Metabolic syndrome may increase prevalence of kidney stones

The researchers, therefore, suggest that controlling MetS may help lower the incidence of kidney stones. MetS is a collection of clinical syndromes which are closely connected to hyperglycemia, obesity, dyslipidemia, and hypertension. It is a group of risk factors that are linked to metabolism.

Kidney stone is a common urological disease that affects people worldwide. There has been a gradual rise in the incidence of kidney stones in recent years with the great changes in people's diet structure and lifestyle, with a global prevalence of 7.2–7.7%. Several studies have shown that metabolic syndrome, obesity, race, and age were all associated with an increased prevalence of kidney stones.

At the same time, there has been a year-by-year increase in MetS prevalence. Some studies have shown a strong link between metabolic syndrome and kidney stones, and each component of MetS raised the risk of kidney stones separately. Despite this, not many large-scale cross-sectional studies have linked MetS and kidney stones.

Therefore, Liangli Chen, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, China, and colleagues conducted a cross-sectional study to determine the relationship between MetS components and kidney stones in a health screening population.

For this purpose, the researchers recruited subjects who underwent health checkups in the Health Promotion Centre of Sir Run Run Shaw Hospital of Zhejiang University between January 2017 and December 2019. It included 74,326 participants aged 18 or older, including 56.1% of men.

The diagnostic criteria of MetS were based on the joint statement of the International Diabetes Federation (IDF) and other associations on MetS in 2009.

The study led to the following findings:

• There were 33.4% of patients with MetS and 2.7% of patients with kidney stones.
• The prevalence of kidney stones was 3.3% in subjects with MetS and 2.4% in subjects without MetS.
• The odds ratio for kidney stones in MetS patients was 1.157.
• The prevalence of kidney stones showed a statistically significant trend of gradual increase as the number of MetS components increased.
• Among the components of MetS, elevated waist circumference, reduced high-density lipoprotein cholesterol (HDL-C), and elevated fasting blood glucose (FBG) were independent influencing factors of kidney stones, with odds ratios of 1.205, 1.222 and 1.335, respectively.

"Our findings revealed that MetS is an independent risk factor for kidney stones, and kidney stones risk increased with the increase in the number of MetS components," the researchers wrote. "Among the five MetS components low HDL-C, elevated waist circumference, and elevated blood glucose were independent influencing factors of kidney stones."

"Therefore, more attention should be paid to the treatment and prevention of MetS, which may be helpful to correct urinary tract metabolic abnormalities, thus leading to prevention of kidney stones," they concluded. "Future large-scale cohort studies will be done to test this hypothesis."

Reference:

Chen L, Zhang J, Shen K, Zhu Y, Zhang J, Pan J, Chen L. Kidney stones are associated with metabolic syndrome in a health screening population: a cross-sectional study. Transl Androl Urol. 2023 Jun 30;12(6):967-976. doi: 10.21037/tau-23-51. Epub 2023 Jun 9. PMID: 37426600; PMCID: PMC10323452.

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