A prospective controlled study of metabolic and physiologic effects of kidney donation suggests that donors retain stable kidney function over the first nine years

While there have been numerous studies of living kidney donors, most have been retrospective without suitable controls and have yielded conflicting results. To clarify this we studied 205 living donor candidates and 203 controls having no medical conditions precluding donation. Before and at six months, one, two, three, six, and nine years after donation we measured iohexol glomerular filtration rate, clinic blood pressure, urine protein excretion and metabolic parameters reported to be affected by kidney function. We measured 24 hour ambulatory blood pressure at three, six, and nine years and at six and nine years blood pressure after treadmill exercise, carotid-femoral pulse wave velocity and arterial elasticity. Between six months and nine years, the mean (95% confidence interval) change in glomerular filtration rate was significantly different among 133 donors 0·02 (-0·16-0·20) mL/min/1·73m²/year versus -1·26 (-1·52--1·00) mL/min/1·73m²/year in 113 healthy controls. Blood pressure, urine protein, urine albumin, glucose, hemoglobin A1c, insulin, and lipoproteins were not different in controls versus donors; but parathyroid hormone, homocysteine and uric acid remained higher at nine years. At six and nine years carotid-femoral pulse wave velocity was not different, but the mean small artery elasticity was significantly lower in 141 donors 6·1 mL/mmHg x100, versus 113 controls 7·1 mL/mmHg x100, and 6·1 mL/mmHg x100 in 137 donors versus 7·6 mL/mmHg x100 in 112 controls at six and nine years, respectively [significant adjusted difference of 1·1 mL/mmHg x100]. Thus, donors remain healthy with stable kidney function for the first nine years, but differences in metabolic and vascular parameters could be harbingers of adverse outcomes requiring future interventions.

Treatment for presumed BK polyomavirus nephropathy and risk of urinary tract cancers among kidney transplant recipients in the United States

Recent case series describe detection of BK polyomavirus (BKV) in urinary tract cancers in kidney transplant recipients, suggesting that BKV could contribute to the development of these cancers. We assessed risk for urinary tract cancers in kidney recipients with or without treatment for presumed BKV nephropathy (tBKVN) using data from the United States Transplant Cancer Match Study (2003-2013). Among 55 697 included recipients, 2015 (3.6%) were reported with tBKVN. Relative to the general population, incidence was similarly elevated (approximately 4.5-fold) for kidney cancer in recipients with or without tBKVN, and incidence was not increased in either group for prostate cancer. In contrast, for invasive bladder cancer, incidence was more strongly elevated in recipients with versus without tBKVN (standardized incidence ratios 4.5 vs. 1.7; N = 48 cases), corresponding to an incidence rate ratio (IRR) of 2.9 (95% confidence interval [CI] 1.0-8.2), adjusted for sex, age, transplant year, and use of polyclonal antibody induction. As a result, recipients with tBKVN had borderline increased incidence for all urothelial cancers combined (renal pelvis, ureter, and bladder cancers: adjusted IRR 2.2, 95% CI 0.9-5.4; N = 89 cases). Together with reports describing BKV detection in tumor tissues, these results support an association between BKV and urothelial carcinogenesis among kidney transplant recipients.

Abnormalities in biomarkers of mineral and bone metabolism in kidney donors

Previous studies have suggested that kidney donors may have abnormalities of mineral and bone metabolism typically seen in chronic kidney disease. This may have important implications for the skeletal health of living kidney donors and for our understanding of the pathogenesis of long-term mineral and bone disorders in chronic kidney disease. In this prospective study, 182 of 203 kidney donors and 173 of 201 paired normal controls had markers of mineral and bone metabolism measured before and at 6 and 36 months after donation (ALTOLD Study). Donors had significantly higher serum concentrations of intact parathyroid hormone (24.6% and 19.5%) and fibroblast growth factor-23 (9.5% and 8.4%) at 6 and 36 months, respectively, as compared to healthy controls, and significantly reduced tubular phosphate reabsorption (-7.0% and -5.0%) and serum phosphate concentrations (-6.4% and -2.3%). Serum 1,25-dihydroxyvitamin D3 concentrations were significantly lower (-17.1% and -12.6%), while 25-hydroxyvitamin D (21.4% and 19.4%) concentrations were significantly higher in donors compared to controls. Moreover, significantly higher concentrations of the bone resorption markers, carboxyterminal cross-linking telopeptide of bone collagen (30.1% and 13.8%) and aminoterminal cross-linking telopeptide of bone collagen (14.2% and 13.0%), and the bone formation markers, osteocalcin (26.3% and 2.7%) and procollagen type I N-terminal propeptide (24.3% and 8.9%), were observed in donors. Thus, kidney donation alters serum markers of bone metabolism that could reflect impaired bone health. Additional long-term studies that include assessment of skeletal architecture and integrity are warranted in kidney donors.

Association between Renal Function and Bleeding Risk for Dabigatran after Switching from Warfarin

BACKGROUND

There is a higher risk of gastrointestinal (GI) bleeding in patients treated with dabigatran versus warfarin. We analyzed the impact of renal function on the relative risk of bleeding in patients converted to dabigatran.

METHODS

Patients aged ≥65 years who received anticoagulation with warfarin for a minimum of 6 months and subsequently converted to dabigatran or remained on warfarin were studied. Data sources included VA National Patient Care, and VA Decision Support System National Pharmacy and Laboratory. Each patient who converted to dabigatran 150 mg twice daily was matched by propensity score with 2 patients on warfarin who did not convert. Outcomes included rates of hospital admission for GI or other major bleeding and mortality, stratified by estimated glomerular filtration rate (eGFR).

RESULTS

Study population included 864 patients who converted and 1,710 patients who did not convert to dabigatran. In patients with eGFR 50-80 ml/min/1.73 m², the hazard of GI bleeding in patients who initiated dabigatran was nearly 3 times higher, (4.1 vs. 1.3 per 100 patient years; hazards ratio 2.94; 95% CI 1.24-7.02; p = 0.015), compared to patients who remained on warfarin. There were relatively few patients with eGFR <50 or >80 ml/min/1.73 m2, and relatively few bleeding events outside the GI tract.

CONCLUSIONS

Prescribing healthcare providers should exercise caution and close monitoring for bleeding complications when converting from warfarin to dabigatran, even in patients with renal function in the range considered safe for dabigatran use as per current recommendations.

Risk of cancer in retransplants compared to primary kidney transplants in the United States

Recipients of kidney transplantation have elevated risk of developing cancer. There are limited data on cancer risk in recipients of kidney retransplantation. We used data from the Transplant Cancer Match Study, which links the U.S. transplant registry with 15 cancer registries. Cancer incidence in recipients of kidney retransplantation and primary kidney transplants was compared utilizing Poisson regression, adjusting for demographic and medical characteristics. We assessed 109 224 primary recipients and 6621 retransplants. Compared to primary recipients, retransplants were younger (median age 40 vs. 46 yr), had higher PRA, and more often received induction with polyclonal antibodies (43% vs. 25%). A total of 5757 cancers were observed in primary recipients and 245 in retransplants. Overall cancer risk was similar in retransplants compared with primary recipients (incidence rate ratio [IRR] 1.06, 95% CI 0.93-1.20, adjusted for age, gender, race/ethnicity, PRA, and use of polyclonal induction). However, renal cell carcinoma (RCC) occurred in excess among retransplants (adjusted IRR 2.03, 95% CI 1.45-2.77), based on 514 cases in primary recipients and 43 cases in retransplants. Overall cancer risk did not differ in retransplants compared to primary recipients. Increased risk of RCC may be explained by the presence of acquired cystic kidney disease, which is more likely to develop with additional time with kidney disease and time spent on dialysis waiting for retransplantation.

Kidney Function and Cardiovascular Events in Postmenopausal Women: The Impact of Race and Ethnicity in the Women's Health Initiative

BACKGROUND

Kidney disease disproportionately affects minority populations, including African Americans and Hispanics; therefore, understanding the relationship of kidney function to cardiovascular (CV) outcomes within different racial/ethnic groups is of considerable interest. We investigated the relationship between kidney function and CV events and assessed effect modification by race/ethnicity in the Women's Health Initiative.

STUDY DESIGN

Prospective cohort study.

SETTING & PARTICIPANTS

Baseline serum creatinine concentrations (assay traceable to isotope-dilution mass spectrometry standard) of 19,411 postmenopausal women aged 50 to 79 years who self-identified as either non-Hispanic white (n=8,921), African American (n=7,436), or Hispanic (n=3,054) were used to calculate estimated glomerular filtration rates (eGFRs).

PREDICTORS

Categories of eGFR (exposure); race/ethnicity (effect modifier).

OUTCOMES

The primary outcome was the composite of 3 physician-adjudicated CV events: myocardial infarction, stroke, or CV-related death.

MEASUREMENTS

We evaluated the multivariable-adjusted associations between categories of eGFR and CV events using proportional hazards regression and formally tested for effect modification by race/ethnicity.

RESULTS

During a mean follow-up of 7.6 years, 1,424 CV events (653 myocardial infarctions, 627 strokes, and 297 CV-related deaths) were observed. The association between eGFR and CV events was curvilinear; however, the association of eGFR with CV outcomes differed by race (P=0.006). In stratified analyses, we observed that the U-shaped association was present in non-Hispanic whites, whereas African American participants had a rather curvilinear relationship, with lower eGFR being associated with higher CV risk, and higher eGFR, with reduced CV risk. Analyses among Hispanic women were inconclusive owing to few Hispanic women having very low or high eGFRs and very few events occurring in these categories.

LIMITATIONS

Lack of urinary albumin measurements; residual confounding by unmeasured or imprecisely measured characteristics.

CONCLUSIONS

In postmenopausal women, the patterns of association between eGFR and CV risk differed between non-Hispanic whites and African American women.

Effect of extended-release niacin on cardiovascular events and kidney function in chronic kidney disease: a post hoc analysis of the AIM-HIGH trial

Chronic kidney disease (CKD) in patients is strongly associated with cardiovascular morbidity and mortality, and prevalent abnormal lipid metabolism. The AIM-HIGH trial examined the benefits of adding extended-release niacin (ERN) to simvastatin in patients with established coronary heart disease. Here we conducted a post hoc analysis of the AIM-HIGH trial examining whether participants derived cardiovascular or renal benefits when stratified by renal function. Of 3414 participants, 505 had stage 3 CKD at baseline. Among the CKD subset, demographics and cardiovascular disease (CVD) risk factors were well balanced in the ERN and placebo arms. Compared with placebo, CKD participants receiving ERN had a significant decrease in triglycerides by a median of 59.0 mg/dl, and high-density lipoprotein cholesterol significantly increased by a mean of 11.3 mg/dl over a mean follow-up of 3 years. CVD events were similar between CKD participants in both arms. However, all-cause mortality was significantly higher in the ERN group (hazard ratio of 1.73). Mean change in eGFR among ERN-treated CKD participants was not significantly different between study arms. Thus, among AIM-HIGH participants with CKD, the addition of ERN to simvastatin for secondary prevention of CVD improved triglyceride and high-density lipoprotein-cholesterol concentrations but did not improve cardiovascular outcomes or kidney function, and was associated with higher all-cause mortality.

A prospective controlled study of living kidney donors: three-year follow-up

BACKGROUND

There have been few prospective controlled studies of kidney donors. Understanding the pathophysiologic effects of kidney donation is important for judging donor safety and improving our understanding of the consequences of reduced kidney function in chronic kidney disease.

STUDY DESIGN

Prospective, controlled, observational cohort study.

SETTING & PARTICIPANTS

3-year follow-up of kidney donors and paired controls suitable for donation at their donor's center.

PREDICTOR

Kidney donation.

OUTCOMES

Medical history, vital signs, glomerular filtration rate, and other measurements at 6, 12, 24, and 36 months after donation.

RESULTS

At 36 months, 182 of 203 (89.7%) original donors and 173 of 201 (86.1%) original controls continue to participate in follow-up visits. The linear slope of the glomerular filtration rate measured by plasma iohexol clearance declined 0.36±7.55mL/min per year in 194 controls, but increased 1.47±5.02mL/min per year in 198 donors (P=0.005) between 6 and 36 months. Blood pressure was not different between donors and controls at any visit, and at 36 months, all 24-hour ambulatory blood pressure parameters were similar in 126 controls and 135 donors (mean systolic blood pressure, 120.0±11.2 [SD] vs 120.7±9.7mmHg [P=0.6]; mean diastolic blood pressure, 73.4±7.0 vs 74.5±6.5mmHg [P=0.2]). Mean arterial pressure nocturnal dipping was manifest in 11.2% ± 6.6% of controls and 11.3% ± 6.1% of donors (P=0.9). Urinary protein-creatinine and albumin-creatinine ratios were not increased in donors compared with controls. From 6 to 36 months postdonation, serum parathyroid hormone, uric acid, homocysteine, and potassium levels were higher, whereas hemoglobin levels were lower, in donors compared with controls.

LIMITATIONS

Possible bias resulting from an inability to select controls screened to be as healthy as donors, short follow-up duration, and dropouts.

CONCLUSIONS

Kidney donors manifest several of the findings of mild chronic kidney disease. However, at 36 months after donation, kidney function continues to improve in donors, whereas controls have expected age-related declines in function.

Conversion to a sirolimus-based regimen is associated with lower incidence of BK viremia in low-risk kidney transplant recipients

BACKGROUND

BK viral nephropathy is an increasingly recognized cause of early allograft loss in kidney transplantation. This study aimed to determine whether a sirolimus (Sir)-based calcineurin inhibitor-sparing regimen is associated with a lower incidence of BK viremia.

METHODS

This was a single-center retrospective study. Patients were either on tacrolimus (Tac)-based or on Sir-based immunosuppression. Conversion from Tac to Sir occurred at or after 3 months if patients were <62 years of age, had calculated panel reactive antibodies of <20%, and did not have acute early rejection.

RESULTS

Incidence of clinically significant BK viremia was 17.9% in the Tac group and 4.3% in the Sir group. Cox regression multivariate analysis showed that male gender (hazard ratio [HR] = 2.87) and switch to Sir (HR = 0.333) impacted the incidence of BK viremia. Kaplan-Meier analysis showed a higher BK-free survival in the Sir group. A trend was seen toward shorter time to resolution of BK viremia and lower peak viremia in the Sir group. Patients on Sir had a higher estimated glomerular filtration rate at each time point; 34% of patients discontinued Sir because of side effects.

CONCLUSION

Conversion to Sir-based maintenance immunosuppression at or about 3 months after kidney transplantation correlates with a lower incidence of BK viremia.

A prospective controlled study of kidney donors: baseline and 6-month follow-up

BACKGROUND

Most previous studies of living kidney donors have been retrospective and have lacked suitable healthy controls. Needed are prospective controlled studies to better understand the effects of a mild reduction in kidney function from kidney donation in otherwise healthy individuals.

STUDY DESIGN

Prospective, controlled, observational cohort study.

SETTING & PARTICIPANTS

Consecutive patients approved for donation at 8 transplant centers in the United States were asked to participate. For every donor enrolled, an equally healthy control with 2 kidneys who theoretically would have been suitable to donate a kidney also was enrolled.

PREDICTOR

Kidney donation.

MEASUREMENTS

At baseline predonation and at 6 months after donation, medical history, vital signs, measured (iohexol) glomerular filtration rate, and other measurements were collected. There were 201 donors and 198 controls who completed both baseline and 6-month visits and form the basis of this report.

RESULTS

Compared with controls, donors had 28% lower glomerular filtration rates at 6 months (94.6 ± 15.1 [SD] vs 67.6 ± 10.1 mL/min/1.73 m(2); P < 0.001), associated with 23% greater parathyroid hormone (42.8 ± 15.6 vs 52.7 ± 20.9 pg/mL; P < 0.001), 5.4% lower serum phosphate (3.5 ± 0.5 vs 3.3 ± 0.5 mg/dL; P < 0.001), 3.7% lower hemoglobin (13.6 ± 1.4 vs 13.1 ± 1.2 g/dL; P < 0.001), 8.2% greater uric acid (4.9 ± 1.2 vs 5.3 ± 1.1 mg/dL; P < 0.001), 24% greater homocysteine (1.2 ± 0.3 vs 1.5 ± 0.4 mg/L; P < 0.001), and 1.5% lower high-density lipoprotein cholesterol (54.9 ± 16.4 vs 54.1 ± 13.9 mg/dL; P = 0.03) levels. There were no differences in albumin-creatinine ratios (5.0 [IQR, 4.0-6.6] vs 5.0 [IQR, 3.3-5.4] mg/g; P = 0.5), office blood pressures, or glucose homeostasis.

LIMITATIONS

Short duration of follow-up and possible bias resulting from an inability to screen controls with kidney and vascular imaging performed in donors.

CONCLUSIONS

Kidney donors have some, but not all, abnormalities typically associated with mild chronic kidney disease 6 months after donation. Additional follow-up is warranted.

Dissociation between progression of coronary artery calcification and endothelial function in hemodialysis patients: a prospective pilot study

Chronic kidney disease profoundly disturbs calcium-phosphate metabolism and predisposes to premature atherosclerosis. Both coronary artery calcification (CAC) and endothelial dysfunction are common in hemodialysis (HD) patients. We hypothesized that a calcium-free phosphate binder would improve endothelial function and delay progression of vascular calcification in HD patients.

METHODS

This was a randomized parallel-group trial in HD patients comparing lanthanum carbonate (LC) with a non-LC phosphorus binders control group (non-LC) at a 1 : 1 randomization. CAC was obtained at baseline, 6, and 12 months, and endothelial function (brachial artery flow-mediated dilation - FMD) at baseline and 6 months.

RESULTS

13 patients were randomized (LC n = 7 and non-LC n = 6). CAC scores (Log ± SE) at baseline were 7.21 ± 0.62 (LC) and 6.07 ± 0.73 (control). CAC increased in the non-LC group (33 ± 17% and 77 ± 22% at 6 and 12 months), but tended to decrease in the LC group (-10 ± 11% and -2 ± 11% at 6 and 12 months). There was statistically less progression in CAC in the LC group compared to control at 6 (p = 0.002) and 12 months (p = 0.003). There was no difference between groups in FMD (p = 0.7). Markers of inflammation did not change significantly.

CONCLUSION

A slower rate of progression of CAC occurred in the LC group, independent of changes in FMD. This is the first study showing dissociation between progression of CAC and FMD in HD patients. Larger studies are warranted to elucidate the impact of different phosphate sequestration therapies on atherosclerosis in HD patients.

Recommendations for the assessment and reporting of multivariable logistic regression in transplantation literature

Multivariable logistic regression is an important method to evaluate risk factors and prognosis in solid organ transplant literature. We aimed to assess the quality of this method in six major transplantation journals. Eleven analytical criteria and four documentation criteria were analyzed for each selected article that used logistic regression. A total of 106 studies (6%) out of 1,701 original articles used logistic regression analyses from January 1, 2005 to January 1, 2006. The analytical criteria and their respective reporting percentage among the six journals were: Linearity (25%); Beta coefficient (48%); Interaction tests (19%); Main estimates (98%); Ovefitting prevention (84%); Goodness-of-fit (3.8%); Multicolinearity (4.7%); Internal validation (3.8%); External validation (8.5%). The documentation criteria were reported as follows: Selection of independent variables (73%); Coding of variables (9%); Fitting procedures (49%); Statistical program (65%). No significant differences were found among different journals or between general versus subspecialty journals with respect to reporting quality. We found that the report of logistic regression is unsatisfactory in transplantation journals. Because our findings may have major consequences for the care of transplant patients and for the design of transplant clinical trials, we recommend a practical solution for the use and reporting of logistic regression in transplantation journals.

Older donor livers show early severe histological activity, fibrosis, and graft failure after liver transplantation for hepatitis C

BACKGROUND

In hepatitis C virus (HCV)-positive liver transplant recipients, infection of the allograft and recurrent liver disease are important problems. Increased donor age has emerged as an important variable affecting patient and graft survival; however, specific age cutoffs and risk ratios for poor histologic outcomes and graft survival are not clear.

METHODS

A longitudinal database of all HCV-positive patients transplanted at our center during an 11-year period was used to identify 111 patients who received 124 liver transplants. Graft survival and histological endpoints (severe activity and fibrosis) of HCV infection in the allografts were compared as a function of donor age at transplantation.

RESULTS

By Kaplan-Meier analyses, older allografts showed earlier failure and decreased time to severe histological activity and fibrosis as compared with allografts from younger donors. By Cox proportional hazards analysis, older allografts were at greater risk for all severe histologic features and decreased graft survival as compared with younger allografts (P< or =0.02 for all outcomes). Analysis of donor age as a dichotomous variable showed that donors greater than 60 yr were at high risk for deleterious histologic outcomes and graft failure. An age cutoff of 60 yr showed a sensitivity of 94% and specificity of 67% for worse graft survival by receiver operating characteristics curve.

CONCLUSIONS

Advanced donor age is associated with more aggressive recurrent HCV and early allograft failure in HCV-positive liver transplant recipients. Consideration of donor age is important for decisions regarding patient selection, antiviral therapy, and organ allocation.

Long-term outcome of deceased donor renal transplants correlates with the 30-day creatinine reduction ratio

A simplified model to correlate early allograft function with long-term allograft survival in recipients of deceased donor renal transplants (DDRT) remains challenging. We propose here a novel approach, using the change from the pretransplant creatinine to the 30-day posttransplant creatinine. The outcomes of 153 consecutive DDRT performed at our center between January 1998 and March 2001 were reviewed. The percentage change in creatinine from the pretransplant to 1 month posttransplant, termed here, the creatinine reduction ratio (CRR), was calculated as follows: (pretransplant creatinine-creatinine at 1 month)/pretransplant creatinine *100%. Patients were divided as follows: group 1 CRR>or=67% and group 2<67%. Group 1 had a graft survival at 1 and 5 years of 100% and 89.1% versus 88% and 69.1% for group 2 (log-rank p=0.0008). The risk ratio for graft loss during the follow-up period was four times lower for the patients on group 1. Using the Cox hazards model to compare CRR>or=67% with determinants of long-term outcome, the risk ratio of graft loss during the observational period was 0.26 (p=0.001). The creatinine reduction ratio, when stratified by a level of >or=67% has a strong correlation with superior long-term allograft survival in recipients of DDRT.

Positive Serum Cryoglobulin Is Associated with Worse Outcome after Liver Transplantation for Chronic Hepatitis C

BACKGROUND

Recurrent hepatitis C virus (HCV) infection in patients after liver transplantation is an important clinical problem. Because serum cryoglobulins (CG) are known to be associated with an increased incidence of cirrhosis in nontransplant patients, the authors tested the hypothesis that CG would also predict aggressive recurrent HCV in patients after liver transplantation.

METHODS

Using a longitudinal database, the outcomes of 105 allografts transplanted into 97 HCV-positive patients from 1991 through 2002 were analyzed on the basis of CG status using a retrospective cohort design. Fifty-nine CG-negative and 38 CG-positive patients were identified. Histologic outcomes and graft survival were analyzed using Kaplan-Meier estimates and Cox univariate and multivariate analyses. Both overall survival and HCV-specific survival (non-HVC-related deaths and graft losses censored) were analyzed.

RESULTS

By Kaplan-Meier estimates, CG-positive patients showed earlier graft failure with decreased time to severe histologic activity and fibrosis as compared with CG-negative patients (P<0.05 for all outcomes). By univariate analysis, CG-positive patients had significantly higher risk ratios for shortened HCV-specific graft survival, severe activity-free survival, and severe fibrosis-free survival as compared with CG-negative patients (P<0.05 for all outcomes). In the multivariate model, CG was an independent predictor for severe activity-free, severe fibrosis-free, and HCV-specific graft survival (P<0.05 for all outcomes).

CONCLUSIONS

CG-positivity is associated with severe recurrent HCV disease in liver transplant recipients.

Effects of antihypertensive therapy on serum lipids

PURPOSE

To compare and contrast the effects of antihypertensive agents on serum lipids and blood pressure in different patient populations.

DATA SOURCES

A MEDLINE search and bibliographies from recent comprehensive reviews were used to identify trials that provided sufficient data to calculate the change in one or more serum lipid values measured before and after antihypertensive therapy.

STUDY SELECTION

474 controlled and uncontrolled clinical trials investigated the effects of 85 antihypertensive agents on lipids and blood pressure in more than 65,000 patients.

DATA EXTRACTION

Data on triglyceride and total, low-density lipoprotein (LDL), and high-density lipoprotein (HDL) cholesterol levels; blood pressure; patient characteristics; and study design.

DATA SYNTHESIS

Differences in the effects of agents, adjusted for differences in patient populations and study design, were examined using multiple linear regression analysis that was weighted by study quality and inverse variance. Diuretics caused relative increases in cholesterol levels (regression coefficient = 0.13 mmol/L; 95% CI, 0.09 to 0.18 mmol/L) that were greater with higher doses (additional effect of high dose, 0.12 mmol/L; CI, 0.04 to 0.20 mmol/L) and were worse in blacks than in nonblacks (additional effect in blacks, 0.13 mmol/L; CI, 0.01 to 0.26 mmol/L). Beta-blockers caused increases in triglyceride levels (0.35 mmol/L; CI, 0.31 to 0.39 mmol/L) that were substantially smaller for agents with intrinsic sympathomimetic activity (amelioration of beta-blocker increase, -0.21 mmol/L; CI, -0.27 to -0.16 mmol/L). When combined with cardioselectivity, beta-blockers with intrinsic sympathomimetic activity favorably affected lipids and reduced both total (-0.14 mmol/L; CI, -0.24 to -0.04 mmol/L) and LDL cholesterol levels (-0.17 mmol/L; CI, -0.28 to -0.07 mmol/L). alpha-Blockers beneficially affected total cholesterol (-0.23 mmol/L; CI, -0.28 to -0.18 mmol/L), LDL cholesterol (-0.20 mmol/L; CI, -0.25 to 0.15 mmol/L), triglycerides (-0.07 mmol/L; CI, -0.11 to -0.03 mmol/L), and, in younger persons, HDL cholesterol (0.02 mmol/L; 0.01 to 0.04 mmol/L). Converting enzyme inhibitors reduced triglycerides (-0.07 mmol/L; CI, -0.12 to -0.02 mmol/L), and, in patients with diabetes, total cholesterol (-0.22 mmol/L; CI, -0.34 to -0.10 mmol/L). Vasodilators reduced total (-0.22 mmol/l; CI, -0.30 to -0.10 mmol/L) and LDL cholesterol (-0.22 mmol/L; CI, -0.29 to -0.11 mmol/L) and increased HDL cholesterol (0.06 mmol/L; CI, 0.02 to 0.09 mmol/L).

CONCLUSION

With the exception of calcium antagonists, nearly all antihypertensive agents affect serum lipids. These effects differ among patient populations.

Effect of antihypertensive therapy on the kidney in patients with diabetes: a meta-regression analysis

OBJECTIVE

To assess the relative effect of different antihypertensive agents on proteinuria and renal function in patients with diabetes.

DATA SOURCES

We used MEDLINE and bibliographies in recent articles to identify studies of the effects of antihypertensive agents on renal function in patients with diabetes.

STUDY SELECTION

We selected 100 controlled and uncontrolled studies that provided data on renal function, proteinuria, or both, before and after treatment with an antihypertensive agent.

DATA EXTRACTION

Data on blood pressure, renal function, proteinuria, patient characteristics (for example, age, sex, and type of diabetes), and study design (for example, random allocation and the use of a placebo) were extracted from selected studies.

DATA SYNTHESIS

Multiple linear regression analysis indicated that angiotensin-converting enzyme (ACE) inhibitors decreased proteinuria independent of changes in blood pressure, treatment duration, and the type of diabetes or stage of nephropathy, as well as study design (P < 0.0001). Reductions in proteinuria from other antihypertensive agents could be entirely explained by changes in blood pressure. Blood pressure reduction in itself was associated with a relative increase in glomerular filtration rate (regression coefficient [+/- SE], 3.70 +/- .92 mL/min for each reduction of 10 mm Hg in mean arterial pressure; P = 0.0002); however, compared with other agents, ACE inhibitors had an additional favorable effect on glomerular filtration rate that was independent of blood pressure changes (3.41 +/- 1.71 mL/min; P = 0.05).

CONCLUSION

Angiotensin-converting enzyme inhibitors can decrease proteinuria and preserve glomerular filtration rate in patients with diabetes. These effects occur independent of changes in systemic blood pressure.

Patients with a low income have reduced renal allograft survival

The impact of socioeconomic factors on long-term outcome after renal transplantation is unknown. We examined the effects of family income among 202 patients transplanted between 1976 and 1982 who had an allograft that functioned for at least 1 year. Compared with patients with an adequate income, recipients of medical assistance at the time of transplantation were more likely to return to dialysis after 1 year (16/45 [36%] v 26/157 [17%], P less than 0.01), or after 5 years of graft function (10/38 [26%] v 12/116 [10%], P less than 0.01). Patients who complied with fewer than 85% of visits during the first 2 years were also more likely to return to dialysis after 1 year (17/49 [35%] v 25/153 [16%], P less than 0.01), or after 5 years (8/31 [26%] v 14/123 [11%], P less than 0.05) than were more compliant patients. However, noncompliance was not different in patients with and without a low income (37/157 [24%] v 12/45 [27%], P greater than 0.05). The relative risk for returning to dialysis after 5 years was 2.4 (P less than 0.05) for low income and 3.0 (P less than 0.05) for less than 85% compliance using a Cox proportional hazards model. These effects were independent of prior transplantation, mismatches, pre-formed antibodies, delayed graft function, age, sex, diabetes, alcohol or drug abuse, education, race, distance from the transplant center, and living in an urban environment (relative risk = 2.5, P less than 0.05). Neither income nor compliance could be linked to death.(ABSTRACT TRUNCATED AT 250 WORDS)

Adjunctive therapy with intravenous human immunoglobulin G improves survival of patients with acute renal failure

The objective of this prospective, randomized, double-blind, placebo-controlled clinical trial was to evaluate the efficacy of adjunctive therapy with iv human immunoglobulin G in reducing the morbidity and mortality associated with acute renal failure. Forty patients greater than or equal to 18 yr of age who were identified within 48 h of the onset of acute renal failure and who met the enrollment criteria were enrolled in the study. Thirty-five patients were considered evaluable. Patients were grouped according to the admitting service (medical or surgical/trauma) and were randomized to receive either immunoglobulin G (400 mg/kg body wt) or placebo (normal saline; 8 mL/kg body wt) at study entry and then weekly thereafter for a maximum of 4 doses. The groups were well balanced with respect to demographics, clinical presentation, and severity of illness (APACHE II scores). A significant reduction in mortality at 42 days after study entry was observed. Two of 17 (12%) patients in the immunoglobulin G-treated group compared with 8 of 18 (44%) patients in the placebo-treated group died (P = 0.025). No differences were observed in the frequency of major complications that occurred in association with acute renal failure. However, in patients who manifested infection, greater survival was observed in the immunoglobulin G treatment group. The results suggest that immunoglobulin G administered at the onset of acute renal failure reduced mortality possibly by decreasing the severity of infectious complications associated with the occurrence of of acute renal failure.(ABSTRACT TRUNCATED AT 250 WORDS)

Histopathologic findings associated with a chronic, progressive decline in renal allograft function

The relationship between specific histopathologic findings of chronic rejection (CR) and the clinical course of renal transplant recipients with a chronic progressive decline in allograft function (CPDAF) is unknown. We used one or two hinged regression lines, fitted by least-squares to serial creatinine clearances, to define the onset and clinical course of CPDAF. Biopsies (N = 100) from patients transplanted from 1978 to 1982 were studied retrospectively. Interstitial fibrosis, tubular atrophy, and fibrointimal arterial narrowing were more pronounced in biopsies obtained after, but not before the onset of CPDAF. Interstitial hemorrhage, an infrequent finding in acute vascular rejection, preceded the onset of CPDAF, but the more common histologic findings of acute cellular rejection did not. The severity of histologic features of CR (as reflected by a score combining fibrointimal arterial narrowing, interstitial fibrosis, tubular atrophy, glomerular sclerosis, glomerular mesangial expansion, and glomerular basement membrane reduplication) correlated with the duration of subsequent allograft survival (r = -0.65, P less than 0.001). Glomerular size increased after transplantation, but was not different in patients with or without CPDAF, suggesting that mechanisms related to compensatory hypertrophy did not play a major role in the pathogenesis of CR. In summary, the histologic findings of CR did not predict the onset of CPDAF, did not distinguish whether the pathogenesis was mediated by immune or nonimmune events, but did correlate with the duration of subsequent allograft survival.