-
1.
Effects of veverimer on serum bicarbonate and physical function in women with chronic kidney disease and metabolic acidosis: a subgroup analysis from a randomised, controlled trial.
Mathur, VS, Wesson, DE, Tangri, N, Li, E, Bushinsky, DA
BMC nephrology. 2022;(1):82
Abstract
BACKGROUND Globally, the prevalence of chronic kidney disease (CKD) is higher in women than in men; however, women have been historically under-represented in nephrology clinical trials. Metabolic acidosis increases risk of progressive loss of kidney function, causes bone demineralization and muscle protein catabolism, and may be more consequential in women given their lower bone and muscle mass. Veverimer, an investigational, non-absorbed polymer that binds and removes gastrointestinal hydrochloric acid, is being developed as treatment for metabolic acidosis. METHODS This was a Phase 3, multicenter, randomised, blinded, placebo-controlled trial in 196 patients with CKD (eGFR: 20-40 mL/min/1.73 m2) and metabolic acidosis who were treated for up to 1 year with veverimer or placebo. We present the findings from a pre-specified subgroup analysis evaluating the effects of veverimer on metabolic acidosis and physical function among women (N = 77) enrolled in this trial. RESULTS At week 52, women treated with veverimer had a greater increase in mean (± standard error) serum bicarbonate than the placebo group (5.4 [0.5] vs. 2.2 [0.6] mmol/L; P < 0.0001). Physical Function reported by patients on the Kidney Disease and Quality of Life - Physical Function Domain, a measure that includes items related to walking, stair climbing, carrying groceries and other activities improved significantly in women randomized to veverimer vs placebo (+ 13.2 vs. -5.2, respectively, P < 0.0031). Objectively measured performance time on the repeated chair stand test also improved significantly in the veverimer group vs. placebo (P = 0.0002). CONCLUSIONS Veverimer was effective in treating metabolic acidosis in women with CKD, and significantly improved how they felt and functioned. TRIAL REGISTRATION ClinicalTrials.gov Identifier: NCT03390842 . Registered on January 4, 2018.
-
2.
Effect of Bicarbonate on Net Acid Excretion, Blood Pressure, and Metabolism in Patients With and Without CKD: The Acid Base Compensation in CKD Study.
Tyson, CC, Luciano, A, Modliszewski, JL, Corcoran, DL, Bain, JR, Muehlbauer, M, Ilkayeva, O, Pourafshar, S, Allen, J, Bowman, C, et al
American journal of kidney diseases : the official journal of the National Kidney Foundation. 2021;(1):38-47
-
-
Free full text
-
Abstract
RATIONALE & OBJECTIVE Patients with CKD are at elevated risk of metabolic acidosis due to impaired net acid excretion (NAE). Identifying early markers of acidosis may guide prevention in chronic kidney disease (CKD). This study compared NAE in participants with and without CKD, as well as the NAE, blood pressure (BP), and metabolomic response to bicarbonate supplementation. STUDY DESIGN Randomized order, cross-over study with controlled feeding. SETTING & PARTICIPANTS Participants consisted of 8 patients with CKD (estimated glomerular filtration rate 30-59mL/min/1.73m2 or 60-70mL/min/1.73m2 with albuminuria) and 6 patients without CKD. All participants had baseline serum bicarbonate concentrations between 20 and 28 mEq/L; they did not have diabetes mellitus and did not use alkali supplements at baseline. INTERVENTION Participants were fed a fixed-acid-load diet with bicarbonate supplementation (7 days) and with sodium chloride control (7 days) in a randomized order, cross-over fashion. OUTCOMES Urine NAE, 24-hour ambulatory BP, and 24-hour urine and plasma metabolomic profiles were measured after each period. RESULTS During the control period, mean NAE was 28.3±10.2 mEq/d overall without differences across groups (P=0.5). Urine pH, ammonium, and citrate were significantly lower in CKD than in non-CKD (P<0.05 for each). Bicarbonate supplementation reduced NAE and urine ammonium in the CKD group, increased urine pH in both groups (but more in patients with CKD than in those without), and increased; urine citrate in the CKD group (P< 0.2 for interaction for each). Metabolomic analysis revealed several urine organic anions were increased with bicarbonate in CKD, including 3-indoleacetate, citrate/isocitrate, and glutarate. BP was not significantly changed. LIMITATIONS Small sample size and short feeding duration. CONCLUSIONS Compared to patients without CKD, those with CKD had lower acid excretion in the form of ammonium but also lower base excretion such as citrate and other organic anions, a potential compensation to preserve acid-base homeostasis. In CKD, acid excretion decreased further, but base excretion (eg, citrate) increased in response to alkali. Urine citrate should be evaluated as an early and responsive marker of impaired acid-base homeostasis. FUNDING National Institute of Diabetes and Digestive and Kidney Diseases and the Duke O'Brien Center for Kidney Research. TRIAL REGISTRATION Registered at ClinicalTrials.gov with study number NCT02427594.
-
3.
Serum bicarbonate and cardiovascular events in hypertensive adults: results from the Systolic Blood Pressure Intervention Trial.
Dobre, M, Pajewski, NM, Beddhu, S, Chonchol, M, Hostetter, TH, Li, P, Rahman, M, Servilla, K, Weiner, DE, Wright, JT, et al
Nephrology, dialysis, transplantation : official publication of the European Dialysis and Transplant Association - European Renal Association. 2020;(8):1377-1384
-
-
Free full text
-
Abstract
BACKGROUND Low serum bicarbonate level is associated with increased mortality, but its role as a predictor of cardiovascular disease (CVD) is unclear. This study evaluates the association between serum bicarbonate concentration and CVD and whether the effect of intensive blood pressure (BP) lowering on CVD outcomes is modified by serum bicarbonate level. METHODS The Systolic Blood Pressure Intervention Trial (SPRINT) randomized participants to a systolic BP target <120 mmHg (intensive treatment) or <140 mmHg (standard treatment). The primary CVD outcome was a composite of nonfatal myocardial infarction (MI), acute coronary syndrome not resulting in MI, stroke, acute decompensated heart failure and CVD death. Cox proportional hazards models adjusted for demographic, clinical and laboratory characteristics were used to evaluate the association of interest in 9334 SPRINT participants (ClinicalTrials.gov: NCT01206062). RESULTS Over a median follow-up of 3.33 years (interquartile range 2.87-3.87 years), 618 (6.6%) participants experienced a primary CVD outcome. Participants with serum bicarbonate <22 mEq/L had a significantly higher risk of the primary CVD outcome (hazard ratio 1.54; 95% confidence interval 1.11-2.14, P = 0.01), compared with participants with bicarbonate 22-26 mEq/L. The magnitude of the CVD risk reduction with intensive BP lowering was similar across bicarbonate strata (P-value for interaction = 0.97). CONCLUSIONS In hypertensive individuals, serum bicarbonate level <22 mEq/L was associated with an increased CVD risk. The effect of intensive BP lowering on CVD outcomes was not modified by the serum bicarbonate level.
-
4.
Clinical and cost-effectiveness of oral sodium bicarbonate therapy for older patients with chronic kidney disease and low-grade acidosis (BiCARB): a pragmatic randomised, double-blind, placebo-controlled trial.
,
BMC medicine. 2020;(1):91
Abstract
BACKGROUND Chronic kidney disease with metabolic acidosis is common in older people, but the effectiveness of oral sodium bicarbonate therapy in this group is unclear. We tested whether oral sodium bicarbonate provides net health benefit for older people with advanced chronic kidney disease and serum bicarbonate concentrations < 22 mmol/L. METHODS Pragmatic multicentre, parallel group, double-blind, placebo-controlled randomised trial. We recruited adults aged ≥ 60 years with estimated glomerular filtration rate of < 30 mL/min/1.73 m2, not receiving dialysis, with serum bicarbonate concentration < 22 mmol/L, from 27 nephrology and geriatric medicine departments in the UK. Participants received oral sodium bicarbonate (up to 3 g/day) or matching placebo given for up to 2 years, randomised in a 1:1 ratio. The primary outcome was between-group difference in the Short Physical Performance Battery (SPPB) at 12 months, adjusted for baseline values, analysed by intention to treat. Secondary outcomes included generic and disease-specific quality of life (EQ-5D and KDQoL tools), anthropometry, renal function, walk distance, blood pressure, bone and vascular health markers, and incremental cost per quality-adjusted life year gained. RESULTS We randomised 300 participants between May 2013 and February 2017, mean age 74 years, 86 (29%) female. At 12 months, 116/152 (76%) participants allocated to bicarbonate and 104/148 (70%) allocated to placebo were assessed; primary outcome data were available for 187 participants. We found no significant treatment effect for the SPPB bicarbonate arm 8.3 (SD 2.5) points, placebo arm 8.8 (SD 2.2) and adjusted treatment effect - 0.4 (95% CI - 0.9 to 0.1, p = 0.15). We found no significant treatment effect for glomerular filtration rate (0.6 mL/min/1.73 m2, 95% CI - 0.8 to 2.0, p = 0.39). The bicarbonate arm showed higher costs and lower quality of life as measured by the EQ-5D-3L tool over 1 year (£564 [95% CI £88 to £1154]); placebo dominated bicarbonate under all sensitivity analyses. Adverse events were more frequent in those randomised to bicarbonate (457 versus 400). CONCLUSIONS Oral sodium bicarbonate did not improve physical function or renal function, increased adverse events and is unlikely to be cost-effective for use by the UK NHS for this patient group. TRIAL REGISTRATION European Clinical Trials Database (2011-005271-16) and ISRCTN09486651; registered 17 February 2012.
-
5.
Association between change in serum bicarbonate and change in thyroid hormone levels in patients receiving conventional or more frequent maintenance haemodialysis.
Molfino, A, Beck, GJ, Li, M, Lo, JC, Kaysen, GA, ,
Nephrology (Carlton, Vic.). 2019;(1):81-87
-
-
Free full text
-
Abstract
AIM: Correction of metabolic acidosis in patients with chronic kidney disease has been associated with improvement in thyroid function. We examined whether changes in bicarbonate were associated with changes in thyroid function in patients with end-stage renal disease receiving conventional or more frequent haemodialysis. METHODS In the Frequent Hemodialysis Network Trials, the relationship between changes in serum bicarbonate, free triiodothyronine (FT3) and free thyroxine (FT4) was examined among 147 and 48 patients with endogenous thyroid function who received conventional (3×/week) or more frequent (6×/week) haemodialysis (Daily Trial) or who received conventional or more frequent nocturnal haemodialysis (Nocturnal Trial). Equilibrated normalized protein catabolic rate (enPCR) was examined to account for nutritional factors affecting both acid load and thyroid function. RESULTS Increasing dialysis frequency was associated with increased bicarbonate level. Baseline bicarbonate level was not associated with baseline FT3 and FT4. Change in bicarbonate level was not associated with changes in FT3 and FT4 in the Daily Trial nor for FT4 in the Nocturnal Trial (r ≤ 0.14, P > 0.21). While, a significant correlation between change in serum bicarbonate and change in FT3 (r = 0.44, P = 0.02) was observed in the Nocturnal Trial; findings were no longer significant after adjusting for change in enPCR (r = 0.37, P = 0.08). For participants with baseline bicarbonate <23 mmol/L, no association between change in bicarbonate and change in thyroid indices were seen in the Daily Trial; for the Nocturnal Trial, findings were also not significant for change in FT3 and the association between change in bicarbonate and change in FT4 (r = 0.54, P = 0.03) was no longer significant after adjusting for enPCR (r = 0.45, P = 0.11). CONCLUSION Changes in bicarbonate were not associated with changes in thyroid hormone levels after adjusting for enPCR, as a marker of nutritional status. Future studies should examine whether improvement in acid base status improves thyroid function in haemodialysis patients with evidence of thyroid hypofunction.
-
6.
The effects of a novel bicarbonate loading protocol on serum bicarbonate concentration: a randomized controlled trial.
Marcus, A, Rossi, A, Cornwell, A, Hawkins, SA, Khodiguian, N
Journal of the International Society of Sports Nutrition. 2019;(1):41
Abstract
BACKGROUND Previous studies have shown that sodium bicarbonate ingestion may enhance intense exercise performance, but may also cause severe gastrointestinal distress. The purpose of this study was to determine whether a modified sodium bicarbonate (SB) ingestion protocol would elevate serum bicarbonate concentration more than previous methods without causing gastrointestinal distress. METHODS In randomized order, seven (5 men, 2 women) elite middle-distance runners ingested either placebo, Modified SB (600 mg·kg- 1 over 19.5 h), or Acute SB (300 mg·kg- 1) in opaque gelatin capsules. Baseline and post-ingestion blood samples were analyzed for bicarbonate, pH, sodium, hematocrit, and lactate. Repeated measures ANOVA (2 time points × 3 conditions) were analyzed to determine differences in serum bicarbonate, lactate, sodium, blood pH, and hematocrit. Gastrointestinal distress was assessed via self-report on a Likert scale of 1-10. Simple (condition) and repeated (time) within-participant contrasts were used to determine the location of any statistically significant main and interaction effects (p ≤ 0.05). RESULTS Both Modified SB (7.6 mmol·L- 1, p < 0.01) and Acute SB (5.8 mmol·L- 1, p < 0.01) increased serum bicarbonate concentration compared to the placebo (p ≤ 0.05). Post-ingestion serum bicarbonate concentration was significantly higher for the Modified SB (34.7 ± 2.2 mmol·L- 1, 28.0% increase) trials than the Acute SB (33.5 ± 2.0 mmol·L- 1, 20.9% increase) trials (p = 0.05). There was no reported severe GI distress in the Modified SB trials, but two cases in the Acute SB trials. CONCLUSIONS Modified SB elevated serum bicarbonate concentration more than Acute SB, without any severe gastrointestinal side effects. Consequently, it is recommended that future experimentation involving SB by researchers and athletes use the novel ingestion protocol described in this study due to its potential for improved effectiveness and reduced gastrointestinal impact. TRIAL REGISTRATION ClinicalTrials.gov , NCT03813329 . Registered 23 January 2019 - Retrospectively registered.
-
7.
HYDration and Bicarbonate to Prevent Acute Renal Injury After Endovascular Aneurysm Repair With Suprarenal Fixation: Pilot/Feasibility Randomised Controlled Study (HYDRA Pilot Trial).
Saratzis, A, Chiocchia, V, Jiffry, A, Hassanali, N, Singh, S, Imray, CH, Bown, MJ, Mahmood, A
European journal of vascular and endovascular surgery : the official journal of the European Society for Vascular Surgery. 2018;(5):648-656
Abstract
OBJECTIVE/BACKGROUND Up to 25% of patients undergoing elective endovascular aneurysm repair (EVAR) develop acute kidney injury (AKI), which is associated with short and long-term morbidity and mortality. There is no high quality randomised evidence regarding prevention of EVAR related AKI. METHODS A novel AKI prevention strategy for EVAR was devised, based on best evidence and an expert consensus group. This included a bolus of high dose sodium bicarbonate (NaHCO3) immediately before EVAR (1 mL/kg of 8.4% NaHCO3) and standardised crystalloid based hydration pre- and post-EVAR. A pilot/feasibility randomised controlled trial (RCT) was performed in two centres to assess the safety of the intervention, potential impact on AKI prevention, and feasibility of a national RCT; the primary end point was the proportion of eligible patients recruited into the study. AKI was defined using "Kidney Disease Improving Global Outcomes" and "Acute Kidney Injury Network" criteria based on National Institute for Health and Clinical Excellence AKI recommendations, using serum creatinine and hourly urine output. RESULTS Fifty-eight patients (84% of those screened; median age 75 years [range 57-89 years], 10% female) were randomised to receive the standardised intravenous hydration with (intervention) or without (control) NaHCO3. Groups were comparable in terms of AKI risk factors; 56 of 58 participants had a device with suprarenal fixation. Overall, 33% of patients in the control arm developed AKI versus 7% in the intervention arm (as treated analysis). None of the patients receiving NaHCO3 developed a serious intervention related adverse event; five patients did not attend their 30 day follow-up. CONCLUSION Bolus high dose NaHCO3 and hydration is a promising EVAR related AKI prevention method. This trial has confirmed the feasibility of delivering a definitive large RCT to confirm the efficacy of this novel intervention, in preventing EVAR related AKI.
-
8.
Randomized, Controlled Trial of TRC101 to Increase Serum Bicarbonate in Patients with CKD.
Bushinsky, DA, Hostetter, T, Klaerner, G, Stasiv, Y, Lockey, C, McNulty, S, Lee, A, Parsell, D, Mathur, V, Li, E, et al
Clinical journal of the American Society of Nephrology : CJASN. 2018;(1):26-35
-
-
Free full text
-
Abstract
BACKGROUND AND OBJECTIVES Metabolic acidosis is common in patients with CKD and has significant adverse effects on kidney, muscle, and bone. We tested the efficacy and safety of TRC101, a novel, sodium-free, nonabsorbed hydrochloric acid binder, to increase serum bicarbonate in patients with CKD and metabolic acidosis. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS One hundred thirty-five patients were enrolled in this randomized, double-blind, placebo-controlled, multicenter, in-unit study (designated the TRCA-101 Study). Patients had a mean baseline eGFR of 35 ml/min per 1.73 m2, a mean baseline serum bicarbonate of 17.7 mEq/L, and comorbidities, including hypertension (93%), diabetes (70%), and heart failure (21%). Patients ate a controlled diet and were treated for 14 days with placebo or one of four TRC101 dosing regimens (1.5, 3, or 4.5 g twice daily or 6 g once daily). After treatment, patients were discharged and followed for 7-14 days. RESULTS All TRC101 treatment groups had a mean within-group increase in serum bicarbonate of ≥1.3 mEq/L (P<0.001) within 72 hours of the first dose and a mean increase in serum bicarbonate of 3.2-3.9 mEq/L (P<0.001) at the end of treatment compared with placebo, in which serum bicarbonate did not change. In the combined TRC101 treatment group, serum bicarbonate was normalized (22-29 mEq/L) at the end of treatment in 35% of patients and increased by ≥4 mEq/L in 39% of patients. After discontinuation of TRC101, serum bicarbonate decreased nearly to baseline levels within 2 weeks. All adverse events were mild or moderate, with gastrointestinal events most common. All patients completed the study. CONCLUSIONS TRC101 safely and significantly increased the level of serum bicarbonate in patients with metabolic acidosis and CKD.
-
9.
A Phase 4, multicentre, randomized, single-blind clinical trial to evaluate the immunogenicity of the live, attenuated, oral rotavirus vaccine (116E), ROTAVAC®, administered simultaneously with or without the buffering agent in healthy infants in India.
Ella, R, Bobba, R, Muralidhar, S, Babji, S, Vadrevu, KM, Bhan, MK
Human vaccines & immunotherapeutics. 2018;(7):1791-1799
-
-
Free full text
-
Abstract
BACKGROUND The World Health Organization recommends that rotavirus vaccines should be included in all national immunization programs. Some currently licensed oral rotavirus vaccines contain a buffering agent (either as part of a ready-to-use liquid formulation or added during reconstitution) to reduce possible degradation of the vaccine virus in the infant gut, which poses several programmatic challenges (the large dose volume or the reconstitution requirement) during vaccine administration. Because ROTAVAC®, a WHO prequalified vaccine, was derived from the 116E neonatal strain, we evaluated the immunogenicity and safety of ROTAVAC® without buffer and ROTAVAC® with buffer in a phase 4, multicentre, single-blind, randomized clinical trial in healthy infants in India. METHODS 900 infants, approximately 6, 10 and 14 weeks of age, were assigned to 3 groups to receive ROTAVAC® (0.5 mL dose) orally: (i) 2.5 mL of citrate-bicarbonate buffer 5 minutes prior to administration of ROTAVAC® (Group I), (ii) ROTAVAC®, alone, without any buffer (Group II), or (iii) ROTAVAC®, mixed with buffer immediately before administration (Group III). Non-inferiority was compared among the groups for differences in serological responses (detected by serum anti-rotavirus IgA) and safety. RESULTS Geometric mean titers post vaccination at day 84 (28 days after dose 3) were 19.6 (95%CI: 17.0, 22.7), 20.7 (95%CI: 17.9, 24) and 19.2 (95%CI: 16.8, 22.1) for groups I, II and III respectively. Further, seroconversion rates and distribution of adverse events were similar among groups. CONCLUSIONS Administration of ROTAVAC® at a 0.5 mL dose volume without buffering agent was shown to be well tolerated and immunogenic. Given the homologous nature of the strain, it is plausible that ROTAVAC® replicates well and confers immunity even without buffer administration.
-
10.
Increasing alkali supplementation decreases urinary nitrogen excretion when adjusted for same day nitrogen intake.
Ceglia, L, Dawson-Hughes, B
Osteoporosis international : a journal established as result of cooperation between the European Foundation for Osteoporosis and the National Osteoporosis Foundation of the USA. 2017;(12):3355-3359
-
-
Free full text
-
Abstract
UNLABELLED We examined whether escalating doses of potassium bicarbonate (KHCO3) supplements alter urinary nitrogen excretion expressed as a ratio to same day nitrogen intake (measure of muscle-protein breakdown). The ratio declined significantly from placebo to low to high dose of KHCO3 supplementation in older adults over 3 months, suggesting muscle-sparing. INTRODUCTION Neutralization of dietary acid load with alkali supplementation (i.e., KHCO3) has been hypothesized to have muscle protein-sparing effects. In controlled feeding studies with fixed nitrogen (N) intake/day, 24-h urinary N excretion is a good marker of muscle breakdown. However, in studies with self-selected diets, changes in 24-h urinary N excretion can be influenced by shifts in N intake. METHODS We evaluated changes in 24-h total urinary N excretion as a ratio of N excretion to concurrent N intake in 233 older men and women who participated in an 84-day KHCO3 supplementation randomized placebo-controlled trial. RESULTS After adjustment for relevant cofactors, escalating doses of KHCO3 (1 mmol/kg/day [low] or 1.5 mmol/kg/day [high]) resulted in a progressive decline in urinary N excretion/N intake compared to placebo (overall P for trend = 0.042). The 84-day change in urinary N excretion/N intake in the high-dose KHCO3 group was statistically significantly lower compared to placebo (P = 0.012) but not compared to the low-dose KHCO3 group (P = 0.276). The 84-day change in urinary N excretion/N intake in the low-dose KHCO3 group did not differ significantly from placebo (P = 0.145). CONCLUSIONS Urinary N excretion expressed as ratio to same day N intake declined steadily with increasing doses of KHCO3 supplementation from low 1 mmol/kg/day to high 1.5 mmol/kg/day, suggesting a nitrogen-sparing effect. Compared to urinary N excretion alone, this ratio could be a more reasonable measure of muscle protein metabolism in large-scale long-term human studies. TRIAL REGISTRATION Clinicaltrials.gov NCT1475214.