Prevalence of and Risk Factors for Incidental Colonic Diverticulosis

The true prevalence and pathogenesis of diverticulosis is poorly understood. Risk factors for diverticulosis are presently unclear, with most clinicians attributing its development to years of chronic constipation. Previous studies have been limited by their failure to include young, ethnically diverse patient populations.

Patients who presented to the emergency department of our hospital from January-September 2019 and underwent abdominal computerized tomography (CT) scan for the evaluation of appendicitis were included. CT's were reviewed for the presence of diverticulosis. Risk factors for diverticulosis were determined for two age groups: >40 and ≤ 40.

A total of 359 patients were included in the study. The median age was 38.57.1% were male. 81.6% were Hispanic. 43.5% had colonic diverticulosis on CT. 198 patients (55.1%) were ≤ age 40. The rate of diverticulosis in this group was 35.3% (n = 70). Those with diverticulosis were not significantly older (median age 29 versus 27, P = 0.061) but had a higher median body mass index (BMI) (28.4 versus 25.3, P = 0.003) compared to those without diverticulosis. On multivariate analysis, no characteristics were associated with the presence of diverticulosis for this group. Over age 40, 53.4% of patients (n = 86) had diverticulosis. Patients with diverticulosis were more likely to be Hispanic (95.3% versus 73.3%, P ≤ 0.001), less likely to be Asian (2.4% versus 16.0%, P = 0.004), had a higher median BMI (28.7 versus 25.5, P ≤ 0.001), and were more likely to use alcohol (30.2% versus 14.7%, P = 0.024) than those without diverticulosis. On multivariate analysis, characteristics associated with the presence of diverticulosis were BMI >30 (odds ratio OR 2.22, 95% confidence interval CI 1.03-4.80), Hispanic ethnicity (OR 10.05, 95% CI 1.74-58.26), and alcohol use (OR 3.44, 95% CI 1.26-9.39).

There was a higher rate of asymptomatic diverticulosis in the <40 cohort than previously reported in the literature. Obesity, alcohol use, and Hispanic ethnicity were associated with the presence of diverticulosis in patients > age 40, but no risk factors for diverticulosis were identified for patients ≤ age 40, suggesting that diverticular pathogenesis may differ by age. Constipation was not a risk factor for diverticulosis in either age group. The data regarding the prevalence of diverticulosis in Hispanic patients is lacking and should be the focus of future inquiry.