Internal Medicine Coding Alert

Question: We saw an obese patient who has been abusing laxatives to lose weight. The physician counseled the patient about the dangers of laxative abuse. I am trying to code the diagnosis, but it requires a fifth digit that defines continuous, episodic, or remission. I can't seem to find a definition for these fifth-digit terms. Can you help?

Louisiana Subscriber

Answer: The fifth-digit definition for continuous is "daily intake of large amounts of the substance or regular heavy use on weekends and days off from work." Episodic is defined as "binges lasting weeks or months, followed by long periods of abstinence." Remission is defined as "either complete cessation of drug intake for a period of up to twelve months or the period during which a decrease toward cessation is taking place." The period during which a decrease toward cessation is taking place is defined as between one full month of abstinence and 12 months of abstinence of use of the substance. As you can see, coding from the mental-disorder section is complicated and not something you are apt to be able to do correctly from a description on a charge ticket.

When confronted with coding a mental disorder, locate the definition of the terms your internist has used from one of the resources listed above and present the information to the physician so that he or she may verify that the assignment of a mental-disorder code is warranted under the diagnostic coding criteria. In the instance that you site, if the patient did not meet the full criteria for abuse, a V code such as V65.3 (Dietary surveillance and counseling) combined with 278.00 (Obesity, unspecified) or 278.01 (Morbid obesity) would be more appropriate. Another V code alternative might be V65.42 (Counseling on substance use and abuse) and the obesity code. In both of these instances, sequence the obesity code first and the V code second.

Assigning codes from the mental-disorders section of ICD-9 can be a challenge, especially for internal medicine coders who do not use these codes frequently. When determining if a mental-disorder code should be used, start in the appendix of your ICD-9 manual. Appendix B contains a glossary of mental disorders. As stated in the IDC-9 manual, drug abuse is defined as "cases where an individual, for whom no other diagnosis is possible, has come under medical care because of the maladaptive effect of a drug on which he is not dependent and that he has taken on his own initiative to the detriment of his health or social functioning."

Because of the sensitivity and social stigma that are associated with mental disorders, the coder should review these definitions in the appendix with the treating physician before assigning one of these codes. Although your physician may have used the terminology "abuse" as an internist, he may not be familiar with the ICD-9 definition of that term. Often the terminology in the mental-disorder section is used more loosely in daily life than is intended by the ICD-9 definition of the code. Although the patient may be taking laxatives improperly to promote weight loss, he or she may not meet the formal criteria of abuse if there has not yet been a detrimental effect on his or her health or social functioning.