In patients with cured or controlled acromegaly prevalence of colonic diverticula is double that seen in controls (37% versus 19%), according to a Dutch research group. This novel finding “adds diverticular disease to the currently recognized, irreversible effects of acromegaly,” write the researchers.

Even after acromegaly is cured or biochemically controlled, patients experience “persistent comorbidities, such as arthropathy and cardiac valvular disease,” explains researcher Nienke Biermasz (Leiden University Medical Center, the Netherlands). These adverse effects are attributed to changes in the composition of the extracellular matrix in the heart and joints, which led the researchers to hypothesize that similar changes might also affect other areas, such as the colonic wall.

Accordingly, the researchers conducted a case–control study to compare the colonoscopy findings in 321 patients: 107 patients with cured or controlled acromegaly and 214 controls matched for age and sex. All participants were undergoing routine colonoscopy to screen for colonic polyps. Such polyps frequently occur in patients with acromegaly, whereas the controls had other indications for polyp screening (such as rectal blood loss or aspecific abdominal complaints).

The duration and severity of active disease was also associated with the prevalence of colonic diverticula: patients with colonic diverticula had longer disease duration than those without colonic diverticula. The researchers attributed this finding to the duration of a patient's exposure to raised levels of growth hormone and insulin-like growth factor 1, which might be related to an increased propensity to develop diverticula. The researchers are planning several studies to assess “the long-term effects of transient elevations in growth hormone levels on bone, cartilage and collagen”.