Homeostasis in Aging PDF

Homeostasis in Aging Clinical Sciences IV Geriatrics Paul B. Volker, MD, FAAFP Assistant Professor Department of Osteopathic Clinical Medicine 1 April 2024 1 April 2024 2 Outline Homeostasis Homeostenosis Normal aging in organ systems Strategies for successful aging 1 April 2024 Volker Homeostasis 3...

Homeostasis in Aging Clinical Sciences IV Geriatrics Paul B. Volker, MD, FAAFP Assistant Professor Department of Osteopathic Clinical Medicine 1 April 2024 1 April 2024 2 Outline Homeostasis Homeostenosis Normal aging in organ systems Strategies for successful aging 1 April 2024 Volker Homeostasis 3 Objectives Understand, give examples and apply the concepts of homeostasis and homeostenosis in the process of aging and disease Explain the causes and effects of normal aging by organ system Understand, recommend, and incorporate (you, future physicians!) lifestyle attitudes and modifications which promote healthy aging 1 April 2024 Volker Homeostasis 4 Patterns of Death 1 April 2024 Volker Homeostasis 5 The tendency toward a stable equilibrium between interdependent elements, especially as maintained by physiological processes HOMEOSTASIS 1 April 2024 Volker Homeostasis 6 Homeostasis Altered Homeostasis in Geriatrics refers to the process of change brought on by the normal aging process and its effect on illness and injury. As we study the aging process, it is very important for clinicians to understand what changes are normal in the aging process, what changes are brought about because of disease or disuse, and how these two processes interact to produce risk, morbidity and loss of function, and mortality. 1 April 2024 Volker Homeostasis 7 Homeostasis in Aging Physiologic reserves are diminished in each individual body system Diminished feedback systems Loss of integrated physiologic homeostasis Leading to diminished total-body reserves Crisis in one system induces loss of regulation in others This is an interrelated, interdependent problem 1 April 2024 Volker Homeostasis 8 HOMEOSTENOSIS 1 April 2024 Volker Homeostasis 9 Homeostasis Norm al age -relat ed de cline Crisis Crisis 1 April 2024 Volker Homeostasis 10 Homeostenosis Norm al age -relat ed de cline Crisis Physiologic Reserve or Resilience Crisis ases e r c n I t i Defic e v r e s e gic R o l o i s y h P 1 April 2024 Volker Homeostasis Death 11 Homeostenosis As we age we have less reserve As we age sudden illness results in crisis and recovery does not usually return to baseline Result: mild/moderate illness & injury → prolonged recovery (loss of function) Serious illness & injury → significantly increased risk of death 1 April 2024 Volker Homeostasis 12 Today we will… Try to differentiate between normal aging and pathologic aging Focus on normal changes in the geriatric patient due to aging Explore abnormal responses to aging by organ system 1 April 2024 Volker Homeostasis 13 Principles Homeostatic balance will be less optimal, and reached more slowly, with age Decreased cellular function (rate and efficiency) secondary to accumulation of lipofuscin, secondary lysosomes and other inter- and intracellular detritus (clinker theory) Drug distribution and homeostatic mechanisms change with change in body composition, particularly a decrease in total body water 1 April 2024 Volker Homeostasis 14 Your Case 89 y/o man brought to your ED from local Nursing Home with confusion over the past 12-24 hrs. PMHx: DM-2, CAD, HTN, 50 p/y smoking hx, DJD, “forgetfulness” SHx: Retired university professor, no immediate family Meds: >25 1 April 2024 Volker Homeostasis 15 Your Case VS: T99.5°F, P92, R20, BP 118/60, SaO2.90 Obtunded MM dry Lungs: shallow resps CV: no M, G Abd scaphoid, soft without masses, NABS Ext: no edema, distal pulses intact Neuro: MAE 1 April 2024 Volker Homeostasis 16 Your Case DDx:? 1 April 2024 Volker Homeostasis 17 AGING IN ORGAN SYSTEMS 1 April 2024 Volker Homeostasis 18 Organ systems to consider CNS/Neuro Endocrine Metabolic Cardiovascular Pulmonary GI 1 April 2024 GU Musculoskeletal Integumentary Special senses Psychiatric/psychologic Infectious Volker Homeostasis 19 Central Nervous System Aging Physiology Clinical Presentation Cerebral atrophy Decreased blood flow Decreased myelin and total brain lipid Altered neurotransmitter concentration (dopamine and serotonin) Increased delicacy of epidural vessels Brain shrinkage (involution) Slowed mentation More difficulty in forming new memories Mood, circadian, and concentration changes Increased risk of intracranial bleeding to minimal trauma 1 April 2024 Volker Homeostasis 20 Endocrine System Aging Physiology Decreased T3 Gradual pancreatic b-cell senescence and increased tissue resistance to insulin Marked decrease in DHEA Sex hormone decrease 1 April 2024 Clinical Presentation Occult hypothyroidism Increased fasting glucose and glucose intolerance Osteoporosis, decreased libido, decreased corticosteroid reserve Volker Homeostasis 21 Endocrine System Aging Physiology Decreased plasma renin and aldosterone Increased norepinephrine, vasopressin, atrial natriuretic peptide, and parathormone Decreased responsiveness to b-adrenergic stimulation 1 April 2024 Clinical Presentation Predisposition to hyperkalemia Impaired extracellular volume regulation and electrolyte homeostasis Normal resting heart rate but diminished maximal heart rate Volker Homeostasis 22 Cardiovascular System Aging Physiology Decreased baroreceptor response Increased collagen deposition and cross-linking → increased arterial stiffness Decreased cardiocytes and increased fibroblasts 1 April 2024 Clinical Presentation Increased risk of orthostatic hypotension (falls) Increased SBP (stiff pipes) and afterload Impaired LV relaxation (diastolic dysfunction) Increased reliance on atrial kick (lacking in Afib) Volker Homeostasis 23 Cardiovascular System Aging Physiology Marked dropout of pacemaker cells in SA node Deterioration of conductive cells in SA/AV/His/Purkinje system 1 April 2024 Clinical Presentation Increased risk of atrial fibrillation Decreased maximal heart rate Increased risk of heart block Volker Homeostasis 24 Pulmonary System Aging Physiology Increased collagen deposition and cross-linking → increased arterial stiffness; fibrosis Accumulated effects of oxidative stress/free radical damage Reduced diaphragmatic strength (sarcopenia) 1 April 2024 Clinical Presentation Decreased lung elasticity, decreased FVC and FEV1 Loss of alveoli and total alveolar surface area, and thus maximal oxygen uptake (emphysematous change) Reduced tidal volume, V/Q mismatch Volker Homeostasis 25 Gastrointestinal System Aging Physiology Dental caries Slowed colonic transit time Increased hepatocyte accumulation of lipofuscin and secondary lysosomes 1 April 2024 Clinical Presentation Decreased appetite, infection, ?CVD Constipation Reduced metabolism, clearance of drugs Volker Homeostasis 26 Renal/urinary System Aging Physiology Decreased renal mass, GFR, renal tubular secretion and concentrating ability, and bladder capacity Gradual hypertrophy of prostate 2° to lifelong testosterone exposure 1 April 2024 Clinical Presentation Decreased creatinine clearance (~8% per decade) Decreased drug clearance Obstruction due to BPH Carcinoma of Prostate risk Volker Homeostasis 27 Musculoskeletal System Aging Physiology Mechanical wear and tear of articular cartilage Gradual lengthening of tendons, ligaments, and fascia 1 April 2024 Clinical Presentation Arthritic pain, loss of ROM and stability Increased laxity of joints Flattening of arch of feet Why aren’t we all walking around on pancake feet? Volker Homeostasis 28 Musculoskeletal System Aging Physiology Decreased muscle mass and lean body mass Negative calcium balance in both sexes, decreased bone mass 1 April 2024 Clinical Presentation Sarcopenia, weakness, increased fall risk Osteoporosis, loss of height, increased curvature of spine (kyphosis), decreased muscle strength for breathing, and gait impairment Volker Homeostasis 29 Skin Aging Physiology Decreased vascularity of dermis, decreased total body water Crosslinking and deterioration of collagen and elastin Altered epidermal turnover time Decreased melanocytes Low dermis density, reduced subcutaneous adipose and eccrine function Hair loss 1 April 2024 Clinical Presentation Dry skin, greater risk of tearing and injury Prolonged wound healing Uneven tanning Poor insulation, decreased sweating response Decreased self-esteem Volker Homeostasis 30 Skin Tear Shearing tear along dermis/epidermis plane 1 April 2024 Volker Homeostasis 31 Special Senses—Vision Aging Physiology Clinical Presentation Increased rigidity of iris Decreased size of anterior chamber Accumulation of yellow substance in lens Decreased elasticity and cloudiness of lens (cataracts) Decreased size of pupils, impaired adaptation to variable lighting Alteration of color perception; e.g. blue appears green-blue Significant impairment of vision in presence of glare and lowlight conditions; falls; global impairment 1 April 2024 Volker Homeostasis 32 Special Senses—Hearing Aging Physiology Loss of cochlear neurons Hearing loss for pure tones; higher frequencies more than lower frequencies 1 April 2024 Clinical Presentation Social isolation, impaired ability to learn and to keep up Volker Homeostasis 33 Special Senses—Olfactory Aging Physiology Detection reduced by 50% 1 April 2024 Clinical Presentation Reduced appetite Decreased protein/calorie intake Volker Homeostasis 34 Immune System Aging Physiology Involution of thymus with decreased new T lymphocytes, decreased capability of T lymphocytes to proliferate in response to antigens Decreased suppressor T lymphocytes, decreased humoral immunity 1 April 2024 Clinical Presentation Anergy (loss of response) to various skin tests Inadequate response to extrinsic antigens like the pneumococcal vaccine. Decreased T cell function Decreased antibody response Volker Homeostasis 35 Spiritual/Psychological Systems Aging Physiology Clinical Presentation Decreased special senses Loss of spouse and loved ones/close friends Dependency and debility Frailty Barriers to communication Grief, sense of loss, depression; social isolation Shame, loss of selfesteem and selfconfidence; despair 1 April 2024 Volker Homeostasis 36 In General Aging Physiology Lifelong accumulation of trauma Environmental exposures Non-medical stressors – – – – Social Societal Cultural Financial 1 April 2024 Clinical Presentation Various disabilities Carcinogenesis Diseases of poverty, abuse, exploitation, discrimination Volker Homeostasis 37 Your Case 89 y/o man brought to your ED from local Nursing Home with confusion over the past 12-24 hrs. PMHx: DM-2, CAD, HTN, 50 p/y smoking hx, DJD, “forgetfulness” SHx: Retired university professor, no immediate family Meds: >25 VS: T99.5°F, P92, R20, BP 118/60, SaO2.90 Obtunded MM dry Lungs: shallow resps CV: no M, G Abd scaphoid, soft without masses, NABS Ext: no edema, distal pulses intact Neuro: MAE 1 April 2024 Volker Homeostasis 38 Organ systems to consider CNS Endocrine Metabolic Cardiovascular Pulmonary GI 1 April 2024 GU Musculoskeletal Integumentary Special senses Psychiatric/ psychologic Infectious Volker Homeostasis 39 Your Case 89 y/o AAM brought to your ED from local Nursing Home with confusion over the past 12-24 hrs. PMHx: DM-2, CAD, HTN, 50 p/y smoking hx, DJD, “forgetfulness” SHx: Retired university professor, no immediate family Meds: >25 VS: T99.5°F, P92, R20, BP 118/60, SaO2.90 Obtunded MM dry Lungs: shallow resps CV: no M, G Abd scaphoid, soft without masses, NABS Ext: no edema, distal pulses intact Neuro: MAE 1 April 2024 Volker Homeostasis 40 Obtundation: Differential Dx Hyponatremia Dehydration Hypoxia MI Addisonian crisis Hyperglycemia Urinary retention Constipation 1 April 2024 Volker Homeostasis Stroke Pneumonia Urosepsis Other infection Renal failure / azotemia Intoxication Depression 41 Summary Awareness of altered homeostasis can guide the provider To recognize more efficiently the disease states more commonly found in the geriatrics age group because of that altered homeostasis To consider multimorbidity in the evaluation and treatment in the geriatric population To treatments and interventions which are less likely to stress reserves To promote lifestyle changes which minimize further risk to homeostasis and crisis states 1 April 2024 Volker Homeostasis 42 Homeostenosis Norm al age -relat ed de cline Crisis Physiologic Reserve or Resilience Crisis ases e r c n I t i Defic e v r e s e gic R o l o i s y h P 1 April 2024 Volker Homeostasis Death 43 Take home All organ systems and tissues are affected by normal aging These changes generally result in decreased resilience to insult or change Decreased resilience (reserves) means decreased success of recovery from acute injury, physiologic and emotional stress, crisis 1 April 2024 Volker Homeostasis 44 Disclosures None But you still need to call home. 1 April 2024 Volker Homeostasis 45 Resources Fillit, Howard, Brocklehurst’s Textbook of Geriatric Medicine and Gerontology, 7th Ed. 2010. Fried, L.P., et. al. Frailty in Older Adults: Evidence for a Phenotype, Journal of Gerontology Geriatrics Review Syllabus (GRS): A Core Curriculum in Geriatric Medicine, 9th Ed., American Geriatrics Society, 2016. Halter, Jeffrey [et al.], Hazzard’s Geriatric Medicine and Gerontology, 6th Ed., McGraw-Hill, 2009. Ham, Richard J. and Sloane, Philip D., Ham’s Primary Care Geriatrics – A Case-Based Approach, 6th Ed., W.B. Saunders, 2014.* Kane, Robert L., et al. Essentials of Clinical Geriatrics, 7th Ed., McGraw-Hill, 2013. Medicare Payment Advisory Commission, MedPAC Data Book: Health Care Spending and the Medicare Program, 2015. Reuben, David B., et al. Geriatrics at Your Fingertips 2015, 17th Ed., American Geriatrics Society, 2015. Williams, B., et. al., Lange series, Current Geriatric Diagnosis & Treatment, 2nd Ed., McGraw-Hill, 2014. 1 April 2024 Volker Homeostasis 46