Osteoporosis is a disorder of bone in which the mass of the bone is reduced and the bone's architecture at the microscopic level is disordered. Together those abnormalities predispose affected individuals to experience fractures despite only minimal trauma (i.e., fragility fractures). Age related osteoporosis is a common type of osteoporosis that occurs with aging in both men and women usually beginning after the age of peak bone mass. Research has found that the disorder can be partially reversed by reducing the net amount of acid that is produced when consuming typical Western diets. However, the amelioration that results has not been so dramatic or so consistent that physicians have adopted the procedure as part of the standard treatment for age-related osteoporosis. We propose that reducing the net acid load from the diet is not sufficient to reverse age related osteoporosis because it fails to supply base needed to restore the large amount of base in bone that had been lost by reacting with the net acid load of the diet that had been consumed for years or decades. Reducing the net acid load from the diet might be expected to have little ameliorative effect or merely slow the progression of the disorder. We hypothesize that both to restore osteoporotic bone to, or nearly to, its pre-disease state, as well as to eliminate the risk of fragility fractures, requires consuming diets that produce net amounts of base to restore the base lost from years to decades of consuming diets that produce net amounts of acid. We hypothesize also that the excess base and attendant subclinical metabolic alkalosis will both stimulate the cellular process of bone formation and suppress the cellular process of bone resorption, and thereby implement the restorative process.

Uric acid accumulates in renal failure and is thought to be a uremic toxin-that is, higher levels of uric acid are more damaging to the kidneys. Urate crystals can precipitate in the kidney tubules, cause urate stones, and promote inflammatory changes in the renal interstitium and vascular endothelium. Uric acid is also a small non-protein-bound molecule and therefore easily dialyzable. Here, we present the case of an anuric hemodialysis patient with severe tophaceous gout who regained some renal function and whose gout burden significantly decreased resulting in marked improvement in functional status using a new gout medication, febuxostat, and increased frequency of dialysis.

Objective

Inflammation may be present with chronic kidney disease CKD and diet composition high in protein intake and fats may affect inflammation thereby impacting kidney health. We investigated whether acid load estimated from urine measures is associated with kidney function decline and whether the effect of acid load on an inflammatory marker, serum albumin, is a pathway to this association.

Methods

We studied 188 postmenopausal women in a randomized clinical trial of potassium bicarbonate treatment for up to 36 months. Twenty-four-hour urine and arterialized blood collections were done at baseline and at subsequent follow-up visits at 3 months interval. Acid load was estimated from potential renal acid load calculated using urinary measures of chloride, phosphate, sodium, potassium, calcium, and magnesium (UPRAL). Mixed effects model with random-intercept and slope was used to estimate subjects' annual decline rate in creatinine clearance (CrCl), and the association between (i) UPRAL and serum albumin and (ii) serum albumin and CrCl, adjusting for age, body mass index, systolic BP, and glucose. A Cox proportional regression model was used to study the relative hazard (RH) for rapid progression of kidney function decline (defined as loss of ≥5 mL/min CrCl/yr based on the last CrCl in the rolling window) with UPRAL, adjusting for the potential covariates and baseline CrCl.

Results

A 25 mEq/day increase in UPRAL was inversely associated with serum albumin (Adjusted β[95% CI]: -0.02[-0.09;-0.001). During a mean follow-up of 28 months, 19 women (10%) had a rapid decline in kidney function. For each 25 mEq/day increase in UPRAL, the risk of a rapid decline in CrCl increased by 17% (95% CI: 1.06-1.28). On adjustment for potential confounders, the risk attenuated to 5% (1.02-1.14). Mediation analysis indicated that of the total effect of the association between UPRAL and CrCl, the proportion mediated by serum albumin increased to 0.346 (i.e. 34.6%).

Conclusion

Higher UPRAL was associated with lower serum albumin as well as greater kidney function decline in postmenopausal women. Our findings suggest inflammatory response may exert a modulatory effect on the association of UPRAL and kidney function and might be a potential pathway explaining the effects of systemic acid load on progression of kidney failure.

Modern Western diets, with higher contents of animal compared to fruits and vegetable products, have a greater content of acid precursors vs. base precursors, which results in a net acid load to the body. To prevent inexorable accumulation of acid in the body and progressively increasing degrees of metabolic acidosis, the body has multiple systems to buffer and titrate acid, including bone which contains large quantities of alkaline salts of calcium. Both in vitro and in vivo studies in animals and humans suggest that bone base helps neutralize part of the dietary net acid load. This raises the question of whether decades of eating a high acid diet might contribute to the loss of bone mass in osteoporosis. If this idea is true, then additional alkali ingestion in the form of net base-producing foods or alkalinizing salts could potentially prevent this acid-related loss of bone. Presently, data exists that support both the proponents as well as the opponents of this hypothesis. Recent literature reviews have tended to support either one side or the other. Assuming that the data cited by both sides is correct, we suggest a way to reconcile the discordant findings. This overview will first discuss dietary acids and bases and the idea of changes in acid balance with increasing age, then review the evidence for and against the usefulness of alkali therapy as a treatment for osteoporosis, and finally suggest a way of reconciling these two opposing points of view.

Purpose

The purpose of this study was to determine the impact of food on gastric pH and the ability of over the counter betaine hydrochloride (BHCl) acid to reacidify gastric pH after food-induced elevations in gastric pH.

Methods

This open-label cross over clinical study (NCT02758015) included 9 subjects who were randomly assigned to one of 16 possible, 4-period cross-over sequences to determine the impact and relationship of food and gastric pH with acid supplementation. Subjects were administered various doses (1500 mg, 3000 mg and 4500 mg) of betaine hydrochloride (BHCl) to determine the ability of acid supplementation to reacidify gastric pH after the elevation of gastric pH caused by the ingestion of food.

Results

Following the administration of food and the resulting elevation in gastric pH, time to return to baseline gastric pH levels without acid supplementation was 49.7 ± 14.0 min. Administering 4500 mg of BHCl acid in capsules was able to reacidify gastric pH levels back to baseline following the administration of food in approximately 17.3 ± 5.9 min. AUC_pH of each treatment were similar and not statistically different. Mean max pH following the administration of food was 3.20 ± 0.55.

Conclusion

The ability of food to elevate and maintain gastric pH levels in the presence of acid supplementation was made evident throughout the study. A 4500 mg dose of BHCl was required to reacidify gastric pH after the administration of food. This study details the difficulty faced by clinicians in dosing a poorly soluble, weakly basic drug to patients receiving acid reducing agents where administration with food is recommended to avoid gastric side effects.

Trial registration

https://clinicaltrials.gov/ct2/show/NCT02758015.