Definition/Introduction

Instrumental activities of daily living (IADL) are those activities that allow an individual to live independently in a community. Although not necessary for functional living, the ability to perform IADLs can significantly improve the quality of life. The major domains of IADLs include cooking, cleaning, transportation, laundry, and managing finances. Occupational therapists commonly assess IADLs in the setting of rehab to determine the level of an individual’s need for assistance and cognitive function.

IADLs are commonly confused with basic activities of daily living (ADLs). The major domains of ADLs are feeding, dressing, bathing, and walking. In contrast with IADLs, ADLs are necessary for basic functional living. Deficits in performing ADLs may indicate the need for home healthcare or placement in a skilled nursing facility.[1]

Issues of Concern

There exist multiple scales or instruments for the evaluation of IADLs. These include, but are not limited to, Lawton and Brody IADL, Health and Retirement Study Care Questionnaire, and Pfeffer Functional Activities Questionnaire. Each instrument includes its definition of IADL disability. Therefore, in analyzing cognitive impairment, the results differ depending on which instrument the evaluator used.

One of the significant limitations that all these instruments have in common is that they are often self-reported. A person is biased toward his or her abilities to perform specific tasks. Thus, they may either overestimate or underestimate their abilities. 

Another major issue arises when examiners use IADL instruments to detect the probability of dementia in mildly cognitive impaired (MCI) individuals. Studies have shown that there is no difference in performing certain IADLs between MCI individuals with dementia and MCI individuals without dementia, which may be because current instruments are not sensitive to subtle changes. For example, an individual may have no issues with driving but have trouble adhering to traffic laws. On the Lawton and Brody IADL questionnaire, this individual would receive full points in evaluating the mode of transportation. Although current IADL instruments are widely helpful, they may still require a few refinements.[2][3][4][5]

Clinical Significance

Despite some limitations, the assessment of IADLs remains useful in determining the cognitive function of an individual. Individuals with MCI who have impairments performing IADLs are more likely to develop dementia. The ability to perform IADLs is the first to decline in individuals with Alzheimer disease, while the ability to perform basic activities remains unimpaired. This finding can be helpful to healthcare professionals in detecting early-onset Alzheimer and dementia. 

In most hospitals, the interdisciplinary approach to healthcare has become a popular concept. In rehab facilities, the physician, nurses, occupational therapists, and physical therapists work together to share knowledge and patient care skills. As stated before, occupational therapists generally assess ADLs and IADLs. Reports from occupational therapists can help analyze the functional and mental status of the patient. Studies have shown physical disability is a strong risk factor for cognitive decline. Thus, physicians and occupational therapists need to work closely together to minimize the risk of physical disability to limit cognitive decline. Understanding the importance of assessing ADLs and IADLs is crucial, as it can be a useful screening tool for dementia in the elderly population.[6][7][8][9][10]

Nursing, Allied Health, and Interprofessional Team Interventions

Nursing staff and other home health aides can assist patients with IADLs, including cooking, cleaning, laundry, and even managing finances. These services can be provided in various facility arrangements, from nursing homes to home care.