b'CHAPTER 2 | THE AGING BRAINOther research aims to determine the dollarto the financial burden. Compared with cognitive value of the informal caregiving provided toimpairment or depression alone, cognitive impair- Despite growing numbers of those with dementia. Before ADAMS data werement plus depression is associated with greater available, Langa et al. (2001) performed this cal- costs (Xiang and An 2015b). people with cognitive impairment, culation with HRS by using measures of cognitivesocial, medical and demographic functioning that approximated mild, moderatePositive Trends trends may have a positive impact and severe dementia, and estimated the hours ofDespite growing numbers of people with on cognitive health.care provided in each category. A common way tocognitive impairment, social, medical andmeasure the cost of informal care is to think ofdemographic trends may have a positive impact it as the foregone potential wages the caregiveron cognitive health. Two positive outcomes are Langa et al. (2008) used HRS data on cog-could have earned if he or she were not providingpossible: 1) decreasing prevalence of dementianitive functioning to investigate both of these care. Another way to estimate this opportu- over time and 2) delayed onset of clinical symp- possibilities. They find that the prevalence of nity cost is to assign it the value of the cost oftoms of dementia. The latter refers to the goal cognitive impairment consistent with dementia equivalent services, such as a home health aide.of reducing the duration of illness for chronic declined from 12.2% in 1993 to 8.7% in 2002. They find the number of hours of care rises verydiseases that lead to death by delaying diseaseEarlier research shows that higher levels of sharply progressing from mild to severe demen- onset, so-called morbidity compression. education and wealth are linked to lower levels tiafrom 8.5 to 41.5 additional hours of care perof dementia. Indeed, they find that increasing week (compared to those with normal cognition).education and net worth over time and between The cost of this care is substantial as well. FIGURE 2-8Costs of caring for personscohorts accounts for about 40% of the decrease in Combining all sources of cost informationwith dementia, by source of payment: 2010 prevalence. They also compare two-year mortality informal care, formal in-home care and nursingSource: Hurd et al. (2013) rates between the two cohorts to investigate the home careinto one analysis can yield an$250 question of morbidity compression and find that Billions of dollarsestimate of the total cost of dementia to the USthose with moderate to severe cognitive impair-economy (Hurd et al. 2013). Figure 2-8 summa- ment have a significantly higher risk of death in rizes costs across several categories. The total cost$200 $482002 than in 1993.of dementia in 2010 was between $161 billion and $221 billion, depending on how the cost of in- $150 Is Cognitive Reserve the Key? $64 formal care is calculated. The size of this estimateThe finding that higher levels of education are means that dementia has a social and economicassociated with increased two-year mortality for $100impact as large as other important and commonthose with cognitive impairment in both time pe-chronic diseases, such as heart disease and cancer.riods (1993 and 2002) is actually good news and Kelley et al. (2015) also show that, in the last five$50 $109lends support to the concept of cognitive reserve. years of life, health care expenditures for thoseAccording to this hypothesis, greater mental with dementia are much larger than the cost asso- stimulation, which is associated with education, ciated with other diseases. They show that these$0 leads to increased neuronal development and an large OOPM expenses are born by those who areGovernment increased number of connections among brain least prepared for financial risk. Depression addsPrivate market cells, and thus greater brain capacity. Brains with Family non-market47'