Impact of mild to moderate reductions of glomerular filtration rate on coronary artery disease severity

Polygenic association of glomerular filtration rate decline in world trade center responders

BACKGROUND

The factors associated with estimated glomerular filtrate rate (eGFR) decline in low risk adults remain relatively unknown. We hypothesized that a polygenic risk score (PRS) will be associated with eGFR decline.

METHODS

We analyzed genetic data from 1,601 adult participants with European ancestry in the World Trade Center Health Program (baseline age 49.68 ± 8.79 years, 93% male, 23% hypertensive, 7% diabetic and 1% with cardiovascular disease) with ≥ three serial measures of serum creatinine. PRSs were calculated from an aggregation of single nucleotide polymorphisms (SNPs) from a recent, large-scale genome-wide association study (GWAS) of rapid eGFR decline. Generalized linear models were used to evaluate the association of PRS with renal outcomes: baseline eGFR and CKD stage, rate of change in eGFR, stable versus declining eGFR over a 3-5-year observation period. eGFR decline was defined in separate analyses as "clinical" (> -1.0 ml/min/1.73 m2/year) or "empirical" (lower most quartile of eGFR slopes).

RESULTS

The mean baseline eGFR was ~ 86 ml/min/1.73 m2. Subjects with decline in eGFR were more likely to be diabetic. PRS was significantly associated with lower baseline eGFR (B = -0.96, p = 0.002), higher CKD stage (OR = 1.17, p = 0.010), decline in eGFR (OR = 1.14, p = 0.036) relative to stable eGFR, and the lower quartile of eGFR slopes (OR = 1.21, p = 0.008), after adjusting for established risk factors for CKD.

CONCLUSION

Common genetic variants are associated with eGFR decline in middle-aged adults with relatively low comorbidity burdens.

Serum Uric Acid and Coronary Arterial Disease in Predialysis Chronic Kidney Disease Patients

Background–Aim:

Uric acid is considered a marker of high cardiovascular risk. We investigated the association between serum uric acid and coronary arterial disease (CAD) in pre-dialysis chronic kidney disease (CKD) patients.

Methods:

We enrolled 110 subjects on mean age 69.02 ± 14.3 years old. The participants were categorized for both estimated glomerular filtration rate (eGFR) and albuminuria according to criteria 2012 of the Kidney Disease Improving Global Outcomes. Estimated pulse wave velocity (ePWV) was calculated using an equation including the age and mean blood pressure. The CAD prevalence rate was recorded.

Results:

The patients were divided in two groups according to uric acid cutoff point value related to high ePWV. The patients with higher uric acid were older and they had significantly higher systolic blood pressure, pulse pressure, and parathyroid hormone, but significantly lower eGFR and 1,25(OH)2 Vit D3 levels. The association between high uric acid and both high ePWV and CAD occurrence was found to be significant ( x2 = 6.7, P = .008 and x2 = 4.1, P = .03, respectively), although the relationship with albuminuria was found to be nonsignificant. In a built multifactorial model, the low serum uric acid rather than the high was found to be an independent predictor for CAD demonstration entering traditional and specific confounders.

Conclusion:

The low serum uric acid levels were proved to be a significant predictor for CAD accounting potential covariates, even though the high uric acid per se was found to be connected with cardiovascular disease characteristics including arterial stiffness in predialysis CKD patients.

Development and Validation of a Predictive Model for Chronic Kidney Disease After Percutaneous Coronary Intervention in Chinese

AIM

There is no model for predicting the outcomes for coronary heart disease (CHD) patients with chronic kidney disease (CKD) after percutaneous coronary intervention (PCI). To develop and validate a model to predict major adverse cardiovascular events (MACEs) in patients with comorbid CKD and CHD undergoing PCI.

METHODS

We enrolled 1714 consecutive CKD patients who underwent PCI from January 1, 2008 to December 31, 2017. In the development cohort, we used least absolute shrinkage and selection operator regression for data dimension reduction and feature selection. We used multivariable logistic regression analysis to develop the prediction model. Finally, we used an independent cohort to validate the model. The performance of the prediction model was evaluated with respect to discrimination, calibration, and clinical usefulness.

RESULTS

The predictors included a positive family history of CHD, history of revascularization, ST segment changes, anemia, hyponatremia, transradial intervention, the number of diseased vessels, dose of contrast media >200 ml, and coronary collateral circulation. In the validation cohort, the model showed good discrimination (area under the receiver operating characteristic curve, 0.612; 95% confidence interval: 0.560, 0.664) and good calibration (Hosmer-Lemeshow test, P  =  0.444). Decision curve analysis demonstrated that the model was clinically useful.

CONCLUSIONS

We created a nomogram that predicts MACEs after PCI in CHD patients with CKD and may help improve the screening and treatment outcomes.

The Association of Posttraumatic Stress Disorder With Longitudinal Change in Glomerular Filtration Rate in World Trade Center Responders

OBJECTIVE

High levels of psychological distress increase the risk of a wide range of medical diseases. In this study, we investigated the association between posttraumatic stress disorder (PTSD) and kidney disease.

METHODS

World Trade Center (WTC) responders were included if they had two or more measures of estimated glomerular filtration rate (eGFR). The PTSD Checklist (PCL) was used to define no PTSD (PCL < 40), "mild" PTSD (40 ≤ PCL <50), and "severe" PTSD (PCL ≥50). Subtypes of PTSD by symptom clusters were analyzed. Multinomial logistic regression was used to estimate the association of PTSD with two GFR change outcomes (decline or increase) compared with the stable GFR outcome.

RESULTS

In 2266 participants, the mean age was 53.1 years, 8.2% were female, and 89.1% were White. Individuals with PTSD (n = 373; 16.5%) did not differ in mean baseline GFR from individuals without PTSD (89.73 versus 90.56 mL min-1 1.73 m-2; p = .29). During a 2.01-year mean follow-up, a mean GFR decline of -1.51 mL min-1 1.73 m-2 per year was noted. In multivariable-adjusted models, PTSD was associated with GFR decline (adjusted relative risk [aRR] = 1.74 [1.32-2.30], p < .001) compared with stable GFR, with "hyperarousal" symptoms showing the strongest association (aRR =2.11 [1.40-3.19]; p < .001). Dose-response effects were evident when comparing mild with severe PTSD and comparing PTSD with versus without depression. PTSD was also associated with GFR rise (aRR = 1.47 [1.10-1.97], p < .009). The association between PTSD and GFR change was stronger in participants older than 50 years.

CONCLUSIONS

PTSD may be a novel risk factor for exaggerated longitudinal GFR change in young, healthy adults. These findings need to be validated in other cohorts.

Association of Mildly Reduced Kidney Function With Cardiovascular Disease: The Framingham Heart Study

Background Data are limited on the association of mildly reduced estimated glomerular filtration rate (eGFR 60-89 mL/min per 1.73 m²) with cardiovascular disease (CVD) in the community. Methods and Results We evaluated 3066 Framingham Offspring Study participants (55% women, mean age 58 years), without clinical CVD. Using multivariable regression, we related categories of mildly reduced eGFR (80-89, 70-79, or 60-69 versus ≥90 mL/min per 1.73 m² [referent]) to prevalent coronary artery calcium, carotid intima media thickness, and left ventricular hypertrophy, and to circulating concentrations of cardiac stress biomarkers. We related eGFR categories to CVD incidence and to progression to ≥Stage 3 chronic kidney disease (eGFR <60 mL/min per 1.73 m²) using Cox regression. Individuals with eGFR 60-69 mL/min per 1.73 m² (n=320) had higher coronary artery calcium score (odds ratio 1.69; 95% CI 1.02-2.80) compared with the referent group. Individuals with eGFR 60-69 and 70-79 mL/min per 1.73 m² had higher blood growth differentiating factor-15 concentrations (β=0.131 and 0.058 per unit-increase in log-biomarker, respectively). Participants with eGFR 60-69 and 80-89 mL/min per 1.73 m² had higher blood B-type natriuretic peptide concentrations (β=0.119 and 0.116, respectively). On follow-up (median 16 years; 691 incident CVD and 252 chronic kidney disease events), individuals with eGFR 60-69 and 70-79 mL/min per 1.73 m² experienced higher CVD incidence (hazard ratio [HR], 1.40; 95% CI, 1.02-1.93 and 1.45, 95% CI, 1.05-2.00, respectively, versus referent). Participants with eGFR 60-69 mL/min per 1.73 m² experienced higher chronic kidney disease incidence (HR, 2.94; 95% CI, 1.80-4.78 versus referent). Conclusions Individuals with mildly reduced eGFR 60-69 mL/min per 1.73 m² have a higher burden of subclinical atherosclerosis cross-sectionally, and a greater risk of CVD and chronic kidney disease progression prospectively. Additional studies are warranted to confirm our findings.

Long-term outcomes of patients with stable coronary disease and chronic kidney dysfunction: 10-year follow-up of the Medicine, Angioplasty, or Surgery Study II Trial

BACKGROUND

Chronic kidney disease (CKD) is associated with a worse prognosis in patients with stable coronary artery disease (CAD); however, there is limited randomized data on long-term outcomes of CAD therapies in these patients. We evaluated long-term outcomes of CKD patients with CAD who underwent randomized therapy with medical treatment (MT) alone, percutaneous coronary intervention (PCI) or coronary artery bypass graft surgery (CABG).

METHODS

Baseline estimated glomerular filtration rate (eGFR) was obtained in 611 patients randomized to one of three therapeutic strategies in the Medicine, Angioplasty, or Surgery Study II trial. Patients were categorized in preserved renal function and mild or moderate CKD groups depending on their eGFR (≥90, 89-60 and 59-30 mL/min/1.73 m2, respectively). The primary clinical endpoint, a composite of overall death and myocardial infarction, and its individual components were analyzed using proportional hazards regression (Clinical Trial registration information: http://www.controlled-trials.com. Registration number: ISRCTN66068876).

RESULTS

Of 611 patients, 112 (18%) had preserved eGFR, 349 (57%) mild dysfunction and 150 (25%) moderate dysfunction. The primary endpoint occurred in 29.5, 32.4 and 44.7% (P = 0.02) for preserved eGFR, mild CKD and moderate CKD, respectively. Overall mortality incidence was 18.7, 23.8 and 39.3% for preserved eGFR, mild CKD and moderate CKD, respectively (P = 0.001). For preserved eGFR, there was no significant difference in outcomes between therapies. For mild CKD, the primary event rate was 29.4% for PCI, 29.1% for CABG and 41.1% for MT (P = 0.006) [adjusted hazard ratio (HR) = 0.26, 95% confidence interval (CI) 0.07-0.88; P = 0.03 for PCI versus MT; and adjusted HR = 0.48; 95% CI 0.31-0.76; P = 0.002 for CABG versus MT]. We also observed higher mortality rates in the MT group (28.6%) compared with PCI (24.1%) and CABG (19.0%) groups (P = 0.015) among mild CKD subjects (adjusted HR = 0.44, 95% CI 0.25-0.76; P = 0.003 for CABG versus MT; adjusted HR = 0.56, 95% CI 0.07-4.28; P = 0.58 for PCI versus MT). Results were similar with moderate CKD group but did not achieve significance.

CONCLUSIONS

Coronary interventional therapy, both PCI and CABG, is associated with lower rates of events compared with MT in mild CKD patients >10 years of follow-up. More study is needed to confirm these benefits in moderate CKD.

Fast GFR decline and progression to CKD among primary care patients with preserved GFR

BACKGROUND

Fast glomerular filtration rate (GFR) decline is associated with adverse outcomes, but the associated risk factors among patients without chronic kidney disease (CKD) are not well defined.

METHODS

From a primary care registry of 37,796, we identified 2219 (6%) adults with at least three estimated (e)GFR values and a baseline eGFR between 60 and 119 ml/min/1.73 m² during an observation period of 8 years. We defined fast GFR decline as > 5 ml/min/1.73 m² per year. The outcome measure was incident CKD (eGFR < 60 ml/min/1.73 m²). Clinical and demographic characteristics were compared using Chi-square and independent-samples t tests.

RESULTS

Older age, African-American race, unmarried status, hypertension and type 2 diabetes were more common in both fast decliners and those who developed incident CKD (p < 0.0001 to < 0.05). Lower neighborhood socioeconomic status, current smoking and baseline eGFR 90-119 ml/min/1.73 m² were associated with fast decline (p < 0.01), while baseline eGFR 60-74 ml/min/1.73 m² with incident CKD (p < 0.05). In multivariate regression models, among fast decliners with mildly reduced baseline eGFR (60-89 ml/min/1.73 m²), older age was significantly associated with incident CKD [odds ratio (OR) 1.04; 95% CI 1.01-1.08], and among those with normal baseline eGFR (≥ 90-119 ml/min/1.73 m²), type 2 diabetes was significantly associated with incident CKD (OR 3.83; 95% CI 1.35-10.89).

CONCLUSIONS

Among primary care patients without CKD, GFR is checked infrequently. We have identified patients at high risk of progressive CKD, in whom we suggest a closer monitoring of renal function.

The dose-response association between estimated glomerular filtration rate and prognosis of patients with ST-segment elevation myocardial infarction from rural areas of China's Liaoning province

We aimed to investigate the dose-response associations between chronic kidney disease (CKD), and short and long-term cardiovascular outcomes, to characterize these associations by drawing dose-response curves based on a Chinese rural ST-segment elevation myocardial infarction (STEMI) population.In all, 1067 patients with STEMI were consecutively enrolled from 12 secondary hospitals of China's Liaoning province (from June 2009 to June 2010 and January 2015 to December 2015). The follow-up was regularly performed by telephone. Patients were grouped by estimated glomerular filter rate (eGFR): normal, eGFR ≥90 mL/min/1.73 m; mild CKD, 60 to 90 mL/min/1.73 m; CKD, <60 mL/min/1.73 m. Adjusted logistic or Cox regression models were employed to compare short and long-term cardiovascular outcomes across different eGFR groups. Dose-response curves were plotted using restricted cubic spline functions.About 18.46% of the STEMI patients had CKD. Patients with CKD were more likely to suffer from other comorbidities, but less likely to receive evidence-based therapies. CKD was independently associated with in-hospital mortality and major adverse cardiac events (MACE) as compared with patients with normal renal function (for in-hospital mortality, adjusted odds ratio [OR] 2.39, 95% confidence interval [CI] 1.18-4.85, P = .02; for in-hospital MACE, adjusted OR 2.01, 95% CI 1.09-3.70, P < .01). Likewise, CKD was significantly associated with long-term mortality as well (CKD vs normal, adjusted hazard ratio 2.55, 95% CI 1.17-5.57, P = .02). The dose-response associations between eGFR, and short and long-term cardiovascular outcomes were found to be linear (all with P values for nonlinear associations >.05).CKD is an independent predictor of worse in-hospital and long-term clinical outcomes. The assessment of eGFR is essential to enable risk stratification, tailored therapy, and early and aggressive management.

Uric acid, renal function and risk of hypoglycaemia in Chinese type 2 diabetes patients

BACKGROUND

This study aimed to explore independent associations between serum uric acid and hypoglycaemia, and whether mildly increased serum uric acid exacerbated the association between mild decline in estimated glomerular filtration rate (eGFR) and hypoglycaemia.

METHODS

A cross-sectional survey of 6713 inpatients with type 2 diabetes and eGFR ≥60 mL/min/1.73 m² and admitted to 81 tertiary care hospitals in China was conducted. Self-reported asymptotic hypoglycaemia with plasma glucose ≤3.9 mmol/L, hypoglycaemia episodes with symptoms in 1 month or hypoglycaemia that needed assistance from other people in 3 months before hospitalization was used to define hypoglycaemia. Binary logistic regression was used to estimate odds ratios of serum uric acid for hypoglycaemia. Three measures, that is, relative excess risk due to interaction (RERI), attributable proportion due to interaction and synergy index (S) were used to estimate the effect of mildly decreased eGFR on the association of serum uric acid with hypoglycaemia.

RESULTS

Serum uric acid was associated with hypoglycaemia in an ordinal manner (P for trend <0.01) with an odds ratio of top quartile versus the lowest quartile up to 3.03 (95% confidence interval: 2.13-4.32). The odds ratio of serum uric acid levels ≥ versus <283 µmol/L (i.e. the median) was 1.98 (95% confidence interval:1.58-2.48). Serum uric acid levels ≥ versus <283 µmol/L greatly enhanced the association between mild decline in eGFR (eGFR < 90 mL/min/1.73 m² ) and hypoglycaemia from 0.94 (0.36-2.43) to 3.90 (2.55-5.95), with a significant additive interaction (P < 0.05 for RERI, AP and S).

CONCLUSIONS

Mildly increased serum uric acid was associated with increased risk of hypoglycaemia and enhanced the association between mildly decreased eGFR and hypoglycaemia in type 2 diabetes. Copyright © 2016 John Wiley & Sons, Ltd.

Renal Impairment and Cardiovascular Disease in HIV-Positive Individuals: The D:A:D Study

BACKGROUND

While the association between renal impairment and cardiovascular disease (CVD) is well established in the general population, the association remains poorly understood in human immunodeficiency virus (HIV)-positive individuals.

METHODS

Individuals with ≥2 estimated glomerular filtration rate (eGFR) measurements after 1 February 2004 were followed until CVD, death, last visit plus 6 months, or 1 February 2015. CVD was defined as the occurrence of centrally validated myocardial infarction, stroke, invasive cardiovascular procedures, or sudden cardiac death.

RESULTS

During a median follow-up duration of 8.0 years (interquartile range, 5.4-8.9 years) 1357 of 35 357 individuals developed CVD (incidence rate, 5.2 cases/1000 person-years [95% confidence interval {CI}, 5.0-5.5]). Confirmed baseline eGFR and CVD were closely related with 1.8% of individuals (95% CI, 1.6%-2.0%) with an eGFR > 90 mL/minute/1.73 m(2) estimated to develop CVD at 5 years, increasing to 21.1% (95% CI, 6.6%-35.6%) among those with an eGFR ≤ 30 mL/minute/1.73 m(2) The strong univariate relationship between low current eGFR and CVD was primarily explained by increasing age in adjusted analyses, although all eGFRs ≤ 80 mL/minute/1.73 m(2) remained associated with 30%-40% increased CVD rates, and particularly high CVD rates among individuals with an eGFR ≤ 30 mL/minute/1.73 m(2) (incidence rate ratio, 3.08 [95% CI, 2.04-4.65]).

CONCLUSIONS

Among HIV-positive individuals in a large contemporary cohort, a strong relation between confirmed impaired eGFR and CVD was observed. This finding highlights the need for renal preventive measures and intensified monitoring for emerging CVD, particularly in older individuals with continuously low eGFRs.

Clinical impact of coexisting retinopathy and vascular calcification on chronic kidney disease progression and cardiovascular events

BACKGROUND AND AIMS

Retinopathy and vascular calcification (VC) are representative markers of microvascular and macrovascular dysfunction in patients with chronic kidney disease (CKD). However, their relationship and combined effects on clinical outcomes remain undetermined.

METHODS AND RESULTS

We included 523 patients with nondialysis-dependent CKD stage 3-5 who had been examined with fundus photography for diabetic or hypertensive retinopathy. Simple radiographs were analyzed for the presence of VC. The clinical significance of VC of the abdominal aorta and iliofemoral artery (apVC) and retinopathy was evaluated in terms of the rate of renal function decline and composite of any cardiovascular event or death. CKD patients with retinopathy showed higher prevalence of apVC than those without retinopathy (25.6% vs. 12.5%, P < 0.001).The presence of retinopathy was independently associated with apVC (OR 2.13, 95% CI 1.31, 3.49). In multivariate analysis, compared with subjects with neither apVC nor retinopathy, the coexistence of both apVC and retinopathy were independently associated with rapid renal function decline (β = -1.51; 95% CI -2.40, -0.61), whereas apVC or retinopathy alone were not. Compared with subjects with neither apVC nor retinopathy, the HRs for composite end points were 1.05 (95% CI 0.48, 2.27), 1.79 (95% CI 1.14, 2.80), and 2.07 (95% CI 1.17, 3.67) for patients with apVC only, those with retinopathy only, and those with both apVC and retinopathy, respectively.

CONCLUSION

The coexistence of VC and retinopathy was independently associated with CKD progression and cardiovascular events or deaths, and its combined effect was stronger than any separate condition.

Does a Reduction in the Glomerular Filtration Rate Increase the Overall Severity of Coronary Artery Stenosis?

OBJECTIVE

Chronic kidney disease is a risk factor of coronary events, however, its impact on coronary artery stenosis has not yet been clarified with the use of a large database. We examined the association between a reduced glomerular filtration rate (GFR) and the overall severity of coronary stenosis.

METHODS

We enrolled 1,150 patients [mean age, 68±12 (SD) years; 66.6% men] who consecutively underwent coronary angiography for suspected stable angina pectoris. The overall severity of stenosis in the coronary arteries was assessed by the Gensini score (GS), and its logarithmic values (log-GS) were used for statistical analyses since the GS does not follow a normal distribution.

RESULTS

The log-GS was significantly larger in men than in women (2.5±1.5 vs. 1.9±1.7), while the estimated GFR (eGFR) and comorbidities were comparable between both sexes. A multivariate regression analysis indicated that age, smoking, eGFR, HDL-cholesterol and HbA1c were independent explanatory variables of the log-GS in men, although the eGFR explained only 1.2% of the log-GS variation. In women, the eGFR was not included in the significant explanatory variables shown by the multivariate analysis. However, the sex difference in the regression for the eGFR-log-GS relationship was not statistically significant.

CONCLUSION

A reduced eGFR is a significant, but minor, determinant of the overall severity of coronary artery stenosis in men and potentially women.

Fasting blood glucose, but not 2-h postload blood glucose or HbA1c, is associated with mild decline in estimated glomerular filtration rate in healthy Chinese

BACKGROUND

The association of blood glucose [including fasting blood glucose (FBG), 2-h postload blood glucose, and glycated hemoglobin (HbA1c)] with the risk of a mild decline in the estimated glomerular filtration rate (eGFR) in healthy subjects was unclear. The aim of the study was to investigate this association in middle-aged and elderly healthy Chinese.

METHODS

The study included 1,112 healthy Chinese who were ≥40 years old, and all the subjects were divided into two groups based on FBG value of 5.6 mmol/L. A mildly reduced eGFR was defined as 60-90 mL/min/1.73 m2. Multiple linear or logistic regression analysis was used to estimate the association of blood glucose with eGFR and the risk of a mildly reduced eGFR, respectively. A generalized additive model was used to explore a possible nonlinear relationship between FBG and eGFR.

RESULTS

FBG was significantly associated with decreased eGFR and increased risk of a mildly reduced eGFR independent of age, gender, body mass index, waist circumference, systolic blood pressure (BP), diastolic BP, triglyceride, high-density lipoprotein cholesterol, fasting insulin, smoking, and drinking. Additionally, FBG and eGFR showed a nonlinear association (P<0.001). Interestingly, the group with FBG≥5.6 mmol/L significantly increased the risk of a mildly reduced eGFR (OR 2.06, P=0.001) after multivariable adjustment.

CONCLUSIONS

FBG is closely associated with decreased eGFR and increased risk of a mildly reduced eGFR. The ADA criteria using FBG=5.6 mmol/L instead of 6.1 mmol/L as cutoff point to define prediabetes are more suitable for the prevention of diabetes and related kidney disease.

Triglyceride levels are closely associated with mild declines in estimated glomerular filtration rates in middle-aged and elderly Chinese with normal serum lipid levels

OBJECTIVE

To investigate the relationship between lipid profiles [including total cholesterol (TC), triglyceride (TG), low-density lipoprotein cholesterol (LDL-C) and high-density lipoprotein cholesterol (HDL-C)] and a mild decline in the estimated glomerular filtration rate (eGFR) in subjects with normal serum lipid levels.

DESIGN AND METHODS

In this study, we included 2647 participants who were ≥ 40 years old and had normal serum lipid levels. The Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation was used to estimate the GFR. A mildly reduced eGFR was defined as 60-90 mL/min/1.73 m(2). First, multiple linear regression analysis was used to estimate the association of lipid profiles with the eGFR. Then, the levels of each lipid component were divided into four groups, using the 25th, 50th and 75th percentiles as cut-off points. Finally, multiple logistic regression analysis was used to investigate the association of different lipid components with the risk of mildly reduced eGFR.

RESULTS

In the group with a mildly reduced eGFR, TG and LDL-C levels were significantly increased, but HDL-C levels were significantly decreased. After adjusting for age, gender, body mass index (BMI), systolic blood pressure (SBP), glycated hemoglobin (HbA1c), smoking and drinking, only TC and TG were independently related to the eGFR. Additionally, only TG showed a linear relationship with an increased risk of a mildly reduced eGFR, with the highest quartile group (TG: 108-150 mg/dl [1.22-1.70 mmol/L]) having a significantly increased risk after adjusting for the above factors.

CONCLUSIONS

Triglyceride levels are closely associated with a mildly reduced eGFR in subjects with normal serum lipid levels. Dyslipidemia with lower TG levels could be used as new diagnostic criteria for subjects with mildly reduced renal function.

Metabolic abnormalities, but not obesity, contribute to the mildly reduced eGFR in middle-aged and elderly Chinese

BACKGROUND

The role of obesity as a determinant of kidney dysfunction has not reached an agreement and the underlying reason may be due to the heterogeneity of obese phenotypes. The aim of the study was to explore the associations of different obese phenotypes with the change of estimated glomerular filtration rate (eGFR) and the roles of obesity and metabolic abnormalities in this association.

METHODS

eGFR was calculated in 8,586 participants (≥ 40 years old). eGFR 60-90 mL/min/1.73 m(2) was defined as the mildly reduced eGFR. Multiple logistic regression analysis was used to determine odds ratios (ORs) for mildly reduced eGFR in the metabolically healthy obese (MHO), metabolically abnormal non-obese (MANO) and metabolically abnormal obese (MAO) groups, using the metabolically healthy non-obese (MHNO) subjects as the reference group. Meanwhile, the associations of body mass index (BMI), waist circumference (WC) and metabolic abnormalities (including hypertension, hyperglycemia and dyslipidemia) with the risk of mildly reduced eGFR were also investigated.

RESULTS

The proportion of MHNO, MHO, MANO and MAO subjects was 8.3, 17.1, 10.1 and 64.5 %, respectively. Increased ORs were observed in MANO (OR 1.51, P = 0.014) and MAO (OR 1.47, P = 0.015) groups, after adjusting for age, gender, smoking, drinking, BMI and WC. When further adjusting for metabolic abnormalities, MANO (OR 1.24, P = 0.247) and MAO (OR 1.17, P = 0.366) subjects would not present increased risk of mildly reduced eGFR any more. Oppositely, fasting insulin (OR 1.03, P < 0.001), hyperglycemia (OR 1.25, P = 0.002) and dyslipidemia (OR 1.25, P = 0.002), but not hypertension, BMI and WC, significantly increased the risk of mildly reduced eGFR.

CONCLUSIONS

Metabolic abnormalities, but not simple obesity, may contribute to the mildly reduced eGFR in middle-aged and elderly Chinese.