 to 0.02 10(-3)/kPa) of the carotid artery. After adjustment for age, MAP, gender, and GTS, a greater UACR (per quartile) was in addition associated with a shorter carotid-femoral transit time (-1.67 ms; 95% CI -3.24 to -0.10 ms). These associations were not substantially changed by mutual adjustment for eGFR and UACR. In individuals with mild renal insufficiency, both a lower eGFR and a greater albumin excretion, even below levels that are considered to reflect microalbuminuria, are independently associated with greater arterial stiffness. Moreover, these associations were mutually independent. These findings may explain, in part, why eGFR and microalbuminuria are associated with greater risk for CVD and suggest that amelioration of arterial stiffness could be a target of intervention.     

Effect of varicocelectomy on testis volume and semen parameters in adolescents: a meta-analysis

Varicocele repair in adolescent remains controversial. Our aim is to identify and combine clinical trials results published thus far to ascertain the efficacy of varicocelectomy in improving testis volume and semen parameters compared with nontreatment control. A literature search was performed using Medline, Embase and Web of Science, which included results obtained from meta-analysis, randomized and nonrandomized controlled studies. The study population was adolescents with clinically palpable varicocele with or without the testicular asymmetry or abnormal semen parameters. Cases were allocated to treatment and observation groups, and testis volume or semen parameters were adopted as outcome measures. As a result, seven randomized controlled trials (RCTs) and nonrandomized controlled trials studying bilateral testis volume or semen parameters in both treatment and observation groups were identified. Using a random effect model, mean difference of testis volume between the treatment group and the observation group was 2.9 ml (95% confidence interval [CI]: 0.6, 5.2; P< 0.05) for the varicocele side and 1.5 ml (95% CI: 0.3, 2.7; P< 0.05) for the healthy side. The random effect model analysis demonstrated that the mean difference of semen concentration, total semen motility, and normal morphology between the two groups was 13.7 × 10⁶ ml⁻¹ (95% CI: −1.4, 28.8; P = 0.075), 2.5% (95% CI: −3.6, 8.6; P= 0.424), and 2.9% (95% CI: −3.0, 8.7; P= 0.336) respectively. In conclusion, although varicocelectomy significantly improved bilateral testis volume in adolescents with varicocele compared with observation cases, semen parameters did not have any statistically significant difference between two groups. Well-planned, properly conducted RCTs are needed in order to confirm the above-mentioned conclusion further and to explore whether varicocele repair in adolescents could improve subsequently spontaneous pregnancy rates.     

Tumor stiffness measurement using magnetic resonance elastography can predict recurrence and survival after curative resection of hepatocellular carcinoma

BackgroundTumor stiffness measurement using magnetic resonance elastography can assess tumor mechanical properties and predict hepatocellular carcinoma recurrence. This study aimed to investigate preoperative tumor stiffness on magnetic resonance elastography as a predictor of overall survival and recurrence-free survival in patients with solitary nodular hepatocellular carcinoma who underwent curative resection.MethodsSeventy-eight patients with solitary nodular hepatocellular carcinoma who underwent preoperative magnetic resonance elastography and curative resection were retrospectively analyzed. Potential associations of tumor stiffness and other clinicopathological variables with overall survival and recurrence-free survival were analyzed in both univariate and multivariate Cox proportional hazards analyses. The optimal tumor stiffness cutoff value was determined using the minimal P value approach.ResultsIn multivariate analysis, tumor stiffness (hazard ratio 1.31; 95% confidence interval, 1.07–1.59; P = .008) and vascular invasion (hazard ratio 2.62; 95% confidence interval, 1.27–5.17; P = .010) were independent predictors of recurrence-free survival. For overall survival, tumor stiffness (hazard ratio, 1.33; 95% confidence interval, 1.02–1.76; P = .037) was the only independent predictor. The optimal tumor stiffness cutoff value was 5.81 kPa for both overall survival and recurrence-free survival. Patients with tumor stiffness ≥5.81 kPa had a significantly greater risk of death (hazard ratio 6.10; 95% confidence interval, 2.11–21.90; P < .001) than those with tumor stiffness <5.81 kPa.ConclusionPreoperative tumor stiffness as measured by magnetic resonance elastography was a predictor of overall survival and recurrence-free survival in hepatocellular carcinoma patients who underwent curative resection. Higher tumor stiffness was associated with higher risk of recurrence and death.     

Is serum sex hormone-binding globulin a dominant risk factor for metabolic syndrome?

This multi-center, cross-sectional study investigated the association between serum testosterone (T) levels, serum sex hormone-binding globulin (SHBG) levels, and the risk of metabolic syndrome (MS) in 3332 adult Chinese men. The prevalence of MS was 34.7%, and men with MS had lower serum levels of total T (TT) and SHBG than those without MS (P < 0.001). There was no significant difference in serum free T (FT) levels between subjects with and without MS (P = 0.627). In logistic regression analysis, the association between MS and serum SHBG levels persisted after adjusting for age, body mass index (BMI), smoking and drinking status, and serum TT (odds ratio [OR] 0.962, 95% confidence interval [95% CI] 0.954−0.969, P< 0.01). However, the association between serum TT level and the risk of MS was weak after adjusting for age, BMI, SHBG level, and smoking and drinking status (OR 0.981, 95% CI 0.960−1.007). Our study reveals that both serum TT and SHBG levels, but not serum FT, are inversely associated with the prevalence of MS and that serum SHBG is an independent and dominant risk factor for MS.     

Targeted Reduction of Vascular Msx1 and Msx2 Mitigates Arteriosclerotic Calcification and Aortic Stiffness in LDLR-Deficient Mice Fed Diabetogenic Diets

When fed high-fat diets, male LDLR^−/− mice develop obesity, hyperlipidemia, hyperglycemia, and arteriosclerotic calcification. An osteogenic Msx-Wnt regulatory program is concomitantly upregulated in the vasculature. To better understand the mechanisms of diabetic arteriosclerosis, we generated SM22-Cre;Msx1(fl/fl);Msx2(fl/fl);LDLR^−/− mice, assessing the impact of Msx1+Msx2 gene deletion in vascular myofibroblast and smooth muscle cells. Aortic Msx2 and Msx1 were decreased by 95% and 34% in SM22-Cre;Msx1(fl/fl);Msx2(fl/fl);LDLR^−/− animals versus Msx1(fl/fl);Msx2(fl/fl);LDLR^−/− controls, respectively. Aortic calcium was reduced by 31%, and pulse wave velocity, an index of stiffness, was decreased in SM22-Cre;Msx1(fl/fl);Msx2(fl/fl);LDLR^−/− mice vs. controls. Fasting blood glucose and lipids did not differ, yet SM22-Cre;Msx1(fl/fl);Msx2(fl/fl);LDLR^−/− siblings became more obese. Aortic adventitial myofibroblasts from SM22-Cre;Msx1(fl/fl);Msx2(fl/fl);LDLR^−/− mice exhibited reduced osteogenic gene expression and mineralizing potential with concomitant reduction in multiple Wnt genes. Sonic hedgehog (Shh) and Sca1, markers of aortic osteogenic progenitors, were also reduced, paralleling a 78% reduction in alkaline phosphatase (TNAP)–positive adventitial myofibroblasts. RNA interference revealed that although Msx1+Msx2 supports TNAP and Wnt7b expression, Msx1 selectively maintains Shh and Msx2 sustains Wnt2, Wnt5a, and Sca1 expression in aortic adventitial myofibroblast cultures. Thus, Msx1 and Msx2 support vascular mineralization by directing the osteogenic programming of aortic progenitors in diabetic arteriosclerosis.     

Effect of Pentoxifylline on Renal Function and Urinary Albumin Excretion in Patients with Diabetic Kidney Disease: The PREDIAN Trial

Diabetic kidney disease (DKD) is the leading cause of ESRD. We conducted an open-label, prospective, randomized trial to determine whether pentoxifylline (PTF), which reduces albuminuria, in addition to renin-angiotensin system (RAS) blockade, can slow progression of renal disease in patients with type 2 diabetes and stages 3–4 CKD. Participants were assigned to receive PTF (1200 mg/d) (n=82) or to a control group (n=87) for 2 years. All patients received similar doses of RAS inhibitors. At study end, eGFR had decreased by a mean±SEM of 2.1±0.4 ml/min per 1.73 m² in the PTF group compared with 6.5±0.4 ml/min per 1.73 m² in the control group, with a between-group difference of 4.3 ml/min per 1.73 m² (95% confidence interval [95% CI], 3.1 to 5.5 ml/min per 1.73 m²; P<0.001) in favor of PTF. The proportion of patients with a rate of eGFR decline greater than the median rate of decline (0.16 ml/min per 1.73 m² per month) was lower in the PTF group than in the control group (33.3% versus 68.2%; P<0.001). Percentage change in urinary albumin excretion was 5.7% (95% CI, −0.3% to 11.1%) in the control group and −14.9% (95% CI, −20.4% to −9.4%) in the PTF group (P=0.001). Urine TNF-α decreased from a median 16 ng/g (interquartile range, 11–20.1 ng/g) to 14.3 ng/g (interquartile range, 9.2–18.4 ng/g) in the PTF group (P<0.01), with no changes in the control group. In this population, addition of PTF to RAS inhibitors resulted in a smaller decrease in eGFR and a greater reduction of residual albuminuria.     

Compensatory Changes in the Retained Kidney After Nephrectomy in a Living Related Donor

ObjectiveHerein, we investigate the compensatory changes in morphology, function, and hemodynamic indices of the retained kidney after nephrectomy among living related donors.MethodsThe 136 living related kidney donors underwent assessments before surgery as well as at 1 and 12 months, postoperatively, including length, width, short diameter, glomerular filtration rate (GFR), effective renal plasma flow (ERPF), peak systolic blood flow velocity (Vsmax), resistance index (RI), as well as pulsatility indices (PI) of main renal artery (MRA), segmental renal artery (SRA), and interlobar renal artery (IRA).ResultsAll subjects were followed up for 12 to 62 months, with no observed hypertension or kidney failure. The length, width, and short diameters of the retained kidney increased significantly (P < .01) at 1 and 12 months postoperatively. The renal sizes were similar (P > .05). GFR and ERPF increased significantly compared with preoperative values (P < .01) with similar values at postoperative month 1 and 12 (P > .05). The Vsmax of MRA, SRA, and IRA in the retained kidney increased significantly (P < .01); the RI and PI also increased compared with the preoperative values (P < .05), albeit these indicators were similar at postoperative months 1 and 12 (P > .05).ConclusionsFor all subjects studied after unilateral nephrectomy in a living related donor, the diameter of the retained kidney as well as the GFR and ERPF showed compensatory increases. Various arterial hemodynamic parameters also showed compensatory changes. Under strict donor inclusion criteria, living related kidney donor procedures should be safe.     

Drug-Induced Reduction in Albuminuria Is Associated with Subsequent Renoprotection: A Meta-Analysis

Albuminuria has been proposed as a surrogate end point in randomized clinical trials of renal disease progression. Most evidence comes from observational analyses showing that treatment-induced short-term changes in albuminuria correlate with risk change for ESRD. However, such studies are prone to selection bias and residual confounding. To minimize this bias, we performed a meta-analysis of clinical trials to correlate the placebo-corrected drug effect on albuminuria and ESRD to more reliably delineate the association between changes in albuminuria and ESRD. MEDLINE and EMBASE were searched for clinical trials reported between 1950 and April 2014. Included trials had a mean follow-up of ≥1000 patient-years, reported ESRD outcomes, and measured albuminuria at baseline and during follow-up. Twenty-one clinical trials involving 78,342 patients and 4183 ESRD events were included. Median time to first albuminuria measurement was 6 months. Fourteen trials tested the effect of renin-angiotensin-aldosterone-system inhibitors and seven trials tested other interventions. We observed variability across trials in the treatment effect on albuminuria (range, −1.3% to −32.1%) and ESRD (range, −55% to +35% risk change). Meta-regression analysis revealed that the placebo-adjusted treatment effect on albuminuria significantly correlated with the treatment effect on ESRD: for each 30% reduction in albuminuria, the risk of ESRD decreased by 23.7% (95% confidence interval, 11.4% to 34.2%; P=0.001). The association was consistent regardless of drug class (P=0.73) or other patient or trial characteristics. These findings suggest albuminuria may be a valid substitute for ESRD in many circumstances, even taking into account possible other drug-specific effects that may alter renal outcomes.     

A reliable method for renal volume measurement and its application in fenestrated endovascular aneurysm repair

ObjectiveRenal volume has been shown to correlate with renal function. Renal volume and renal function both decline steadily in the sixth decade of life and beyond. We sought to assess (1) the inter-rater reliability for manually measuring renal volume using computed tomography and (2) change in renal volume over time as it relates to renal function in fenestrated endovascular aortic aneurysm repair (FEVAR).MethodsThis study was conducted as part of a physician-sponsored investigational new device (#NCT01538056). First, 30 consecutive kidneys of preoperative FEVAR patients were independently measured by two raters using manual segmentation and three-dimensional modeling software. Renal volumes were calculated and compared. Intraclass correlation was calculated between the two observers. Second, renal volumes were then recorded for 85 patients undergoing FEVAR with follow-up out to 5 years. Demographic data, comorbidities, creatinine, glomerular filtration rate (GFR), renal artery stenosis or occlusion, and bilateral renal volume measurements were analyzed. Multivariate analysis was performed to delineate association of these variables with total renal volume (TRV).ResultsThe intraclass correlation coefficient for our renal volume measurements was 0.97 (95% confidence interval, 0.81-0.99), indicating excellent correlation. Renal volume was strongly correlated with GFR. Our multivariate analysis model predicts a 17.9 mL/min increase in GFR with each 20% increase in TRV. After adjustment for all other known correlates of renal function, renal volume remained as the only significant predictor of renal function.ConclusionsRenal volume can be measured with high reliability using manual segmentation and computed tomography scans. In our baseline analysis, TRV was strongly correlated with renal function. These findings support the potential for renal volume as a surrogate for renal function.     

Incidental parathyroidectomy in thyroidectomy and central neck dissection

BackgroundAlthough higher thyroidectomy volume has been linked with lower complication rates, its association with incidental parathyroidectomy remains less studied. The volume relationship is even less clear for central neck dissection, where individual parathyroid glands are at greater risk.MethodsPatients undergoing thyroidectomy with or without central neck dissection were evaluated for incidental parathyroidectomy, hypoparathyroidism, and hypocalcemia. Univariate and multivariable analyses were performed using binary logistic regression.ResultsOverall, 1,114 thyroidectomies and 396 concurrent central neck dissections were performed across 7 surgeons. Incidental parathyroidectomy occurred in 22.4% of surgeries (range, 16.9%–43.6%), affecting 7.1% of parathyroids at risk (range, 5.8%–14.5%). When stratified by surgeon, lower incidental parathyroidectomy rates were associated with higher thyroidectomy volumes (R² = 0.77, P = .008) and higher central neck dissection volumes (R² = 0.93, P < .001). On multivariable analysis, low-volume surgeon (odds ratio 2.94, 95% confidence interval 2.06–4.19, P < .001), extrathyroidal extension (odds ratio 3.13, 95% confidence interval 1.24–7.87, P = .016), prophylactic central neck dissection (odds ratio 2.68, 95% confidence interval 1.65–4.35, P <.001), and therapeutic central neck dissection (odds ratio 4.44, 95% confidence interval 1.98–9.96, P < .001) were the most significant factors associated with incidental parathyroidectomy. In addition, incidental parathyroidectomy was associated with a higher likelihood of temporary hypoparathyroidism (odds ratio 2.79, 95% confidence interval 1.45–5.38, P = .002) and permanent hypoparathyroidism (odds ratio 4.62, 95% confidence interval 1.41–5.96, P = .025), but not permanent hypocalcemia (odds ratio 1.27, 95% confidence interval 0.48–3.35, P = .63). Higher lymph node yield in central neck dissection was not associated with higher incidental parathyroidectomy rates (odds ratio 1.13, 95% confidence interval 0.85–8.81, P = .82).ConclusionHigher surgical volume conferred a lower rate of incidental parathyroidectomy. Nonetheless, greater lymph node yield in central neck dissections did not result in greater parathyroid-related morbidity. Such findings support the value of leveraging surgical volume to both optimize oncologic resection and minimize complication rates.     

Pulse contour analysis: a valid assessment of central arterial stiffness in children?

In adults the contour analysis of peripheral pressure waves in the upper limb reflects central aortic stiffness. Here, we wanted to demonstrate the appropriateness of pulse contour analysis to assess large artery stiffness in children. Digital volume pulse analysis, with the computation of the stiffness index and pulse wave velocity between carotid and femoral artery, were simultaneously determined in 79 healthy children between 8 years and 15 years (mean age 11.4 years, 32 girls). The stiffness index of 42 healthy adults (mean age 45.6 years, 26 women) served as control. Pulse wave velocity between carotid and femoral artery was directly correlated with systolic pressure and mean blood pressure, as well as with pulse pressure. The results from the stiffness index of children revealed the expected values extrapolated from the linear regression of adulthood stiffness index vs. age. Childhood stiffness index positively correlated with pulse wave velocity (r² = 0.07, P = 0.02) but not with blood pressure parameters. The exclusion of individuals with an increased vascular tone, as indicated by a reflexion index > 90%, improved the correlation between stiffness index and pulse wave velocity (r² = 0.13, P = 0.001). Our data indicate that digital volume pulse-based analysis has limitations if compared with pulse wave velocity to measure arterial stiffness, mostly in patients with a high vascular tone.     

Efficacy of statins on renal function in patients with chronic kidney disease: a systematic review and meta-analysis

BackgroundStudies have shown that the use of statins could significantly improve lipid profiles; however, it remains controversial whether the use of statins could improve renal function in patients with chronic kidney disease (CKD). Therefore, we conducted a meta-analysis of randomized controlled trials (RCTs) to evaluate the effects of statins on renal function in patients with CKD.MethodsWe systematically searched PubMed, EMBASE, and the Cochrane Library databases for eligible RCTs from inception to October 2020. Pooled effect estimates were assigned as weighted mean differences (WMDs) with 95% confidence intervals (CIs) using the random-effects model.ResultsWe selected 33 RCTs that recruited 37,391 patients with CKD patients. The summary results suggested that statin use significantly reduced urinary albumin (WMD: −2.04; 95%CI: −3.53 to −0.56; p = .007) and protein (WMD: −0.58; 95%CI: −0.95 to −0.21; p = .002) excretions and increased creatinine clearance (WMD: 0.86; 95%CI: 0.32–1.41; p = .002). However, there were no significant differences between statin and control groups in terms of changes in estimated glomerular filtration rate (WMD: 0.38; 95%CI: −0.04 to 0.79; p = .075), and serum creatinine levels (WMD: −0.07; 95%CI: −0.25, 0.12; p = .475).ConclusionsWe found that statin use in patients with CKD may slow CKD progression by lowering urinary albumin and protein excretions or increasing creatinine clearance. Further large-scale RCTs should be conducted to evaluate the long-term effects of statins on renal outcomes. Abbreviations: CKD: chronic kidney disease; RCT: randomized controlled trials; WMD: weighted mean differences; CI: confidence intervals; ACEI: angiotensin-converting enzyme inhibitors; eGFR: estimated glomerular filtration rate     

Serum 25-hydroxyvitamin D levels and testosterone deficiency in middle-aged Korean men: a cross-sectional study

Previous studies have demonstrated that male hypogonadism is associated with a low level of vitamin D. However, no reports have investigated the effects of vitamin D on testosterone levels in Korean men. Our aim was to investigate whether testosterone levels are associated with serum vitamin D levels and whether seasonal variation exists. This cross-sectional study analyzed serum 25-hydroxyvitamin D [25(OH)D], total testosterone (TT), and free testosterone (FT) in 652 Korean men over 40 years of age who had undergone a comprehensive medical examination. The average age of the subjects was 56.7 ± 7.9 years, and the mean serum 25(OH)D, TT and FT levels were 21.23 ± 7.9 ng ml⁻¹, 4.70 ± 1.6 ng ml⁻¹, and 8.12 ± 3.3 pg ml⁻¹, respectively. In the multiple linear regression model, 25(OH)D showed positive association with TT (β =0.137, P < 0.001) and FT (β =0.103, P = 0.008). 25(OH)D and FT showed similar seasonal or monthly variation after adjustment for age. A vitamin D deficiency [25(OH)D < 20 ng ml⁻¹] was associated with an increased risk of deficiencies of TT (<2.30 ng ml⁻¹) (odds ratio [OR]: 2.65; 95% confidence interval [CI]: 1.21–5.78, P = 0.014) and FT (<6.50 pg ml⁻¹) (OR: 1.44; 95% CI: 1.01–2.06 P = 0.048) after adjusting for age, season, body mass index, body composition, chronic disease, smoking, and alcohol use. In conclusion, we demonstrated a positive correlation between 25(OH)D and testosterone, which showed similar seasonal variation in Korean men.     

Environmental mercury exposure,semen quality and reproductive hormones in Greenlandic Inuit and European men: a cross-sectional study

Several animal studies indicate that mercury is a male reproductive toxicant, but human studies are few and contradictory. We examined semen characteristics and serum levels of reproductive hormones in relation to environmental exposure to mercury. Blood and semen samples were collected from 529 male partners of pregnant women living in Greenland, Poland and Ukraine between May 2002 and February 2004. The median concentration of the total content of mercury in whole blood was 9.2 ng ml⁻¹ in Greenland (0.2–385.8 ng ml⁻¹), 1.0 ng ml⁻¹ in Poland (0.2–6.4 ng ml⁻¹) and 1.0 ng ml⁻¹ in Ukraine (0.2–4.9 ng ml⁻¹). We found a significantly positive association between the blood levels of mercury and serum concentration of inhibin B in men from Greenland (β=0.074, 95% confidence interval (CI)=0.021 to 0.126) and in an analysis including men from all three regions (β=0.067, 95% CI=0.024 to 0.110). The association may be due to beneficial effects of polyunsaturated fatty acids (PUFAs), which are contained in seafood and fish. No significant association (P>0.05) was found between blood concentrations of mercury and any of the other measured semen characteristics (semen volume, total sperm count, sperm concentration, morphology and motility) and reproductive hormones (free androgen index (FAI), follicle-stimulating hormone (FSH), luteinizing hormone (LH), testosterone and LH×testosterone) in any region. In conclusion, the findings do not provide evidence that environmental mercury exposure in Greenlandic and European men with median whole blood concentration up to 10 ng ml⁻¹ has adverse effects on biomarkers of male reproductive health.     

Effect of varicocele on semen characteristics according to the new 2010 World Health Organization criteria: a systematic review and meta-analysis

This study investigated the effects of varicocele on semen parameters in infertile men based on the new 2010 World Health Organization laboratory manual for the examination of human semen. Semen analysis results (volume, sperm count, motility, and morphology) were the primary outcomes. An electronic search to collect the data was conducted using the Medline/PubMed, SJU discover, and Google Scholar databases. We searched articles published from 2010 to August 2015, i.e., after the publication of the 2010 WHO manual. We included only those studies that reported the actual semen parameters of adult infertile men diagnosed with clinical varicocele and contained a control group of either fertile men or normozoospermic men who were not diagnosed with varicocele. Ten studies were included in the meta-analysis, involving 1232 men. Varicocele was associated with reduced sperm count (mean difference: −44.48 × 10⁶ ml⁻¹; 95% CI: −61.45, −27.51 × 10⁶ ml⁻¹; P < 0.001), motility (mean difference: −26.67%; 95% CI: −34.27, −19.08; P < 0.001), and morphology (mean difference: −19.68%; 95% CI: −29.28, −10.07; P < 0.001) but not semen volume (mean difference: −0.23 ml; 95% CI: −0.64, 0.17). Subgroup analyses indicated that the magnitude of effect was influenced by control subtype but not WHO laboratory manual edition used for semen assessment. We conclude that varicocele is a significant risk factor that negatively affects semen quality, but the observed pooled effect size on semen parameters does not seem to be affected by the WHO laboratory manual edition. Given most of the studies published after 2010 still utilized the 1999 manual for semen analysis, further research is required to fully understand the clinical implication of the 2010 WHO laboratory manual on the association between varicocele and semen parameters.     

Risk Factors for Hypoxemia After Surgery for Acute Type A Aortic Dissection

Purpose Postoperative hypoxemia is a frequent complication of surgery for acute type A aortic dissection. We tried to determine the factors associated with postoperative hypoxemia. Methods Between 1997 and 2003, 114 patients underwent surgery for acute type A aortic dissection. Multivariate logistic regression analysis was done to identify the independent predictors of postoperative hypoxemia, defined by an arterial partial oxygen/inspired oxygen fraction (PaO₂/FiO₂) ratio of 200 or lower. Results The overall in-hospital mortality was 6.1% (7 of 114 patients), being 5.2% in the hypoxemia group and 6.9% in the non-hypoxemia group. The ventilation time and intensive care unit stay were significantly longer in the hypoxemia group than in the non-hypoxemia group (P = 0.0044, P = 0.038, respectively). Logistic regression identified the following variables as predictors for postoperative hypoxemia: body mass index ≥25 (odds ratio [OR], 5.6; 95% confidence interval [CI], 2.1–15.01; P < 0.001), preoperative PaO₂/FiO₂ ratio ≤300 (OR, 2.6; 95% CI, 1.09–6.13; P = 0.031), and the volume of transfused blood (OR, 1.08; 95% CI, 1.01–1.18; P = 0.037). Conclusions Initiating early treatment for hypoxemia and reducing the volume of blood transfused intraoperatively may improve the postoperative clinical course of obese patients with preoperative hypoxemia.