Diabetes Mellitus

Prof Seamus Sreenan

Dept of Diabetes and Endocrinology, Connolly Hospital, Blanchardstown

Mini Med School

November 30th, 2011

Learning ObjectivesLearning Objectives

At the end of this talk you should understand:– What diabetes mellitus means– The difference between types-1 and -2 diabetes– How the different types are treated– The reasons for the current epidemic of

diabetes and how it can be prevented– What the complications of diabetes are and how

they can be prevented

What is Diabetes?

Diabetes Mellitus (sugar diabetes) is a disease characterized by high levels of sugar (glucose) in the blood

Fasting glucose ≥ 7.0 (mmol/L)

Insulin is producedby the pancreas whenblood sugar is high

Insulin keeps bloodsugar level withinthe normal range for health

Blood sugar and health

Sugar (glucose) is an important source of energy

What is eaten is absorbed into the blood

Islet of Langerhans:Islet of Langerhans:

Insulin-cells

Pancreas contains insulin-making cells in “islets”

Diabetes in a ‘nutshell’Diabetes in a ‘nutshell’ Insufficient insulin to meet the body’s needs

Either a complete lack (type 1) or relative lack (type 2)

Results in raised blood glucose levels

Untreated diabetes results in short-term symptoms and

serious long-term complications

Treatment aims to keep blood glucose levels as close to the

normal range as safely possible

Complications of DiabetesComplications of Diabetes

Short term:– Symptoms of diabetes– Dehydration– Diabetic Coma– Infections

Long term:– Kidney– Eye– Heart– Circulation– Amputation

Symptoms of Diabetes

People with diabetes often have typical complaints (symptoms):

Thirst and frequent drinking

More frequent urination, particularly at night

Unexplained weight loss

Fatigue

Blurred vision

Frequent infections : skin, genital

Case 1Case 1

JN 32 year old male Referred to Emergency Dept by GP Complaining of thirst, excessive urination, half stone

weight loss in the last 6 weeks No relevant past history First cousin has diabetes on insulin On no regular medications Thin man Blood sugar level = 24.7 mmol/L

What type of diabetes does What type of diabetes does JN have?JN have?

There are 2 main types of diabetes:

Type 1 (15%): Due to total lack of insulin – insulin treatment is required for life

Type 2 (85%): Plenty of insulin which does not work very well in the body. Insulin treatment may be

required at some stage but is not required in all patients

Differences between type-1 and Differences between type-1 and type-2 Diabetes Mellitustype-2 Diabetes Mellitus

Type 1 Young age Normal BMI, not obese No immediate family

history Short duration of

symptoms (weeks) Can present with diabetic

coma (diabetic ketoacidosis)

Insulin required

Type 2 Middle aged, elderly Usually overweight/obese Family history usual Symptoms may be present

for months/years Do not present with

diabetic coma Insulin not necessarily

required Previous diabetes in

pregnancy

These differences are not absolute

JNJN

Young ageThinNo immediate family historyShort duration of symptoms

Insulin treatment required

All point to probable type-1 diabetes

Patient J.L., December 15, 1922

February 15, 1923

The Miracle of InsulinThe Miracle of Insulin

Treatment of Type-1 Diabetes Treatment of Type-1 Diabetes Mellitus: Mellitus:

Insulin must be administered into the subcutaneous pocket between fat & muscle & avoid injection into fat or muscle.

Can be administered by needle and syringe or by pen device

Alternative way to deliver insulin treatment:

Continuous insulin infusion (insulin pump)

Islet replacement treatmentIslet replacement treatment

Aim to replace the need for insulin treatment

(Kidney) Pancreas transplantationIslet transplantation – not available in

IrelandAnti-rejection drugs requiredStem cell transplantation - experimental

Case 2Case 2 Ms AJ, a 45 year old woman is concerned she may have diabetes She had diabetes during her last pregnancy managed with diet Lately she has been feeling tired but otherwise has no complaints Her mother and one of her two sisters already have diabetes

treated with tablets She has been overweight since her last pregnancy and has taken a

tablet for blood pressure for the last 2 years She is obese, body mass index 34.5 Blood pressure is 140/90 but otherwise her examination is

normal She undergoes a testing and her fasting glucose is 9.4 mmol/L Obese, strong family history, aged in 40s, previous history of

diabetes in pregnancy all point to type-2 diabetes

Normal Prediabetes Type 2 diabetes

After meal glucose

Abnormalglucose tolerance

Insulin resistance

Increasing insulinresistance

Fasting glucose

High sugar levels

Insulinsecretion

Hyperinsulinemia,then islet cell failure

Adapted from International Diabetes Center (IDC), Minneapolis, Minnesota.

Natural History of Type 2 Diabetes

Diet/exercise

Oralmonotherapy

Oral combination

InsulinOral

+/- insulin

Treatment of Type-2 DiabetesTreatment of Type-2 Diabetes

Diet and exercise my control condition for some time

Variety of tablets available when diet exercise no longer work

Tablets can be used in combination with each other or with insulin

Insulin can also be used alone

Prevalence of Diabetes

Diabetes is very common

It is becoming more common (particularly type-2)

It affects about 200,000 Irish people

10% of the health budget spent on diabetes

Reason for increasing prevalence of type-2 diabetes

The disease is reaching epidemic proportions because:

Rates of overweight/obesity have increased

We have become a physically inactive species

Our diets are increasingly unhealthy

Overweight and obesity are diagnosed by measuring weight and height (Body Mass Index (BMI)):

Weight in Kg

Height in metres2

Normal = 20-25

Overweight = 25-30

Obese = more than 30

Everyone should know their BMI!

BMI =

Can Diabetes be Prevented?

To be able to prevent a disease we need to be able to indentify people at particular risk of developing it

Risk factors for type 2 diabetesCertain people are more at risk of diabetes:

Those who are overweight/obese

People with a family history of diabetes

Women who had diabetes during pregnancy or have had a baby weighing more than 9lbs

Physically inactive people

Certain ethnic groups (african, american indian, asian)

People who have high blood pressure or high cholesterol

Age more than 45 years

Can Diabetes be Prevented?

Risk of Type 2 Diabetes can be reduced:

Losing weight

Taking regular exercise : walking for 30 mins per day

Eating healthier food:

Less fat (burgers, fries, crisps, sweet foods)

More fibre (fruit and vegetables, wholegrain alternatives for rice, bread)

Cutting down on alcohol consumption

Ultimate aim is to reduce the longterm complications

Can the longterm complications Can the longterm complications be prevented?be prevented?

Type-1– 1993: Study showed for the first time that good sugar

control can prevent long term complications affecting eyes/kidneys/nerves

Type-2– 1998: Similar study showed same conclusion for type-2

Important therefore to know that sugar control is good and monitor frequently

Diabetes Mellitus: Self Monitoring Diabetes Mellitus: Self Monitoring SMBGSMBG

Patients can draw blood frequently to monitor their glucose levels.

A glucose monitor is used to check the sugar as required

Glycosylated Hemoglobin: Glycosylated Hemoglobin: HbAHbAlclc

Blood test that measures the amount of glucose that has been incorporated into the hemoglobin protein of the red blood cell (RBC).

Reflects the lifespan of a RBC, so test will reveal the effectiveness of diabetes therapy for the preceding 8-12 weeks.

HbA1c levels remain more stable than sugar levels. Not affected by short-term fluctuations in sugar Normal is 4-6% Evaluated periodically (1-2 per year if well

controlled, more frequently if not)

DCCT, Diabetes Control and Complications Trial.

1. Adapted from Skyler JS. Endocrinol Metab Clin North Am. 1996;25:243-254.2. DCCT. N Eng J Med. 1993;329:977-986.3. DCCT. Diabetes. 1995;44:968-983.

Rela

tive R

isk (

%)

Rela

tive R

isk (

%)

A1c (%)A1c (%)

1515

1313

1111

99

77

55

33

1166 77 88 99 1010 1111 1212

A1c and relative risk of A1c and relative risk of complicationscomplications (type 1 diabetes)(type 1 diabetes) ::

RetinopathyRetinopathyNephropathyNephropathy

NeuropathyNeuropathyMicroalbuminuriaMicroalbuminuria

2020

Aim for AIc of < 7%

How to prevent the complicationsFactors other than blood sugar increase likelihood of complications and should be managed

Complications can be delayed/prevented by:

Controlling blood sugars: sticking to diet/exercise programme, taking medication as prescribed

Controlling blood pressure: diet, salt restriction, medication

Controlling cholesterol levels: diet, statin tablets

Stopping smoking

Taking aspirin?

Useful websitesUseful websites

Diabetes Federation of Ireland:– www.diabetes.ie

American Diabetes Association– www.diabetes.org

Irish Nutrition and Dietetic Institute– www.indi.ie

Juvenile Diabetes Research Foundation– www.jdrf.org