Muscle Loss | Musculoskeletal Effects of Bicarbonate

Muscle Loss research study

What is the primary objective of this study?

With aging, men and women develop a mild and progressive metabolic acidosis. This occurs as a result of declining renal function and ingestion of acid-producing diets. There is extensive evidence that severe metabolic acidosis causes bone and muscle loss, but the impact of the chronic, mild acidosis on bone and muscle in older individuals has not been established. In a recent study, administration of a single dose of bicarbonate daily for 3 months significantly reduced urinary excretion of N-telopeptide (NTX), a marker of bone resorption and urinary nitrogen, a marker of muscle wasting and improved muscle performance in the women but not the men. These and other data support a potential role for bicarbonate as a means of reducing the musculoskeletal declines that lead to extensive morbidity and mortality in the elderly. Before proceeding to a long-term bicarbonate intervention study, however, it is important to identify the dose of bicarbonate most likely to be optimal and to characterize the subjects who benefit most from it. This double blind, placebo controlled, dose-finding study will evaluate the effects of placebo and two doses of bicarbonate on urinary NTX and nitrogen excretion and on lower extremity performance over a 3 month period in 138 men and 138 women, age 60 and older. Changes in urinary excretion of NTX and nitrogen and in selected measures of lower extremity performance will be compared across the three groups. The safety and tolerability of the interventions will also be evaluated. This investigation should provide needed information on the appropriate dosing regimen for men and women and on the study population that should be enrolled in a future bicarbonate intervention trial to assess the long-term effects of this simple, low cost intervention on important clinical outcomes including rates of loss in bone and muscle mass, falls, and fractures.

Who is eligible to participate?

Inclusion Criteria: - men and women - age 60 and older - community dwelling - women 1 yr since last menses Exclusion Criteria: Medications: 1. Oral glucocorticoids for > 10 days in the last 3 months - Cortef (hydrocortisone) - Prednisone 2. Parenteral glucocorticoids • Decadron (dexamethasone) 3. Osteoporosis medications in the last 6 months - Forteo (teriparatide) - Calcimar, Miacalcin (calcitonin) - Evista (raloxifene) 4. Osteoporosis medications in the last 2 years - Fosamax (alendronate) - Didronel (etidronate) - Aredia (pamidronate) - Actonel (risedronate) - Reclast (zoledronate) 5. Tamoxifen in the last 6 months 6. Calcium/Parathyroid - Rocaltrol (calcitriol) - Zemplar (paricalcitol) - Drisdol, Ergocalciferol 7. Diuretics currently - hydrocholorothiazide (HCTZ) - Diuril (chlorothiazide) - Thalitone (chlorthalidone) - Zaroxolyn (metolazone) - Dyazide - Maxide - Moduretic - Lasix (forosamine) - Dyrenium (triamterene) - Midamor 8. Testosterone or estrogen in the last 6 months (vaginal estrogen okay) 9. Angiotensin converting enzyme (ACE) inhibitors currently - Benazepril (Lotensin) - Captopril (Capoten) - Enalapril (Vasotec) - Fosinopril (Monopril) - Lisinopril (Prinivil, Zestril) - Moexipril (Univasc) - Perindopril (Aceon) - Quinapril (Accupril) - Ramipril (Altace) - Trandolapril (Mavik) 10. Angiotensin II receptor blockers currently - Candesartan (Atacand) - Eprosartan (Teveten) - Irbesartan (Avapro) - Losartan (Cozaar) - Olmesartan (Benicar) - Telmisartan (Micardis) - Valsartan (Diovan) Over-the-Counter Drugs currently 1. Antacids - any antacid that contains calcium carbonate, aluminum hydroxide, magnesium hydroxide, or calcium acetate - selected examples include - TUMS - Mylanta - Maalox - Titralac - Rolaids - Sodium bicarbonate (baking soda) - Note: magaldrate or Riopan® is allowed 2. Potassium supplements 3. Salt substitutes Conditions/Diseases 1. renal disease including kidney stones in the past 5 years or glomerular filtration rate (GFR) < 60 ml/min/1.73 m2 2. hyperkalemia (serum potassium >5.3 meq/L; normal range 3.5-5.3 meq/L) 3. elevated serum bicarbonate (serum bicarbonate > 29 mmol/L; normal range 22-29 mmol/L) 4. cirrhosis 5. gastroesophageal reflux disease (GERD) requiring treatment with alkali-containing antacids (TUMS, Mylanta, Maalox, Titralac, Rolaids, or sodium bicarbonate) 6. hyperparathyroidism 7. untreated thyroid disease 8. significant immune disorder such as rheumatoid arthritis 9. current unstable heart disease 10. active malignancy or cancer therapy in the last year 11. fasting spot urine calcium/creatinine > 0.38 mmol/mmol after 1 wk off of calcium supplements 12. congestive heart failure, arrhythmias (surgically treated arrhythmias acceptable), or myocardial infarction in last 12 months 13. serum calcium outside the normal range of 8.3-10.2 mg/dl 14. uncontrolled diabetes mellitus (fasting blood sugar > 130) 15. alcohol use exceeding 2 drinks/day 16. peptic ulcers or esophageal stricture 17. weight <45 or >113.5 kg (<99 or >249.7 lbs) 18. other abnormalities in screening labs, at discretion of the study physician (the PI)

Which medical condition, disease, disorder, syndrome, illness, or injury is researched?

Muscle Loss


Osteoporosis, Age Related

Fall Injury

Study Interventions

Interventions can include giving participants drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available or noninvasive approaches such as surveys, education, and interviews.

Dietary Supplement:potassium bicarbonatepotassium bicarbonate in dose of 1.0 mmol/kg per day, given in three even daily doses after meals with a full glass of water

Dietary Supplement:potassium bicarbonatepotassium bicarbonate in dose of 1.5 mmol/kg per day, given in three even daily doses after meals with a full glass of water

Other:Inactive placebo capsulemicrocrystalline cellulose

Study Arms

Research studies and clinical trials typically have two or more research arms. An arm is a group of people who receive the same treatment in the study.

potassium bicarbonate low dosepotassium bicarbonate in dose of 1.0 mmol/kg per day, given in three even daily doses after meals with a full glass of water

potassium bicarbonate higher dosepotassium bicarbonate in dose of 1.5 mmol/kg per day, given in three even daily doses after meals with a full glass of water

placebomicrocrystalline cellulose

Study Status


Start Date: January 2012

Completed Date: August 2015

Phase: Phase 2

Type: Interventional


Primary Outcome: The Dose of Potassium Bicarbonate Needed for Maximal Suppression of 24-hr Urinary N-telopeptide

Secondary Outcome:

Study sponsors, principal investigator, and references

Principal Investigator: Bess Dawson-Hughes, M.D.

Lead Sponsor: Tufts University

Collaborator: National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS)

More information:

Discuss Potassium