Comorbidity and socio-demographic factors associated with renal lithiasis in persons aged 40 to 65: A cross-sectional study.

BACKGROUND AND OBJECTIVE: Renal lithiasis is one of the most important urological diseases. It seems to be related to different socio-demographic and climatic factors, lifestyle and pre-existing comorbidity. The aim of this study was to examine the relationship between socio-demographic variables, certain risk factors and chronic diseases and the renal lithiasis.

PATIENTS AND METHOD: A cross-sectional population-based study was carried out, selecting the Spanish population aged from 40 to 65 years, combining 2 random samples (PreLiRenA and PreLiRenE studies). Data were collected by personal telephone surveys, gathering information on socio-demographic variables and perceived morbidity. Data on annual average temperatures in each Spanish region were also collected. A bivariate and multivariate analysis was performed.

RESULTS: A total of 4,894 subjects were surveyed; 51.3% were women; 25% were aged 40-45 years, 36% had primary school education and 31.4% were of low social class. The overall prevalence of renal lithiasis was 15.0% (95% confidence interval [95% CI] 14.5-15.5). By means of multivariate analysis, the variables that showed a strong statistical relationship with the presence of renal lithiasis were: older age (61-65 years; OR=1.39; 95% CI 1.06-1.80), high social class (OR=1.98; 95% CI 1.29-2.62), family history of renal lithiasis (OR=2.22; 95% CI 1.88-2.65), high blood pressure (OR=1.68; 95% CI 1.39-2.02) and overweight/obesity (OR=1.31; 95% CI 1.12-1.54). A correlation was observed between renal lithiasis and average annual temperatures in the Spanish regions (r=0.59; P=.013).

CONCLUSIONS: A relationship was observed between renal lithiasis and older age, belonging to higher social classes, the existence of a family history of urolithiasis, and hypertension and overweight or obesity. The prevalence of renal lithiasis is greater in warmer climate zones.