Does Depression Increase the Risk for Inflammatory Bowel Disease?

Depression increases the risk for Crohn’s disease in women, according to a study published in the January issue of Clinical Gastroenterology and Hepatology. Psychological factors might therefore contribute to development of this disorder.

Anxiety, depression, and other psychological disorders are common in people with Crohn’s disease (CD) and ulcerative colitis (UC). But do depression and stress increase the risk for inflammatory bowel diseases in patients that never had them before?

Ashwin Ananthakrishnan et al. analyzed data from 152,461 women enrolled in the Nurses’ Health Studies I and II. Beginning in 1991−1992, the participants were given a questionnaire about depressive symptoms (the Mental Health Index-5) to estimate their level psychological distress—the participants also completed the questionnaire at later timepoints.

Ananthakrishnan et al. then used statistical analyses to determine whether depressive symptoms and psychological stress affected risk for CD or UC.

They found that depressive symptoms increased the risk for CD more than 2-fold. CD appeared to have a stronger association with recent depressive symptoms (within 4 years of diagnosis), but earlier depression and stress, even when the surveys were first given, also affected CD risk.

However, depressive symptoms were not associated with risk for UC. “I think it’s very interesting to identify environmental risk factors that potentially have a differential effect on Crohn’s disease and ulcerative colitis, because finding such risk factors improves our understanding of why these conditions develop”, said Ananthakrishnan in a video abstract that accompanies the article.

Video abstract

Ananthakrishnan et al. found that depressive symptoms  increased risk for CD similar to levels of other, previously reported factors, such as smoking, use of oral contraceptives, and non-steroidal anti-inflammatory drugs.

Studies of animal models have demonstrated the effect of stress on immune function and susceptibility to colitis, and human studies that have associated depression or stress with disease incidence and relapse.

“Our study shows that depression and stress can even predate a diagnosis of Crohn’s disease and ulcerative colitis—it would be very interesting to examine how these psycho-social factors affect the immune system and how the disease develops and behaves”, Ananthakrishnan said in the video abstract.

Depression has been associated with increased levels of C-reactive protein and tumor necrosis factor (TNF)–α, which mediate inflammation in patients with inflammatory bowel diseases. Acute experimental stress or stressful life events can affect numbers and activities of lymphocytes, as well as platelet function and activation.

Preliminary animal and human studies have shown that treating depression with antidepressants or coping mechanisms could reduce risk of inflammatory bowel disease relapse.

In an editorial that accompanies the article, Faten Aberra and James Lewis suggest that for individuals with a first-degree relative with inflammatory bowel disease, more aggressive screening for mood disorders and early intervention could prevent disease onset.

Read the article online.
Ananthakrishnan AN, Khalili H, Pan A, et al. Association between depressive symptoms and incidence of crohn’s disease and ulcerative colitis: results from the nurses’ health study. Clin Gastroenterol Hepatol 2013;11:57-62.

Read the accompanying editorial.
Aberra FN, Lewis JD. As in the chicken or the egg: stress or inflammatory bowel disease? Clin Gastroenterol Hepatol 2013;11:63-64.