A systematic review and meta-analysis of disease severity and risk of recurrence in young versus elderly patients with left-sided acute diverticulitis

Young patients are thought to have a more severe disease course and a higher rate of recurrent diverticulitis. However, these understandings are mainly based on studies with important limitations. This review aimed to clarify the true natural history of acute diverticulitis in young patients compared to elderly patients. PubMed and MEDLINE were searched for studies reporting outcomes on disease severity or recurrences in young and elderly patients with a computed tomography-proven diagnosis of acute diverticulitis. Twenty-seven studies were included. The proportion of complicated diverticulitis at presentation (21 studies) was not different for young patients (age cut-off 40–50 years) compared to elderly patients [risk ratio (RR) 1.19; 95% confidence interval 0.94–1.50]. The need for emergency surgery (11 studies) or percutaneous abscess drainage (two studies) yielded comparable results for both groups with a RR of 0.93 (95% confidence interval 0.70–1.24) and 1.65 (95% confidence interval 0.60–4.57), respectively. Crude data on recurrent diverticulitis rates (12 studies) demonstrated a significantly higher RR of 1.47 (95% confidence interval 1.20–1.80) for young patients. Notably, no association between age and recurrent diverticulitis was found in the studies that used survival analyses, taking length of follow-up per age group into account. In conclusion, young patients do not have a more severe course of acute diverticulitis. Published data on the risk of recurrent diverticulitis in young patients are conflicting, but those with the most robust design do not demonstrate an increased risk. Therefore, young patients should not be treated more aggressively nor have a lower threshold for elective surgery just because of their age.