Presentation on theme: "Clinical Implications of the Aging Physiology"— Presentation transcript:
1Clinical Implications of the Aging Physiology Anita Chopra, MDDirector, NJISAUMDNJ-SOM
2Clinical Implications of the Aging Physiology This Care of the Aging Medical Patient in the Emergency Room (CAMPER) presentation is offered by the Department of Emergency Medicine in coordination with the New Jersey Institute for Successful Aging.This lecture series is supported by an educational grant from the Donald W. Reynolds Foundation Aging and Quality of Life program.
3Learning Objectives Describe the concept of homeostenosis Review the physiological changes associated with age in various systems of the bodyDiscuss the significance of age associated physiologic changes on the clinical presentation and management of older patients
4An 82 year old female presents with increasing shortness of breath and fatigue for the last few days. She has a history of hypertension, diabetes mellitus type 2, and osteoarthritis of the knees. Her medications include glyburide 5 mg daily, hydrochlorothiazide 25 mg daily, lisinopril 10 mg daily, and Ibuprofen 200 mg once daily as needed. BP is 110/70, resp. 20/minute, pulse is irregular. Lungs reveal bibasilar crackles and there is trace pedal edema. PaO2 on room air is 65. EKG reveals
5Decline in renal function Hypoxia Which age-related physiologic change makes her more vulnerable to develop symptoms of CHF?Decline in renal functionHypoxiaIncrease in atrial natriuretic peptide (ANP) levelsIncrease in BPTachycardia and loss of atrial kickCorrect answer: E. Tachycardia and loss of atrial kick
6An 80 year old white male complains of mild shortness of breath on exertion. He denies any chest pain, wheezing, or cough. There is no history of hypertension or CAD. He denies a history of smoking. On examination, his lungs are clear with no crackles or wheezing. X-ray of the chest and electrocardiogram reveal normal findings. Patient is referred for pulmonary function testing.
7Which of the following describes expected age- related changes in pulmonary function? Decreased total lung capacity, decreased FEV1, decreased residual volumeIncreased total lung capacity, decreased FEV1 and decreased residual volumeIncreased total lung capacity, decreased FEV1 and increased residual volumeStable total lung capacity, decreased vital capacity, decreased residual volumeStable total lung capacity, decreased vital capacity, increased residual volumeCorrect answer: E. Stable total lung capacity, decreased vital capacity, increased residual volume.
8Which aspect of renal function is relatively maintained with aging ? Ability to excrete acid loadConcentrating capacityDiluting capacityErythropoietin productionMetabolism of parathyroid hormoneCorrect answer: D. Erythropoietin production.
9Aging Normal aging is not a disease Chronologic age & physiologic age are not the sameIndividuals “age” at different rates and there is significant variabilityIncreased susceptibility to diseases
10Spectrum Of Aging Aging, with disease and disability Usual aging, with the absence of overt pathology, but with some declines in functionSuccessful aging or healthy aging, with little or no pathology and little or no functional loss
11Aging and Disease“Homeostenosis”: Diminished ability to maintain homeostasis under stressDiseases can present atypically in old ageDisease in old age is usually modified (presentation, clinical course, response to treatment, outcomes) by interaction with age-related changesGeriatric Syndromes are the result of interaction of physiologic changes of aging, diseases and risk factors
12Aging and Physiologic Rhythms Attenuation of pulsatile secretion of hormones (e.g., melatonin, ACTH, TSH, LH/FSH, GH)Reduction in circadian amplitude of physiologic processesPlasma cortisolSleepBody temperatureLoss of complexity in physiologic functions may contribute to impaired response to stressors
13Age-related decline in heart rate variability could be due to: (1) dropout of sinus node cells, (2) altered ß-adrenergic receptor responsiveness, and (3) an apparent reduction in the parasympathetic tone
14Aging and Homeostatic Challenges Blood pressure regulationVolume regulationTemperature regulation
15An 80 year old male presents with complaints of dizziness, especially in the early afternoon. He reports that that he has "fainted" once, but was not seriously injured at this time. His medical history includes COPD, peripheral vascular disease, and hypertension. His hypertension is currently treated with hydrochlorothiazide 25mg QD and felodipine 5 mg QD.
16What age related changes are contributing to his dizziness/syncope? Decreases fluid volumeImpaired cerebral auto regulationOrthostatic hypotensionPostprandial hypotensionAll of the above
17Aging and Blood Pressure Regulation Baroreflex response to arterial pressure changes progressively decline with age, resulting in increased risk of orthostatic hypotensionReduced adrenergic responsiveness by the aged heart diminishes baroreflex-mediated cardioacceleration in response to hypotensionDecrease in cerebral blood flow by 20%Cerebral autoregulation process impaired in chronic hypertension
18Clinical Implications Postprandial hypotension: Decline in blood pressure after a meal is prevalent among older personsIncreased risk of orthostatic and postprandial hypotension with medications, e.g. nitrates, diuretics, antihypertensive medsOlder patients vulnerable to cerebral ischemia and syncope
19Aging and Volume Regulation Ms. K., 25 years oldFluid deprivation for 72 hours due to sore throat (strep plus mononucleosis)Sodium: No changeBUN: No changeSerum Creatinine: No changeMild hypotension with sinus tachycardia of 130Mrs. L., 80 years oldFluid deprivation for 24 hours(made NPO by an intern, no IV fluids ordered)Sodium: 146 – 150BUN:Serum Creatinine: No changeCardio-vascular changes: hypotension with sinus tachycardia of 100
20Which of the following statements about age-related changes in sodium and water homeostasis is not true?There is impaired conservation of Na and waterHypernatremia may occur without clinical signs of dehydrationAtrial natriuretic peptide (ANP) levels are decreasedThere is decrease in renal response to ANP
21Clinical Implications Predisposition to DehydrationDecrease in total body water as a percentage of body weightDecreased thirst driveDecreased antidiuretic hormone (ADH) response to hypovolemiaDecreased maximum urinary concentrationImpaired access to water due to physical or cognitive disordersHyponatremia & CHFDecreased ability to excrete free water load leading to hyponatremia and fluid overload
22Aging and Thermoregulation Basal heat production decreases by 20% from age 30 years to age 70 years due to active muscle lossWith age, the ability to regulate body temperature and to adapt to different thermal environments declinesElderly are more prone to hyper- and hypothermia
23Mrs. S is an 88-year-old woman who lives alone Mrs. S is an 88-year-old woman who lives alone. She has history of osteoarthritis of her hips and knees. One night while going to the bathroom, she fell. Unable to get up or call for help, Mrs. S lay on the bathroom floor until her daughter found her the next day and called an ambulance to bring her to the ER. She does not complain of pain. On examination, she is lethargic and somewhat confused. Her skin is cold and pale. BP is 110/60, pulse 60/min., rectal temp 95 F. X-rays reveal no fracture.
24What age-related changes make her more vulnerable to develop hypothermia? Decreased production of thyroid hormoneImpaired blood redistribution from splanchnic circulationImpaired skin vasodilation responseReduced muscle activity and less shiveringDecrease in basal metabolic rate
25Hypothermia: Risk Factors Reduced muscle activity and less shiveringImpaired vasoconstrictor response to cooling by skin arterioles, which results in impaired ability to conserve heatReduced meal-induced thermogenesisDelayed perception of being coldDifficulty in discriminating temperature differences
26An 80 year old female is found unresponsive in her apartment on a hot summer day. The apartment does not have air-conditioning. She has history of mild dementia, CHF, and Parkinson’s disease. Her medications include enalapril, furosemide, and levodopa/carbidopa. In the emergency room, her BP is 85/50, pulse 100/min, and rectal temp is 105 F. Her skin is hot and dry.
27What age-related changes predispose an elderly person to heat stroke and its consequences? Reduced muscle activityIncreased threshold to initiate sweatingImpaired vasoconstrictor responseImpaired ability to conserve heatIncreased output of eccrine sweat glands
28Hyperthermia: Risk Factors Impaired skin vasodilatation response and impaired blood flow redistribution from splanchnic and renal circulationsDecreased thirstIncreased threshold temperature to initiate sweatingDecreased output of eccrine sweat glandsDrugs that impair the response to heat (such as anticholinergic agents [hypohydrosis], diuretics [hypovolemia], and ß-blockers [impaired cardiovascular responsiveness]) increase the risk of heat stroke
29Fever Response In The Elderly The ability to raise body temperature (generate fever response) in response to pyrogens (bacterial endotoxins) is blunted with ageUp to 25% of older persons with sepsis do not exhibit a febrile reactionAnother definition of fever is a temperature increase of > 2°F (1.1°C) over baseline (if a baseline temperature is available)This definition has a sensitivity of 82.5% and specificity of 89.9% in the institutionalized older population
30Which of the following is not true about age-related cardiac changes? Resting cardiac output unchangedEjection fraction reducedEarly diastolic filling reducedEnd diastolic filling increased
31Cardiovascular: Structure Age-associated changeConsequence↓ compliance of arterial tree↑ after load on left ventricle and LVH↑ Systolic and pulse pressureMyocardial cell hypertrophy, ↑ interstitial fibrosis, drop out of cardiac myocytesSlowing of ventricular relaxation, ↓ LV compliance, ↑ contribution of atrial contraction to LV end diastolic volumeApoptosis of S-A pacemaker cells, fibrosis and loss of his bundle cellsSlower intrinsic heart rate, varying degrees of heart block
32Cardiovascular: Structure (cont’d) Age-associated changeConsequenceDecreased responsiveness to beta adrenergic stimulation and reactivity to baroreceptors and chemoreceptors↑ circulating catecholaminesFibrosis and calcification of heart valvesAortic valve sclerosis and stenosis
33Image used by permission of Merck & Co., Inc. Source: The Merck Manual of Geriatrics, 3rd Edition, edited by Mark H. Beers, and Robert Berkow. Copyright 2000 by Merck & Co., Inc., Whitehouse Station, NJ.The early diastolic left ventricular filling rate progressively slows after age 20, so that by age 80, the rate is reduced by up to 50%
34Cardiovascular Physiology ↓ maximal heart rate↓ maximal cardiac output at exercise↓ maximal aerobic capacity↓ cardiovascular reserve↓ threshold for congestive heart failure and atrial fibrillation
35Clinical Implications Systolic HTN and widened pulse pressure are risk factors for stroke, renal failure, and heart diseaseAge is the strongest predictor of mortality following Acute MIDiagnosis more difficult due to atypical presentationDiastolic heart failure (EF ≥ 50%) accounts for as many as 50% of CHF patients over age 65Atrial fibrillation becomes more of a physiologic burden to the old heart because of age-related slowing of diastolic filling due to LV stiffness and greater dependence for adequate filling on atrial contraction
36An 82 year old female presents with increasing shortness of breath and fatigue for the last few days. She has a history of hypertension, diabetes mellitus type 2, and osteoarthritis of the knees. Her medications include glyburide 5 mg daily, hydrochlorothiazide 25 mg daily, lisinopril 10 mg daily, and Ibuprofen 200 mg once daily as needed. BP is 110/70, resp. 20/minute, pulse is irregular. Lungs reveal bibasilar crackles and there is trace pedal edema. PaO2 on room air is 65. EKG reveals
37Decline in renal function Hypoxia Which age-related physiologic change makes her more vulnerable to develop symptoms of CHF?Decline in renal functionHypoxiaIncrease in atrial natriuretic peptide (ANP) levelsIncrease in BPTachycardia and loss of atrial kickCorrect answer: E. Tachycardia and loss of atrial kick
38Aging Respiratory System Calcification of bronchial and costal cartilageStiffness of chest wallsWork of breathingEnlargement of alveolar ductsAlveolar surface areaDecreased lung elasticity and elastic recoilLower respiratory muscle strength and enduranceDecrease in cough and mucociliary clearance
39Effects of Aging on Lung Function Lower maximum expiratory flows: FEV1, FEV1/FEV loss of approximately 15-30cc/year in FEV1 from the peak achieved at age yearsIncreased FRC and RV, lower VC, but stable TLCPaO2 declines linearly with aging until age 75, at which time it stabilizes at about 80 mm Hg in healthy nonsmokers.This gradual decline is mostly attributable to V/Q mismatch caused by age-related collapse of peripheral airways, leading to shunting of blood through nonventilated alveoli. PaO2 at any age can be roughly estimated by the equation PaO2 = (0.3 x age)
40Effects of Aging on Lung Function Lower diffusing capacityReduced respiratory drive for hypoxia and hypercarbia
41Clinical Implications Higher risk for developing respiratory failure in response to an acute illnessNon-pulmonary conditions such as congestive heart failure, cerebrovascular accidents, and nutritional disorders can also precipitate respiratory failure in the elderlyThe complaint of dyspnea must be taken seriously because, compared with younger adults, older adults may not develop this symptom until they are at a later stage in their illnessThe elderly have a 5-10 fold increased risk of pneumonia as compared to younger adults and are much more likely to die from this disease than their younger counterparts
42An 80 year old white male complains of mild shortness of breath on exertion. He denies any chest pain, wheezing, or cough. There is no history of hypertension or CAD. He denies a history of smoking. On examination, his lungs are clear with no crackles or wheezing. X-ray of the chest and electrocardiogram reveal normal findings. Patient is referred for pulmonary function testing.
43Which of the following describes expected age- related changes in pulmonary function? Decreased total lung capacity, decreased FEV1, decreased residual volumeIncreased total lung capacity, decreased FEV1 and decreased residual volumeIncreased total lung capacity, decreased FEV1 and increased residual volumeStable total lung capacity, decreased vital capacity, decreased residual volumeStable total lung capacity, decreased vital capacity, increased residual volumeCorrect answer: E. Stable total lung capacity, decreased vital capacity, increased residual volume.
44Renal SystemGeneral decline in glomerular filtration rate by about 1 ml/year after 4030% showed no deterioration (BLSA)Progressive decline in ability to excrete a concentrated or a dilute urineDelayed or slowed response to sodium deprivation or a sodium loadDecreased levels of renin and aldosteroneIncreased dependence on renal prostaglandins to maintain perfusionDecreased Vitamin D activationLindeman RD, Tobin J, Shock NW. J Am Geriatr Soc 1985;33(4):
45Clinical Implications Creatinine clearance should always be calculated before starting or increasing doses of a medication cleared by the kidneySerum creatinine values are not reliable estimates of renal functionNephrotoxic drugs should be avoided whenever possibleUse of drugs that inhibit the renin-angiotensin-aldosterone system (such as ACE inhibitors and angiotensin and aldosterone receptor antagonists) can contribute to hyperkalemia in older adults.Acute renal failure develops faster, with relatively minor stressors, and carries a higher mortality
46Calculating Creatinine Clearance Estimate by Cockcroft - Gault formulaMDRD ( modification of diet in renal disease)(140 - age [yr]) x weight [kg]x 0.85 (if patient is female)72 x serum cr (mg/dL)170 x [Scr] x [age] x [0.762 if patient is female; if patient is black] x [SUN] x [albumin]+0.318
47Which aspect of renal function is relatively maintained with aging ? Ability to excrete acid loadConcentrating capacityDiluting capacityErythropoietin productionMetabolism of parathyroid hormoneCorrect answer: D. Erythropoietin production.
48Mrs. S is a 70 year old retired school teacher, who comes for a routine follow-up of her blood pressure. During her visit, she comments that she is concerned about her memory. She notes that she's having more difficulty remembering the names of individuals she knows when she meets them. She also complains of misplacing her keys .
49Which of the following is least consistent with normal aging? Delayed retrievalDecreased speed of processingForgetfulness that interferes with independent livingDecreased multitasking performance
50Aging Nervous System Memory Immediate memory (sensory) No changeShort term memoryIt is widely believed that one type of memory, called working memory, is most affected by age. Working memory is the retention of information that must be manipulated or transformed in some way.Long-term memoryLate in the aging process, “semantic memory” declines, referring to memories of facts or concepts. “Procedural memory” remains unaffected.
51Aging Nervous System Intellect Processing speed Crystallized intelligence (learning and experience stable or improves with age)Fluid intelligence (problem-solving with novel material requiring complex relations) declines rapidly after adolescenceProcessing speedMental processing and reaction time become slower with age
52Aging Nervous System Language Attention Executive function Vocabulary - increases into 50s and 60s - errors or failures in naming occur with increasing frequency, beginning in mid-life; encoding strategies very helpfulSyntactic skills - combine words in meaningful sequence - no decline with ageAttentionNo changeExecutive functionAbility to conceptualize, plan does not change
53Age Associated Memory Impairment (AAMI) Decreased multitasking performanceDecreased processing speedImpaired or delayed retrievalClinical manifestationsRetrieving the name of a vague acquaintanceRemembering every item to buy from a grocery store without a listRecalling where an object was placed
54Vision and Hearing Vision Hearing Decline in accommodation (presbyopia), low-contrast acuity, glare tolerance, adaptation, and color discrimination. These changes affect reading, balance, and driving.HearingHigh frequency sensory neural hearing loss (presbycussis). Consequences include difficulty in localizing sound and understanding speech.
55Improving Communication Provide a respectful and supportive environmentAllow sufficient time for the older patient to process new information.Speak slowly facing the patient. Do not speak louderProvide written materials to complement oral instructions.Use repetition to ensure that instructions were clear and that your communication has been effective.
56Laboratory Values In Old Age UNCHANGEDDECREASEDINCREASEDLiver function testsSerum albuminAlkaline phosphataseCoagulation testsCreatinine clearanceSed rateArterial blood GasespaO2pHPost-prandial blood sugarpCO2Total cholesterolSerum electrolytesSerum creatinineTriglyceridesCalcium, phosphorusTotal proteinT4, TSHComplete Blood Count
57Contribution of Hospitalization Interaction of Aging and HospitalizationAge-Related ChangesContribution of HospitalizationEffectsConsequencesLoss of muscle mass and strengthBed rest, restraints, tethersDeconditioningDependency, fallsBaroreceptor insensitivity, less thirst drive, less body waterInaccessibility to fluids, disease-associated dehydrationPostural hypotensionFalls & related injuries, dizziness, syncopeLower maximum expiratory flows, reduced paO2Reduced ventilation from bed restHypoxia, respiratory failureDelirium, increased mortality from pneumoniaReduced bladder capacity, prostate enlargement, pelvic floor relaxationBarriers, unfamiliar environmentTendency to incontinenceFunctional incontinence, cathetersFragile skinReduction in vascularityBed rest, shearing, incontinenceIncreased pressure on buttocks, healsPressure soresVision & hearing lossSensory deprivation (e.g., glasses, hearing aid)Sensory overstimulation (e.g., sleep deprivation, noisy environment)ConfusionDeliriumRestraintsLonger length of stayPsychotropic drugsModified from: Creditor MC. Hazards of hospitalization of the elderly. Ann Int Med 1993;118(3):
58ConclusionsAging is associated with reduced functional reserve and a compromised ability to cope with stressorsElderly are a heterogeneous group and there is great individual variabilityAlways think of interventions which may be useful in helping patients cope with and/or overcome some of the changes brought by normal agingStart building your reserves NOW