Clinical and pathological analysis of renal damage in elderly patients with type 2 diabetes mellitus

Guideline for the Management of Diabetes Mellitus in the Elderly in China (2024 Edition)

With the deepening of aging in China, the prevalence of diabetes in older people has increased noticeably, and standardized diabetes management is critical for improving clinical outcomes of diabetes in older people. In 2021, the National Center of Gerontology, Chinese Society of Geriatrics, and Diabetes Professional Committee of Chinese Aging Well Association organized experts to write the first guideline for diabetes diagnosis and treatment in older people in China, the Guideline for the Management of Diabetes Mellitus in the Elderly in China (2021 Edition). The guideline emphasizes that older patients with diabetes are a highly heterogeneous group requiring comprehensive assessment and stratified and individualized management strategies. The guideline proposes simple treatments and de-intensified treatment strategies for older patients with diabetes. This edition of the guideline provides clinicians with practical and operable clinical guidance, thus greatly contributing to the comprehensive and full-cycle standardized management of older patients with diabetes in China and promoting the extensive development of clinical and basic research on diabetes in older people and related fields. In the past 3 years, evidence-based medicine for older patients with diabetes and related fields has further advanced, and new treatment concepts, drugs, and technologies have been developed. The guideline editorial committee promptly updated the first edition of the guideline and compiled the Guideline for the Management of Diabetes Mellitus in the Elderly in China (2024 Edition). More precise management paths for older patients with diabetes are proposed, for achieving continued standardization of the management of older Chinese patients with diabetes and improving their clinical outcomes.

Diagnostic value of serum cystatin C for diabetic nephropathy: a meta-analysis

BACKGROUND

Although dozens of studies have investigated the relationship between the content of serum cystatin C (Cys-C) and diabetic nephropathy (DN), the results are still controversial. Hence, This study aims to explore the accuracy of serum Cys-C for diagnosing DN by meta-analysis.

METHODS

The studies about serum Cys-C diagnosing DN were searched from six online databases from inception to September 22, 2020. The data were processed by Stata 15.0 statistic software. The corresponding diagnostic effect sizes, such as sensitivity and specificity, were obtained. We drew a summary receiver operating characteristic (SROC) curve. We assess the risk of literature bias was following the QUADAS-2 guidelines.

RESULTS

Twenty-six published studies were identified. The results showed a pooled sensitivity of 0.86 (95% confidence interval (CI): 0.82-0.90), specificity of 0.89 (95%CI: 0.85-0.92), positive likelihood ratio of 7.59 (95%CI: 5.66-10.19), negative likelihood ratio of 0.16 (95%CI: 0.12-0.21), and diagnostic odds ratio of 48.03 (95%CI: 30.64-75.29). The area under the SROC curve was given a value of 0.94 (95%CI: 0.91-0.96).

CONCLUSION

Serum cystatin C has an excellent diagnostic value with good sensitivity and specificity for diabetic nephropathy.

Clinicopathologic features and prognostic factors in older patients with biopsy-proven diabetic nephropathy

PURPOSE

The older population has increased sharply in China. However, renal clinical and histopathological data in this population are lacking. This study investigated the clinicopathologic features and the related risk factors for long-term renal survival in older patients with diabetic nephropathy (DN).

METHODS

In this retrospective observational study, 74 older patients (≥ 60 years old) with type 2 diabetes mellitus and biopsy-proven DN from 2007 to 2019 were included. Clinical data were extracted from electronic records. Renal biopsy specimens were semiquantitatively evaluated using the Renal Pathology Society (RPS) classification system. Cox proportional hazard analysis was used to estimate hazard ratios (HRs) for progression to end-stage renal disease (ESRD).

RESULTS

During the median follow-up period of 22 months, 24 (32%) older patients progressed to ESRD. Older patients who progressed to ESRD had poorer renal function, lower hemoglobin and albumin concentrations, more severe glomerular lesions, and higher percentages of Kimmelstiel-Wilson lesions than those who did not progress to ESRD. After adjusting for age, sex, baseline renal function, and pathological parameters, multivariate Cox proportional hazard analysis showed that RPS glomerular classification (HR 2.49, 95% confidence interval [CI] 1.03-6.04), estimated glomerular filtration rate (eGFR) (HR 0.76, 95% CI 0.58-0.99), and proteinuria (HR 3.85, 95% CI 1.44-10.27) were independent risk factors for progression to ESRD.

CONCLUSION

Lower eGFR, heavier proteinuria, and more severe RPS glomerular lesions were associated with ESRD in older patients with type 2 diabetes mellitus and DN.

Potential Role of the Renal Arterial Resistance Index in the Differential Diagnosis of Diabetic Kidney Disease

AIMS

To investigate the potential role of renal arterial resistance index (RI) in the differential diagnosis between diabetic kidney disease (DKD) and non-diabetic kidney disease (NDKD) and establish a better-quantified differential diagnostic model.

MATERIALS AND METHODS

We consecutively reviewed 469 type 2 diabetes patients who underwent renal biopsy in our center. According to the renal biopsy results, eligible patients were classified into the DKD group and the NDKD group. The diagnostic significance of RI was evaluated by receiver operating characteristic (ROC) curve analysis. Logistic regression analysis was used to search for independent risk factors associated with DKD. Then a novel diagnostic model was established using multivariate logistic regression analysis.

RESULTS

A total of 332 DKD and 137 NDKD patients were enrolled for analysis. RI was significantly higher in the DKD group compared with those in the NDKD group (0.70 vs. 0.63, p< 0.001). The optimum cutoff value of RI for predicting DKD was 0.66 with sensitivity (69.2%) and specificity (80.9%). Diabetic retinopathy, diabetes duration ≥ 60 months, HbA1c ≥ 7.0(%), RI ≥ 0.66, and body mass index showed statistical significance in the multivariate logistic regression analysis. Then, we constructed a new diagnostic model based on these results. And the validation tests indicated that the new model had good sensitivity (81.5%) and specificity (78.6%).

CONCLUSIONS

RI has a potential role in discriminating DKD from NDKD. The RI-based predicting model can be helpful for differential diagnosis of DKD and NDKD.

Clinicopathological Features of Nondiabetic Renal Diseases from Different Age Groups: An Observational Cross-sectional Study

Background

Diabetes mellitus (DM) has become the leading cause of chronic kidney disease (CKD). Nondiabetic renal diseases (NDRDs) have different clinicopathological features and prognosis from those of diabetic nephropathy. Our study sought to analyze the clinical and pathological features of NDRDs, in different age groups through a cross-sectional study.

Methods

All patients with type 2 DM at our center who underwent renal biopsy between March 1997 and March 2017 were screened and divided into three groups by age: Group 1 (youth group), 18-44 years old; Group 2 (middle-aged group), 45-59 years old; and Group 3 (elderly group), ≥60 years old. We analyzed the clinicopathological data and risk factors by univariate and multivariate logistic regression for NDRD of the patients to identify the features of NDRD in different age groups.

Results

We included 982 patients in the final analysis. Patients with NDRD accounted for 64.4% of all patients. IgA nephropathy (IgAN) was the most common pathological pattern in young patients with NDRD, accounting for 26.3%. In the middle-aged group, the two most common pathological patterns were IgAN and membranous nephropathy. Membranous nephropathy was the most common pathological pattern in elderly patients with NDRD, accounting for 29.3%. Consistent with pathological features, glomerular hematuria is a risk factor for NDRD in Group 1 (odds ratio [OR], 26.514; 95% confidence interval [CI], 2.503-280.910; P = 0.006). On the other hand, rapidly increasing proteinuria or nephrotic syndrome is a risk factor for NDRD in Group 2 (OR, 5.921; 95% CI, 2.061-17.013; P = 0.001) and Group 3 (OR, 90.409; 95% CI, 6.198-1318.826; P = 0.001).

Conclusions

This single-center study showed that the proportion and composition of NDRD differ among different age groups. Consistent with pathological features, some clinical indices such as hematuria and proteinuria showed different features among different age groups.

Contribution of the clinical information to the accuracy of the minimally invasive and the complete diagnostic autopsy

Although autopsy diagnosis includes routinely, a thorough evaluation of all available pathological results and also of any available clinical data, the contribution of this clinical information to the diagnostic yield of the autopsy has not been analyzed. We aimed to determine to which degree the use of clinical data improves the diagnostic accuracy of the complete diagnostic autopsy (CDA) and the minimally invasive autopsy (MIA), a simplified pathological postmortem procedure designed for low-income sites. A total of 264 coupled MIA and CDA procedures (112 adults, 57 maternal deaths, 54 children, and 41 neonates) were performed at the Maputo Hospital, Mozambique. We compared the diagnoses obtained by the MIA blind to clinical data (MIAb), the MIA adding the clinical information (MIAc), and the CDA blind to clinical information (CDAb), with the results of the gold standard, the CDA with clinical data, by comparing the International Classification of Diseases, Tenth Revision codes and the main diagnostic classes obtained with each evaluation strategy (MIAb, MIAc, CDAb, CDAc). The clinical data increased diagnostic coincidence to the MIAb with the gold standard in 30 (11%) of 264 cases and modified the CDAb diagnosis in 20 (8%) of 264 cases. The increase in concordance between MIAb and MIAc with the gold standard was significant in neonatal deaths (κ increasing from 0.404 to 0.618, P = .0271), adult deaths (κ increasing from 0.732 to 0.813, P = .0221), and maternal deaths (κ increasing from 0.485 to 0.836, 0.;P < .0001). In conclusion, the use of clinical information increases the precision of MIA and CDA and may strengthen the performance of the MIA in resource-limited settings.

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The addition of clinical data increases the diagnostic accuracy of the minimally invasive autopsy (MIA) and complete diagnostic autopsy in 12% and 8% of the cases, respectively.

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The increase in concordance from MIA blind to clinical data to MIA enhanced with clinical data was significant in neonatal, adult, and maternal deaths and was also evident in children, although it did not reach statistical significance.

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The use of clinical data may improve the diagnostic precision of the MIA in resource-limited settings.

The modern spectrum of biopsy-proven renal disease in Chinese diabetic patients-a retrospective descriptive study

Background

Renal biopsies performed in diabetic patients are increasing and becoming more complex. Comprehensive data on modern spectrum of biopsy-proven renal disease in Chinese diabetic patients are lacking.

Methods

In a nationwide renal biopsy survey including 71,151 native biopsies from 2004 to 2014, diabetic patients were identified according to the clinical diagnosis from referral records. The clinical data were extracted from referral records and pathological reports.

Results

A total of 1,604 diabetic patients, including 61 patients with T1DM, were analyzed in this study. The median age is 51.39 ± 11.37 years. Male patients accounted for 58% of the population. We found that only 44.7% of diabetic patients had the isolated pathological diagnosis of diabetic nephropathy (DN), while 49.1% had non-diabetic renal disease (NDRD) alone, and 6.2% had NDRD superimposed on DN. Nephrotic syndrome (n = 824, 51.4%) was the most common clinical indication for renal biopsy. Among 887 patients with NDRD, membranous nephropathy (n = 357) was the leading diagnosis, followed by IgA nephropathy (n = 179). Hypertensive renal disease (n = 32), tubulointerstitial nephropathy (n = 27) and acute tubular necrosis (n = 16) accounted for 3.5%, 2.9%, 1.7% of the NDRD cases respectively. Nearly a half (49.2%) of patients with T1DM had NDRD.

Discussion

Over 55% diabetic patients with kidney disease were diagnosed as non-diabetic renal disease, among which MN and IgAN were the most common two pathological types.

Validity of a Minimally Invasive Autopsy for Cause of Death Determination in Adults in Mozambique: An Observational Study

BACKGROUND

There is an urgent need to identify tools able to provide reliable information on the cause of death in low-income regions, since current methods (verbal autopsy, clinical records, and complete autopsies) are either inaccurate, not feasible, or poorly accepted. We aimed to compare the performance of a standardized minimally invasive autopsy (MIA) approach with that of the gold standard, the complete diagnostic autopsy (CDA), in a series of adults who died at Maputo Central Hospital in Mozambique.

METHODS AND FINDINGS

In this observational study, coupled MIAs and CDAs were performed in 112 deceased patients. The MIA analyses were done blindly, without knowledge of the clinical data or the results of the CDA. We compared the MIA diagnosis with the CDA diagnosis of cause of death. CDA diagnoses comprised infectious diseases (80; 71.4%), malignant tumors (16; 14.3%), and other diseases, including non-infectious cardiovascular, gastrointestinal, kidney, and lung diseases (16; 14.3%). A MIA diagnosis was obtained in 100/112 (89.2%) cases. The overall concordance between the MIA diagnosis and CDA diagnosis was 75.9% (85/112). The concordance was higher for infectious diseases and malignant tumors (63/80 [78.8%] and 13/16 [81.3%], respectively) than for other diseases (9/16; 56.2%). The specific microorganisms causing death were identified in the MIA in 62/74 (83.8%) of the infectious disease deaths with a recognized cause. The main limitation of the analysis is that both the MIA and the CDA include some degree of expert subjective interpretation.

CONCLUSIONS

A simple MIA procedure can identify the cause of death in many adult deaths in Mozambique. This tool could have a major role in improving the understanding and surveillance of causes of death in areas where infectious diseases are a common cause of mortality.

Clinicopathological characteristics of non-diabetic renal disease in patients with type 2 diabetes mellitus in a northeastern Chinese medical center: a retrospective analysis of 273 cases

OBJECTIVE

To investigate the clinical and histopathological features of non-diabetic renal disease (NDRD) superimposed on diabetic nephropathy (DN) in northeastern Chinese patients with type 2 diabetes mellitus (T2D), and compare the changes with those of pure DN and isolated NDRD.

METHODS

Single-center retrospective analysis based on medical records of 273 patients (172 men, mean age: 51.1 ± 12.4 years) with T2D who underwent renal biopsy between February 2000 and October 2015. All patients were diagnosed as cases of pure DN, isolated NDRD or NDRD superimposed on DN.

RESULTS

Out of the 273 T2D patients, 68 (24.9 %) had DN, 175 (64.1 %) had NDRD, and 30 (11.0 %) had NDRD superimposed on DN. Idiopathic membranous nephropathy (IMN, 29.7 %) was the most common NDRD followed by IgA nephropathy (IgAN, 22.9 %), and hypertensive renal arteriolar sclerosis was the most common lesion in patients diagnosed as NDRD superimposed on DN. Patients with NDRD had a shorter duration of diabetes and lower frequencies of diabetic retinopathy (DR, 6.9 %) and renal failure (28.0 %), which is consistent with higher estimated glomerular filtration rates (eGFR) and lower systolic blood pressure (SBP). No significant between-group differences were observed with respect to proteinuria and hematuria.

CONCLUSION

Renal biopsy is strongly recommended for T2D patients to distinguish DN, NDRD and NDRD superimposed on DN, especially in patients with no signs of DR. This approach may help in early diagnosis and treatment of NDRD and improve renal outcomes in northeastern Chinese T2D patients.