Unilateral neglect (UN) is a debilitating cognitive deficit following traumatic brain injury with long-term implications to both the person affected and the health care system. In the United States, UN affects up to 200,000 stroke survivors, with the incidence and severity of UN increasing with age. However, UN is rarely recognized by the health care team and current post-stroke testing is not specific enough to provide for a definitive diagnosis of UN. As a result, people with UN are under-diagnosed and under-treated; or, when diagnosed and treated, do not receive adequate rehabilitation due to financial constraints imposed by the Medicare system.

UN is most common following damage to the right hemisphere of the brain from stroke; although illness or traumatic brain injury are also linked to the development of UN. When functioning normally, the right hemisphere of the brain is attentive to both sides of the world with a global focus and the ability for prolonged attention while the left hemisphere is attentive only to its opposite side with a centralized focus and shorter attention span.

The wide range and complexity of UN symptoms and the presence of other sensory or motor deficits due to stroke contributes to the high rate of missed diagnoses. A disorder of input and/or output, a person affected with UN will either completely ignore the side opposite to the brain injury or feel that side is totally unimportant; to the extent of not recognizing their own limbs. All deficits are more severe in those affected by UN following stroke and are more likely to be permanent than in people who do not have UN in conjunction with stroke.

People with UN are able to see, hear, and move but do not recognize, listen to, or understand their world. A person with input disorder, also called inattention, will ignore odors, sounds, touch, and sight on the side opposite to their brain lesion; this inattention may also include ignoring one side of hallucinations, dreams or memories. A person with output disorder will not use their limbs opposite to the lesion, despite having the ability to do so; or will only be able to move a limb within the recognized space, but not within the ignored space.

A person with UN will ignore the left side of their visual field, or will be able to see both sides but ignore the left half of each object within the visual field. They will only dress or care and protect one side of their body; will only eat food on one side of their plate; will only look to one side; will completely ignore objects or people on the affected side; or will walk into walls or furniture on the effected side. People are usually unaware of the presence of their deficits due to UN, unlike when other sensory and motor deficits are present following stroke.

Inpatient rehabilitation facilities receive a set amount of money from Medicare, based upon guidelines for each illness or disease. These prospective payment systems limit a patient’s length of stay regardless of their level of functioning upon discharge and have been found to have an impact upon the outcome of people with UN. A person affected with UN does not progress quickly during rehabilitation, requires a long time to recover, and is discharged with a low level of functioning. In addition, people with UN are less likely to return to their homes and live on their own following stroke, and have an increased risk for falls or other injuries.

People are now living longer; the incidence and severity of UN will continue to rise, straining an already overburdened health care system. UN has impacted the elderly today and will have an impact upon aging baby boomers in the very near future. Additional research is needed to ensure early and accurate diagnosis through appropriate testing methods; targeted and effective treatment modalities need to be developed; and the health care team must be educated to increase awareness of this often neglected complication of stroke. Modification of the prospective payment system within the current Medicare system is also needed that recognizes the increased rehabilitation requirements for this group of stoke and brain injury survivors.

References

Gillen R et al. The impact of the inpatient rehabilitation facility prospective payment system on stroke program outcomes. Am J Phys Med Rehabil. 2007 May; 86 (5): 356-63. doi:  10.1097/PHM.0b013e31804a7e2f

Gottesman RF et al. Unilateral neglect is more severe and common in older patients with right hemispheric stroke. Neurology. 2008 Oct 28;71(18):1439-44. doi: 10.1212/01.wnl.0000327888.48230.d2

Jepson R et al. Unilateral Neglect: Assessment in Nursing Practice. J Neurosci Nurs. 2008 Jun; 40 (3): 142-9.

Wee, J., & Hopman, W. (2008). Comparing Consequences of Right and Left Unilateral Neglect in a Stroke Rehabilitation Population American Journal of Physical Medicine & Rehabilitation, 87 (11), 910-920 DOI: 10.1097/PHM.0b013e31818a58bd