Chronic kidney disease Urological and Genital Diseases Chronic kidney disease
Conditions
Interventions
Oral sodium bicarbonate 500 mg three times a day, rising to 1 g three times a day or matching placebo
Sponsors
Tayside Medical Sciences Centre (UK)
Eligibility
Sex/Gender
All
Inclusion criteria
Inclusion criteria: Current inclusion criteria as of 10/07/2015: 1. Participant is willing and able to give informed consent for participation in the study 2. Male or female aged 60 years or above 3. Estimated Glomerular Filtration Rate (eGFR) <30 ml/min (i.e. CKD stages 4 and 5) found at screening visit 4. Serum Bicarbonate <22 mmol/L 5. Able (in the Investigators opinion) and willing to comply with all study requirements Previous inclusion criteria: 1. Participant is willing and able to give informed consent for participation in the study 2. Male or female aged 65 years or above 3. Estimated Glomerular Filtration Rate (eGFR) <30 ml/min (i.e. CKD stages 4 and 5) found at screening visit 4. Serum Bicarbonate <22 mmol/L 5. Able (in the Investigators opinion) and willing to comply with all study requirements
Exclusion criteria
Exclusion criteria: Current exclusion criteria as of 10/07/2015: 1. Severe cognitive impairment precluding written informed consent 2. Already taking bicarbonate therapy; those taking bicarbonate therapy may be included after a 3 month washout period. 3. Documented renal tubular acidosis (such patients are likely to require bicarbonate, often in very large doses) 4. On renal replacement therapy (haemodialysis or peritoneal dialysis) 5. Anticipated to start renal replacement therapy within 3 months 6. Severe cognitive impairment precluding written informed consent 7. Participant who is terminally ill, as defined as less than 3 months expected survival 8. Decompensated chronic heart failure (to ensure that fluid overload is not exacerbated by the additional sodium load from the intervention) 9. Bisphosphonate therapy (to avoid obscuring bone turnover effects; patients with CKD stages 4/5 should not usually be taking bisphosphonates as this is a listed contraindication) 10. Uncontrolled hypertension (BP>150/90 despite use of four agents) unless evidence of well controlled blood pressure e.g. 24 hour BP readings or home readings Previous exclusion criteria: 1. Severe cognitive impairment precluding written informed consent 2. Already taking bicarbonate therapy 3. Documented renal tubular acidosis (such patients are likely to require bicarbonate, often in very large doses) 4. On renal replacement therapy (haemodialysis or peritoneal dialysis) 5. Anticipated to start renal replacement therapy within 3 months 6. Severe cognitive impairment precluding written informed consent 7. Participant who is terminally ill, as defined as less than 3 months expected survival 8. Decompensated chronic heart failure (to ensure that fluid overload is not exacerbated by the additional sodium load from the intervention) 9. Bisphosphonate therapy (to avoid obscuring bone turnover effects; patients with CKD stages 4/5 should not usually be taking bisphosphonates as this is a listed contraindication) 10. Calcium carbonate use (to avoid interaction with bicarbonate) 11. Sevelamer hydrochloride use (to avoid increasing acid load) 12. Uncontrolled hypertension (BP>150/90 despite use of four agents)
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| Change in Short Physical Performance Battery (SPPB) between baseline and 12 months | — |
Secondary
| Measure | Time frame |
|---|---|
| Current secondary outcome measures as of 10/07/2015: 1. EQ-5D 2. SPPB (baseline, 3, 6, 24 months) 3. Serum sodium, potassium, magnesium, urea, bicarbonate, calcium, phosphate, alkaline phosphatase, creatinine (eGFR calculated by MDRD4 equation), albumin, haemoglobin, thyroid function, HbA1c, lipids 4. Cystatin C 5. Urinary protein/creatinine ratio and urinary albumin/creatinine ratio 6. Height (at screening visit only), weight and anthropometric data (mid arm circumference; triceps skinfold thickness; mid thigh circumference) 7. Handgrip strength measured using dynamometry 8. Six minute walk test 9. KDQoL, a disease-specific quality of life measure 10. Office blood pressure. 3 readings will be taken; the mean of the 2nd and 3rd reading will be used as the outcome 11. Commencement on dialysis 12. All-cause mortality (via General Register Office death records) 13. Death from end-stage renal failure 14. Cardiovascular mortality 15. All hospitalisations (via hospital and GP morbidity records; including heart failure, other cardiovascular and renal-related hospitalisations) 16. Outpatients and general practitioner (GP) visits 17. Changes in medication use, with particular focus on vascular medications and phosphate binders 18. Fractures will be recorded by direct patient report, verified with GP and hospital records 19. Falls will be recorded prospectively using the validated falls diary method 20. Information on side effects (e.g. nausea, indigestion, ankle oedema) will be sought by patient self-report. Adherence to study medication will be assessed by tablet counting. 21. Bone and Vascular Secondary outcomes (measured at baseline, 12 and 2 | — |
Countries
United Kingdom
Outcome results
None listed