Crohn's Disease Activity Index

The Crohn's Disease Activity Index (CDAI) is a tool used to assess the severity and symptoms of Crohn's disease. The index uses eight factors, each given a different weight, to determine remission or response to treatments.
Because Crohn's disease is an inflammatory bowel disease with symptoms and severity that vary from person to person, and each person can have a wide range of severity with his symptoms, doctors don't have one specific treatment modality that fits all, or even most, patients.
The CDAI helps physicians determine when a treatment is working for a patient.

History

• The National Cooperative Crohn's Disease Study group developed the CDAI in 1976 in order to have a single index that physicians could use to determine the degree of illness in patients with Crohn's Disease. The index was created by looking at common symptoms and problems faced by many Crohn's disease sufferers.

Function

• The function of the CDAI is to get a snapshot of the severity of symptoms of a patient, then to use that number as a baseline when determining how well treatments work for that patient. The CDAI will be used periodically to see if symptoms have improved, worsened or stayed the same.

Factors Considered

• There are eight factors taken into account for the CDAI, each given a different weight:
  Percentage deviation from standard weight (x1)
  Number of liquid stools each day, for seven days (x2)
  Abdominal pain each day for seven days (x5)
  Deviation of hematocrit levels (number and size of red blood corpuscles, which is normally 47% for men and 42% for women) (x6)
  General well-being each day for seven days (x7)
  Presence of abdominal mass (x10)
  Presence of complications (x20)
  Taking Lomotil or opiates for diarrhea (x30)

Benefits

• Doctors can determine a quantifiable effect of treatment based on the CDAI, which is better than considering only subjective factors given by patients on how they feel. The patient's feelings and input are taken by the CDAI and given consideration alongside more concrete measurables. Any treatment that results in a drop of 70 points or more in a patient's CDAI score is considered effective.

Considerations

• A patient's CDAI score will fluctuate and needs to be monitored consistently. Any treatment can lose effectiveness, and a patient might go into or come out of remission, so going back to the CDAI results will allow health care professionals to monitor when a treatment is losing effectiveness.