Page 1 Page 2 Page 3 Page 4 Page 5 Page 6 Page 7 Page 8 Page 9 Page 10 Page 11 Page 12 Page 13 Page 14 Page 15 Page 16 Page 17 Page 18 Page 19 Page 20 Page 21 Page 22 Page 23 Page 24 Page 25 Page 26 Page 27 Page 28 Page 29 Page 30 Page 31 Page 32 Page 33 Page 34 Page 35 Page 36 Page 37 Page 38 Page 39 Page 40 Page 41 Page 42 Page 43 Page 44 Page 45 Page 46 Page 47 Page 48 Page 49 Page 50 Page 51 Page 52 Page 53 Page 54 Page 55 Page 56 Page 57 Page 58 Page 59 Page 60 Page 61 Page 62 Page 63 Page 64 Page 65 Page 66 Page 67 Page 68 Page 69 Page 70 Page 71 Page 72 Page 73 Page 74 Page 75 Page 76 Page 77 Page 78 Page 79 Page 80 Page 81 Page 82 Page 83 Page 84 Page 85 Page 86 Page 87 Page 88 Page 89 Page 90 Page 91 Page 92 Page 93 Page 94 Page 95 Page 96 Page 97 Page 98 Page 99 Page 100 Page 101 Page 102 Page 103 Page 104 Page 105 Page 106 Page 107 Page 10847 CHAPTER 2 | THE AGING BR AIN Other research aims to determine the dollar value of the informal caregiving provided to those with dementia. Before ADAMS data were available, Langa et al. (2001) performed this cal- culation with HRS by using measures of cognitive functioning that approximated mild, moderate and severe dementia, and estimated the hours of care provided in each category. A common way to measure the cost of informal care is to think of it as the foregone potential wages the caregiver could have earned if he or she were not providing care. Another way to estimate this opportu- nity cost is to assign it the value of the cost of equivalent services, such as a home health aide. They find the number of hours of care rises very sharply progressing from mild to severe demen- tia — from 8.5 to 41.5 additional hours of care per week (compared to those with normal cognition). The cost of this care is substantial as well. Combining all sources of cost information — informal care, formal in-home care and nursing home care — into one analysis can yield an estimate of the total cost of dementia to the US economy (Hurd et al. 2013). Figure 2-8 summa- rizes costs across several categories. The total cost of dementia in 2010 was between $161 billion and $221 billion, depending on how the cost of in- formal care is calculated. The size of this estimate means that dementia has a social and economic impact as large as other important and common chronic diseases, such as heart disease and cancer. Kelley et al. (2015) also show that, in the last five years of life, health care expenditures for those with dementia are much larger than the cost asso- ciated with other diseases. They show that these large OOPM expenses are born by those who are least prepared for financial risk. Depression adds to the financial burden. Compared with cognitive impairment or depression alone, cognitive impair- ment plus depression is associated with greater costs (Xiang and An 2015b). Positive Trends Despite growing numbers of people with cognitive impairment, social, medical and demographic trends may have a positive impact on cognitive health. Two positive outcomes are possible: 1) decreasing prevalence of dementia over time and 2) delayed onset of clinical symp- toms of dementia. The latter refers to the goal of reducing the duration of illness for chronic diseases that lead to death by delaying disease onset, so-called morbidity compression. Langa et al. (2008) used HRS data on cog- nitive functioning to investigate both of these possibilities. They find that the prevalence of cognitive impairment consistent with dementia declined from 12.2% in 1993 to 8.7% in 2002. Earlier research shows that higher levels of education and wealth are linked to lower levels of dementia. Indeed, they find that increasing education and net worth over time and between cohorts accounts for about 40% of the decrease in prevalence. They also compare two-year mortality rates between the two cohorts to investigate the question of morbidity compression and find that those with moderate to severe cognitive impair- ment have a significantly higher risk of death in 2002 than in 1993. Is Cognitive Reserve the Key? The finding that higher levels of education are associated with increased two-year mortality for those with cognitive impairment in both time pe- riods (1993 and 2002) is actually good news and lends support to the concept of cognitive reserve. According to this hypothesis, greater mental stimulation, which is associated with education, leads to increased neuronal development and an increased number of connections among brain cells, and thus greater brain capacity. Brains with FIGURE 2-8 Costs of caring for persons with dementia, by source of payment: 2010 Source: Hurd et al. (2013) Government Private market Family non-market $109 $64 $48 $0 $50 Billions of dollars $100 $150 $200 $250 Despite growing numbers of people with cognitive impairment, social, medical and demographic trends may have a positive impact on cognitive health.