Diabetes MellitusTom SalterF1 Warwick Hospital

Clinical Scenario

This 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 Scenario

What 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 Scenario

Investigations• 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 Scenario

ManagementRemember 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 Management

Metformin:

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 Management

Sulfonylureas:

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 Management

DPP-4 inhibitors:

Mode of actionReduce circulating glucagon levels

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

Diabetes Medical Management

Thiazolidinediones (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 complications

DKA▫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

Summary

1. 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

References

1. 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