Associations between clinical, biochemical, and nutritional factors in kidney stone formation and recurrence

This case-control study investigated the relationship between dietary habits and kidney stone development and recurrence at District Headquarters (DHQ) Hospital in Pakistan over a 12-month period. The study included 600 patients with a history of kidney stones and 50 healthy controls aged 18-65. Dietary patterns were evaluated using a 24-hour dietary recall and a semi-quantitative food frequency questionnaire (FFQ), with emphasis on oxalates, calcium, animal protein, fluid consumption, and other nutritional factors. Urinary and serum biomarkers-such as calcium, oxalate, citrate, sodium, potassium, pH, phosphate, magnesium, uric acid, and parathyroid hormone (PTH)-were also analyzed. Results indicated strong dietary links to kidney stone risk. Increased oxalate intake (*p* = 0.004), insufficient calcium consumption (*p* = 0.017), and high animal protein intake (*p* = 0.021) were significantly associated with stone formation. Elevated serum uric acid (> 6 mg/dL) was particularly linked to uric acid stones (*p* = 0.008). Urinary analysis revealed common abnormalities, including hyperoxaluria (80%), hypocitraturia (65%), and hypercalciuria (42%). Additionally, altered serum calcium and PTH levels in stone formers suggested secondary hyperparathyroidism as a potential contributing factor. Multivariate logistic regression identified several significant risk factors: high oxalate intake, low fluid consumption, hypocitraturia, and increased serum calcium and uric acid levels. These findings highlight the critical role of diet and metabolic factors in kidney stone formation and recurrence. Further studies are required to establish whether preventive strategies focusing on diet modification and biochemical management may help reduce the incidence and recurrence of kidney stones.