Background and significance
An increasing number of older adults are choosing to live independently in the community; consequently the number of people entering skilled nursing facilities is steadily declining. More and more lifestyle living apartments and assisted living facilities are housing older adults and senior citizens (Kinosian, Stallard, & Wieland, 2007). The terms older adults, elderly, and senior citizens are often used interchangeably in the literature. For the purpose of this review, older adult is defined as anyone over the age of 65.
More than 30% of people aged 65 and older fall at least once a year with many hospitalized due to a falls-related accident (Arnold & Faulkner, 2007; Boulgarides, McGinty, Willett, & Barnes, 2003). In the United States, averages of 1.8 million falls resulting in nonfatal injuries were reported in 2006 among the older adult population (Centers for Disease Control and Prevention (CDC), 2006). Falls make up the largest percentage of accidents among the elderly and falling is a leading cause of accidental death second only to automobile accidents (CDC, 2006; Huang, Gau, Lin, & Kernohan, 2003). Due to the declining health of many older adults, falls (fatal or nonfatal), often require emergency medical care. Even when no injury occurs, multiple falls invariably trigger changes in lifestyle, reduction in physical and social activities, reduced independence in activities of daily living (ADL), increased social isolation, and a reduction in quality of life (Kron, Loy, Strum, Nikolaus, & Becker, 2003).
This literature review highlights the role of indoor light levels and their effect on falls and daily function among community dwelling older adults. Research implications for the body of knowledge of occupational therapy and occupational science are highlighted.
Light levels and human performance
Light levels in the environment often interact with human physiology and function. In spite of the necessity of adequate lighting for sight and safety, data shows that artificial lighting levels in many residences and nursing homes in the United States are below the American National Standards Institute (ANSI) recommended levels (Bakker, Lofel, & Lachs, 2004;. De Lepeleire, Bouwen, De Coninck, & Buntinx, 2007; Hegde, & Rhodes, 2010).
A comparative study by Hamel, Okita, Higginson, and Cavanagh (2005) looked at falls and trips, and stair clearance behaviour between healthy young adults and healthy older adults at different light levels. Older adults sustained more trips and slips than their younger counterparts in all lighting conditions. Interestingly, it was noted that older adults did not increase the clearance between their feet and the stairs in low light conditions since high clearance of feet is often seen as a safety tactic used on stair clearance in dark conditions. This lack of clearance could be implicated in fall-related stairwell accidents at night time and in low light conditions (Hamel et al., 2005).
A recent study by Brown and Jacobs (2011) examined the relationship between self-reported inadequate residential natural light and risk for depression and falls among adults aged 18 years and older. Results showed that participants reporting inadequate natural light in their residences were 1.4 times as likely to report depression and 1.5 times as likely to report a fall when compared with those satisfied with the light levels in their homes. Furthermore, building-related factors were found to contribute to falls. These factors included lack of handrails in stairwells, inadequate or irregular stair dimensions and stair coverings, poor maintenance of buildings, inadequate lighting, and visual distractions (Brown & Jacobs, 2011).
Reed, Lowrey and Vallis (2006) undertook a study to compare two age groups, middle-old (age 75-84) and old-old (age 85-94) on mobility using an obstacle course under normal and lower than normal lighting conditions. …