This study presented the clinical course of 221 patients with CDB over 13 years in a tertiary referral center. The recurrence rate was as high as 23%. CCI ≥ 4 was found to be significantly associated with an increased risk of rCDB.
The incidence of CDB is increasing because of the increase in the incidence of colonic diverticulosis, elderly population, and antithrombotic agent use.[3] Approximately 70–90% of diverticular bleeding events spontaneously stop, complicating the definite diagnosis of diverticular bleeding.[15–17] In our study, only 25% of the patients were diagnosed with definite CDB, which was similar to proportions in previous studies (19–42%),[6, 18, 19] and CDB spontaneously stopped in 80% of the patients. Despite this, about 25% of the patients with CDB experienced hypovolemic shock at admission, which was also similar to that in a previous study (25.6%).[7] Moreover, two patients with CDB died at first admission (one with CDB and another with myocardial infarction). Therefore, any changes in symptoms or vital signs should be closely monitored and adequate resuscitation should be provided for all patients with CDB.
While left-sided colonic diverticulosis is more common in Western countries, right-sided colonic diverticulosis is more common in Asia.[18, 20–22] CDB is more commonly right-sided,[23, 24] and our study showed similar results.
Endoscopic hemostasis can achieve a high rate of active bleeding control[25, 26] and is typically considered the first-line treatment for CDB management.[27, 28] In this study, 75% of patients had undergone urgent colonoscopy examination within 24 hours. Although aggressive colonoscopic evaluation was performed as the first evaluation, endoscopic intervention was performed in only a third of the patients. A literature review reported an endoscopic hemostasis rate ranging from 20.8 to 32.8% in Western countries [29, 30] and 16.8 to 34.1% in Eastern countries,[31, 32] which were similar to the rates in our study. Angiographic treatment and surgical resection can be the other modalities used if endoscopic hemostasis fails.[33, 34] In our study, radiological intervention was performed in 11 (5.0%) patients and surgical intervention in 2 (0.9%).
In our study, the 1-year incidence of rCDB was 12.3%. In other studies, the 1-year incidence of rCDB varied between 4% and 35%.[4–7] Although NSAIDs, steroids, antithrombic agents, obesity, hypertension, and CKDs are risk factors for rCDB, each study showed inconsistent results,[4–6, 35] suggesting that considering the overall patient condition, rather than each variable, is necessary.
We used the CCI score to reflect the overall status of comorbidities. The CCI score was calculated according to the severity of various underlying diseases and was originally developed to analyze the 1-year mortality of hospitalized patients.[8] Recently, it has been used to predict the prognosis in various patient groups,[9–12, 36] with high CCI scores becoming a risk factor for severe CDB.[37] In this study, the CCI scores of the two patients who died at first admission were 4 and 5. A high CCI score is also a risk factor for rCDB.[38]
In our study, the incidence of rCDB was 2.7 times higher in patients with CCI scores ≥ 4 than in those with CCI scores < 4, after adjusting for several known risk factors, such as age, sex, medication intake, hemostasis, and location of CDB. Furthermore, we showed a significant increase in mortality even in patients with CDB with CCI scores of ≥ 4. A CCI score of ≥ 4 was usually confirmed in patients with multiple or serious comorbidities, suggesting that multiple comorbidities affect the incidence of rCDB in patients.
In this study, CDB-related death occurred in two patients, and the overall mortality rate was twice as high in patients with rCDB compared to that in patients without rCDB. Although CDB itself was not the immediate cause of death, increased hospitalization and morbidity due to CDB may have affected the increase in mortality.
Our study had two limitations. First, this was a retrospective cohort study conducted at a single referral center. However, a larger number of cases were evaluated in this study than in previous studies. Second, this study did not reflect the effects of variable endoscopic hemostatic methods, such as endoscopic band ligation, endoscopic detachable snare ligation, use of topical hemostatic agents, and over-the scope clip.[31, 39–41] We typically performed endoscopic hemostasis using EC or endoscopic injection therapy. Recent studies showed that endoscopic band ligation was more helpful in decreasing early rCDB.[18, 34]