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 10843 CHAPTER 2 | THE AGING BR AIN Those who say they did well in school, regardless of the level completed, have a much lower risk of being diagnosed with Alzheimer’s disease later in life. Another study uses ADAMS to investigate educational quality as an independent risk for dementia later in life (Mehta et al. 2009). Below- average self-assessed school performance is asso- ciated with a four-fold risk of AD independent of educational level, literacy score, and other relevant risk factors. Educational level attained is an im- portant asset, but educational quality may do even more to build cognitive capacity. Those who say they did well in school, regardless of the level com- pleted, have a much lower risk of being diagnosed with AD later in life. These findings suggest that merely staying in school may not result in the full benefits of education for dementia risk. Medical Risks Medical risks are a promising area of investiga- tion, especially given that their identification has great potential for intervention to reduce the burden of the medical risk itself as well as poten- tially associated dementia. Llewellyn et al. (2010) examine hypertension, heart disease, diabetes, stroke, APOE e4, and dementia risk. Supplemen- tal information, such as medication use, allows researchers to assign treated versus untreated status to each of the four medical conditions investigated. Both treated and untreated stroke and APOE e4 allele significantly elevate dementia risk. Treated hypertension decreases dementia risk. Interestingly, heart disease and diabetes are not associated with dementia. The interaction of APOE e4 allele with stroke confers very high risk for dementia. D. Levine et al. (2015) find that race differences in cognition and cognitive decline are not explained by differences in the higher stroke risk for African Americans compared to Whites. Building on clinical research findings that visual problems are associated with cognitive impairment, Rogers and Langa (2010) investigate the role of visual impairment in the development of dementia. They follow ADAMS participants for 8.5 years to see if changes in vision are associated with changes in cognitive functioning. HRS data are also linked with Medicare treatment records to estimate the effects of vision procedures like corneal transplant or cataract removal/lens implantation. Those diagnosed with dementia, especially AD, have poorer vision at baseline and have received fewer eye services prior to their di- agnosis than those who do not experience serious cognitive decline. Uncorrected poor vision is a very significant risk factor for dementia. HRS findings show that acute health events may also lead to cognitive decline. Severe sepsis, or blood infection, is a major cause of critical illness requiring hospitalization. Information on hospitalization for severe sepsis was obtained from linked Medicare data (Iwashyna et al. 2010) and used to identify HRS participants who had an episode of severe sepsis. Severe sepsis is associat- ed with substantial and persistent new cognitive impairment and functional disability among survivors. Figure 2-6 shows that among those who survive severe sepsis, 6.1% had moderate to severe cognitive impairment at the last survey prior to the episode of sepsis. This percentage increased to 16.7% by the first survey after the episode and persisted even two years later. Severe sepsis episode has no impact on changes in MCI. 0% 2% 4% 6% 8% 10% 12% 14% 16% -4 yrs -2 yrs 2 yrs 4 yrs Time to and since sepsis episode Mild cognitive impairment Moderate to severe cognitive impairment Before sepsis After sepsis FIGURE 2-6 Percent of patients with cognitive impairment before and after severe sepsis: 1998-2006 Source: Iwashyna et al. (2010).