Obesity/Diabetes Flashcards
Describe Type 1 Diabetes:
- cause
- prevalence
- treatment
- symptoms
- diagnosis
T1D is an autoimmune condition in which the pancreatic β-cells do not produce insulin.
Cause:
- Autoimmune condition
- Exact cause unknown
- Family history (several genes linked to T1D)
- Environmental trigger e.g., viral infection
Prevalence:
- Typically diagnosed in childhood/adolescence
Treatment:
- Insulin
Symptoms:
- 4 T’s (toilet, thirst, thinner, tired)
- Increased hunger
- Dizziness
- Blurred vision
Diagnosis:
- HbA1c level >48mmol/mol
- Random Plasma Glucose (RPG) >11.1 mmol/L
- Fasting Blood Glucose test >7 mmol/L
- Oral Glucose tolerance test (OGTT)
Describe Type 2 Diabetes:
- cause
- risk factors
- prevalence
- treatment
- symptoms
- diagnosis
T2D is a condition characterised by inadequate response to insulin by insulin receptors on cell membrane - insulin resistance.
Most common form of diabetes (90% cases).
Cause:
- Overweight and obesity
- Family history
Risk factors:
- Genetic links
- Overweight/obesity (central obesity). Excess adiposity reflected by higher body mass index (BMI) is the strongest risk factor for diabetes
- 80% of individuals diagnosed with T2D are overweight
- Ethnicity (South Asian, Black African, African Caribbean at higher risk).
- History of polycystic ovaries, gestational diabetes or macrosomic birth.
Prevalence:
- Older adults
- Overweight/obese people
- Becoming more common in younger people
Treatment:
- Lifestyle modifications (diet & exercise)
- Antidiabetic Therapies (Metformin, Sulphonylureas, GLP1, Acarbose, Gliptin)
- Insulin
Symptoms:
- 4 T’s (toilet, thirst, thinner, tired)
- Increased hunger
- Dizziness
- Blurred vision
- Itching
- Slow wound healing
- Candida type infection
Diagnosis:
- HbA1c level >48mmol/mol
- Random Plasma Glucose (RPG) >11.1 mmol/L
- Fasting Blood Glucose test >7 mmol/L
- Oral Glucose tolerance test (OGTT)
What are the acute and chronic complications of diabetes?
Acute:
- Hypoglycaemia or hyperglycaemia
- Hyperosmolar Hyperglycaemic State (HHS):
life-threatening emergency brought on by severe dehydration + very high blood sugars (only in T2D). - Diabetic ketoacidosis (DKA):
life-threatening emergency where lack of insulin and high blood sugars leads to a build-up of ketones as fat is used for energy. Ketones can build up and make your blood become acidic (only in T1D).
Chronic:
- Retinopathy
- Foot problems
- Heart attack and stroke
- Kidney problems (nephropathy)
- Nerve damage (neuropathy)
- Gum/other mouth problems
- Cancer
- Sexual problems (men & women)
Describe a proposed mechanism for the development of insulin resistance:
- PI3K/AKT signalling pathway
Chronic hyperinsulinaemia causes the down regulation of insulin receptors.
Disruption of insulin signalling pathways caused by IR and obesity.
A significant reduction in insulin-stimulated PI3K pathway has been noted in the muscle tissues of obese humans.
Suggested that FFA (Free fatty acids) lead to a reduction in PI3K activity
- In insulin-resistant humans, an impairment of AKT phosphorylation has been reported.
Briefly describe how T2D can be prevented.
50% of cases of T2D can be avoided if prevention strategies are implemented.
Weight management:
- Losing just 5% of body weight can significantly reduce risk
Diet:
- DASH (dietary approach to stop hypertension)
- Mediterranean diet
- High fibre, low GI, low foods
- Low carb, high protein diet
Physical activity:
- both aerobic and resistance training
What are the primary goals of diabetes treatment?
- how is this achieved?
- what are diabetes management strategies for T1D & T2D?
To bring the elevated blood sugars down to a normal range:
- to improve symptoms of diabetes
- to prevent or delay diabetic complications
Achieving this goal requires a comprehensive, coordinated, patient-centred approach on the part of the health care system.
Strategies:
T1D:
- insulin replacement
- diet & lifestyle modification
T2D:
- diet & exercise regime
- antidiabetic therapy (used alongside diet & exercise regime if diet & exercise alone unsuccessful
What are the most common antidiabetic drugs?
Describe the action of Metformin.
- Metformin (1st line antidiabetic therapy)
- Sulphonylureas (2nd line antidiabetic therapy)
- Gliptin
- GLP1
- Insulin
Metformin:
First line therapy for new diagnosis of T2D.
Decreases hepatic glucose production and intestinal absorption & increases peripheral glucose uptake.
Metformin helps the body to control blood glucose:
* Helps T2 diabetics respond better to own insulin
* Lowers amount of glucose created by the liver
* Decreases glucose absorption by the intestines
What are the dietary recommendations for people with T2D?
What are the 6 dietary principles of diabetes management?
NICE guidelines:
People with T2D given same advice RE healthy eating as general population.
Dietary management should include:
- Individualised care
- Diabetes education
- Dietary advice:
Eat regular lower GI meals (40-60% total cals from low GI carbs)
Reduce intake of simple sugar ( <10% total energy) however sucralose may not affect glycaemic control negatively.
Aim for 5 portions of fruit and vegetables per day
Reduce sat fat & consume low fat dairy products
Reduce salt intake
Aim for 2 x fish per week – 1 oily*
Alcohol in moderation
*Omega 6 improves insulin sensitivity: FA profile of diet determines FA profile of phospholipid bilayer of cells = increased insulin sensitivity
Describe the role of fibre in diabetes management.
Observational studies suggest that dietary fibre (of any type) is associated with lower HbA1c levels.
Longer-term (more than six months) studies investigating the benefits of a high fibre intake are limited.
Some studies using large amounts of fibre (40–50g/day) report improved glycaemic control, but there is with little evidence supporting smaller amounts.
?realistic - encourage them to achieve recommended intake (30g).
Higher intakes of soluble fibre has beneficial effects on CVD/CHD (improves gut health and reduces cholesterol).
- Diet rich in fibre may reduce diabetes risk:
inverse association between fibre and type 2 diabetes risk - strongest in cereal fibre.
Describe the role of carbohydrates in diabetes management.
- what are the implications for people with T1D
- what are the implications for people with T2D
CHO is the most important macronutrient influencing post prandial blood glucose concentration.
NICE recommends 40-60% total cals come from low GI carbs
Factors to consider:
- total amount CHO
- type/quality of CHO
- GI index/load
T1D:
Twice-daily insulin - consistent amount of CHO amount/type/timing on a day-to-day basis.
Basal bolus insulin (injections or pump) - more flexibility with CHO intake.
Carb counting for insulin dose adjustment.
DAFNE course available.
T2D:
Low carb diet for weight loss
Low GI diet
increase fibre content
2014 systematic review published in Lancet:
- Proportion of CHO in diet does not notably influence diabetes risk and CHO quality more important.
- Diet rich in fibre may reduce diabetes risk:
inverse association between fibre and type 2 diabetes risk - strongest in cereal fibre. - Meta-analyses found low GI and GL diets associated with lower risk for diabetes compared with diets with higher GI and GL.
What is the role of weight management in the management of T2D diabetes?
NICE guidelines recommend initial weight loss target 5-10% for T2D.
Weight loss can improve glycaemic control and reduce cardiovascular risk and all cause mortality in people with T2D.
5-7% weight reduction known to have beneficial effect on diabetes. Some research shows benefits from just 3% weight reduction.
- Weight loss of 5% improves multi-organ insulin sensitivity and b-cell function.
- Weight loss of 11%–16% increases insulin sensitivity in muscle.
- weight loss can be achieved by DiRECT trial or bariatric surgery.
What is HHS and DKA?
Hyperosmolar Hyperglycaemic State (HHS):
life-threatening emergency brought on by severe dehydration + very high blood sugars (only in T2D).
Diabetic ketoacidosis (DKA):
life-threatening emergency where lack of insulin and high blood sugars leads to a build-up of ketones as fat is used for energy. Ketones can build up and make your blood become acidic (only in T1D).
Describe methods of weight loss for obesity/T2D
Bariatric surgery:
invasive and last resort method of weight loss
Usually only offered to people who have a BMI > 40 or BMI 35-40 + obesity related condition e.g., T2D.
Gastric sleeve or gastric bypass most common types of bariatric surgery - main goal to shrink the size of the stomach –> early satiety –> consume less food.
DiRECT trial:
The Diabetes Remission Clinical Trial (DiRECT) designed to determine whether a structured, intensive, weight management programme, delivered in a routine Primary Care setting, is a viable treatment for achieving T2D remission.
Aim: increase the number of people who can become non-diabetic
- secondary aim: reduce NHS healthcare costs (drugs cost the NHS around £800million per year).
Findings:
as of April 2023 - 23% of ppl remain in remission after 5 years following trial (3x more than control group)
however, number of ppl in remission is decreasing as time goes on
? long term sustainability/success of diet.
