Diabetes MellitusTom SalterF1 Warwick Hospital

Clinical ScenarioThis is Mr Balls he has presented to his GP

feeling tired for 3 months...

What are you going to ask?▫Follow a Hx taking pattern that’s

comfortable▫Narrow down to a system▫Have about 5 set questions in mind▫R/O serious pathology▫Don’t forget social and ICE

Clinical Scenario•52 years old lethargic & tired 3/12•thirsty & drinking more than normal for

2/52•no other significant symptoms

•Hypertension on Ramipril only•No known allergies•Works as librarian, drinks socially, non-

smoker

Clinical ScenarioWhat do you think is wrong with the

patient?What would you like to examine?

O/E:•Obese (BMI 32)•Systems examinations otherwise

unremarkable

Clinical Scenario•What are your differentials and why?

▫Diabetes Mellitus▫Chronic kidney disease▫Diabetes insipidus▫Thyroid disease (Hypothyroidism)

Clinical ScenarioInvestigations• Bedside

▫ Urine dipstick (glucose and ketones), BM, ECG

• Simple▫ Glucose, FBC (?anaemia), U+Es (?CKD), LFTs

(fatty liver, albumin), TFT,▫ Urine MC&S, albumin and ?PCR (?CKD)

• Radiological▫ ?CXR, ?USS Kidney

• Special tests▫ ?Fluid deprivation test

Clinical ScenarioManagementRemember the blurb... “Managed in an

MDT approach...”•GP, Practice nurse, district nurses, OTs

dietician, retinal screening service, MDT diabetic foot clinic, consultant.

•Have a rough idea what each member does!

Clinical Scenario• Conservative

▫Smoking cessation – help and advice▫Lifestyle – weight loss, low GI diet, exercise▫Foot care▫Eye checks

• Medical▫Oral/Tablet control▫Insulin▫Control BP, cholesterol and other risk factors

• Surgical▫Islet cell transplants▫Rx of Complications e.g. amputation

Diabetes Medical ManagementMetformin:

Mode of actionSuppresses hepatic gluconeogenesisIncreases insulin sensitivity

EffectsReduces diabetic complications,Reduces serum levels of LDL and TriglyceridesParticularly important in overweight ptsGI side effects, CI if eGFR <30ml (caution if <45)

Diabetes Medical ManagementSulfonylureas:

Mode of actionIncrease insulin secretion by Beta cells Need underlying insulin production

EffectsReduce circulating glucose (risk of hypos)Generally avoided if overweightIncreased risk of hypos if renal impairment

Diabetes Medical ManagementDPP-4 inhibitors:

Mode of actionReduce circulating glucagon levels

Effects↑insulin secretion↓gastric emptying ↓blood glucoseContinue only if >0.5% ↓ in HbA1c

Diabetes Medical ManagementThiazolidinediones (glitazones):

Mode of actionActivates nuclear receptors called PPARs effecting

gene transcription

EffectsDecreased insulin resistanceIncreased free fatty acid & glucose metabolismWeight gain (↑ appetite)Pioglitazone only now (Rosi. ↑ CHD and MIs)

Diabetes Medical ManagementInsulinNICE recommends (3).. Cont. Metformin &

Sulfonylurea

1st: Intermediate NPH (porcine) insulin ON or BDOr long-acting OD if difficulty injecting

2nd: Biphasic BDparticularly if HbA1c >9% or problem with hypos

3rd: Add mealtime boluses as appropriate or consider switch to basal bolus or add thiazolidenedione

Nice T2DM Mx guidelines: http://bit.ly/GIVIAW

Insulin in Type 1•How does the insulin Mx differ?

▫Loss of intrinsic insulin secretion – Basal-bolus insulin or S/C pumps needed

▫Usually a younger presentation▫S/C pumps may allow a more normal daily

routine▫Pumps require good compliance

Diagnosis Criteria•What are the diagnostic criteria for diabetes?

▫Fasting Glucose level >7.0 mmol/L▫Random Glucose level >11.1 mmol/L

▫One reading if symptomatic or two if asymptomatic

▫Also now HbA1c of 48 mmol/mol (6.5%) can be used for diagnosing diabetes (<6.5% does NOT exclude the diagnosis)

Diagnosis Criteria•Impaired Glucose Tolerance

▫7.8 mmol/L - 11.0 mmol/L▫2 hours post 75g oral glucose tolerance

test▫Greater risk of CVD and DM than IFT

•Impaired Fasting Tolerance▫6.1 mmol/L - 6.9 mmol/L ▫Fasting serum glucose

Prognosis•75% of those with T2DM will die of heart

disease•15% of a CVA•The mortality rate from CVD is 5x higher in

those with DM (1)

•Over 60% of T1DM patients will NOT suffer serious complications. Especially if no complications by 10- 20 years post-diagnosis (5)

Complications of Diabetes

•Cardiovascular:▫Ischaemic heart disease, Cerebrovascular

disease, Peripheral vascular disease

•Renal:▫Diabetic nephropathy caused by

hyperfiltration of glucose and atheromatous changes to the blood vessels of the kidneys

Complications of Diabetes•Neuropathic:

▫Neuropathy of any nerve!▫Autonomic (GU, GI, postural hypotension)▫peripheral sensorimotor e.g glove and

stocking▫mononuritis incl. CNs▫Charcot’s foot, diabetic ulcers▫PAIN

Complications of Diabetes• Retinopathy:

▫Background

▫Pre-proliferative

▫Proliferative

• Maculopathy:

Acute complicationsHONK

▫a hyperosmolor hyperglycaemic non-ketotic state

▫T2DM

▫Usually as a result of dehydration and illness▫Inability to take diabetic medication

▫Symptoms weakness, cramps, visual impairment, confusion seizures +/- nausia & vomiting (less than DKA)

Acute complicationsHONKManagement:

▫A-E approach▫Fluid resuscitation with normal saline▫Electrolyte replacement esp. potassium▫Insulin (aiming for SLOW reduction of

serum glucose, approx 3mmol/hr)▫Senior guidance for insulin sliding scale▫VTE prophylaxis

Acute complicationsDKA

▫Ketonaemia (>3 mmol/L), or ketonuria (>2+)▫Bicarbonate <15 mmol/L or venous pH <7.3▫Blood glucose >11 mmol/L or known DM (not

a good indicator of severity)

▫Caused by infections, non-compliance, acute illnesses (e.g. PEs, thyroid disease etc), CVD/MI

Acute complicationsDKASymptoms:

polydipsia, polyuria, nausea & vomiting, abdominal pain

Management:Correct dehydration with IV crystaloidsReduce glucose 3mmol/L/hourRegularly monitor potassium (ECG)Do not routinely give bicarbonate or phosphateTreat the underlying illnessContinue to monitor fluid balance & electrolytes 1-2

hourly

Summary1. Diagnosis >7.0mmol/L (fasting)

>11.1mmol/L (random)

2. Minimise risk factors and maintain tight control

3. Diabetes complications: Heart, Kidneys, Eyes & Nerves PLUS DKA in T1DM, HONK in T2DM

References1. http://www.patient.co.uk/doctor/diabetes-mellitus2. http://www.patient.co.uk/doctor/management-of-type-2-di

abetes3. http://bit.ly/GIVIAW (NICE)4. http://bit.ly/GKfqM1 (NICE)5. http://emedicine.medscape.com/article/117739-overview