EPIDEMIOLOGY OF RENAL LITHIASIS
Renal lithiasis is common and increasing in all industrialized countries. The first population studies are late. They started in the years 1970-1980 in Scandinavia. Then other studies came along. The main epidemiological elements retained are as follows :
In Scandinavia in the 1980s, 19% of men over 60 had a history of lithiasis.
In Germany, in 1980, kidney stones as a whole progressed by 17% ; these figures were confirmed in the early 2000s.
In Italy the prevalence affects at least 10% of the population with a clear prevalence in the south.
In 2001 a Spanish study showed an incidence of 2.66 per 1000 inhabitants, ie a prevalence greater than 10% in subjects over 60 years old.
In the United States there was an increase of nearly 62% in the 80s and 90s. The regional disparity is real with an increased prevalence in the south. In Tennessee it can affect nearly 18% of the population.
Finally in Japan between 1965 and 1995 the prevalence of lithiasis doubled.
In France the prevalence is 10% of the adult population. The recurrence rate is 50% with an average lull of 3.5 years between two episodes. One third of patients have at least three lithiasis episodes in their lifetime. The ratio M / F 2.07 approximately. In other industrialized countries, this ratio tends to decrease in favor of women.
Evolution of the composition of calculations over the last 20 years in France
The composition differs in men and women between two decades (1990-1999 vs 2000-2009)
Calcium Oxalate and Uric Acid stones are more common in men while calcium phosphate stones are more common in women.
However in humans, Weddelite calculations have tended to regress between two decades (25.3 vs 23.4%) while Uric Acid calculations have increased (+ 23% between two decades).
In women, Brushite stones (recurrent form) have increased from 0.4 to 1%, while Phospho-Ammoniaco-Magnesian stones have regressed.
The lithiasis associated with the crystallization of the drug has considerably regressed in humans.
Finally, the calculations developed on Randall's plate (intra-tubular phospho-calcium deposits) also tend to decrease.
Influence of age
In young men weddelite predominates (45%) suggesting a phenomenon of hypercalciuria. Beyond 30 years, Whewellite increases and peaks at 59% in the 50-59 age bracket. Finally, Uric Acid peaks at 30% in those over 70 years old while it is only 1% in those under 30 years old.
In women, Whewellite is the predominant form in all age groups with a peak frequency of 53.9% between 40 and 49 years. Uric acid represents 20% after 70 years.
Overweight, Obesity and Metabolic Syndrome
Overweight
Weight gain has been constant in recent years in the French population with an obesity prevalence of around 15%. At the same time, there is a significant proportion of obese subjects in female lithiasics (18.9%) not found in men (11.4%). This suggests that women are more sensitive to the lithogenic consequences of obesity. The prevalence in the United States of lithiasis is higher in overweight or obese subjects compared to subjects of normal weight.
In type II diabetics the prevalence of lithiasis is higher than in the general population. The proportion of uric acid stones is higher than in obese non-diabetic patients, especially in women.
Genetic causes
Renal lithiasis induced by monogenic hereditary diseases are relatively rare but often severe, hence the importance of diagnosing them early. Renal function is often impaired due to the evolution of these pathologies.
