One of the first things people with Crohn’s and UC learn is: avoid stress. Stress makes inflammatory bowel disease worse. I can’t count how many times I have heard this from physicians, nurses, and other patients.
The problem is, it isn’t true for many people (for example: me). And, in fact, the scientific evidence is mixed, maybe even weak. Some studies show that stress makes IBD worse. Some studies show it doesn’t. The consensus among doctors and scientists is that there is a link, but nobody knows exactly how stress and symptoms are connected.
A new article in the American Journal of Gastroenterology sheds some light on that question, and suggests stress has no effect on inflammatory bowel disease — or at least not on the ‘inflammatory’ part.
Whether stress makes IBD worse, it turns out, depends on the key distinction between ‘symptoms’ and ‘disease’.
Some context: the first studies to look at the link between stress and IBD were published in 1991 — I’ll call them Duffy, et al and McKnight, et al, respectively (I’ll put full citations below). McKnight looked at ‘minor daily stressors’ for 10 people with Crohn’s for 28 days — but that’s not enough people or enough time to count as good evidence. Duffy looked at more people for longer — 124 UC and CD patients for up to seven months — but their results showed that IBD symptoms coincided with stressful events, but did not follow stressful events.
More recent studies find no link between stress and IBD, such as Lerebours, et al in 2007 — with 241 patients, and Vidal, et al in 2006 — with 163 IBD patients — which concluded that “stressful life events do not trigger exacerbations in patients suffering from IBD”.
A 2008 meta-analysis of several studies found some evidence for a link between stress and IBD, but the authors admit: “the inconsistency of the evidence remains.” The review also looked at five randomized trials of stress reduction treatments, and found that only one showed a definite effect.
One of the problems with almost all of these studies is that they depend on patients self-reporting their symptoms. It’s not that patients are imagining those symptoms: the symptoms are real. But symptoms don’t necessarily correlate to the actual inflammatory processes of the disease.
What makes this latest study fascinating is that it looks at both self-reported symptoms and inflammation. The authors had patients complete surveys, but also tested their fecal calprotectin. “FCAL” is a relatively new test that detects inflammation in stool samples by the presence of broken-down white blood cells.
The authors found that stress had a strong effect on symptoms: “the factor most consistently associated with active disease symptoms in both CD and UC was having a high level of perceived stress.”
But… they also found that “stress was not concurrently associated with inflammation in either CD or UC”. Stress did not make inflammatory bowel disease worse, in the sense that it did not worsen the inflammation, i.e. the disease itself.
So what’s happening? Why does stress seem to make IBD worse, without affecting actual inflammation? The authors discuss a few possibilities:
- People with IBD might pay more attention to their symptoms in times of stress, making them more likely to report those symptoms than people with lower stress.
- Stress might make self-care more difficult for people with IBD, making them sleep less, eat worse, forget meds, and so on – thus making symptoms worse.
- Stress may affect how neurons in the brain perceive pain and how neurons in the gut regulate our bowels, making pain more painful and guts more active.
- Stress may affect immune system activity in ways that are not yet understood, thus making symptoms worse.
The authors point out that the “relationship between perceived stress and disease is further complicated because experiencing unpleasant symptoms can in itself be a stressor” — meaning there’s a chicken-egg problem, in that it’s not always clear whether the symptoms or the stress came first.
This is a very strong study, but it doesn’t prove there is no relationship between stress and inflammation. In a larger context, it does help us unpack the idea that ‘stress makes IBD worse’. In a strictly technical sense, that was not true for the patients in this study, but the fact that it did worsen their self-reported symptoms cannot be dismissed. More research is needed.
But wait… there’s more!
A surprising result from the study was that self-reported symptoms were also not strongly linked to inflammation for people not experiencing stress — especially in Crohn’s patients. This has two potential consequences: first, that symptoms are not reliable evidence of active inflammation. Second, that treating inflammation might not solve the symptoms.
IBD patients often hear the mantra: “Treat the disease, not the symptoms”. The evidence in this study suggests this is wrong — at least for some patients, some of the time. The authors:
Our findings suggest that relying solely on the presence or the severity of symptoms to guide anti-inflammatory-based therapy may be ill-advised, and that assessing the presence of inflammation is recommended to determine the need for initiating or adjusting anti-inflammatory therapy or confirming therapeutic response.
So if you have symptoms of IBD, it’s a good idea to get tested for active inflammation. If you do not have active inflammation, your doctor should still take your symptoms seriously — and treat them.
And if stress makes your symptoms worse, you should take that seriously — but also take comfort that it probably isn’t making the disease any worse.
*The main study discussed here is Targownik, LE; et al. “The Relationship Among Perceived Stress, Symptoms, And Inflammation In Persons With Inflammatory Bowel Disease”. American Journal of Gastroenterology 2014 110:1001-1012; doi: 10.1038/ajg.2015.147 . A copy of the study was provided by Dr. Targownik, for which I am grateful.
Duffy, LC; et al. “Lag Time Between Stress Events And Risk Of Recurrent Episodes of Inflammatory Bowel Disease”. Epidemiology March 1991. Available online as PDF
McKnight, GT; et al. “The Relation Between Daily Stress And Crohn’s Disease”. Journal of Behavioral Medicine February 1991 14:1, pp. 87-96. Abstract online.
Lerebours, E; et al. “Stressful Life Events As A Risk Factor For Inflammatory Bowel Disease Onset: A Population-Based Case-Control Study”. American Journal of Gastroenterology 2007 102, pp. 122-131. doi:10.1111/j.1572-0241.2006.00931.x Abstract online.
Vidal, A; et al. “Life Events And Inflammatory Bowel Disease Relapse: A Prospective Study of Patients Enrolled In Remission”. American Journal of Gastroenterology 2006 101, pp. 775-781. Abstract online.
Maunder, RG; and Levenstein, S. “The Role Of Stress In The Development And Clinical Course Of Inflammatory Bowel Disease: Epidemiological Evidence”. Current Molecular Medicine 2008 8, p. 247-252. Available online as PDF.
If the links are broken, you should be able to find the abstracts by googling -IBD stress [author name, date]-.
Photo “stress” by Flickr User bottled_void used by CC license.