Summary: Diagnosis of inflammatory bowel diseases like Crohn’s disease and ulcerative colitis during adulthood has been linked to a 50% higher mortality rate and shorter life expectancy in those over 50. The increased risk of death remained after the introduction of therapies aimed at treating the conditions but decreased over time.
Source: Karolinska Institute
While the onset of inflammatory bowel disease (ulcerative colitis or Crohn’s disease) in adulthood is tied to higher mortality, the actual number of deaths has been falling, a Swedish study from Karolinska Institutet published in the journal Gut reports. Now it is a case of ascertaining which of the newer treatments are the most efficacious, say the researchers.
Using the Swedish National Patient Register, the team identified patients who had developed inflammatory bowel disease (IBD), such as ulcerative colitis or Crohn’s disease, in adulthood between the years 1964 and 2014. Thanks to the Swedish civic registration number system, they were then able to cross-reference the disease data with the cause of death registry and study IBD-related mortality in over 80,000 patients – both in the entire patient population and in patients who had been diagnosed with IBD after the age of 60, a sub-group for which there has been a lack of detailed mortality data.
The results for this older group were little different from those for the entire patient sample. Patients who had developed IBD in adulthood or after the age of 60 were found to have a 50 per cent higher mortality than people without IBD, which corresponds to a shortened life expectancy of 2.3 years.
Cardiovascular disease and cancer
“If you monitor a group of adults and elderly without IBD in Sweden, 1 out of 83 will die within a year, while the corresponding figure for people diagnosed with IBD as adults or elderly is 1 in 63,” says corresponding author Ola Olén, consultant and researcher at the Department of Medicine, Karolinska Institutet (Solna).
The most common causes of death were cardiovascular disease and cancer, while death due to gastrointestinal disease accounted for the highest relative risk.
“Cardiovascular disease and cancer are the most common causes of death in the population as a whole, and here there is no difference between IBD patients and Swedes in general,” he continues. “But it seems as though the mortality of IBD patients is higher for a number of different diseases.”
The researchers also managed to identify sub-groups with particularly high mortality. While there were small differences between Crohn’s disease and ulcerative colitis, the mortality rate for patients with both IBD and primary sclerosing cholangitis (a chronic liver disease) was three times higher. It is therefore important that these patients are monitored especially carefully, they point out.
Treatments have improved greatly
At the same time, they were also able to show that IBD-related deaths have declined over time.
“This is very good news,” says Dr Olén. “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.”
Funding: The study was financed by the Swedish Society of Medicine, the Swedish Gastrointestinal Foundation, Karolinska Institutet’s Foundations and Funds, ALF, the Swedish Cancer Society, the Swedish Research Council and the Swedish Foundation for Strategic Research. Some of the authors have received grants and/or fees for other projects from pharmaceutical companies such as Janssen, Pfizer, Ferring and AstraZeneca.
About this neuroscience research article
Source: Karolinska Institute Media Contacts: Felicia Lindberg – Karolinska Institute Image Source: The image is in the public domain.
Mortality in adult-onset and elderly-onset IBD: a nationwide register-based cohort study 1964–2014
Objectives To examine all-cause and cause-specific mortality in adult-onset and elderly-onset IBD and to describe time trends in mortality over the past 50 years.
Design Swedish nationwide register-based cohort study 1964–2014, comparing mortality in 82 718 incident IBD cases (inpatient and non-primary outpatient care) with 10 times as many matched general population reference individuals (n=801 180) using multivariable Cox regression to estimate HRs. Among patients with IBD, the number of participants with elderly-onset (≥60 years) IBD was 17 873.
Results During 984 330 person-years of follow-up, 15 698/82 718 (19%) of all patients with IBD died (15.9/1000 person-years) compared with 121 095/801 180 (15.1%) of reference individuals, corresponding to an HR of 1.5 for IBD (95% CI=1.5 to 1.5 (HR=1.5; 95% CI=1.5 to 1.5 in elderly-onset IBD)) or one extra death each year per 263 patients. Mortality was increased specifically for UC (HR=1.4; 95% CI=1.4 to 1.5), Crohn’s disease (HR=1.6; 95% CI=1.6 to 1.7) and IBD-unclasssified (HR=1.6; 95% CI=1.5 to 1.8). IBD was linked to increased rates of multiple causes of death, including cardiovascular disease (HR=1.3; 1.3 to 1.3), malignancy (HR=1.4; 1.4 to 1.5) and digestive disease (HR=5.2; 95% CI=4.9 to 5.5). Relative mortality during the first 5 years of follow-up decreased significantly over time. Incident cases of 2002–2014 had 2.3 years shorter mean estimated life span than matched comparators.
Conclusions Adult-onset and elderly-onset patients with UC, Crohn’s disease and IBD-unclassified were all at increased risk of death. The increased mortality remained also after the introduction of biological therapies but has decreased over time.