Night Time Use of Thiazide Diuretics for Improved Reduction in Stone Risk in Stone Formers With Elevated Urine Calcium

Sponsor

VA New York Harbor Healthcare System (U.S. Fed)

Overall Status

Unknown status

CT.gov ID

NCT02711670

Collaborator

(none)

Enrollment

Location

Arm

Duration (Months)

0.3

Patients Per Site Per Month

Study Details

Study Description

Brief Summary

Thiazide diuretics will be more effective in lowering urine calcium excretion if taken at night as compared to the daytime. It will therefore be more effective in reducing kidney stone recurrence in nephrolithiasis patients with elevated urine calcium who are known to have increased risk of kidney stones at night time.

Condition or Disease	Intervention/Treatment	Phase
Kidney Stones	Drug: chlorthalidone Drug: Hydrochlorothiazide	N/A

Detailed Description

The study will be divided into three phases for every single patient, investigators will study 15-20 stone formers who have previously documented elevated urine calcium excretion, with a plan to measure their urine chemistries at baseline (if they currently use thiazide diuretics, they will come off of their respective thiazide for a 7-day washout period). Investigators will ask them to collect urine samples in two 12-hour intervals: on awakening, the 1st sample starts to before supper; 2nd sample begins after dinner and extends overnight with fasting after dinner, These measurements will be used as controls. Then patients will be started back on diuretics (25mg of chlorthalidone for the primary study; pending the results this may be repeated with 25mg of hydrochlorothiazide as a second substudy) which they will take in the daytime; after a 6-day acclimation period, two 12-hour urine samples will be collected as in the washout period. For the third study period, the patients will then begin taking the thiazide after dinner. After a 6-day acclimation period, the third set of urine collections will be done.

Study Design

Study Type:

Interventional

Anticipated Enrollment :

10 participants

Allocation:

N/A

Intervention Model:

Single Group Assignment

Masking:

None (Open Label)

Primary Purpose:

Prevention

Official Title:

Night-time Use of Thiazide Diuretics for Improved Reduction in Stone Risk in Stone Formers With Elevated Urine Calcium

Study Start Date :

Feb 1, 2014

Anticipated Primary Completion Date :

Jun 1, 2017

Anticipated Study Completion Date :

Jun 1, 2017

Arms and Interventions

Arm	Intervention/Treatment
Experimental: thiazide Stone formers History of calcium containing kidney stones, hypercalciuria on previous urine tests, no kidney disease, not pregnant/lactating	Drug: chlorthalidone Drug: Hydrochlorothiazide

Arm

Intervention/Treatment

Experimental: thiazide

Stone formers History of calcium containing kidney stones, hypercalciuria on previous urine tests, no kidney disease, not pregnant/lactating

Drug: chlorthalidone

Drug: Hydrochlorothiazide

Outcome Measures

Primary Outcome Measures

Change in excretion and supersaturation of urine calcium oxalate / phosphate [1 week]

Eligibility Criteria

Criteria

Ages Eligible for Study:

18 Years to 80 Years

Sexes Eligible for Study:

All

Accepts Healthy Volunteers:

Inclusion Criteria:

Patients with recurrent calcium kidney stones (at least 2 episodes) and either a higher urine calcium excretion (urine Ca >200 mg/d or > 4 mg/kg body weight) or,
In patients who currently take a thiazide diuretic, a history of elevated urine calcium prior to medication use;
Also capable of signing consent and doing 24-hour urine collections repeatedly.

Exclusion Criteria:

Patients with primary hyperparathyroidism, renal tubular acidosis, chronic kidney disease (serum creatinine > 1.5 mg/dl), inflammatory bowel disease, gout,
Patients taking thiazides with a history of hypertension,
Patients with baseline systolic blood pressure less than 110mmHg