Investigations of the Optimum Serum Bicarbonate Level in Renal Disease.

Inclusion Criteria:

• Veteran
• Age older than 18 years
• Diabetes mellitus
• Serum bicarbonate 22 - 28 mmol/L on the most recent measurement within the past six months
• Stage 2, 3, or 4 CKD (defined as eGFR 15 - 89 ml/min/1.73m2 using the CKD-EPI equation)
• Urinary albumin:creatinine ratio > 30 mg/gm on the most recent sample within the past 12 months.

Exclusion Criteria:

• Lean body weight > 100 kg
• Use of oral medications typically prescribed to raise low serum bicarbonate levels (i.e. sodium bicarbonate, sodium citrate, potassium citrate).
• Serum potassium < 3.5 meq/L at enrollment visit
• Use of 5 or more antihypertensive agents, regardless of the indications of each agent
• Systolic blood pressure > 140 mmHg or diastolic blood pressure > 90 mmHg at the enrollment or baseline visit
• Diagnosis of congestive heart failure with current, active Class III or IV New York Heart Association symptoms.
• Significant fluid overload such that it is unsafe in the opinion of the PI for the patient to participate in the trial
• chronic gastrointestinal disorder or any other factors judged to be likely to limit adherence to interventions (i.e. alcoholism, a history of missing clinic visits)
• Chronic immunosuppressive therapy for transplanted organs or other indications

• Individuals who are currently a member of a vulnerable population (I.e. incarcerated, pregnant).

  11.Currently participating in another interventional research study