Lecture 16 - Linking Minor Illness with Major Disease

factors that influence illness

aging, genetics, lifestyle, work, behaviour and peer influences

Ageing

• not a disease

• occurs at different rates among individuals

• does not generally cause symptoms

• influenced by genetics, lifestyle, physiology and socioeconomic factors

key characteristics of ageing

• cellular and physiological deterioation

• increased vulnerability to disease

• reduced ability to adapt to stress

• impaired homeostasis

Multimorbidity

having multiple long term health conditions is common in older people. most people over 65 have at least 2 and most over 75 have at least 3

arteries structural changes and functional changes

structural

• thickening of the muscular layer

• increased collagen deposition, making arteries less elastic

• endothelial dysfunction, reducing vasodilation

• increased vascular stiffness

functional

• increased systolic blood pressure

• baroreceptor reflex declines

• increased risk of fainting and postural tension - affect approx 30-50% if people over 75 years

heart structural and functional changes

structural

• loss of sa node and bundle of his cells

• thickening of the heart wall

• increased collagen and enlargement of myocardial cells

functional

• decrease in maximal heart rate achievable

• decrease in cardiac output

• beta receptors downregulated

afterload

the resistance the heart must overcome to pump blood, increased arterial stiffness increases after load

why do arteries become stiffer

collagen deposition, increased fibronectin and cross linking (AGES), fragmentation of elastin and calcium deposition

age associated changes of cardiovascular physiology

• maintenance of resting left ventricular function

• decreased ability to compensate for stress or impaired LV function

• blunted heart rate response to exercise requires a compensatory increase in stroke volume to increase cardiac output

age related changes in respiratory system

structural

• rigidity of ribs, loss of respiratory muscle strength

• loss of lung elasticity

• reduction in number of airway cilia

• reduction in alveolar surface area

functional

• FEV1 decreases

• cough reflex decreases

• blood po2 declines

factors that influence illness minor → major lifestyle

• smoking and alcohol consumption among children

• nutrition among children

• physical activity among children

• overweight and obesity among children

• supply of fruit and vegetables for consumption

• tobacco consumption among adults

• alcohol consumption among adults

• overweight an obesity among adults

types of diabetes

type 1 - pancreatic cells produce little to no insulin

type 2 - body cells become resistant to insulin, particularly fat, liver and muscle cells

gestational - diabetes that develops during pregnancy

type 2 diabetes

• accounts for approx 85-90% of diabetes cases

• strongly associated with lifestyle and obesity

• develops when insulin resistance prevents normal glucose uptake by cells

common symptoms of type 2 diabetes

• polyuria - frequent urination

• polydipsia - excessive thirst

• polyphagia - increased hunger

• fatigue

• blurred vision

• slow healing infectionse

metabolic syndrome

insulin resistance syndrome - a group of risk factors that occur together and increase the risk of coronary artery disease, stroke and type 2 diabetes

risk factors of diabetes

• increased blood pressure

• raised fasting blood glucose

• increased waist circumference

• raised triglycerides

obesity, physical activity and diabetes risk

• obesity increases the risk of developing type 2 diabetes

• higher bmi associated with increased diabetes risk

• lower levels of physical activity are associated with increased diabetes risk

what are some lifestyle interventions to help treat diabetes

weight loss and exercise can help reduce the risk of developing diabetes in people with impaired glucose tolerance