Development and validation of new multimorbidity-weighted index for ICD-10-coded electronic health record and claims data: an observational study

• Published in: BMJ open Vol. 14; no. 2; p. e074390
• Main Authors: Wei, Melissa Y, Leis, Aleda M, Vasilyev, Arseniy, Kang, Ashley J
• Format: Journal Article
• Language: English
• Published: England British Medical Journal Publishing Group 15.02.2024; BMJ Publishing Group LTD; BMJ Publishing Group
• Series: Original research
• Subjects: Adolescent; Adult; Aged; Chronic Disease; Chronic illnesses; Codes; Comorbidity; Disease; Electronic Health Records; EPIDEMIOLOGY; Female; GENERAL MEDICINE (see Internal Medicine); Health care policy; Health Services Research; Humans; INTERNAL MEDICINE; International Classification of Diseases; Male; Medical referrals; Middle Aged; Mortality; Multimorbidity; Observational studies; Patient-Centered Care; Retrospective Studies; GENERAL MEDICINE (see Internal Medicine); Chronic Disease; Electronic Health Records; Patient-Centered Care; EPIDEMIOLOGY; INTERNAL MEDICINE
• ISSN: 2044-6055; 2044-6055
• DOI: 10.1136/bmjopen-2023-074390

ObjectiveMap multimorbidity-weighted index (MWI) conditions to International Classification of Diseases, 10th Revision (ICD-10), expand the conditions and codes to develop a new ICD-10-coded MWI (MWI-ICD10) and updated MWI-ICD9, and assess their consistency.DesignPopulation-based retrospective cohort.SettingLarge medical centre between 2013 and 2017.ParticipantsAdults ≥18 years old with encounters in each of 4 years (2013, 2014, 2016, 2017).Main outcome measuresMWI conditions mapped to ICD-10 codes, and additional conditions and codes added to produce a new MWI-ICD10 and updated MWI-ICD9. We compared the prevalence of ICD-coded MWI conditions within the ICD-9 era (2013–2014), within the ICD-10 era (2016–2017) and across the ICD-9–ICD-10 transition in 2015 (washout period) among adults present in both sets of comparison years. We computed the prevalence and change in prevalence of conditions when using MWI-ICD10 versus MWI-ICD9.Results88 175 adults met inclusion criteria. Participants were 60.8% female, 50.5% white, with mean age 54.7±17.3 years and baseline MWI-ICD9 4.47±6.02 (range 0–64.33). Of 94 conditions, 65 had <1% difference across the ICD-9–ICD-10 transition and similar minimal changes within ICD coding eras.ConclusionsMWI-ICD10 captured the prevalence of chronic conditions nearly identically to that of the validated MWI-ICD9, along with notable but explicable changes across the ICD-10 transition. This new comprehensive person-centred index enables quantification of cumulative disease burden and physical functioning in adults as a clinically meaningful measure of multimorbidity in electronic health record and claims data.