17-07-2025
Diverticular Disease Demystified: Myths, Risks & Modern Care
This transcript has been edited for clarity.
Hello. I'm Dr David Johnson, professor of medicine and chief of gastroenterology at Eastern Virginia Medical School and Old Dominion University in Norfolk, Virginia. Welcome back to GI Common Concerns .
Diverticulosis and diverticulitis are both incredibly common conditions. It's estimated that over 70% of people aged 80 or older who undergo colonoscopy will have diverticulosis. Approximately 4% of those will develop diverticulitis in their lifetime, and roughly 15% of those cases will be complicated disease.
Patients frequently ask what they can do to prevent diverticulitis or its recurrence, and the evidence to inform such conversations has evolved in recent years. This video provides an update on where we are presently.
Rethinking Dietary Causes
We've long emphasized diet in the management of diverticulosis and diverticulitis, and we considered it axiomatic that patients need to avoid corn, nuts, and seeds. However, a 2008 prospective cohort study in men challenged that approach, observing no association between consuming those dietary components and the risk of developing diverticulosis or diverticular complications.
Although that study was performed exclusively in men, the lifetime risk for diverticulitis is actually higher in women, at approximately 5% vs 3.1%, respectively.
A recent prospective analysis published in Annals of Internal Medicine from researchers at University of North Carolina adds important insights. It used validated dietary questionnaires in a large cohort of women [who had a sister with breast cancer but did not have breast cancer themselves at enrollment]. This allowed investigators to determine incident cases of diverticulitis over time, without the risk of recall bias.
Researchers identified more than 1500 incident cases of diverticulitis for nearly 415,000 patient years of follow-up. They reported no association between a primary diagnosis of diverticulitis and consumption of corn, nuts, or seeds, including fresh fruits with seeds. Similarly, there was no link between those foods and the development of complicated diverticulitis resulting in abscess surgery or fistula.
Collectively, these findings indicate that our patients do not necessarily need to avoid these foods. Instead, we can advise them to adopt an anti-inflammatory diet, such as the Mediterranean diet, which this recent study in women indicated had risk-reduction benefits. My own patients find these diets very easy to follow and quite practical.
Modifiable Risk Factors for Recurrence
The recurrence rate for diverticulitis is notably high. Within the first year after complete recovery, 8% of patients have an episode of recurrence, and approximately 20% within 10 years. The risk increases with subsequent episodes. After a second episode, it rises to 18% at 1 year and 50% at 10 years. After a third episode, the risk for recurrence is 40% at 3 years.
Therefore, it's important to identify for our patients anything they can prospectively and proactively do to prevent a recurrent episode. There are several commonsense risk factors our patients should avoid.
Smoking reduction or abstinence has proven benefits. Alcoholism, but not alcohol in and of itself, is associated with a higher risk. Chronic nonsteroidal anti-inflammatory drug (NSAID) use is a known risk factor. Guidelines recommend the avoidance of regular NSAID use, although aspirin should be continued when justified for cardiac indications.
Weight reduction, particularly among those with truncal obesity, seems to reduce the risk for diverticulitis. Vigorous physical activity also has an inverse, beneficial relationship for diverticulitis.
Identifying all these approaches is a good, simple way to help patients going forward.
Symptoms, Scans, and Supplementation
The guidelines are shifting around the rush to use antibiotics for episodes of recurrence. For uncomplicated diverticulitis, antibiotics don't seem to do better than not using antibiotics.
In general, we have shifted toward advising that patients adopt a clear liquid diet, avoid antibiotics, and inform us if they experience any alarm features, particularly fever or worsening pain.
Exceptions to the recommendations to avoid antibiotics are made for patients who are frail, have multiple comorbidities, are immunocompromised, or have laboratory findings of severe inflammation, including C-reactive protein > 140 mg/L or a white blood count > 15,000. In such patients, antibiotics are still indicated right away.
The extent of diverticulitis involvement on a CT scan would also be an indication for antibiotics. However, we don't want to rush to recommend a CT scan in all patients. This reflects our increasing awareness of the radiogenic risk of CT scans and abdominal CT scans, which I discussed in a recent video. CT scans are really overutilized, and we potentially need to take a step back in when we use them.
Vitamin D status is another important factor, which I touched on in a recent article. Low vitamin D levels are associated with a higher risk for diverticulitis. I routinely check the vitamin D levels in my patients and generally recommend vitamin D supplementation, given its very low risk and potential prophylactic value in patients with a history of diverticulitis.
Genetic Predisposition
There's a strong genetic predisposition for diverticulitis, which we often overlook in our discussions with patients. Over 30 genetic loci have been associated with diverticulosis, and at least four seem to be associated with diverticulitis.
This is key when considering patients with a family history of diverticulitis, including their siblings. In monozygotic twins, the risk is higher than in dizygotic twins, accounting for about 50% of the recurrence risk for diverticulitis. We need to be proactive when asking about family history in order to identify patients who are at greater risk for disease development or recurrence.
Lastly, I always tell my patients that intermittent, lingering symptoms, such as cramping, are quite common. About 45% of patients experience intermittent symptoms after recovery, which is mostly attributable to visceral hypersensitivity. There may also be a microbiome-related explanation for motility-related muscular changes related to diverticular disease.
We can assure patients that they don't need to be alarmed by such symptoms, nor must they seek out immediate help from their healthcare provider. These symptoms are different from the acute and persistent worsening pain typified for diverticulitis. Instead, we can consider treating them with antispasmodics or low-dose antidepressants to manage their symptoms.
I hope this overview gives you practical, evidence-based tools for discussing the management of diverticular disease with your patients. These conversations can be a lot more meaningful when supported by the latest data, allowing us all to do a better job.
I'm Dr David Johnson. Thanks for listening, and I look forward to chatting with you again soon.
