Coding for intellectual, developmental disabilities


Intellectual and developmental disability (IDD) is typically used to describe a person in whom intellectual and other types of disabilities coexist. Intellectual disability is usually identified by an IQ less than 70 and is associated with adaptive behavior problems beginning before age 18.

Adaptive behavior includes: conceptual skills such as language, literacy, and self-direction; social skills; and practical skills like activities of daily living, occupational skills, and safety skills. Developmental disability is a broad category of long-term physical and/or mental disability identified before age 22.

A large number of clinical conditions may be associated with intellectual disability (ID); Table 1 shows the most common. Many patients with autism and cerebral palsy do not have intellectual disability but are mistakenly thought to be intellectually disabled because they have impaired verbal communication. Other comorbid conditions are common in IDD patients, who are typically vulnerable to many types of medical complications.

Coding and documentation challenges

“Intellectual disability” is the preferred clinical terminology, and it is categorized by severity (see Table 2). The underlying cause of intellectual disability should also be identified and is separately coded as an additional diagnosis.

With cerebral palsy patients, the documentation of the degree of paralysis associated with the disease is crucial, as it impacts the severity-of-illness classification: monoplegic, paraplegic/diplegic, hemiplegic, or quadriplegic/tetraplegic. Neonatal hypoxic ischemic encephalopathy (HIE) of any degree or anoxic (hypoxic) brain damage are also diagnostically important and can lead to intellectual disability.

Functional quadriplegia

Some patients with intellectual disability have co-existing, severe physical disabilities requiring total care. An assessment of activities of daily living will indicate a high degree of disability or total dependence for such measures as: communication, ambulation, transferring, dressing, eating, swallowing, toileting and bathing. The Braden scale measures for pressure ulcer risk and will typically show immobility or very limited mobility and bedfast or chair-fast states.

Pressure ulcers may occur in such patients and must be identified and documented at the point of admission. Otherwise, treatment may be suboptimal and may be classified as hospital-acquired, having quality of care implications and potential financial penalties. Stage 3 and 4 pressure ulcers, when recognized as present on admission, have high severity-of-illness impact and substantial revenue impact since they greatly complicate care and often prolong hospitalization.

Acute metabolic or toxic encephalopathy

Patients with intellectual and developmental disabilities often have variable degrees of baseline mental impairment but are also vulnerable to acute encephalopathy due to metabolic, toxic, or other systemic stress.

Acute encephalopathy is characterized by a generalized functional (non-structural), reversible alteration in baseline mental function due to a systemic underlying cause. Encephalopathy can be easily recognized in these patients when there is a demonstrable generalized alteration in brain function that clearly returns to baseline when the underlying systemic cause is corrected.

Metabolic factors include fever, infection, sepsis, dehydration, electrolyte imbalance, hypoxemia, and acute organ dysfunction. Toxic encephalopathy is intended to describe the effects of medications, drugs, toxins and chemicals. Toxic-metabolic usually describes a combination of toxic and metabolic factors.

The clinical definitions of delirium and encephalopathy may be considered essentially the same, but encephalopathy more accurately reflects the severity of illness in these patients. Coding rules and guidelines primarily classify delirium as a symptom having little or no severity impact. For example, drug-induced delirium is clinically equivalent to toxic encephalopathy and “acute delirium due to UTI and dehydration” is comparable to metabolic encephalopathy.

Counseling and coordination of care

Patients with intellectual disability often require time-intensive efforts for communication and coordinating care. Clinicians commonly must contact caregivers for information, and caregivers and patients require detailed care instructions. In such situations, counseling and/or coordination of care may comprise more than 50% of total time spent providing all hospital services on a given date. When properly documented, total unit/floor time is considered the key factor to qualify for a particular level of Evaluation and Management (E/M) service. The level of service is then based on the average time that CPT® codes assign to the E/M service (see Table 3).

In summary, caring for patients with an intellectual or developmental disability poses unique challenges. Documentation of severity and/or the associated IQ is required for correct coding and severity-of-illness assignment. Several common comorbidities and complications also have great significance. Time-intensive counseling and/or coordination of care with IDD patients and caregivers is often required and may permit clinicians to base E&M severity levels on total time.