Diabetes

Introduction to Diabetes

What is Diabetes?

Think of your body like a car. Glucose (sugar) is its fuel. Insulin, a hormone made by your pancreas, is the key that unlocks your cells to let the glucose fuel in. Diabetes is a condition where this system doesn't work properly. Either you don't have the "key" (insulin) at all, or the "lock" on your cells is rusty and doesn't respond to the key.

* Normal Blood Glucose Range: 4-5.6 mmol/L. The goal of diabetes management is to keep your blood sugar as close to this range as possible.

The Two Main Types of Diabetes:

1. Type 1 Diabetes (T1DM): The "No Key" Problem

* What happens? The body's immune system mistakenly attacks and destroys the insulin-producing cells in the pancreas. The body stops making insulin.

* Who gets it? Often diagnosed in children and young adults, but can occur at any age. It accounts for about 10% of all diabetes cases.

* Symptoms: Come on quickly (weeks) and include extreme thirst, frequent urination, rapid weight loss, and tiredness.

2. Type 2 Diabetes (T2DM): The "Rusty Lock" Problem

* What happens? The body still makes insulin, but the cells don't respond to it properly (this is called insulin resistance). Over time, the pancreas can also get tired and not make enough insulin.

* Who gets it? The most common type (about 90% of cases). It's often linked to being overweight, and is most common in adults over 40, but is now seen in younger people due to rising obesity.

* Symptoms: Similar to T1DM but are usually less severe and come on more slowly (over months).

Managing Type 2 Diabetes (T2DM)

#### How is T2DM Diagnosed?

A doctor will use one of these tests:

* Fasting Blood Glucose: ≥ 7.0 mmol/L (after not eating for 8 hours).

* Random Blood Glucose: ≥ 11.1 mmol/L (taken at any time of day).

* HbA1c Test: ≥ 48 mmol/mol (or 6.5%). This is a very important test as it gives an average of your blood sugar control over the last 2-3 months.

#### Step-by-Step Treatment for T2DM

Step 1: Lifestyle Changes (The Foundation)

This is always the first step. It's about helping your body use insulin better.

* Diet: Eat a balanced diet with high-fibre foods (like vegetables, wholegrains), and control saturated fats. Spreading your food intake over the day helps avoid big sugar spikes.

* Weight Loss: Losing 5-10% of your body weight if you are overweight can have a huge impact.

* Exercise: Aim for at least 150 minutes of moderate activity per week.

* Smoking Cessation: Smoking greatly increases the risk of heart problems for people with diabetes.

Step 2: First Medication - Metformin

If lifestyle changes aren't enough after 3 months, the first pill usually prescribed is Metformin.

* How it works: It mainly tells your liver to make less sugar and helps your muscles use sugar better. It doesn't cause weight gain.

* Side Effects: Can cause stomach upset (nausea, diarrhoea), but this often gets better. An extended-release version can help.

* Warning: It's used with caution in people with kidney problems.

Step 3: Adding More Medications

If blood sugar is still too high, a second (and sometimes third) drug is added. The choice depends on the patient's other health conditions.

| SGLT2 Inhibitors ("Flozins") | Empagliflozin, Dapagliflozin | Makes you pee out excess sugar. | Great for the heart! Preferred if you also have Heart Failure or high CVD risk. Warning: Can cause genital thrush. Rare risk of a serious infection called Fournier's gangrene. |

| GLP-1 Receptor Agonists ("-tides") | Liraglutide, Dulaglutide | Injected drugs that mimic a gut hormone to increase insulin, reduce appetite, and slow stomach emptying. | Great for weight loss and heart health. Often used in obese patients.

| DPP-4 Inhibitors ("-gliptins") | Sitagliptin, Linagliptin | Boosts your body's own insulin-releasing hormones. | Neutral: Doesn't cause weight gain or hypoglycaemia. A safe, common choice. |

| Sulfonylureas | Gliclazide, Glimepiride | Pushes the pancreas to release more insulin. | **Strong effect.** Main risk: Can cause low blood sugar (hypoglycaemia) and weight gain. |

| Thiazolidinediones | Pioglitazone | Makes the body's cells more sensitive to insulin. | Risks: Can cause fluid retention, worsening heart failure, weight gain, and a small risk of bladder cancer. Rarely a first choice. |

Step 4: Insulin Therapy

If pills and non-insulin injections are no longer controlling blood sugar, insulin injections are started.

Managing Type 1 Diabetes (T1DM)

Since the body makes no insulin, people with T1DM must take insulin for life.

Types of Insulin

Insulins are categorized by how quickly and how long they work.

| Rapid-Acting (Short) | Novorapid, Humalog | 15 mins | Taken with meals to cover the sugar from food. |

| Long-Acting (Basal) | Lantus, Levemir | 1-2 hrs, lasts up to 24 hrs | Provides a background level of insulin 24/7, even when not eating. |

| Mixed Insulins (Pre-mixed) | Novomix 30, Humulin M3 | A combination of rapid and intermediate | Covers both meals and background needs in one injection. Less flexible. |

Insulin Regimens (Schedules)

* Basal-Bolus Regimen (The Gold Standard): This mimics how a normal pancreas works.

* Bolus: A dose of rapid-acting insulin is taken before each meal.

* Basal: One or two doses of long-acting insulin are taken to provide background coverage.

* Insulin Pumps: A small device worn on the body that delivers a continuous trickle of rapid-acting insulin (the basal) and allows for bolus doses at mealtimes.

Key Skills for T1DM Management

1. Carbohydrate Counting:

* You learn to estimate the grams of carbohydrates in your meal.

You have a personal *Insulin-to-Carb Ratio (ICR)** (e.g., 1 unit of insulin for every 10g of carbs).

* Calculation: Carbs (g) ÷ ICR = Insulin Dose.

* Example: 60g of carbs ÷ ICR of 1:10 = 6 units of insulin needed.

2. Correction Dose:

* This is an extra dose of insulin to bring a high blood sugar level back down to your target.

You have a *Correction Factor (or Insulin Sensitivity Factor)** – how much 1 unit of insulin will lower your blood sugar (e.g., 1 unit lowers it by 2 mmol/L).

* Calculation: (Current BG - Target BG) ÷ Correction Factor = Correction Dose.

* Example: BG is 16, target is 8. Difference is 8. Correction Factor is 1:2. 8 ÷ 2 = 4 units correction dose.

Monitoring Your Diabetes

* Blood Glucose Meter (Finger Prick): The classic way to check your sugar at any moment.

* Flash Glucose Monitors (e.g., Freestyle Libre): A sensor you wear on your arm that you scan to see your current sugar level and a trend arrow.

* Continuous Glucose Monitors (CGM): A sensor that sends real-time sugar levels to your phone or receiver every few minutes, showing trends and alerting you to highs and lows.

* HbA1c Test: The crucial 2-3 month average, checked every 3-6 months. The target for T1DM is generally 48 mmol/mol (6.5%) or lower.

Acute Complications (Emergencies)

1. Hypoglycaemia (A "Hypo" - Low Blood Sugar)

* Causes: Too much insulin, not enough food, too much exercise.

* Symptoms: Sweating, shaking, anxiety, palpitations, confusion, drowsiness.

* Treatment (If Conscious):

* Step 1: Take 15-20g of fast-acting sugar (e.g., 3-4 glucose tablets, a small glass of fruit juice, a sugary drink).

* Step 2: Wait 15 minutes and check again. If still low, repeat Step 1.

* Step 3: Once blood sugar is above 4 mmol/L, eat a longer-acting snack (e.g., a sandwich, a biscuit) to keep it stable.

* Treatment (If Unconscious):

* This is an emergency. Do NOT give anything by mouth.

An injection of *Glucagon** can be given (if available), or emergency services should be called for intravenous glucose.

2. Diabetic Ketoacidosis (DKA)

* What is it? A severe, life-threatening condition caused by a critical lack of insulin. The body starts burning fat for fuel, producing acidic chemicals called ketones, which poison the blood.

* Who gets it? Mostly people with T1DM. It can be triggered by illness, infection, or missing insulin doses. (**Note:** Some T2DM medications, SGLT2 inhibitors, can also rarely cause DKA).

* Symptoms: Nausea/vomiting, abdominal pain, deep rapid breathing, breath smelling like nail polish remover (ketones), drowsiness.

* Treatment: Requires immediate hospital care with IV fluids and IV insulin.

3. Hyperosmolar Hyperglycaemic State (HHS)

* What is it? A very high blood sugar (often ≥30 mmol/L) causing severe dehydration.

* Who gets it? Typically older adults with T2DM.

* Symptoms: Extreme thirst, frequent urination, severe dehydration, confusion, drowsiness.

* Key Difference from DKA: There are no ketones.

* Treatment: Requires hospital care with large amounts of IV fluids and insulin.

Long-Term Complications

Long-term high blood sugar can damage blood vessels and nerves.

Macrovascular Complications (Large Vessels)

Increased risk of *heart attack, stroke, and poor circulation** in the legs. Diabetes is a major risk factor for heart disease.

Microvascular Complications (Small Vessels)

1. Retinopathy: Damage to the blood vessels in the back of the eye (retina), which can lead to blindness. (Annual eye screening is essential).

2. Nephropathy: Kidney damage.

Screened for by testing for *microalbuminuria** (small amounts of protein in the urine).

Treated with medications like *ACE inhibitors or ARBs** (even if blood pressure is normal) to protect the kidneys.

3. Neuropathy: Nerve damage.

Can cause *numbness, tingling, or pain** in the hands and feet.

Pain can be treated with medications like *pregabalin, duloxetine, or gabapentin**.

Loss of sensation in the feet is a major risk factor for *diabetic foot ulcers**.

The Diabetic Foot

* Why it matters: Reduced blood flow and numbness can lead to sores that don't heal, get infected, and can lead to amputation.

* Foot Care: Regular inspection, wearing proper footwear, and professional foot checks are vital.

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Special Situations

Diabetes and Surgery

* Pills: Some are stopped before surgery (especially SGLT2 inhibitors and Sulfonylureas) to avoid dangerous lows or ketoacidosis. Metformin may be stopped if kidney function is a concern.

* Insulin: People with diabetes often are switched to an IV insulin drip during major surgery for precise control.

* Goal: Careful management to avoid both high and low blood sugar during the stress of an operation.

Diabetes and Pregnancy

* Pre-existing Diabetes: Excellent blood sugar control before conception is crucial to reduce the risk of birth defects. Targets are tighter (HbA1c < 48 mmol/mol).

* Gestational Diabetes: Diabetes that develops during pregnancy. It is managed first with diet and exercise, then with Metformin or Insulin if needed. It usually goes away after birth.

Educational Programs

* **T2DM:** DESMOND and X-PERT programs teach self-management skills.

* **T1DM:** DAFNE program teaches advanced skills like carbohydrate counting and insulin dose adjustment.

QUESTIONS

Question 1:

A 55-year-old man with new T2DM has tried lifestyle changes for 3 months. His HbA1c is 69 mmol/mol. BP 140/85, LDL 3.4, eGFR 110. What is the best first medication?

* A. Glimepiride | B. Sitagliptin | C. Liraglutide | D. Empagliflozin | E. Metformin

Answer: E. Metformin

* Explanation: According to guidelines, the first medication to start after lifestyle changes fail is always Metformin. The patient has no other conditions (like heart failure) that would justify starting a different drug first. His kidneys are fine (eGFR 110), so Metformin is safe.

Question 2:

A 65-year-old man with T2DM and Heart Failure is on Metformin and Lisinopril. His HbA1c is 75 mmol/mol. What is the best drug to add?

* A. Empagliflozin | B. Gliclazide | C. Pioglitazone | D. Sitagliptin | E. Dulaglutide

Answer: A. Empagliflozin

* Explanation: This patient has heart failure. SGLT2 Inhibitors (like Empagliflozin) have proven, strong benefits for protecting the heart and are a top choice for patients with this condition. Pioglitazone is dangerous in heart failure, and Gliclazide doesn't provide the same heart benefits.