Charlson Comorbidity Index

The Charlson Comorbidity Index is a method of classifying prognostic comorbidity in longitudinal studies.

Some Comorbid Diagnosis have points associated with them that contribute to an overall comorbidity score. This score reflects the cumulative increased likelihood of one year mortality.

Structure

Contains 19 primary medical conditions of comorbidity some of which contain subcategories of diseases related to the primary category. For a list of all diagnosis applicable that we use go to: Charlson Comorbid Diagnosis (or Charlson Comorbid coding (pre ICD10)#Comorbid_List as former may not include all sub-diagnoses).

ICD10

See

• Charlson Comorbidities in ICD10 codes
• Charlson Comorbidity scoring in ICD10 codes

Collection Start Date

September 14, 1998

Data Use

• ALERT Scale score for Medicine
• the dxs involved are also used in Overstay
• Some items are use for APACHE II score for Critical Care. For a specific list of chronic condition applicable to APACHE II scoring see: Chronic Health APACHE
• Template:Discussion is this used in Reporting? If so, which? Ttenbergen 01:25, 2017 September 23 (CDT)

Background

The Charlson Index was developed in 1987 based on 1-year mortality data from internal medicine patients admitted to a single New York Hospital and was initially validated within a cohort of breast cancer patients. The index encompasses 19 medical conditions weighted 1–6 with total scores ranging from 0–37. In the development phase of the index, mortality for each disease was converted to a relative risk of death within 12 months. A weight was then assigned to each condition based on the relative risk (RR); for example,

• RR <1.2 = weight 0,
• RR ≥ 1.2<1.5 = weight 1,
• RR ≥ 1.5<2.5 = weight 2,
• RR ≥ 2.5<3.5 = weight 3,
• and for 2 conditions (metastatic solid tumor and AIDS) = weight 6.

From the weighted conditions, a sum score can be tallied to yield the total comorbidity score.

Article and related publications

• "A new method of classifying prognostic comorbidity in longitudinal studies: development and validation" ME Charlson
  • PDF of article (also: A PDF of the complete original article can be found on- X:\CCMDB_ADMIN_DATABASE\Charlson_Comorbids\OriginalCharlsonArticlePDF)
  • image of Charlson article, page 2.

• Article: An electronic application for rapidly calculating Charlson comorbidity score. Article with link to a comorbid score calculator developed in MS Excel using a macro.
  • Copy of this calculator can be found: X:\CCMDB_ADMIN_DATABASE\Charlson_Comorbids\comorbid calculator

• "Coding algorithms for defining comorbidities in ICD-9-CM and ICD-10 administrative data" Hude Quon

• MCHP Resources:
  • SAS code to convert IC10 to Charlson
  • Deyo and Quon Charlson ranges

Legacy

See Category:Charlson Comorbid Diagnosis (pre ICD10) for how Charlson was calculated before ICD10.