Comorbidity	ICD-9-CM Diagnosis Codes
Opioid abuse and dependence
Opioid type dependence	304.0x
Combinations of opioid type drug with any other drug dependence	304.7x
Nondependent opioid abuse	305.5x
Poisoning by opiates and related narcotics	965.0x (excluding 965.01 for poisoning by heroin)
Components of the Charlson Comorbidity Index
Myocardial infarction	410.xx, 412.xx
Congestive heart failure	402.01, 402.11, 402.91, 404.01, 404.03, 404.11, 404.13, 404.91, 404.93, 425.xx, 428.xx, 429.3x
Peripheral vascular disease	440.xx-442.xx, 443.1x-443.9x, 447.1x, 785.4x
Cerebrovascular disease	362.34, 430.xx-436.xx, 437.0x-437.1x, 437.9x, 438.xx, 781.4x, 784.3x, 997.0x
Dementia	290.xx, 331.0x-331.2x
Chronic pulmonary disease	415.0x, 416.8x, 416.9x, 491.xx-494.xx, 496.xx
Rheumatologic disease	710.xx, 714.xx
Peptic ulcer disease	531.xx-534.xx
Mild liver disease	571.2x, 571.5x, 571.6x, 571.8x, 571.9x
Diabetes	250.0x-250.3x
Diabetes with chronic complications	250.4x-250.9x
Hemiplegia or paraplegia	342.xx, 344.xx
Renal disease	585.xx-586.xx, V42.0x, V45.1x, V56.xx
Any malignancy including leukemia and lymphoma	140.xx-171.xx, 174.xx-195.xx, 200.xx-208.xx, 273.0x, 273.3x, V10.46
Moderate or severe liver disease	572.2x-572.4x, 456.0x-456.2x
Metastatic solid tumor	196.xx-199.xx
AIDS	042.xx-044.xx
Other selected comorbidities
Nonopioid substance abuse diagnoses	303.xx, 304.1x-304.6x, 304.8x-304.9x, 305.0x-305.4x, 305.6x-305.9x, V11.3
Psychotic disorders	290.xx-299.xx, V11.0-V11.1
Other mental disorders	300.xx-302.xx, 306.xx-319.xx, V11.2, V11.8-V11.9

AIDS = acquired immune deficiency syndrome; ICD-9-CM = International Classification of Diseases, Ninth Revision, Clinical Modification.