Method of determing excretion of sodium and other analytes
AssigneeCornell University
InventorsSamuel J. Mann, Linda M. Gerber
Life of this patent
Estimating the term…
Abstract
Methods and kits of the invention are useful for calculating 24-hour excretion of sodium without the need to collect urine for 24 hours.
Claims56
A method of determining a subject's 24-hour urinary excretion of an analyte from a single sample of the subject's urine, comprising:
- measuring the analyte concentration in the single urine sample;
- measuring creatinine concentration in the single urine sample;
- using the subject's age, gender, race, weight, muscle mass, lean body mass, muscle mass, adiposity, physical activity, or a combination thereof, to select a normalized 24-hour creatinine excretion value from an array of normalized 24-hour creatinine excretion values, wherein each normalized 24-hour creatinine excretion value is an estimated mean of observed 24-hour urine creatinine concentrations for a population of persons of similar age, gender, race, weight, muscle mass, lean body mass, muscle mass, adiposity, and/or physical activity;
- and
- using the normalized 24-hour creatinine excretion value, the measured analyte concentration, and the measured creatinine concentration to determine the 24-hour urinary excretion of analyte for the subject.
A method of determining a subject's 24-hour urinary excretion of sodium from a single sample of the subject's urine, comprising:
- measuring chloride concentration in the single urine sample;
- measuring creatinine concentration in the single urine sample;
- using the subject's age, gender, race, weight, muscle mass, lean body mass, muscle mass, adiposity, physical activity, or a combination thereof, to select a normalized 24-hour creatinine excretion value from an array of normalized 24-hour creatinine excretion values, wherein each normalized 24-hour creatinine excretion value is an estimated mean of observed 24-hour urine creatinine concentrations for a population of persons of similar age, gender, race, weight, muscle mass, lean body mass, muscle mass, adiposity, and/or physical activity;
- and
- using the normalized 24-hour creatinine excretion value, the measured chloride concentration, and the measured creatinine concentration to determine the 24-hour urinary excretion of sodium for the subject.
A method of improving the accuracy of determining 24-hour urinary excretion of sodium by a subject from a single urine sample, comprising:
- measuring creatinine concentration and chloride concentration in a single urine sample obtained from a subject in late afternoon before consuming a meal;
- using the subject's gender, race and weight to select a normalized 24-hour creatinine excretion value from an array of normalized 24-hour creatinine excretion values, wherein each normalized 24-hour creatinine excretion value in the array is an estimated mean of observed 24-hour urine creatinine concentrations for a population of persons with the subject's gender, race and weight;
- and
- determining the subject's 24-hour urinary excretion of sodium.
A kit for calculating 24-hour excretion of an analyte by a subject, the kit comprising:
- (a) a container for holding a single urine sample;
- (b) a device for measuring the analyte concentration in the single urine sample;
- (c) a device for measuring creatinine concentration in the single urine sample;
- and
- (d) instructions comprising a first nomogram listing normalized 24-hour creatinine excretion values for distinct populations of subjects, where the normalized 24-hour creatinine excretion values vary depending upon the populations' age, gender, race, weight, lean body mass, muscle mass, adiposity, physical activity, or a combination thereof, and
An article of manufacture comprising an array of normalized 24-hour creatinine excretion values and instructions for converting a subject's spot urine analyte concentration and the subject's spot creatinine concentration to a normalized 24 hour analyte concentration for the subject.
A computer-readable medium having stored thereon an array of normalized 24-hour creatinine excretion values and a program of instructions executable by a processor to convert a subject's urine sample analyte concentration value, and the subject's urine sample creatinine concentration to a calculated 24 hour analyte concentration for the subject.
Dependencies are inferred from the claim text.