Kidney Calculi, Calcium Oxalate Kidney Stones, Calcium Phosphate Kidney Stones
Conditions
Keywords
Kidney stone
Brief summary
The aim of this randomized placebo-controlled double-blind crossover clinical trial is to test the ability of a traditional tea made from the leaf of the Bryophyllum pinnatum (B. pinnatum) plant in decreasing urinary calcium content in patients with recurrent calcium-based kidney stones.
Detailed description
Background and Rationale: Kidney stones are hard deposits that consist of calcium complexed with phosphate or oxalate, thus, high urinary calcium content is a major risk factor. The precipitation of calcium can arise from various mechanisms including the aggregation of urinary calcium crystals from impaired transport along the nephron, reduced urinary inhibitors (e.g. citrate), and increased oxidative stress and inflammation. Large stones can block the drainage system of the kidney, causing acute severe pain and inflammation. Recurrent kidney stones can lead to sustained inflammation resulting in a progressive loss of renal function. As the global incidence and economic burden continues to rise there is a undisputed medical need to find preventative measures. Thiazide diuretics have been fundamental in pharmacological recurrence prevention for the past 60 years. The recent NOSTONE trial (NCT03057431) revealed that the most widely prescribed and best studied thiazide, hydrochlorothiazide, did not reduce the incidence of stone recurrence. There remain significant barriers to kidney stone treatment including high treatment costs, side effects, and the difficulty in achieving long-term dietary and lifestyle changes. Therefore, many patients risk recurrent episodes. New innovative approaches are needed to prevent kidney stone formation. The leaves of Bryophyllum pinnatum are used to treat a variety of ailments, including the prevention and treatment of kidney stones in various formulations. In a rat kidney stone model, aqueous, alcoholic, and non-alcoholic extracts of B. pinnatum leaves prevented the formation and reduced the size of kidney stones. In an uncontrolled trial, patients with renal stones treated with B. pinnatum juice either passed their stones or showed a reduction in the size of their stones. Despite its established use in other countries, B. pinnatum tea has not undergone rigorous scientific or clinical evaluation. Our lab characterized and standardized the formulation of the tea which revealed anti-urolithiatic activity along with antioxidant and anti-inflammatory properties. A combination of these effects may be what is beneficial in the prevention of recurrent kidney stones.
Interventions
COMBINATION_PRODUCTBryophyllum pinnatum tea
24 g of B. pinnatum leaves boiled in 250 mL of water for 61 minutes sweetened with 1/2 teaspoon of sugar
COMBINATION_PRODUCTPlacebo tea
250 mL of water boiled with 3 g of wheat-bran for 5 minutes sweetened with 1/2 teaspoon of sugar
Sponsors
Indra Gupta
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
PREVENTION
Masking
QUADRUPLE (Subject, Caregiver, Investigator, Outcomes Assessor)
Masking description
Both the B. pinnatum tea and the placebo tea will be provided in identical dark thermoses with a lid. The placebo wheat-bran tea tastes and looks identical to the treatment, B. pinnatum tea.
Intervention model description
Each participant will be assigned to one of the following groups: Group 1: Drink wheat-bran tea (placebo) first then, B. pinnatum tea (treatment). Group 2: Drink B. pinnatum tea first (treatment), then wheat-bran tea (placebo). The placebo and the treatment are sweetened with 1/2 teaspoon of sugar.
Eligibility
Sex/Gender
ALL
Age
18 Years to 70 Years
Healthy volunteers
No
Inclusion criteria
* 18-70 years of age at time of study enrollment * 1 calcium-based stone event within a 3-year interval and/or hypercalciuria on a 24h urine collection (\>5 mmol/day) * They had an ultrasound or CT imaging within the previous 6 months which showed no evidence of current obstructive kidney stone * Adhering to the stone prevention diet (high water/low salt/low protein intake) for at least one month prior to enrollment in study but not taking any stone-preventing medications * Agrees to maintain current lifestyle habits and avoid taking new supplements during the study period
Exclusion criteria
* Patients with secondary causes for calcium stone formation (primary hyperparathyroidism, inflammatory bowel disease, hyperuricosuria, and cancer) * Patients who are pregnant or nursing or who are trying to become pregnant * Currently consuming B. pinnatum or any natural health product containing polyphenols * A known intolerance or allergy to the plant B. pinnatum * Currently taking stone-preventing medication * Gluten intolerance or allergy
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Reduction in 24-hour urine calcium excretion | 24 hours after ingestion (day 2 and day 11) | After ingestion of the placebo and treatment, participants will begin a 24 hour urine collection. Urinary calcium levels will be reported as mmol/day. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Adverse effects | 24 hours after ingestion (day 2 and day 11) | Partipants will be asked if they experience any adverse effects immediately after and 24 hours after ingestion. |
| Increase in 24-hour urine citrate excretion | 24 hours after ingestion (day 2 and day 11) | After ingestion of the placebo and treatment, participants will begin a 24 hour urine collection. Urinary citrate levels will be reported as mmol/day. |
Countries
Canada
Outcome results
None listed