Association between renal vasculature changes and generalized atherosclerosis: an autopsy survey

Ankle-Brachial Index Predicts Long-Term Renal Outcomes in Acute Stroke Patients

Renal dysfunction is common after stroke. We aimed to investigate the clinical predictability of the ankle−brachial index (ABI) and brachial-ankle pulse wave velocity (baPWV) on poststroke renal deterioration. A total of 956 consecutive participants with acute ischemic stroke between 1 July 2016, and 31 December 2017 were enrolled and a final of 637 patients were recruited for final analysis. By using the group-based trajectory model (GBTM), the patients’ renal function trajectories were grouped into the low, intermediate, and high categories (LC, IC, and HC). Significant deterioration in the slope was noted in the IC (p < 0.001) and LC (p = 0.002) groups but was nonsignificant in the HC (p = 0.998) group. Abnormal ABI (ABI ≤ 0.9) was independently related to LC (adjusted odds ratio: 2.40; 95% CI, 1.16−4.95; p = 0.019) and was also independently associated with increased risks of a ≥30% decline in eGFR (adjusted hazard ratio [aHR], 2.28; 95% CI, 1.29−4.05; p = 0.005), a doubling of serum creatinine (aHR, 3.60; 95% CI, 1.93−8.34; p < 0.001) and ESRD (HR, 3.28; 95% CI, 1.23−8.74; p = 0.018). However, baPWV did not have a significant relationship with any of the renal outcomes. Patients with a lower ABI during acute stroke should receive regular renal function tests and should be closely monitored to improve poststroke renal care.

Autopsy study examining non-chronic kidney disease versus chronic kidney disease caused by hypertensive-nephrosclerosis in elderly subjects

BACKGROUND

The aim of this autopsy study was to clarify the differences of renal histopathology between non-chronic kidney disease (CKD) and CKD caused by hypertensive-nephrosclerosis in the elderly and during the aging process.

METHODS

We examined autopsy specimens from 105 elderly patients (53 male subjects; mean age, 86.2 years) including 44 patients with CKD as a result of nephrosclerosis. The analysis was divided into two groups depending on whether they had CKD.

RESULTS

The incidences of arterial intimal thickening (AIT), obsolescent-type global glomerulosclerosis (OB), and interstitial fibrosis and tubular atrophy (IF/TA) were higher in the CKD group than in the non-CKD group (all p < 0.01). These factors were all correlated with each other (AIT vs. OB, r = 0.43; AIT vs. IF/TA, r = 0.25; OB vs. IF/TA, r = 0.53). IF/TA had the strongest association with hypertension and decreased eGFR. In the non-CKD group, the frequency of OB was more than 20% in subjects aged 90 years or older. However, the individuals in the non-CKD group tended to have compensatory glomerular hypertrophy with increasing age and a retained eGFR, while the CKD group was unable to obtain compensatory hypertrophy and had a lower eGFR. We also found that AIT, OB and IF/TA occurred independently of systemic atherosclerosis.

CONCLUSIONS

Non-CKD in the elderly refers to the so-called aging kidney. The progression from aging kidney to CKD caused by nephrosclerosis was influenced by increases in AIT, OB and IF/TA. IF/TA was thought to be the most important downstream factor in the progression of aging kidney to CKD.

Vascular Calcification as a Novel Risk Factor for Kidney Function Deterioration in the Nonelderly

Background

The relationship between vascular calcification and chronic kidney disease is well known. However, whether vascular calcification affects renal function deterioration remains unclear. We investigated whether kidney function deteriorated more rapidly in individuals with higher vascular calcification indicated by the coronary artery calcium score (CACS).

Methods and Results

Individuals with a normal estimated glomerular filtration rate (>60 mL/min per 1.73 m²) who underwent cardiac computed tomography in our institution (a tertiary teaching hospital in Cheonan, Korea) from January 2010 to July 2012 were retrospectively reviewed. All participants were aged 20 to 65 years. Among 739 patients, 447, 175, and 117 had CACSs of 0, 1 to 99, and ≥100 units, respectively. The participants were followed for 7.8 (interquartile range, 5.5–8.8) years. The adjusted annual estimated glomerular filtration rates declined more rapidly in patients in the CACS ≥100 group compared with those in the CACS 0 group (adjusted‐β, −0.40; 95% CI, −0.80 to −0.03) when estimated using a linear mixed model. The adjusted hazard ratio in the CACS ≥100 group for Kidney Disease: Improving Global Outcomes criteria (a drop in estimated glomerular filtration rate category accompanied by a 25% or greater drop in estimated glomerular filtration rate) was 2.52 (1.13–5.61). After propensity score matching, more prevalent renal outcomes (13.2%) were observed in patients with a CACS of ≥100 compared with those with a CACS of 0 (1.9%), with statistical significance (P=0.004).

Conclusions

Our results showed that renal function declined more rapidly in patients with higher CACSs, suggesting that vascular calcification might be associated with chronic kidney disease progression.

Ankle-Brachial Index is a Predictor of Future Incident Chronic Kidney Disease in a General Japanese Population

AIMS

The ankle-brachial index (ABI) can be a prognostic marker for chronic kidney disease (CKD) in Western populations. Since there is little relevant evidence for Asian populations, we investigated the relationship between ABI and the risk of incident CKD in a general Japanese population.

METHODS

The cohort included 5,072 participants aged 30-79 without a history of renal disease or cerebro-cardiovascular disease. Incident CKD, defined as an estimated glomerular filtration rate ＜60 (mL/min/1.73 m2) and/or proteinuria (≥ 1＋ on urine dipstick), was compared among participants grouped according to baseline ABI: 0.90-0.99, 1.00-1.09, 1.10-1.19, 1.20-1.29, and 1.30-1.39. Hazard ratios for incident CKD were estimated using a Cox proportional hazards model, with the ABI 1.10-1.19 group serving as the reference.

RESULTS

The CKD incidence rate (/100 person-years) was 1.80 during the mean follow-up period of 5.1 years. The CKD incidence rate was 3.04 in the ABI category 0.90-0.99, 1.58 in ABI 1.00-1.09, 1.72 in ABI 1.10-1.19, 2.01 in ABI 1.20-1.29, and 3.33 in ABI 1.30-1.39. The hazard ratios for developing CKD were 2.14 (95% confidence interval 1.16-3.92) in ABI 0.90-0.99, 1.08 (0.83-1.41) in ABI 1.00-1.09, 1.03 (0.83-1.29) in ABI 1.20-1.29, and 1.37 (0.77-2.47) in ABI 1.30-1.39, after adjusting for age, sex, systolic blood pressure, diabetes, and other confounding factors.

CONCLUSIONS

In a general Japanese population, an ABI of 0.90-0.99 was associated with an increased risk of incident CKD, independent of traditional cardiovascular risk factors.