Skin Perfusion Pressure Outperforms Ankle-Brachial Index in Predicting Mortality and Cardiovascular Outcomes in Hemodialysis Patients.

AIMS: Skin perfusion pressure (SPP) and ankle-brachial index (ABI) are useful in screening for peripheral arterial disease in patients undergoing hemodialysis (HD). We compared the prognostic abilities of the SPP and ABI in predicting the composite outcomes of mortality and atherosclerotic vascular events. METHODS: This single-center prospective cohort study enrolled 258 patients undergoing HD. The patients with SPP and ABI measurements were divided into tertiles. Log-rank tests, Cox regression analyses, and discrimination parameters were used for comparisons. RESULTS: Over a median follow-up period of 3.7 (1.4-5.0) years, 119 composite events were recorded. The incidence rates of composite events were 27.5, 13.3, and 9.1 per 100 person years, respectively, across the SPP tertiles (log-rank: p＜0.001), and 23.2, 13.2, and 11.6 per 100 person years across the ABI tertiles (p=0.003). With the 3rd tertiles as references, the 1st tertiles of the SPP and ABI were significantly associated with the composite outcome (adjusted hazard ratio [aHR]: 2.58, 95% confidence interval [CI]: 1.57-4.23 and aHR: 1.70, 95% CI: 1.06-2.73, respectively). Adding the tertiles of the SPP to a predictive model with established risk factors significantly improved the model performance. This improvement was larger than that of the ABI in terms of net reclassification (0.330 vs. 0.275) and integrated discrimination (0.045 vs. 0.012). Furthermore, in patients with a normal ABI, the 1st SPP tertile (＜71 mmHg) was significantly associated with the outcome (aHR, 1.97; 95% CI, 1.13-3.41) when compared to the 3rd tertile. CONCLUSIONS: Even patients with a normal ABI have a poor prognosis if their SPP levels are low. SPP outperformed ABI in predicting mortality and cardiovascular outcomes in HD patients.

Nephrology referral slows the progression of chronic kidney disease, especially among patients with anaemia, diabetes mellitus, or hypoalbuminemia: A single-centre, retrospective cohort study.

BACKGROUND: The Kidney Disease Improving Global Outcomes guidelines recommend nephrology referral for patients with chronic kidney disease (CKD) stages 4 to 5, significant proteinuria and persistent microscopic haematuria. However, the recommendations are opinion-based and which patients with CKD benefit more from nephrology referral has not been elucidated. METHODS: In this retrospective cohort study, patients referred to our nephrology outpatient clinic from April 2017 to March 2019 were included. We excluded patients considered to have an acute decline in kidney function (annual decline in estimated glomerular filtration rate [eGFR] >10 mL/min/1.73 m2). The slopes of eGFR before and after nephrology referral were estimated and compared by linear mixed effects models. Interaction between time and referral status (before or after referral) was assessed and effect modifications by the presence of diabetes, proteinuria (defined by urine dipstick protein 2+ or more), urine occult blood, hypoalbuminemia (defined by albumin levels less than 3.5 g/dL) and anaemia (defined by haemoglobin levels less than 11.0 g/dL) were evaluated. RESULTS: The eGFR slope significantly improved from -2.05 (-2.39 to -1.72) to -0.96 (-1.36 to -0.56) mL/min/1.73 m2/year after nephrology referral (p < .001). The improvement in eGFR slope was more prominent among those with diabetes mellitus, anaemia, and hypoalbuminemia (all p-values for three-way interaction <.001 after adjustment for covariates). Further adjustments for time-dependent haemoglobin levels, the use of erythropoiesis-stimulating agents, iron supplementation, anti-hypertensives and anti-diabetic medications did not change the significance of the interactions. CONCLUSIONS: Nephrology referral slows CKD progression, especially among those with hypoalbuminemia, diabetes or anaemia. Patients with hypoalbuminemia, diabetes or anaemia might benefit more from specialized care and lifestyle modifications by nephrologists. The inclusion of anaemia and hypoalbuminemia in nephrology referral criteria should be considered.

Sodium-glucose cotransporter 2 inhibitors and anemia among diabetes patients in real clinical practice.

AIMS/INTRODUCTION: Sodium-glucose cotransporter 2 inhibitors (SGLT2i) were reported to increase hemoglobin levels in short-term clinical trials. Whether it is also true in real clinical practice is unknown. MATERIALS AND METHODS: This is a retrospective cohort study. Inclusion criterion was diabetes patients who visited our outpatient clinic from January 2019 to August 2020. Exposure of interest was the use of SGLT2i. Outcomes were hemoglobin levels. For the cross-sectional analyses, non-linear regression models were fitted with restricted cubic splines to investigate the association between hemoglobin levels and estimated glomerular filtration rate (eGFR) for users and non-users of SGLT2i. For the case-control study, cases (anemia defined as hemoglobin <120 g/L for men, <110 g/L for women or the use of erythropoiesis stimulating agents) and controls were matched by age, sex and eGFR. RESULTS: Among 2,063 diabetes patients, 723 were taking SGLT2i. In the cross-sectional analyses, hemoglobin levels were higher among SGLT2i users compared with non-users at eGFR >15 mL/min/1.73 m2 . For the case-control study, 197 cases and controls were matched. Conditional logistic regression showed that the use of SGLT2i was associated with significantly lower prevalence of anemia (odd ratio 0.35, 95% confidence interval 0.21-0.58). Adjusted mean differences in hemoglobin levels between users and propensity score-matched non-users of SGLT2i were 7.0 g/L (95% confidence interval 3.0-10.0 g/L) at 6 months. Among SGLT2i users, the odds of an increase in 6-month hemoglobin were similar across eGFR categories, except for eGFR <15 mL/min/1.73 m2 . CONCLUSIONS: The use of SGLT2i was associated with higher hemoglobin levels and lower prevalence of anemia in real clinical practice.