Circadian Rhythmicity in the Urinary Excretion of Calcium, Oxalate, Uric Acid, and Inorganic Phosphorus in Stone Formers and Their Cohorts in Northwestern India

Environmental factors such as diet, climate, geographical factors, and fluid intake have an important role in the etiology of urolithiasis (1). Circadian rhythmicity in the urinary volume and excretion of creatinine (Cr), oxalate (Ox), glycolic acid, phosphate (Pi), uric acid (UA), sodium, potassium, chloride, and 17-keto steroids have been reported in healthy adults. Cohorts of stone formers who belong to the same ethnic group, share the same food habits, and are exposed to similar climatic conditions may be equally susceptible to stone disease which, possibly, may be present in the form of subtle biochemical changes. The present study investigates the circadian fluctuations in stone formers and cohorts of stone formers in an endemic area in northwestern India.