Mortality from IBD

A large Danish cohort provides useful information on the mortality effects of having inflammatory bowel disease (IBD) and how this has changed over the last three decades (Clin Gastroenterol Hepatol 2013; 11: 43-48).

Using a national cohort of all individuals living in Denmark between 1982-2010 (on average 5.3 million), the authors studied 36,080 patients with ulcerative colitis (UC) and 15,361 with Crohn’s disease (CD) in comparison to data from 2,858,096 matched controls (50 controls from each IBD patient) from the general population.  For UC, the median age was 45.2 years and for CD 36.3 years.

Findings:

  • With UC, the first year of diagnosis carried a higher risk of dying (HR 2.43) then rapidly declined to around HR 1.1 after 2 years.  Overall, long-term mortality was increased 10% among UC patients.  Mortality from UC decreased from 1982 to 2010 due to decreased mortalities from gastrointestinal disorders, including colorectal cancer.
  • Mortality was higher among patients diagnosed at younger ages.  Patients diagnosed with UC in childhood or adolescence had a 2.15-fold higher relative mortality than patients diagnosed with UC at 60-79 years.
  • Cause-Specific Mortality: during the first year after UC diagnosis, the HR ratio was increased markedly for gastrointestinal disease (HR 13.3) and infection (HR 9.17).  These areas were most prominent at 10+ years, but the HR ratios had decreased to 1.95 and 1.64 respectively at that time.
  • For CD, mortality was markedly increased in the first year with HR 3.69 and declined to HR 1.53 during years 2-4; HR was 1.49 at 10+ years following diagnosis.  Overall, long-term mortality was increased 50% among CD patients.  Unlike UC, no improvement in mortality rate occurred during the study.
  • Cause-Specific Mortality: during the first year after CD diagnosis, the HR ratio was increased markedly for gastrointestinal disease (HR 23.02) and infection (HR 10.19). These areas were most prominent at 10+ years, but the HR ratios had decreased to 3.67 and 2.70 respectively at that time.  Infections were not increased in the most recent decade, indicating that thiopurines and biologics have not increased the overall risk of fatal infections.
  • While the relative risk of cardiovascular disease was only slightly increased (HR 1.11 for both CD and UC), this is important given the overall frequency of cardiovascular disease in the population.  Presumably, systemic inflammation contributes to the formation of atherosclerosis.
  • Suicide was also increased, especially in the first year after diagnosis (HR 2.05 for UC and HR 1.37 for CD)

Strengths of study: since Denmark has free access to health care and all citizens have a unique 10-digit personal identification, this enables capture of virtually all patients with IBD.  Previous studies have validated the database to be accurate and that the IBD diagnoses have been validated.

Related blog entries:

Where is the Journal Editor?

A recent article is titled “Determination of Bone Age in Pediatric Patients with Crohn’s Disease Should Become Part of Routine Care” (Inflamm Bowel Dis 2013; 19: 61-65). (Thanks to Ben Gold for suggesting this reference.)

Does the study merit the authors’ conclusion that ‘determination of bone age (BA) should become the standard of care in pediatric Crohn’s disease (CD) patients, allowing clinically meaningful interpretation of growth…leading to improved treatment recommendations?’

No.  This small study (n=49, 84% Caucasian) simply showed that a lot of pediatric CD patients have a delayed bone age.  This is not a novel finding.

Specifically, the mean BA Z score was -1.40 ± 1.5 in this population and 41% had a BA Z score of < -2.0.  This cross-sectional study was conducted between 2007-2009.  Patients were consecutively approached for enrollment during this time period.

Clinical factors associated with delayed bone age included Caucasian race, Tanner stage 1-3, history of steroid exposure, colonic disease location, azathioprine/6-mercaptopurine usage, and female sex.  Interestingly, these variables are not entirely consistent with prior studies in which male sex was associated with delayed bone age.

The reason why the conclusion is a far-reach is that there is no data in the study showing how bone age influences any clinical decision-making in these patients.  There is no information on cost-effectiveness of their proposed “standard of care.”  There is no longitudinal data to suggest that the delayed BA or the recognition of a delayed BA  resulted in a different outcome.

My conclusion:

Many pediatric patients with CD have delayed BA and some may benefit from a BA determination.  I think extrapolating a much broader conclusion from this study is not warranted.

T-cell therapy for Crohn’s disease

Data from the Crohn’s and Treg Cells Study (CATS1) are very preliminary but indicate that administration of antigen-specific T-regulatory cells (Tregs) to refractory Crohn’s disease (CD) patients could be effective (Gastroenterol 2012; 143: 1207-17).  Tregs are specialized subpopulations of T-cells.

In this study, the investigators, performed a 12-week open-label multicenter single injections study of 20 patients with refractory CD.  After withdrawing blood from patients, mononuclear cells were isolated and cultured.  Subsequently, T cells were cloned.  A specific subset with high IL-10/IL-13 production and low IL-4 production were selected.

Key findings:

  • 8 of 20 (40%) patients had a CDAI reponse at 5 and 8 weeks.  This was associated with a reduction in serum CRP and a trend of decreasing fecal calprotectin.
  • Remission was noted in 3 patients at week 5 and in 2 patients at week 8.
  • Overall, regardless of dose used, the safety profile was “in line” with severe active refractory CD.  Gastrointestinal adverse events were common.  7 patients had CD flares. One patient died due to suicide.

To understand this study more fully, an accompanying editorial is in the same issue (pages 1135-38).  A more complete discussion of the function of Treg cells is given, included their physiologic role of patrolling the gut lamina propia for antigens ‘derived from food and commensal flora.’  Circulating Treg cells may be deficient in IBD patients and thus contribute to the pathogenesis.

While injecting Treg cells may become a useful therapy, other ways of boosting Treg cells may be enhanced as an alternative.  Currently, granulocyte colony-stimulating factor (GCSF), anti-TNFα agents, and IL-2 all have the potential to enhance Treg cell function.  This supports the editorial’s conclusion that ‘Treg cells are rapidly moving from the bench to the bedside.’

Given the experimentation with stem cell therapy and bone marrow transplantation for CD, Treg cells show promise of a much more targeted effect on the immune system.

Additional references:

  • -Blood 2010; 116:6123-32.  Autologus stem cell transplantation in patients with refractory CD.
  • -Gut 2008; 57: 211-17.  Autologus stem cell transplantation for refractory CD.
  • -Gut 2010; 59: 1662-69.  Mesenchymal stromal cell treatment for luminal Crohn’s.

Predictors of colectomy in pediatric UC

A recent review of children in the Pediatric Inflammatory Bowel Disease Consortium (PediIBDC) examined risk factors for proctocolectomy in children with Ulcerative Colitis (UC) (JPGN 2012; 55: 534-40).  Two of the investigators (Stanley Cohen and Ben Gold) are colleagues of mine at GI Care for Kids.

In total, 406 children with UC were reviewed.  The average age at diagnosis was 10.6 years.  The average followup was 6.8 years.  57 (14%) underwent surgery with a median time to surgery of 3.8 years.  Overall risk factors for colectomy included the following:

  • Presenting with weight loss, HR 2.55
  • Presenting with hypoalbuminemia (<3.5 g/dL), HR 6.05
  • First-degree relative with UC, HR 1.81
  • Treatment with cyclosporine, HR 6.11
  • Treatment with tacrolimus, HR 3.66

While this data expands on the knowledge of these factors in children, the findings are not unexpected.  Low albumin levels and poor nutritional status have been identified in other studies as risk factors for UC relapse and for colectomy.

With regard to first-degree relatives, the findings imply that children with a first-degree relative are more likely to have a more severe form of UC.

The use of calcineurin inhibitors, cyclosporine and tacrolimus, are given only in the presence of severe disease.  Thus, while use of these agents is associated with an increased risk of colectomy, it is unlikely that this is a causal relationship.  Interestingly, the use of infliximab was not identified as a risk factor.  However, this retrospective study examined patients between 1999-2003.  Since this timeframe, there has been increased use of infliximab for refractory UC.

Going forward, it is likely that contemporary studies would incorporate PUCAI (pediatric UC activity index) measurements and would have the ability to enroll far greater numbers of patients from database consortiums.

Related blog posts:

Predicting long-term response with calprotectin levels

This blog has been a fan of calprotectin levels (see related posts below) as both a screening test for inflammatory bowel disease and as a marker of disease activity.  Now more data is available indicating that calprotectin levels, much like endoscopic mucosal healing, after induction therapy correlates with long-term response (Inflamm Bowel Dis 2012; 18: 2011-17).

This retrospective study (2005-2010) examined 60 patients with IBD with elevated baseline calprotectin levels.  34 patients had Crohn’s disease (CD) and 26 had ulcerative colitis (UC).  42 patients received infliximab therapy and 18 patients received adalimumab.  After induction therapy, therapy was discontinued in primary non responders or continued as scheduled maintenance therapy for at least one year if not relapsing.

The average age at induction for CD patients was 30 and the corresponding age at diagnosis was 21.  For UC patients, the average age at induction was 29 and the corresponding age at diagnosis was 26.

Median calprotectin level at baseline was 810 μg/g (n=60).  After induction, the median value dropped to 97 μg/g (n=60) and at 1 year the value dropped to 27 μg/g (n=25).  The calprotectin level normalized in 31 patients after induction.  At 12 months, the sustained remission was present in 84% (26/31).  In contrast, only 38% (11/29) who had elevated levels after induction were in remission at 12 months.

Related blog entries:

More frequent pediatric IBD

Using a national cohort of prospective and retrospective data on pediatric inflammatory bowel diagnosis, (PIBD) a recent report indicates a rising incidence of PIBD in Scotland (Inflamm Bowel Dis 2012; 18: 999-1005).

Key findings:

  • Between 2003-2008, 436 patients were diagnosed with PIBD; this equates to 7.82/100,000; Crohn’s was 4.75 and UC 2.06 per 100,000 respectively
  • Between 1990-1995, 260 patients were diagnosed with PIBD; this equates to 4.45/100,000; Crohn’s was 2.86 and UC 1.59 per 100,000 respectively
  • Mean age of diagnosis in more recent cohort was younger: 12.7 years compared with 11.9 years

Currently, a data-base coordinated in a single center along with collaboration with regional networks enables the capture of all new IBD diagnosis (since 1999).  Prior cohort was determined by “exhaustive examination” of previous IBD records.

Running out of options

A series of articles on natalizumab were published which give practical advice for this drug which clinicians often turn to when ‘running out of options’ (Gastroenterol Hepatol 2012; 8: 4-17).

Slides from these articles should be available soon (not online on 1/2/13):

http://www.clinicaladvances.com/index.php/our_publications/gastro_hep-issue/gh_november_2012/

According to an algorithm on page 7, in patients with moderate-severe Crohn’s disease who have failed conventional therapies and anti-TNF drugs (or unable to tolerate), the next step is to obtain anti-JCV (John Cunningham Virus) antibody status.  Patients who test negative are ‘Okay to treat with natalizumab’ due to very low risk of progressive multifocal leukoencephalopathy (PML).  Repeated testing at least once a year is then recommended.

For patients who test positive for anti-JCV at any time point, natalizumab can be considered if no other treatment options are available, but the risk of PML is much greater. Previous blog entries (below) have discussed this in greater detail and have provided additional references:

Another article published the experience in 36 Mayo clinic patients between April 2008-September 2010 (Inflamm Bowel Dis 2012; 18: 2203-08).  Consecutive patients who received natalizumab were prospectively followed.  Of the 36 treated with natalizumab, 30 agreed to participate in the study.  23 patients had failed two anti-TNF agents and 7 had failed one anti-TNF agent.  Median age was 35 years.

Results:

  • 14 (46%) had a complete clinical response, 12 had a partial response, and four had no response.  Cumulative probability of a complete response within 1 year was 56%.
  • Time to response: 10% after 1st dose, 50% of patients had complete response after 4th dose
  • Adverse events were common –though this rarely caused drug cessation. Common events included headache and infections (listed in Table 4 of article).  Some infections prompted holding natalizumab for up to 8 weeks.
  • 11 stopped natalizumab due to lack of improvement.

Quality improvement and better outcomes in Pediatric Inflammatory Bowel Disease

More information on outcomes and quality improvement (QI) efforts are available from Cincinnati Children’s Hospital (JPGN 2012; 55: 679-88).  The QI efforts at Cincinnati are part of a broader effort in QI in pediatric IBD that has been discussed on a previous post (see below).

Our group has rejoined Improve Care Now (ICN) and I look forward to gaining more first hand experience.  Some of the ICN target goals:

  • 80% remission rate among each center and sustained remission rate of 45%
  • 76% steroid-free remission
  • 90% checking TPMT if using thiopurine
  • 95% checking PPD/chest xray if using biologic therapy
  • 95% using accepted methotrexate dosing

As I look at these goals, I wonder whether the remission rate is feasible and about the variation in different centers. For example, among the groups with >75% enrollment of their patients, one center reports a 89% remission rate and another center 64% remission rate.  Given the limited number of therapeutic agents, how could there be such a difference?  Some explanations could include variation in the use of more potent biologic agents as well as capturing/assuring followup of more patients who are doing well.

Given this backdrop, I looked at this most recent publication to learn how their QI practices could translate into better care for my patients.

In this retrospective chart review study of 505 patients, who were followed from 2007-2010 at the IBD center, the remission rate increased from 59% to 76%.  The data were captured prospectively.  This corresponded to improved patient global assessment (>7) from 69% to 80%.  Repeated steroid use dropped from 17% to 10%.  Vitamin D (25-OH D) improved and this also correlated with quiescent disease.

Remission rates were defined by a pediatric Crohn clinical disease index, the sPCDAI, or PUCAI for Ulcerative colitis.

Key observations:

  • There was a trend towards increased use of anti-TNFα therapy (along with decreased use of 6-mercaptopurine) during the study period, but this did not reach statistical significance. No statistical difference was identified in the use of any major IBD medication class.
  • Despite target goals, the only drug class with a statistically significant change in dosing was 5-ASA (from 42 mg/kg to 50 mg/kg).
  • Fecal calprotectin monitoring increased.  The QI team recommended that IBD patients with ‘inactive’ disease have a fecal calprotectin measured every 6 months.  Those with elevated values had therapeutic drug monitoring implemented.  “Fecal calprotectin >400 μg/g is associated with a higher chance of relapse in a pediatric cohort.”
  • Starting in 2009, increased vitamin D monitoring was implemented (every 6 months).  In patients with a serum 25-OHD level < 30 ng/mL, treatment with 50,000 units weekly (for 6-8 weeks) was recommended (8000 units if weight <20 kg).  Once serum 25-OHD was >30 ng/mL, patients were maintained on monthly dosing.
  • Preclinic planning also increased and corresponded to improved remission rates which were 67% in 2009 and 76% in 2010.
  • The authors conclude: “Our results show that significant improvement in patient outcomes were achieved following QI efforts that did not rely on new medications or therapies, rather through initiating novel care processes and standardization of care.”

I think this conclusion is misleading.  First of all, as the authors point out, they did change their therapeutic approach.  They started vitamin D in more patients, used anti-TNFα therapy in more patients, and increased dosing of 5-ASA agents.  Other gains in remission rate could have been related to improved followup of patients who were doing well.

Despite my skepticism about the conclusion, I think the overall achievements are laudable.  Decreasing variation of care and assuring that all patients receive the best care possible with our diagnostic tests and current therapies is certainly worthwhile.  When patient care is studied carefully, this makes sure that “standard” practice like checking TPMT status before thiopurine use, checking PPDs before anti-TNFα therapy, and using optimal drug dosing occur in virtually all patients.

Developing a checklist for each patient can help assure that best practices occur.  For those with electronic medical records, this may mean putting in more “hard stops.”  A hard stop means the physician cannot sign out of a chart without paying attention to a specific detail.  For example, if a physician orders methotrexate, a “hard stop” could come up if the dosing was not in the typical target range.

Useful link:

Link for disease classification (quiescent, mild, moderate, severe):

http://links.lww.com/MPG/A129

Related blog entries:

Best strategy for dose escalation of infliximab

At least 50% of patients with long-term infliximab therapy require dose escalation.  However, dose escalation can mean doubling the dose or shortening the infusion interval.  So which strategy is best?  A recent article provides some insight into this question (Inflamm Bowel Dis 2012; 18: 2026-33).

In this multicenter retrospective study of 168 Crohn’s disease (CD) patients, the outcome of patients who had dose-doubling (n=112) to 10 mg/kg/dose/8 weeks was compared with patients whose infusion intervals were halved to 5 mg/kg/dose/4 weeks (n=56).  The entire cohort had a mean age of 25 years and a mean disease duration of 12 years.  39% had a history of previous intestinal surgery.  Concurrent use of thiopurines was noted in 68% and concurrent use of methotrexate in 4%.

Sustained response at 1 year to dose-doubling strategy was 50% compared with 39% in the interval-halving group.  Favorable factors included nonsmoking status, normal C-reactive protein, and CD diagnosis between 16-40 years of age.

It is noted that a subsequent dose escalation was experienced by 28 of the 87 patients who had loss of response after first dose escalation.  Regained response occurred in 9 (32%) of this cohort.

The authors indicate that increasing the dose to 10 mg/kg/8 weeks is likely preferable due to convenience and cost.  At the same time, it is apparent that shortening the infusion interval is not likely to be more effective than dose doubling.

Related blog entries:

Does bone density improve with IBD therapy?

Long term followup is needed to determine the significance of low bone mineral density (BMD) in children and adolescence with IBD; data with 2 year followup is available (JPGN 2012; 55: 511-18).

In this study from Sweden, 144 patients with IBD were enrolled and 126 were available at 2-year followup (2003-2005).  Among the 144 patients, there were 93 males and 83 with UC. Low BMD was noted in children with both UC and CD for the lumbar spine at baseline and no improvement was noted at 2 years.  Only boys had lower BMD z scores for the lumbar spine (LS) (-1.1); girls had normal LS z scores (0).

While the investigators could not demonstrate catch up in bone mineral density, they note that gains in BMD may accrue beyond late adolescence into early adulthood; this takes place after completion of linear growth.  In the subgroup of subjects in early adulthood, there was improvement in BMD:

  • For boys: from -1.7 at baseline (age 17.9) to -0.5 at followup (age 20.0)
  • For girls: from -0.4 at baseline (age 17.1) to 0.4 at followup (age 19.2)

With greater use of biologic therapy, these data are likely to change.  Among medical treatments, only biologic therapies have been shown to improve bone formation and improve catchup growth.

Related blog entry:

Additional references:

  • -JPGN 2011;53: 361. Similar prevalence of low Vitamin D as general population –58% with less than 32.
  • -JPGN 2011; 53: 11. Guidelines for low bone mineral density in IBD.
  • -JPGN 2009; 48: 538. Need to adjust bone density for bone age.
  • -Gastroenterol 2009; 136: 123. Longitudinal bone health study. Steroids did NOT adversely affect bones. n=78.
  • -Clin Gastro & Hep 2008; 6: 1378. IFX improves biomarkers of bone formation.
  • -J Pediatr 2008; 153: 454, 484. Use of biomarkers of bone turnover in Crohn dz; even when controlling for other factors like delayed bone age, delayed puberty, etc, still evidence of decrease bone formation and increased resorption.
  • -JPGN 2007; 45: 538. Ca/Vit D supplements -no change in BMD in IBD patients over 12 months.
  • -Clin Gastro & Hep 2007; 5: 721. DXA may not predict risk well.
  • -IBD 2007; 4: 416. Inflammation, not steroids, is key factor in bone mineral density.
  • -IBD 2006; 13: 42. Natural hx of bone mineral density in IBD; steroid dose did not correlate with BMD. Children did not have “catch up” bone density.
  • -JPGN 2006; 43: 597. Crohn’s patients had similar rate of fractures as siblings w/o IBD.
  • -Clin Gastro & Hep 2006; 4: 152. Osteoporosis in IBD.
  • -IBD 2006; 12: 797. Review of bone mineral density with IBD
  • -Clin Gastro & Hepatol 2005; 3: 113-121, 122-132 & editorial 110. In 1st article, budesonide better for bones than other steroids. In 2nd article, unable to show benefit of addition of etidronate to Ca++/Vit D.
  • -NEJM 2002; 351: 868. Intermittent steroids in nephrotic syndrome did NOT change bone mineral density.
  • -Gastro 2001; 121: 1485-88. Tanning bed Rx of vitamin D deficiency.
  • -Gastro 2000; 119: 639-46. Alendronate increases BMD in pts c Crohn’s
  • -NEJM 1998; 339: 292-9/ J Bone Miner Res 2000; 15: 1006-13. Bisphosphonates effective in steroid-induced bone disease