Hypertriglyceridemia is associated with increased risk for stone recurrence in patients with urolithiasis.
Objective: To assess the influence of dyslipidemia on urinary lithogenic metabolites and stone recurrence in stone formers.
Methods: We retrospectively selected 321 patients with urolithiasis who had been followed up for >24 months between 2004 and 2009. Fasting blood samples were taken, and serum lipid profiles were measured. All subjects also underwent 24-hour urinary metabolic evaluation and stone analysis. The radiographic appearance of new stones was defined as stone recurrence.
Results: There was no significant correlation between lipid profiles and 24-hour urine metabolites (all P >.05). Stone formers with hypertriglyceridemia had significantly higher urinary calcium, sodium, uric acid, magnesium, and potassium excretions. Only in a subgroup of uric acid stone, hypertriglyceridemia was significantly associated with decreased urinary pH. Those with low high-density lipoprotein (HDL) cholesterolemia had higher urinary sodium, magnesium, and potassium excretions, whereas those with high low-density lipoprotein (LDL) cholesterolemia had lower urinary sodium excretion. Stone analysis revealed that uric acid stones were more commonly found in patients with hypertriglyceridemia and low-HDL cholesterolemia. After a median follow-up of 35.0 months, 109 patients (34% of cohort) had stone recurrence. Stone recurrence was more common in the hypertriglyceridemia group compared with the normal triglyceridemia group (45.9% vs 29.7%; P = .005). The multivariate Cox regression model revealed that hypertriglyceridemia is associated independently with stone recurrence (hazard ratio, 1.857; 95% confidence interval, 1.211-2.847; P = .005). Kaplan-Meier curves showed similar results.
Conclusions: Our study showed that serum lipid profile is associated with urine metabolic alterations. More importantly, hypertriglyceridemia is independently associated with increased risk for stone recurrence in patients with urolithiasis.