Although mortality rates associated with inflammatory bowel disease (IBD) have declined substantially over recent years, patients diagnosed with IBD as adults still have a higher risk of death than the general population, a study has found.
The study, “Mortality in adult-onset and elderly-onset IBD: a nationwide register-based cohort study 1964–2014,” was published in the journal Gut.
IBD is made up a group of autoimmune disorders, including Crohn’s disease (CD), ulcerative colitis (UC), and IBD-unclassified (IBD-U), that cause inflammation of the gastrointestinal (GI) tract. As a result, patients experience bouts of abdominal pain and diarrhea, often accompanied by weight loss and rectal bleeding, which can pose a significant burden on their overall quality of life.
Although IBD has been linked to a higher risk of death, few studies have assessed the mortality risk among patients diagnosed with different forms of the disease.
“Indeed, and somewhat disturbingly in light of the changes in the treatment paradigm for IBD during the last 20 years, there are only little data on mortality in patients diagnosed with either UC or CD after 2000. Furthermore, there are no studies on mortality in patients with IBD-U and only inconsistent data regarding cardiovascular and several other causes of death in IBD,” the investigators wrote.
In this study, the group of researchers from the Karolinska Institutet in Sweden set out to examine the mortality rates over the past 50 years specifically associated with IBD and with all causes in a group of patients who had developed IBD as adults.
To do this, they used the Swedish National Patient Register to gather data from IBD patients who had developed the disease in adulthood between 1964 and 2014. They then used the Swedish civic registration number system to cross-reference patients’ clinical data with their cause of death.
The nationwide study included data from 82,718 adult-onset IBD patients — 50,684 with UC, 25,582 with CD, and 6,452 with IBD-U — together with 801,180 individuals from the general population used as controls. The study also analyzed data from a subgroup of 17,873 IBD patients who had developed the disease after the age of 60 (elder-onset IBD), an age group for which detailed information on mortality rate is very limited.
Results showed that in general IBD patients were approximately 1.5 times more likely to die during the follow-up period of the study, compared with individuals from the general population, which corresponds to one extra death per 263 patients each year. This increased chance of mortality was identical between patients with adult- and elder-onset IBD.
In addition, the researchers found this higher mortality risk was also similar in patients from all IBD subtypes, ranging from 1.4 to 1.6 times higher than controls.
Moreover, they showed that IBD patients were also at a higher risk of dying from other common causes of death, including heart disease (1.3 times higher), cancer (1.4 times higher), and gastrointestinal disease (5.2 times higher) than individuals from the general population.
When the researchers analyzed mortality time trends, they found that since 1964, mortality rates had decreased significantly among both IBD patients and individuals from the general population. In the case of IBD patients, this reduction in mortality rates was stronger during the first five years of follow-up.
“This is very good news. Treatments for IBD, both medical and surgical, have improved greatly over the past 20 years due not least to the introduction of immunomodulating and biological drugs. It is one of our future goals as researchers to identify treatments that have a great protective effect,” Ola Olén, MD, PhD, a consultant and researcher in the department of medicine at the Karolinska Institutet and lead author of the study, said in a press release.
Despite the overall decrease in mortality rates, the group of IBD patients who had been diagnosed between 2002 and 2014 still had a shorter lifespan (2.3 years less on average) than matched individuals from the general Swedish population.
“Patients with IBD remain at an almost 50% increased risk of death despite modern treatment. Given the rise in IBD prevalence globally (in Sweden, 1 in 160 individuals have IBD), we need to optimize treatment but potentially also screening for cancer and preventive measures against cardiovascular disease to facilitate an efficient and cost-effective care of IBD,” the researchers wrote.