Climate change expected to disproportionately affect older adults

Gamble J, Hurley B, Schultz P, Jaglom W, Krishnan N, Harris M. Climate change and older Americans: State of the science Environmental Health Perspectives. 2013; 121(1): 15-22.

Review question

•      What is the impact of climate change on older adults in the United States?

Background

•      As the population of older adults rises globally, as is the impact of climate change, bringing with it increasing temperatures risk of floods, wildfires, and droughts.

•      Previous studies have indicated that older adults are especially vulnerable to the stressors associated with climate change.

•      This vulnerability is associated with a number of physiological, psychological, and socioeconomic factors, including the higher prevalence of certain diseases and functional impairments among older adults, their higher sensitivity to extreme temperatures, their increased social isolation, and their unique financial status.

•      This systematic review provides an overview of the research examining impacts of climate change on older adults in the United States. A specific emphasis is placed on key climate stressors, factors influencing the capacity of older Americans to adapt to climate stressors, and measures that can be undertaken to enhance the resilience of older adults to climate change.

How the review was done

•      Review authors conducted a search of two research databases for eligible studies. Major synthesis reports were also reviewed to identify relevant citations.

•      Studies reporting on a variety of topics relating to the research question were eligible for inclusion, including population demographics, relevant climate stressors, factors contributing to the vulnerability of older adults, and response strategies to climate change.

•      To be included, studies had to be published between 2000 and 2011.

•      In total, 430 articles were retrieved from the initial search, of which 94 were included in this review.

•      Several authors of this review were employed at ICF International, a technology, policy, and management consultancy in Washington, DC. The authors declare no actual or potential competing financial interests.

What the researchers found

•      The findings from this review were thematically organized into six themes: demographic factors that influence the vulnerability of older adults; physiological factors that influence the sensitivity of older adults to climate stressors; climate stressors that disproportionately affect older adults; factors determining exposure to climate stressors; determinants of older adults’ adaptive capacity; and reducing vulnerability through effective adaptation.

•      Under the theme of demographic factors that influence the vulnerability of older adults, reviewers found that some locations with growing older adult populations are more likely to be affected by climate stressors such as hurricanes, floods, droughts, rising summer temperatures, and infectious disease. Among the at-risk states are California, Florida, New York, Texas, and Pennsylvania, where 51.2% of Americans aged 65 or older lived in 2008. The results seemed to indicate a higher concentration of low-income older adults in at-risk locations. Urban location is also considered a risk factor for vulnerability to climate stressors due to the exacerbation of summer heat by the urban heat island effect.

•      Physiological factors that influence the sensitivity of older adults to climate stressors are due in large part to the natural aging process, which predisposes older adults to increased risk of certain diseases and disorders, as well as changes in social factors such as increased social isolation and income loss. Due to the increase in atmospheric concentrations of fine particulates like dust and allergenic pollen associated with climate change, individuals with respiratory impairments may be more at-risk in drought-prone areas. Heart disease can also make older adults more sensitive to health complications from warmer summers, heat waves, and air pollution.

•      Climate stressors found to disproportionately impact older adults include extreme heat, air pollution, infectious disease exacerbations, hurricanes, floods, droughts, and other extreme weather events.

•      Several factors were found to affect the degree to which older Americans will be exposed to climate stressors; these included socioeconomic characteristics, housing characteristics, adequacy of neighborhood infrastructure, and availability of social services.

•      Key determinants of older adults’ adaptive capacity included functional limitations and mobility impairments, economic status, living situation, technological savviness, and the availability of social supports.

•      In order to reduce the vulnerability of older adults to climate change, three strategies were found to be particularly useful: 1) information and education to older adults; 2) strengthening community infrastructure and capabilities; and 2) creating tools and preemptive measures to improve adaptation and lessen vulnerability.

Conclusion

•      Research has demonstrated that older American adults are likely to be especially vulnerable to stressors associated with climate change.

•      Although a growing amount of evidence reports the adverse effects of heat on the health of older adults, research gaps remain for other climate-related risks.

•      Additional research is needed in the study of the vulnerability of older adults and the interplay between vulnerability, resilience, and adaptive responses to climate stressors.