Seasonal Variations and Factors that Influence Diverticular Bleeding in the United States of America.

Background: Seasonal variation in hospitalizations for diverticulitis has a sinusoidal pattern, peaking in summer. Little is known about seasonal, regional trends, and risk factors associated with hospital admissions regarding diverticular bleeding in the United States.

Study design: Cross-sectional population database review using the healthcare cost and utilization project's national inpatient sample.

Methods: Patients that had diagnoses of diverticulitis with bleeding or diverticulosis with bleeding admitted from January 1, 2015, through December 31, 2017, were identified and stratified by month and season. Then, the potential effects of region, age, gender, race, and patient risk factors on seasonal admissions for diverticular bleeding were explored, and data were analyzed in SAS and presented in Excel using chi-square and Kruskal-Wallis for categorical and continuous variables, respectively.

Results: Of the 54191 hospitalized cases for diverticular bleeding, the peak and the lowest seasons were spring and summer (25.5% vs. 24.2%, P<0.0001). A significant seasonal pattern in comorbidities was also identified, and those with diabetes (P<0.0001), hypertension (HTN) (P<0.0001), obesity (P<0.0001), and those on anticoagulants (P=0.016) all had more bleeding events in the spring. This was noted across US regions, gender, race, and age. Eventually, the southern region had the most admissions for diverticular bleeding at 40.9% (P<0.0001).

Conclusion: A better understanding of these seasonal and regional trends may provide a mechanism to identify a potential trigger for diverticular bleeding events. This helps identify individuals at greatest risk for hospitalization, as well as prepare hospitals to allocate supplies appropriately during the seasons.