Association between metabolic syndrome and nephrolithiasis in an inpatient population in southern Italy: role of gender, hypertension and abdominal obesity.

BACKGROUND: Metabolic syndrome (MetS) and nephrolithiasis (NL) are quite common disorders. While some of the components of MetS have been proposed as precursors of NL in population studies, no data are available about the possible association between NL and MetS as such. The primary objective of the study was to evaluate the relationship between MetS and NL. The secondary outcome was to examine the relationship between MetS single constitutive elements and NL considering the strict correlation occurring among these factors. METHODS: We studied 2132 Caucasian inpatients of the 'Spinelli' Hospital in southern Italy (males/females = 0.95; mean age 63.8 +/- 15.8 years; body mass index 26.1 +/- 3.9 kg/m(2)). The MetS diagnosis was performed according to the Heart Association/National Heart, Lung, and Blood Institute criteria. The presence of NL was assessed by ultrasound examination of the kidneys and upper urinary tract. RESULTS: Seven hundred twenty-five subjects (34.0%) had a positive diagnosis of MetS. Two hundred twenty subjects (10.3%) had echographic evidence of NL, while 199 subjects reported a past history of NL (9.3%). The presence of MetS, as well as the male sex, and the occurrence of a previous episode of NL (in male subjects only) were each independently related to echographic evidence of NL. Among the individual components of MetS, high blood pressure and abdominal obesity (in female individuals only) were also independently related to echographic evidence of NL. CONCLUSIONS: MetS is significantly associated with echographic evidence of NL. A gender-related difference in the clinical expression of NL was also observed.

Metabolic syndrome and nephrolithiasis: can we hypotize a common background?

Metabolic syndrome and nephrolithiasis are quite common disorders presenting similar epidemiological characteristics. Belonging to genetic, environmental and hormonal interaction, they have high incidence and prevalence in the adult population of industrialised countries and are characterised by a high level of morbidity and mortality if not adequately identified and treated. Despite metabolic syndrome is considered a fundamental risk factor for chronic kidney diseases, is not actually known whether it is associated with nephrolithiasis beyond the effect of its individual components, in particular obesity, glucose intolerance, and hypertension. In this paper, the possible pathogenetic links between metabolic syndrome and nephrolithiasis will be presented and discussed.