# Causal Effects of Inflammatory Bowel Diseases on the Risk of Kidney Stone Disease

## TL;DR

This study finds that people with inflammatory bowel diseases are more likely to develop kidney stones, especially if they smoke or have had kidney stones before.

## Contribution

The study establishes a causal link between inflammatory bowel diseases and kidney stone disease, emphasizing risk factors like smoking and prior history.

## Key findings

- IBD patients had a significant risk of kidney stone disease, with 18.75% showing renal calculi.
- Smoking and prior kidney stone history were strongly associated with increased risk (p=0.006 and p<0.001).
- Crohn's disease was more prevalent than ulcerative colitis in the studied cohort.

## Abstract

Background: Inflammatory bowel diseases (IBDs), including Crohn's disease and ulcerative colitis, have been increasingly associated with kidney stone disease, posing significant health challenges globally.

Objective: This research sought to determine the causal relationship between kidney stone disease risk and inflammatory bowel disorders.

Methodology: This retrospective cohort study included patients with IBDs, such as ulcerative colitis or Crohn's disease, who were diagnosed at least 18 years of age. Information was gathered with an emphasis on patients having comprehensive medical histories and confirmed cases of kidney stone disease from January to December 2022. Medical records were retrospectively evaluated by trained staff to extract treatment information and clinical, radiological, and demographic data. To evaluate relationships, statistical analysis was carried out in SPSS software version 23 using Chi-square tests and descriptive statistics.

Results: The study included 320 patients diagnosed with IBDs, among which 198 (61.87%) had Crohn's disease, and 122 (38.13%) were diagnosed with ulcerative colitis. The cohort consisted of 140 females (43.75%) and 180 men (56.25%), with a mean age of 45.5 years. Regarding smoking, 113 people (35.31%) reported being smokers, whereas 207 people (64.69%) did not smoke. Additionally, 18 (5.62%) of the population had an underweight BMI, 136 (42.50%) had a normal BMI, 119 (37.19%) had an overweight BMI, and 47 (14.69%) had an obese BMI. Of the patients, 86 (26.88%) had a prior history of kidney stone disease, while 194 (60.62%) did not. Aminosalicylates were the most often used therapy modality for IBD in 189 (58.97%) of cases, followed by corticosteroids in 117 (36.56%) and immunomodulators in 93 (28.94%). Radiological examinations showed that renal calculi were present in 60 (18.75%) of patients, and kidney stones occurred in 40 (12.50%) of patients throughout the research period. The smoking status (p=0.006) and prior history of kidney stones (p<0.001) were the corresponding p-values for the significant results.

Conclusion: The study highlights an increased risk of kidney stone disease in IBD patients, particularly among smokers and those with a recurrent history of kidney stones. Of the 320 patients, 198 (61.87%) had Crohn's disease and 122 (38.13%) had ulcerative colitis, with a significant relationship found between kidney stones and both smoking (113 patients, 35.31%, p=0.006) and a prior history of kidney stones (86 patients, 26.88%, p<0.001). The findings emphasize the need for targeted preventive measures and close monitoring of these high-risk groups.