Cognition in aging

1. Cognition in Aging Clifford Gonzales CRNA, PhD

2. Cognition in Aging Identify cognitive functions List age-related changes in cognitive functions Identify activities promoting healthy cognitive functions POCD vs POD Name precipitating variables of POCD Strategies minimizing POCD

3. Cognitive Functions Working memory Processing speed Inhibition Sensory system

4. Working Memory 12 in 2mmhg/in

5. Working Memory Store= 12 in; 2mmhg/in Processing= 12 x 2= 24 mmhg Store= 24mmhg Look at current blood pressure= 100/65 mmhg Retrieve the 24mmhg Processing= 100-24 and 65-24= 76/41 Compare 20% threshold

6. Cognitive Functions Working memory Processing speed Inhibition Sensory system

7. Inhibition

8. Sensory System

9. Cognition in Aging Identify cognitive functions List age-related changes in cognitive functions Identify activities promoting healthy cognitive functions POCD vs POD Name precipitating variables of POCD Strategies minimizing POCD

10. Age-Related Changes Brain atrophy= 0.35% per year @ 50 y/o 1 Ventricular hypertrophy= 2.9% per year @ 70 y/o 2 Hippocampal atrophy= ave of <1 % (26-82y/o) 3 Pruning of white matter

11. Age-Related Changes Mortimer JA, Snowdon DA, Markesberry WR. Neuropsychology. 2003 1 Scarmeas N, Albert SM, Manly JJ, Stern Y. J Neurol Neurosurg Psychiatry. 2006 2

12. Cognitive Reserve Theory

13. Cognitive Reserve Theory Clinical Expression of Cognitive Impairment CNS lesions White matter lesions Brain atrophy Plaques & tangles Vascular damage Metabolic/endocrine diseases Injury Influencing factors Genes Lifestyle factors (education, occupation,social , physical, & leisure activities) Brain size and function Neural network density and complexity Processing capacity and efficiency Premorbid Cognitive ability Other influences on cognitive impairment prevention Personality Health service delivery and uptake Richards M, Deary IJ. Annals of Neurology. 2005 3

14. Cognition in Aging Identify cognitive functions List age-related changes in cognitive functions Identify activities promoting healthy cognitive functions POCD vs POD Name precipitating variables of POCD Strategies minimizing POCD

15. Healthy Cognitive Functions Physical activity 150 min (moderate) or 75min (vigorous) aerobic + muscle strengthening Decrease sympathetic stimulation Maintenance of brain structures 4,5

16. Healthy Cognitive Functions Leisure Activity Activities more on life satisfaction Productive vs consumptive Effect on white matter 6,7 Associated with working memory, episodic memory, and processing speed.

17. Healthy Cognitive Functions Socialization Associated with working memory and processing speed 8

18. Cognition in Aging Identify cognitive functions List age-related changes in cognitive functions Identify activities promoting healthy cognitive functions POCD vs POD Name precipitating variables of POCD Strategies minimizing POCD

19. Cognitive Impairment Postoperative delirium- acute fluctuation of the state of orientation and attention. Postoperative cognitive dysfunction- alteration in learning, memory, abstract thinking, and concentration after surgery.

20. Cognition in Aging Identify cognitive functions List age-related changes in cognitive functions Identify activities promoting healthy cognitive functions POCD vs POD Name precipitating variables of POCD Strategies minimizing POCD

21. Postoperative Cognitive Dysfunction Predisposing factors: Age Co-morbidities: presence of cognitive impairment Precipitating factors Stress Cell injury

22. Stress

23. Cell Injury Precursors of Alzheimer’s dse Inflammatory markers/receptors

24. Alzheimer’s Dse Temperature induced

25. Inflammatory Markers/Receptors Microglial activation-release of TNF-a NMDA receptors-protein changes lead to spatial learning impairment

26. Neuroprotection vs Neurotoxicity Type of surgery Type of anesthesia RA vs GA Volatile vs intravenous Isoflurane vs Desflurane vs Sevoflurane Number of exposure to anesthesia

27. Type of Surgery Evered 2011- RCT, 644 participants

28. RA vs GA Mason 2010: systematic review with meta-analysis, 21 studies. Mandal 2011: RCT, 60 participants, GA vs EA.

29. Volatile vs Intravenous Chen 2014, retrospective, secondary analysis, 26,725 Taiwanese

30. Iso vs. Des vs. Sevo Ye 2013. Cell culture. Use of Iso , sevoflurane , and propofol Zhang 2012. Pilot study, 15 per group, Isoflurane , desflurane .

31. Reasons for Various Results Different neuropsychological tests Different design and methodology

32. Cognition in Aging Identify cognitive functions List age-related changes in cognitive functions Identify activities promoting healthy cognitive functions POCD vs POD Name precipitating variables of POCD Strategies minimizing POCD

33. Strategies Preoperative screening Hemodynamic monitoring- is 20% BP threshold is applicable for older adults? Monitor oxygenation and ventilation Temperature regulation Use of BIS monitor

34. References Mortimer JA, Snowdon DA, Markesberry WR. Head circumference, education, and risk of dementia: Findings from the Nun study. J Exp Psychol. 2003; 25(5): 671-679. Scarmeas N, Albert SM, Manly JJ, Stern Y. Eudcation and rates of cognitive decline in incident of Alzheimer’s disease. J Neurol Neurosurg Psychiatry. 2006; 77:308-316 Richards M, deary IJ. A life course approach to cognitive reserve: a model for cognitive aging and development. Annals of Neurol . 2005;58(4):617-622 Colcombe SJ, Erickson KI, Raz N, et al. Aerobic fitness reduces brain tissue loss in aging humans. J Gerontol A. 2003; 58(2): 176-180 Erickson KI Prakash RS, Voss MW, et al. Aerobic fitness associated with hippocampal volume in elderly humans. Hippocampus. 2009; 19(10): 1030-1039. N . A. Dennis and R. Cabeza , “Neuroimaging of healthy cognitive aging,” in Handbook of Aging and Cognition, F. I. M. Craik and T. A. Salthouse , Eds., pp. 1–54, Psychology Press, New York, NY, USA, 3rd edition, 2008 . Sullivan EV,    Pfefferbaum A ,   Adalsteinsson E,   Swan GE ,   Carmelli D. Differential rates of regional brain change in callosal and ventricular size: a 4-year longitudinal MRI study of elderly men. Cereb Cortex. 2002; 12(4): 438-45 Bigler ED, Blatter DD, Anderson CV, Johnson SC, Gale SD, Hopkins RO, Burnett B. Hippocampal volume in normal aging and traumatic brain injury. AJNR. 1997; 18: 11-23. Saczynski JS, Jonsdottir MK, Sigurdsson S, Eiriksdottir G, Jonsson PV, Garcia ME, et al. White matter lesions and cognitive performance: the role of cognitively complex leisure activity. J Gerontol A Biol Sci Med Sci. 2008; 63(8): 848-854. Gow AJ, Bastin ME, Phil D, Maniega SM, Hernandez V, Morris Z, Murray C, et al. Neuroprotective lifestyles and aging brain. Neurology. 2012;79(17): 1802-1808. Ybarra O, Burnstein E, Winkielman P, Keller M, Mannis M, Chan E, Rodriguez J. Mental exercising through simple socializing: social interactions promotes general cognitive functioning. Pers Soc Psychol Bull. 2008;34(2): 248-259. Xiao-dong Z. Mei- hua P, Yan- shu W, Chun-sheng F. Influence of sub-anesthetic dose of ketamine and dexmedetomidine on early postoperative cognitive dysfunction in elderly orthopedic patients under total intravenous anesthesia. Journal of Jilin University. 2013

35. Thank you!