Outcomes of Patients With Diverticulitis and Risk Factors for Recurrence
Outcomes of Patients With Diverticulitis and Risk Factors for Recurrence
In the Emergency Department (ED), patients with acute diverticulitis usually present with
 acute abdominal pain. Sometimes, or mostly, it is an exclusive diagnosis, meaning that the
 diagnosis would be made after other emergent and acute abdomens are excluded. The recurrent
 diverticulitis cost medical burden. The studies focusing on potential risk factors of
 recurrent diverticulitis, especially for those after an episode of acute diverticulitis, are
 limited.
Diverticular disease of the colon is common in industrial countries and has significant
 impact on patient health as well as health care cost. It is common in both Western countries
 and some Asian countries. For example, in the past, colonic diverticulosis was rare in Japan;
 with detection rates as low as approximately 2% in 1960. The detection rate increased to
 approximately 20% in the 1980s and 1990s. Studies have reported that increasing rates of
 diverticulosis are caused by westernization of the diet in Asian countries and are becoming a
 medical concern. Diverticular disease-associated hospital admissions have risen steeply in
 the recent past, which are not completely accounted for by the increasingly aging population
 of western countries. Approximately 130,000 hospitalizations occurring every year in the
 United States are attributable to diverticular disease. An analysis of the age-adjusted
 hospitalization rate of diverticulitis in the United States showed an increase from 62 per
 100,000 in 1998 to 76 per 100,000 in 2005. These admission rates increased most in younger
 patients (< 45 years old) and have remained unchanged in patients older than 65 years. In
 spite of low mortality rate in patients with acute diverticulitis, moderate to severe
 comorbidities occur in specific patient group.

 Painter and Burkitt hypothesized it in their article in 1960s and 1970s. They based their
 hypothesis on the observation that individuals in different geographic locations such as
 western industrialized countries versus those in developing countries were noted to have
 different rates of prevalence. They postulated that those in industrialized nations tended to
 eat processed food that was low in fiber compared with individuals in Africa and Asia, where
 the disease was previously unknown.

 The USA Health Professional study showed a higher risk of diverticulitis in men with higher
 body mass index (BMI), waist-to-hip ratio and waist circumference [8]. Obesity also
 significantly increases costs associated with management of the disease and its complications
 [9]. The effect of obesity on the risk of recurrent diverticulitis is unknown.

 In the Emergency Department (ED), patients with acute diverticulitis usually present with
 acute abdominal pain. Sometimes, or mostly, it is an exclusive diagnosis, meaning that the
 diagnosis would be made after other emergent and acute abdomens are excluded. The recurrent
 diverticulitis cost medical burden. The studies focusing on potential risk factors of
 recurrent diverticulitis, especially for those after an episode of acute diverticulitis, are
 limited.

 This is a retrospective cohort study conduct from March, 2012 to September, 2018. The
 patients were recruited from National Taiwan University Hospital (NTUH), NTUH Hsin-Chu Branch
 (HCH), and NTUH Yun-Lin Branch. The expected case number in these three hospital is 1000,
 400, and 300, respectively. We apply for waive of informed consent due to nature of
 retrospective medical record and minimal intervention onto patients.
Inclusion Criteria:

 -  the patients who (a) visited ED during March, 2012 and September, 2018; (b) were
 diagnosed as diverticulitis by computed tomography (CT); (c) were aged over 20.

 Exclusion Criteria:

 -  the patients who (a) received CT at other hospital and lost image; (b) lost the
 follow-up after index ED admission.