Michael A. Mao

The risk of coronary heart disease in patients with kidney stones: A systematic review and meta-analysis

Background: The reported risk of coronary heart disease (CHD) in patients with a history of kidney stones is conflicting. Aims: The objective of this meta-analysis was to assess the association between a history of kidney stones and CHD risk. Materials and Methods: A literature search was performed using MEDLINE, EMBASE, and Cochrane Database of Systematic Reviews from inception until April 04, 2014. Studies that reported odds ratios or hazard ratios comparing the risk of CHD in patients with a history of kidney stones versus those without a history of kidney stones were included. Pooled risk ratios (RRs) and 95% confidence interval (CI) were calculated using a random-effect, generic inverse variance method. Results: Seven study populations from four cohort studies and one cross-sectional study were identified and included in the data analysis. The pooled risk ratio (RR) of CHD in patients with kidney stones was 1.24 (95% CI, 1.10-1.40). This result remained significant (RR, 1.23 [95% CI, 1.08-1.41]) when the sensitivity analysis was restricted to only cohort studies. A history of kidney stones was associated with increased CHD risk in females (RR, 1.43 [95% CI, 1.12-1.82]), whereas the association was not significant in males (RR, 1.14 [95% CI, 0.94-1.38]). Conclusions: Our study demonstrates a statistically significant increased risk of CHD in female patients with prior kidney stones. This finding suggests that a history of kidney stones is a risk factor for CHD in females and may impact clinical management.

Hypomagnesaemia linked to depression: a systematic review and meta‐analysis

The reported risk of depression in patients with hypomagnesaemia is controversial.

The effect of renin-angiotensin system inhibitors on kidney allograft survival: A systematic review and meta-analysis

Background: The use of renin-angiotensin system (RAS) inhibitors in patients with chronic kidney disease, and especially in diabetic kidney disease, has been shown to provide renoprotective effects and slow progression to end-stage renal disease. However, this protective effect in kidney transplant patient populations is unclear. Aim: The objective of this systematic review and meta-analysis was to evaluate the effect of RAS inhibitors on kidney allograft survival. Materials and Methods: A literature search for randomized controlled trials (RCTs) was performed from inception through February 2016. Studies that reported relative risks or hazard ratios comparing the risks of renal graft loss in renal transplant recipients who received RAS inhibitors vs. controls were included. Pooled risk ratios (RRs) and 95% confidence intervals (CIs) were calculated using a random-effect, generic inverse variance method. Results: Five studies (3 RCTs and 2 cohort studies) with 20024 kidney transplant patients were included in the meta-analysis. Pooled RR of allograft failure in recipients who received RAS inhibitors was 0.73 (95% CI: 0.45-1.21). When meta-analysis was limited only to RCTs, the pooled RR of allograft failure in patients using RAS inhibitors was 0.59 (95%: CI 0.20-1.69). The risk for mortality (RR: 1.13 [95% CI: 0.62-2.07]) in patients using RAS inhibitors compared to controls was not significantly reduced. Conclusion: This meta-analysis demonstrated insignificant reduced risks of renal graft loss among renal transplant recipients who received RAS inhibitors. Future studies assessing the potential benefits of RAS inhibitors on allograft survival in specific kidney transplant patient populations are needed.

Contrast-induced acute kidney injury in kidney transplant recipients: A systematic review and meta-analysis

AIM To evaluate the incidence of contrast-induced acute kidney injury (CIAKI) in kidney transplant recipients. METHODS A literature search was performed using MEDLINE, EMBASE, and the Cochrane Database of Systematic Reviews from the inception of the databases through July 2016. Studies assessing the incidence of CIAKI in kidney transplant recipients were included. We applied a random-effects model to estimate the incidence of CIAKI. RESULTS Six studies of 431 kidney transplant recipients were included in the analyses to assess the incidence of CIAKI in kidney transplant recipients. The estimated incidence of CIAKI and CIAKI-requiring dialysis were 9.6% (95%CI: 4.5%-16.3%) and 0.4% (95%CI: 0.0%-1.2%), respectively. A sensitivity analysis limited only to the studies that used low-osmolar or iso-osmolar contrast showed the estimated incidence of CIAKI was 8.0% (95%CI: 3.5%-14.2%). The estimated incidences of CIAKI in recipients who received contrast media with cardiac catheterization, other types of angiogram, and CT scan were 16.1% (95%CI: 6.6%-28.4%), 10.1% (95%CI: 4.2%-18.0%), and 6.1% (95%CI: 1.8%-12.4%), respectively. No graft losses were reported within 30 d post-contrast media administration. However, data on the effects of CIAKI on long-term graft function were limited. CONCLUSION The estimated incidence of CIAKI in kidney transplant recipients is 9.6%. The risk stratification should be considered based on allograft function, indication, and type of procedure.

Persistent acute kidney injury following transcatheter aortic valve replacement

Acute kidney injury (AKI) and its severity after transcatheter aortic valve replacement (TAVR) have been associated with worse outcomes. Studies have shown that AKI duration (transient or persistent) affects outcomes independently of AKI severity. This study was undertaken to determine the association, risk factors, and outcomes associated with persistent AKI (pAKI) after TAVR.

Impact of admission serum potassium on mortality in patients with chronic kidney disease and cardiovascular disease

Background Little is known about the effect of admission potassium (K) on risk of in-hospital mortality in chronic kidney disease (CKD) and cardiovascular disease (CVD) patients. Aim The aim of this study was to assess the relationship between admission serum K and in-hospital mortality in all hospitalized patients stratified by CKD and/or CVD status. Design and Methods All adult hospitalized patients who had admission serum K between years 2011 and 2013 were enrolled. Admission serum K was categorized into seven groups (<3.0, 3.0-3.5, 3.5-4.0, 4.0-4.5, 4.5-5.0, 5.0-5.5 and ≥5.5 mEq/L). The odds ratio (OR) of in-hospital mortality by admission serum K, using K 4.0-4.5 mEq/L as the reference group, was obtained by logistic regression analysis. Results 73,983 patients were studied. The lowest incidence of in-hospital mortality was associated with serum K within 4.0-4.5 mEq/L. A U-shaped curve emerged demonstrating higher in-hospital mortality associated with both serum K < 4.0 and >4.5 mEq/L. After adjusting for potential confounders, both serum K < 4.0 mEq/L and >5.0 mEq/L were associated with increased in-hospital mortality with ORs of 3.26 (95% CI 2.03-4.98), 2.40 (95% CI 1.89-3.04), 1.38 (95%CI 1.15-1.66), 1.89 (95% CI 1.49-2.38) and 3.62 (95%CI 2.73-4.76) when serum K were within <3.0, 3.0-3.5, 3.5-4.0, 5.0-5.5, and ≥5.5 mEq/L, respectively. In CVD patients, the highest in-hospital mortality was associated with serum K < 3.0 mEq/L (OR 1.70, 95%CI 1.31-2.18). In CKD patients, the highest in-hospital mortality was associated with serum K ≥ 5.5 mEq/L (OR 3.26, 95%CI 2.14-4.90). Conclusion Admission serum K < 4.0 mEq/L and >5.0 mEq/L were associated with increased in-hospital mortality. The mortality risk among patients with various admission potassium levels was affected by CKD and/or CVD status.

Incidence, Severity, and Outcomes of Acute Kidney Injury in Octogenarians following Heart Valve Replacement Surgery

Background. The study investigates the occurrence, severity, and outcomes of acute kidney injury (AKI) in octogenarians following heart valve surgery. Methods. All patients, age >80 years, not on dialysis and without kidney transplant, undergoing heart valve replacement at Mayo Clinic, Rochester, in the years 2002-2003 were enrolled. AKI was diagnosed based on AKIN criteria. Results. 209 octogenarians (88.0% aortic valve, 6.2% mitral valve, 1.0% tricuspid valve, and 4.8% multivalve) with (58.4%) and without CABG were studied. 34 (16.3%) had preexisting CKD. After surgery, 98 (46.8%) developed AKI. 76.5% of the AKI were in Stage 1, 9.2% in Stage 2, and 14.3% in Stage 3. 76.5% CKD patients developed AKI. Length of hospital stay was longer for AKI patients. More AKI patients were discharged to care facilities. Patient survival at 30 days and 1 year for AKI versus non-AKI was 88.8 versus 98.7%, p = 0.003, and 76.5 versus 88.3%, p = 0.025, respectively. With follow-up of 3.94 ± 0.28 years, Kaplan-Meier analysis showed a reduced survival for AKI octogenarians. Preexisting CKD and large volume intraoperative fluid administration were independent AKI predictors. Conclusions. Nearly half of the octogenarians developed AKI after valve replacement surgery. AKI was associated with significant functional impairment and reduced survival.

Admission calcium levels and risk of acute kidney injury in hospitalised patients

The risk of acute kidney injury (AKI) development among hospitalised patients with elevated calcium levels on admission remains unclear. The aim of this study was to assess the risk of AKI in hospitalised patients stratified by various admission serum calcium levels.

Associations of rotational shift work and night shift status with hypertension: a systematic review and meta-analysis

Background: The reported risks of hypertension (HTN) in rotating shift and night shift workers are controversial. The objective of this meta-analysis was to assess the association between shift work status and HTN. Methods: A literature search was performed using MEDLINE, EMBASE and Cochrane Database from inception through October 2016. Studies that reported odds ratios (OR) comparing the risk of HTN in shift workers were included. A prespecified subgroup analysis by rotating shift and night shift statuses were also performed. Pooled OR and 95% confidence interval (CI) were calculated using a random-effect, generic inverse variance method. The protocol for this study is registered with International Prospective Register of Systematic Reviews; no. CRD42016051843. Results: Twenty-seven observational studies (nine cohort and 18 cross-sectional studies) with a total of 394 793 individuals were enrolled. The pooled ORs of HTN in shift workers in cohort and cross-sectional studies were 1.31 (95% CI, 1.07–1.60) and 1.10 (95% CI, 1.00–1.20), respectively. When meta-analysis was restricted only to cohort studies in rotating shift, the pooled OR of HTN in rotating shift workers was 1.34 (95% CI, 1.08–1.67). The data regarding night shift and HTN in cohort studies was limited. The pooled OR of HTN in night shift workers in cross-sectional studies was 1.07 (95% CI, 0.85–1.35). Conclusion: Based on the findings of our meta-analysis, shiftwork status may play an important role in HTN, as there is a significant association between rotating shift work and HTN. However, there is no significant association between night shift status and risk of HTN.

Primary IgA nephropathy in elderly patients

Data on clinicopathological features, treatment and outcomes of IgA nephropathy (IgAN) in elderly patients are limited.