Lecture_W10_Diabetes and metabolic diseases-1.pdf

Diabetes and metabolic syndrome Brooke Coombes [email protected] Learning outcome • Describe the pathophysiology and presentation of diabetes and metabolic syndrome and their complications • Recognise symptoms of hypoglycaemia & hyperglycaemia • Describe the common macro/microvascular comp...

Diabetes and metabolic syndrome Brooke Coombes [email protected] Learning outcome • Describe the pathophysiology and presentation of diabetes and metabolic syndrome and their complications • Recognise symptoms of hypoglycaemia & hyperglycaemia • Describe the common macro/microvascular complications of diabetes • Discuss the management of diabetes and role of physiotherapy Prevalence in Australia ABS (Australian Bureau of Statistics) 2018. National Health Survey: First Results, 2017–18. ABS cat. no. 4364.0.55.001. Canberra: ABS. Impact • Diabetes is associated with many complications • 2-4 times more likely to develop heart disease or stroke • Hypertension, retinopathy, neuropathy, kidney disease • Life expectancy reduced by 8.2 and 7.5 years in men and women, respectively, when T2DM is diagnosed at the age of 50 years • Financial & economic consequences Definition • Diabetes is a group of metabolic diseases characterized by • Hyperglycaemia resulting from defects in insulin secretion, insulin action, or both • Long term damage, dysfunction and organ failure associated the chronic hyperglycaemia, especially Glucose (sugar) • Main source of energy for cells that make up brain, muscle, fat and other tissues • Brain requires a continuous supply of glucose – hence blood glucose is tightly regulated • Glucose comes from 2 major sources – food & liver • Liver stores and makes glucose Insulin • Insulin regulates how much glucose is in the blood • Insulin enables glucose to enter cells Glucose regulation • Insulin is a hormone that is secreted from pancreatic β cells • Glucagon is secreted by pancreatic alpha cells • Insulin & glucagon have opposite action Glucose regulation • After eating, glucose is absorbed into the bloodstream • Glucose in the blood triggers the pancreas to secrete insulin • Insulin enables glucose to enters cells • Liver stores glucose (as glycogen) àblood glucose drops à pancreas releases less insulin Glucose regulation • When glucose levels are low (e.g. haven’t eaten in a while): • Liver breaks down stored glycogen into glucose à keeps glucose level within a normal range Glucose regulation • In Type 1 Diabetes, the immune system destroys Beta cells in pancreas à body secretes little to no insulin à acute hyperglycaemia Glucose regulation • In Type 2 Diabetes, glucose isn’t taken up by cells (they are resistant to the action of insulin) • This stimulates the pancreas (Beta cells) to release more insulin à hyper-insulinaemia • Eventually the Beta cells become impaired and can’t make enough insulin to meet the body’s demands (insulin secretion problem) à hyperglycaemia 2 1 Glucose dysregulation in diabetes • Hyperinsulinaemia is seen early • Hyperglycaemia tends to develop slowly over months or years • Over time, treatment requirements escalate • Diabetes is a chronic progressive disease Davidson’s Principles and Practice of Medicine 23rd Ed Classification • 4 classes of diabetes • Additional related conditions/terms • Type 1 Diabetes • Pre-diabetes (high risk of diabetes) • Type 2 Diabetes • Metabolic syndrome • Gestational Diabetes (GDM) • Other Type 1 Diabetes (T1D) - Terminology • Formerly called: • Insulin-dependent Diabetes Mellitus • Juvenile Onset Diabetes Type 1 Diabetes (T1D) - Pathophysiology • Insulin secretion deficiency • Autoimmune disease involving destruction of β-cells à pancreas does not produce enough insulin • Genetic and/or environmental factors (eg viruses) • May have associated autoimmune disorders including thyroid disease, coeliac disease Type 1 Diabetes (T1D) - Presentation • Hyperglycaemic symptoms (thirst, polyuria, nocturia, fatigue), infections & weight loss • +/- Symptoms of ketoacidosis (rapid breathing, flushed cheeks, abdominal pain, sweet acetone smell, vomiting, dehydration hypotension, tachycardia, hypothermia, drowsiness)= medical emergency • Most cases detected soon after symptoms develop • Most common onset 5-7 years, but can onset in adults Type 2 Diabetes (T2D) - Terminology • Formerly called: • Adult Onset Diabetes • Non-insulin dependent Diabetes Mellitus (NIDDM) Type 2 Diabetes (T2D) – Pathophysiology • Insulin resistance (with or without insulin secretory defect) • 2 interrelated problems • Cells respond poorly to insulin and take in less sugar • Over time the pancreas doesn’t produce enough insulin Type 2 Diabetes (T2D) – Risk factors • Caused by genetic, environmental and lifestyle factors • Obesity • Inactivity • Family history • Ethnicity • Age • Prediabetes • Polycystic ovary syndrome Type 2 Diabetes (T2D) – Risk factors • • • Overweight or obese • Risk of T2D increases 10-fold in people with BMI > 30kg/m2 Fat distribution – storing fat around waist rather than hips • Risk of T2D rises if waist circumference > 101cm (men) or 89cm (women) Blood lipids – Risk of T2D increases if low HDL cholesterol and high triglycerides • Inactivity • Physical activity helps control your weight (uses glucose) • Physical activity makes your cells more sensitive to insulin • Ethnicity –Black, Hispanic, Native American, Asian and Pacific islanders > White people ↑ risk of T2DM according to BMI: Slide sourced from ADA Type 2 Diabetes (T2D) - Presentation • Symptoms develop slowly (can be present for years before Dx) • Hyperglycaemic symptoms (thirst, polyuria, nocturia, fatigue), infections & weight loss • Often not diagnosed until complications appear • e.g. numbness or tingling in hands/feet • Many cases undiagnosed Gestational Diabetes • Diagnosed during pregnancy in otherwise ‘non-diabetic’ women • Characterised by insulin resistance • Hormones block insulin action • Typically presents between 24th-28th week of pregnancy • Usually resolves after delivery • Increased risk of T2D developing later Pre-diabetes • Pre-diabetes is a condition in which blood glucose is higher than normal, but not high enough to be classified as diabetes • If left untreated, pre-diabetes often progresses to T2D Metabolic syndrome • Cluster of the most dangerous cardiovascular risk factors: • Diabetes or pre-diabetes • Abdominal obesity • Dyslipidaemia • High BP Metabolic syndrome IDF =International Diabetes Federation Metabolic syndrome • 20-25% of world’s adult population have metabolic syndrome • Adults with metabolic syndrome are • 3 times likely to have a heart attack or stroke • 5 fold greater risk of developing T2D • The more components of the metabolic syndrome – the higher the cardiovascular mortality rate Diagnosis of diabetes The Royal College of Pathologists of Australasia criteria Investigations • Fasting plasma glucose (FPG) • Glycated haemaglobin (HbA1c) • Oral glucose tolerance test (OGTT) • Ketones • Continuous glucose monitoring (CGM) • Islet autoantibodies Investigations • Plasma glucose or blood glucose • Measure of ‘acute’ blood glucose control • Easy to measure, but day-day variation Investigations • Glycated haemaglobin (HbA1c) • Gold standard measure of glycaemic control • Reflects blood glucose control over last 2-3 months (life of the red blood cell) • Test every 3-6 months • HbA1c aim: <7% Investigations • Oral glucose tolerance test (OGTT) • Blood glucose measured after fasting and then again 2hrs after drinking a standardized glucose rich drink Investigations • Ketones • People with T1D measure ketones (in urine or blood) if hyperglycaemia is suspected Investigations • Continuous glucose monitoring (CGM) Investigations • Islet autoantibodies • As T1D involves autoimmune destruction of pancreatic β cells • If islet autoantibodies are present, supports diagnosis of T1D Complications of diabetes Complications of diabetes • People with diabetes AND pre-diabetes have increased risk of CVD i.e. heart disease, stroke, high BP, atherosclerosis • This is known as “macrovascular complications” (disease of large vessels) Complications of diabetes • Diabetes also damages small blood vessels • Retinopathy • Nephropathy • Peripheral neuropathy • Autonomic neuropathy • Known as “Microvascular disease” • Prevalence increases with duration of diabetes and degree of metabolic control Complications of diabetes • Diabetes results in low grade inflammation and accumulation of advanced glycation end-products (AGEs) à alter cross-linking in connective tissues • Impaired wound healing - risk of ulcers/amputation • Tissue stiffness – rheumatological problems • Chronic pain Impact on physical activity Complications of diabetes • Sleep apnoea • Hearing impairment • Alzeimers disease and other dementia • Psychosocial issues Diabetic peripheral neuropathy • Affects 50% of patients with diabetes • Glove & stocking distribution • Sensory loss - numbness • +/- Neuropathic pain - burning/shooting/allodynia • Mononeuropathy eg carpal tunnel syndrome Autonomic neuropathy • Parasympathetic or sympathetic nerves may be affected in one or more visceral systems • Cardiovascular – orthostatic hypotension, resting tachycardia, fixed heart rate • Gastrointestinal/urinary – dysphagia, nausea, incontinence • Thermoregulation – cold feet, dependent oedema Charcot neuropathy • Progressive condition affecting bones of foot • Inflammation (red, hot swollen foot) then bony destruction --> subluxation, pathological fractures à deformity à remodeling of fracture • Treatment – • Acute phase - immobilization, eg aircast, avoid WB • Post-acute phase –progressive loading of tissues Rheumatological and musculoskeletal conditions • Widespread chronic pain (>3 sites) in 1 in 3 people with T2D • Adhesive capsulitis, tendinopathy, dupuytren’s contracture, limited joint mobility syndrome, osteoarthritis • Prevalence ~2 x greater in T2D than general population Psychological issues • Depression, anxiety • Fear of hypo’s • Fear of amputation • Fear of injury Impact on quality of life Hypoglycaemia • People with diabetes are at risk of hypoglycaemia, especially if: • Taking insulin or sulphonylurea drugs • Malabsorption problems eg coeliac disease, or eating disorder • Concurrent illness or other medical conditions eg renal impairment • Prolonged aerobic exercise Hypoglycaemia • Defined as blood glucose < 4mmol/L (‘4 is the floor’) • Symptoms of hypoglycaemia • Autonomic – sweating, trembling, pounding heart, hunger, anxiety • Drowsiness, speech difficulty, incoordination, irritability • Nausea, headache, tiredness Hypoglycaemia Treatment of hypoglycaemia • Depends on severity and conscious level • Try to identify the cause • Oral carbohydrate eg milk, juice, jelly beans • Repeat blood glucose measurement 5-15mins later • If remains < 4mmol/L after 3 cycles contact a doctor • Not to drive if <5mmol/L Management of diabetes Management of diabetes • Goals • Aim for HbA1c <7% • Reduce risk of microvascular and macrovascular complications + other risk factors • Promote self-management • Improve quality of life Management of diabetes • Multidisciplinary team • Endocrinologist, GP, Dietician, Diabetes Educator, Accredited Exercise Physiologist (AEP), Psychologist, Podiatrist, Physiotherapist • Regular follow-up • * Approx. 80% of all patients visiting physiotherapists in outpatient settings have diabetes, prediabetes or risk factors associated with diabetes (Hansen et al 2013) Management of diabetes • Diet + lifestyle modification • Medication • Oral antidiabetic drugs • Injections In T1D urgent treatment with insulin is required In T2D, first approach involves diet/lifestyle Medication • Drugs to reduce hyperglycaemia include: • Metformin (helps body be more sensitive to insulin) • Sulphonylureas (promotes insulin secretion) • Insulin injection –short/long acting, different dosing regimes, insulin pumps • Varied side effect profiles eg insulin has increased risk of weight gain, & hypoglycaemia Exercise for people with Pre-diabetes • >3000 “Pre-diabetics” monitored for 2.8 years • Randomised to • • Lifestyle intervention (150mins brisk walking/wk + diet) • Metformin • Placebo Results – Risk of developing T2D compared to placebo was • 58% lower risk for lifestyle group • 31% lower risk for metformin group Knowler et al. (2002) Reduction in the incidence of type 2 diabetes with lifestyle intervention or metformin. N Engl J Med 346: 393-403 Exercise for people with T2D • Exercise (12 weeks combined resistance and endurance training) shown to reduce HbA1c by 0.7-0.8% in T2D • By comparison, treatment by metformin showed same reduction • Exercise training did not change body weight (may be due to reduced fat mass but increased muscle mass) Mechanisms of effect • Acute effects of a single bout of exercise à Immediate lowering of blood glucose • Dependent on intensity /duration of activity • Stimulates glucose uptake from blood into skeletal muscle • Increased insulin sensitivity – up to 72hrs following a single bout Colberg (2019) Physical activity, exercise and diabetes Mechanisms of effect • Exercise also has benefits on • Chronic low grade inflammation (antiinflammatory effects) • Endothelial (vasodilatory) dysfunction • Reducing hypertension Colberg (2019) Physical activity, exercise and diabetes Exercise prescription for people with T2D • People with T2D should permanently (lifelong) exercise 5 days per week • Combination of aerobic and resistance exercise • 210 mins moderate intensity or 125 mins vigorous intensity • Plus 2 or more resistance training sessions per week • Exercise ideally on most days of the week Exercise prescription for people with T2D • Avoiding physical activity carries greater risks than engaging in physical activity, however precautions are needed and should consider any comorbidities • Physiotherapists should be aware of absolute and relative contraindications to exercise • Pre-participation screening can help detect risks Screening in people with diabetes • Refer to GP before initiating exercise if (Hansen et al 2013) • Untreated hypertension (BP>140/90 mmHg) • Angina • Previously undetected heart rhythm disturbances • Untreated intermittent claudication • Fasting hyperglycaemia (FBG > 16.8 mmol/L) • frequent hypoglycamic episodes • Untreated wounds in legs • Cachexia or sudden weight loss • Untreated autonomic or peripheral neuropathy or visual disturbances Screening in people with diabetes • Pre-participation screening eg. PAR-Q • Measure resting BP, HR (if BP > 140/90 mmHg or HR > 100bpm or <60bpm with clinical symptoms require further attention) • Exercise testing with continuous ECG monitoring is often done, esp if diabetes > 10 yr, hypertension, smoker, dyslipidaemia, retinopathy, nephropathy, diagnosed or suspected CAD, PAD, CVD, autonomic nephropathy Screening in people with diabetes • Evaluation of autonomic neuropathy • HR & BP changes from supine to standing (orthostatic hypotension = SBP drop > 30mmHg or DBP drop > 10mmHg • Slowed HR recovery after exercise Screening in people with diabetes • Evaluation of peripheral vascular status – pain (neuropathic or intermittent claudication), colour, temperature, pulses, nails • Evaluation of neurologic system sensation, neuropathic symptoms • Inspection of feet – colour, cracking, infection, ulcers, blisters • Musculoskeletal risk factors – deformity, muscle wasting, contracture • Falls risk • Evaluation of physical activity levels – pedometer, accelerometer, HR Screening in people with diabetes • Body composition – waist circumference, DEXA • BMI is less valid estimate esp if strength-trained individuals, older people or fluid disturbances • Physical fitness – gold standard =cardiopulmonary exercise test (CPET) – provides V02 & medical safety of exercise • Other submaximal tests e.g. 6MWT • Muscle strength – dynamometry, grip, sit-stand test Screening in people with diabetes • Physiotherapists should also be aware of conditions that might increase the risk of complications during exercise • Hypoglyceamia • Foot trauma, falls, injury • Retina damage Screening in people with diabetes • Hypoglycaemia is a common complication during exercise esp if unstable T2D. Risk factors include • Insulin or sulponylurea medications • Greater exercise volume of muscle recruitment • Pre-ex BG < 5.5 mmol/L • If BG < 4.2 mmol/L consume 15g jellybeans ahead of exercise • Have jellybeans available and monitor for symptoms Exercise for people with T2D Special considerations • Exercise with a partner, take carbohydrate • Ensure adequate fluid intake, environmental temperature • Monitor exercise responses • B-blockers affect heart rate response to exercise Exercise for people with T2D Special considerations if diabetic neuropathy or peripheral vascular disease • Regular foot inspection • Appropriate shoes • Patients who are active (even with weight bearing exercise) do not seem to increase their risk of ulcers • Limit high impact/weight bearing exercise if advanced neuropathy • Gradual increase in loads • May impact gait/balance Exercise for people with T2D Special considerations if retinopathy • Avoid higher intensity exercise • Avoid activities which elevate BP significantly – jarring, head down, valsalva Exercise for people with T1D • Special considerations • Generally, no restrictions if blood glucose (BG) is well controlled • If control is good, exercise helps lower BG • If control is poor, exercise exacerbates increased or decreased BG Exercise for people with T1D Special considerations • GOAL –at least 30 mins of moderate intensity exercise daily • Monitoring blood sugar frequently • Adjusting insulin and consumption of carbohydrates • Ideally exercise at same time of day and similar intensity • Risk of hypoglycaemia is lower with interval training Special considerations for Gestational diabetes Special considerations for Gestational diabetes • Pregnant women with or at risk of GD should engage in 20-30min of moderate intensity exercise on most or all days of the week • Stop exercise if • vaginal bleeding, dizziness, headache, chest pain, muscle weakness, preterm labour, decreased foetal movement, amniotic fluid leakage, calf pain or swelling and dyspnoea without exertion. Checklist prior to exercise • Gather relevant info on day of exercise • How are you feeling today? Any new symptoms, current health • What & when did you last eat? • What medications have you taken? • Check blood glucose level • BP, HR Physiotherapists play a role in • Assessing symptoms, medical history, musculoskeletal, orthopaedic • Monitoring functional ability • Goal setting • Long term behaviour change Communication • Optimal communication can increase motivation, health and wellbeing of people with diabetes. • Careless or negative language can be de-motivating, is often inaccurate and can be harmful. References • Davidson’s Principles and Practice of Medicine (2018) Ralston et al (Ed.) Elsevier Edinburgh • Cox et al (2019) Not a painless condition: Rheumatological and Musculoskeletal Symptoms in T2D and the implications for exercise participation. Current Diabetes Reviews • Hansen et al (2013) Exercise assessment and prescription in patients with T2D in private and home care setting References • Turner et al (2019) Resources to Guide Exercise Specialists Managing Adults with Diabetes Sports Medicine https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6546780/ • Hordern (2012) Exercise prescription for patients with T2D and prediabetes: A position statement from Exercise and Sports Science Australia JSAMS 15(2012) 25-31 • Diabetes Australia (2011) Position statement – A new language for diabetes https://static.diabetesaustralia.com.au/s/fileassets/diabetesaustralia/f4346fcb-511d-4500-9cd1-8a13068d5260.pdf THANK YOU