Diverticulosis is a disease in which small pouches form in the lining of the colon. If these pouches become inflamed, the painful and potentially serious condition known as diverticulitis occurs. Previous studies have reported that up to 25% of diverticulosis patients will develop diverticulitis. UCLA just released the results of a 15-year study that found that the risk of developing diverticulitis is significantly lower and that the age at which the disease is first diagnosed affects the risk of diverticulitis. The UCLA researchers published their findings in the December 2013 issue of the journal Clinical Gastroenterology and Hepatology.
In the US, diverticular disease accounts for more than 300,000 hospital admissions, 1.5 million inpatient care days and $2.4 billion in direct costs annually. Senior author Dr. Brennan Spiegel, an associate professor of medicine at the David Geffen School of Medicine at UCLA explained that the study will help inform patients with diverticulosis, particularly those diagnosed at a younger age, as well as their doctors, about the risks of developing acute diverticulitis. He said, “These colon pouches are commonly detected during colonoscopy, and patients wonder if they are important and what to do with them. In short, diverticulosis is not something to worry much about. Chances are low that something will happen.”
The researchers note that diverticulosis commonly develops in individuals as they age. More than 50% of individuals and almost 70% of those over 70 have the condition; however, most of these people do not experience any symptoms. If the pouches become inflamed, the individual experiences abdominal discomfort. Diverticulitis is usually treated with antibiotics; if the systems persist, surgery may be required.
Dr. Spiegel said explained that the previous research, which found a 25% risk of developing diverticulitis, was based on limited data that was acquired during a time period when colonoscopy was not a recommended screening procedure for the general population. He explained, “These risk figures have been widely quoted throughout the literature and appear in multiple research publications, prominent review articles, textbooks and public guidelines. “Because the data are from before the advent of routine colonoscopy, many cases of diverticulosis may have gone undiscovered, skewing the risk predictions.”
The study group comprised 2,222 patients from the Veterans Affairs Health System with chart-confirmed diverticulosis; they were followed for an average of 6.75 years. Among those patients, 95 of those 2,222 patients (4.3%) developed diverticulitis using a liberal definition of the condition, which did not require confirmation with a CT scan. When a stricter confirmation (i.e., CT scan or surgery) was applied, only 23 of the 95 patients (1%) developed diverticulitis. Dr. Spiegel noted, “With an aging population and greater use of colonoscopy for colorectal cancer screening, more and more people are going to be told they have diverticulosis. Patients often question the significance of this. If providers had more accurate information regarding the risk of diverticulosis complications, they then could make better decisions about the timing of interventions such as surgery.”
The investigators also found that individuals diagnosed with diverticulosis at a younger age are more likely to progress to diverticulitis than those diagnosed at an older age. Dr. Spiegel pointed out some limitations of the study. It was a retrospective (backward-looking), single-center study in a Veterans Affairs hospital where the patients were primarily Western and predominantly male. In addition, the investigators accessed administrative data to identify diverticulitis cases; thus, some cases may have been missed. However, the researchers did conduct extensive reviews of medical records to confirm the chart evidence of diverticulitis. Dr. Spiegel and his team plan further studies that will be comprised of different—and more diverse—populations.