Topic 4.2: Diabetes

diabetes

* a disease characterized by the %%abnormal use%% of %%carbohydrates%% by the body and %%elevated blood glucose%% levels

symptoms of type 1 diabetes

* increased %%frequent urination%%
* excessive %%thirst%%
* constant %%hunger%%
* unexplained %%weight loss%%
* extreme %%fatigue%%
* blurry %%vision%%

symptoms of type 2 diabetes

* any %%type 1 symptoms%%
* greater %%frequency of infections%%
* sudden %%vision changes%%
* %%slow healing%% of wounds and sores
* %%tingling or numbness%% in the hands and feet
* very %%dry skin%%

prevalence

* the proportion of a population who have a specific characteristic in a given time period
* the prevalence of diabetes has %%dramatically increased over time%%

diabetes prevalence

* %%United Nations%% recognize diabetes as a global issue
* %%primary predictor%% of diabetes is %%obesity%%
* %%3.7 million deaths%% due to diabetes and high blood glucose
* %%1.5 million deaths%% caused by diabetes
* %%422 million%% adults have diabetes
* %%1 in 11%% people
* %%11 million Canadians%% living with diabetes or pre-diabetes

normal fasting plasma glucose

* %%4 - <7%% mmol/L

blood glucose homeostasis

* when a person %%eats carbohydrates%%, blood glucose levels rise
* if blood glucose levels get too high, the %%pancreas is stimulated to release insulin%%

insulin stimulates:

* uptake of glucose into the cells
* storage of glucose as glycogen into the liver and muscles
* storage of excess glucose as fat


2. as the body uses glucose, %%blood levels decline%%

blood glucose homeostasis (continued)

* low blood glucose levels stimulates the pancreas to release %%glucagon%%
* glucagon stimulates the cells to %%release breakdown glycogen stores%% and %%release glucose%% into the blood to bring blood glucose levels into homeostasis.

%%outside normal%% blood glucose range

high blood glucose

* high blood triglycerides
* high bp
* hardening of the arteries

starved for Glucose: if insulin insufficient or cell membranes not sensitive

* cells become starved

classification of diabetes

__type 1 diabetes mellitus (DM)__

* %%beta cell destruction%%
* usually leading to %%absolute insulin deficiency%%

__type 2 diabetes mellitus (DM)__

* predominantly %%insulin resistance%% with relative %%insulin deficiency%%
* predominantly a %%defect insulin secretion%% with %%insulin resistance%%

__gestational diabetes mellitus (GDM)__

* %%glucose intolerance%% first recognized during %%pregnancy%%

diabetes type 1 and 2 compared

proportion of cases

type 1: %%5-10%%%

type 2: %%90-95%%%

health consequences of unmanaged diabetes

long-term, poorly managed blood sugar may contribute to:

* %%heart disease (#1)%%
* hypertension
* blindness
* kidney failure
* stroke
* loss of limbs due to poor circulation

type 1 diabetes management

medical management

* __insulin injections required for life__

lifestyle management

* adequate nutrient intake
* adequate fibre
* adequate protein
* adequate fat

moderate:

* added sugars
* total carbohydrate

physical activity!!

type 2 diabetes management

medical management

* insulin stimulating drugs
* insulin injections

lifestyle management

* same as type 1

weight loss

physical activity!!

risk factors for type 2 diabetes

1. __age__

* most common in %%individuals over 40%%
* increasing incidence in %%children%% and %%adolescents%%


2. __obesity__
3. __physical inactivity__
4. __genetics__

* familial history
* people of african, hispanic, canadian aboriginal, asian or pacific descent

diagnosis of type 2 diabetes

* occurs at %%7 mmol/L FPG%% (fasting plasma glucose)
* ineffective %%insulin receptors%%
* %%inadequate%% amounts of insulin
* usually %%pre-diabetes comes first%%

prediabetes

* usually people who develop type 2 diabetes have pre-diabetes first
* pre-diabetes range is %%above normal levels%% and %%below diagnosis%%
* approximately %%6.1 – 6.9 mmol/L FPG%%
* Having the condition of pre-diabetes increases risk of diabetes %%10% per year%%
* %%\~50% of people%% with pre-diabetes will develop diabetes
* most people diagnosed with pre-diabetes have a condition known as insulin resistance

A1C / HbA1C / glycosylated hemoglobin

* hemoglobin is part of your red blood cells that carry oxygen from your lungs to the rest of the body
* once a %%hemoglobin is glycated,%% it remains that way in the blood, until the red blood is removed

A1C blood test

* A1C blood test reports the %%percentage (%) of hemoglobin%% that is %%bound to glucose%%
* A1C represents the blood glucose for the %%past 3 months%% or so

notes about Hb1AC test

1. not used for %%gestational diabetes assessment%%
2. %%less accurate%% for diagnosing diabetes for individuals who have

* anemia
* other blood disorders
* experienced a %%recent blood loss or transfusion%%

3\. individuals of %%African, Mediterranean, or Southeast Asian%% descent may have uncommon forms of hemoglobin that produce falsely high or low results

mechanism of insulin resistance

1. insulin binds cell membrane receptors

* Activated receptors, allow glucose into cells
* Cell membranes ‘resist’
* lower transport, increases blood glucose


2. pancreas responds by producing more insulin

* higher insulin keeps glucose levels under control for years
* %%pancreas becomes exhausted%%
* Tthe pancreas %%slows or stops%% producing insulin and glucose levels increase in the blood

type 1 diabetes

* 9% of all cases
* insulin is released by the 'beta cells' in the islets of Langerhans
* %%insulin deficiency%%
* diagnosis peaks \~ 10-14 years and usually occurs before age 40
* insulin deficiency from %%person’s own immune system attacking and killing pancreas%%
* destroys the portion of pancreas that produces insulin

how is the immune system provoked to attack?

• genetic predisposition

• viral infection

• other diseases

• toxins

• allergens

• disordered immune system

%%\*\*breastfeeding for first four months may confer protection against type 1 diabetes%%

gestational diabetes (GDM)

* no pre-existing diabetes prior to becoming pregnant
* %%3 to 20%%% of women develop gestational diabetes
* disappears after birth but may return later in life
* prevention includes exercise, maintaining a normal weight, eating a healthy diet

gestational diabetes problems and management

infants of women with unmanaged gestational diabetes may:

* be fat at birth
* have blood glucose control problems after delivery
* have an increased risk of diabetes later on in life

management involves:

* an individualized diet with exercise
* the possibility of insulin