Type 2 Diabetes
Definition
Type 2 diabetes is caused by a combination of
insulin resistance and
relative insulin deficiency (where the pancreas is unable to secrete enough insulin to compensate for this resistance)
Risk factors
Obesity, family history, ethnicity, gestational diabetes, polycystic ovarian syndrome, metabolic syndrome, low birth weight for gestational age
Prevalence
About 3.5 million people in the UK; 90% are diagnosed with type 2 diabetes
Concern with increasing diabetes rates in children (owing to obesity) and undiagnosed diabetes (estimated at 0.5 million people)
Complications
Microvascular
Diabetic retinopathy
Diabetic nephropathy
Chronic painful neuropathy
Autonomic Neuropathy
Macrovascular
Hypertension
Cardiovascular disease
Cerebrovascular disease
Peripheral arterial disease
Metabolic
Dyslipidaemia
Diabetic ketoacidosis (more often type 1 than type 2 diabetes)
Diabetic hypoglycaemia
Other
Diabetic foot problems
Infection prone
Psychological, Dementia
Reduced life expectancy
Diagnosis
Abnormal blood test
HbA1c ≥ 48 mmol/mol [6.5%]
Random blood glucose >11 mmol/L
Fasting plasma glucose >7 mmol/L (preferred test in people with end-stage chronic kidney disease)
Symptomatic of diabetes:
thirst, polyuria, blurred vision, weight loss, recurrent infections, and tiredness
insulin resistance (for example acanthosis nigricans).
If asymptomatic of DM + 1st abnormal blood test: diagnosis requires at least at least one more interval abnormal blood test (i.e. at least 2 serial abnormal blood tests)
If symptomatic of DM + 1st abnormal blood test : diagnosis established
Type 2 diabetes is more likely if there are no features to suggest an alternative diagnosis (such as Type 1 diabetes, monogenic diabetes or secondary diabetes)
Caution when interpreting HbA1c
HbA1c should NOT be used to diagnose diabetes in:
Children
Pregnancy and <2 months postpartum
Diabetic symptoms <2 months
Acute illness
Secondary diabetic conditions (acute pancreatic damage) or chemically induced diabetes
End-stage chronic kidney disease
HIV infection
HbA1c should be interpreted with caution in people with:
Abnormal haemoglobin
Anaemia
Altered red cell lifespan (such as post splenectomy)
Recent blood transfusion
Management
Ensure that an individual care plan is set up
Offer a structured group education programme: DESMOND (Diabetes Education for Self-Management for Ongoing and Newly Diagnosed) programme, to the person and/or their family/carers.
Manage lifestyle issues, such as diet and exercise (150 minutes (2.5 hours) of moderate intensity physical activity per week).
Diet: plenty of fibre, low-glycaemic-index sources of carbohydrate (such as fruit, vegetables, wholegrain, and pulses), low-fat dairy products, and oily fish.
If the person is overweight, set an initial body weight loss target of 5–10% (smaller weight losses may still be beneficial).
Consider referring the person to a dietitianScreen for complications of type 2 diabetes
At diagnosis, annually thereafter: retinopathy, diabetic foot problems, neuropathy, nephropathy (urine ACR); cardiovascular risk factors
Every 6m measure HBA1c (measures at 3–6-monthly intervals initially, until it is stable on unchanging antidiabetic treatment)Recommend, as 1st line treatment, ACE inhibitor or angiotensin-II receptor antagonist if established diagnosis of hypertension and type 2 diabetes
Do not offer antiplatelet treatment (aspirin or clopidogrel) for the primary prevention of cardiovascular disease (CVD) in adults with type 2 diabetes
Offer atorvastatin 20 mg for primary prevention (if age<84y and QRISK 3 10-year-risk of CVD>10%, and consider if age>84 without QRISK 3 assessment)
Offer atorvastatin 80 mg for secondary prevention (if established CVD, without risk assessment)Managing erectile dysfunction- consider prescribing a phosphodiesterase-5 inhibitor (sildenafil, vardenafil, or tadalafil)
What are the treatment targets for adults with type 2 diabetes?
For people who are managed by lifestyle and diet: 48 mmol/mol (6.5%).
For people who are managed by lifestyle and diet combined with a single drug not associated with hypoglycaemia (such as metformin): 48 mmol/mol (6.5%).
For people who are taking a drug associated with hypoglycaemia (such as a sulphonylurea): 53 mmol/mol (7.0%).
Measure HbA1c levels at 3–6-monthly intervals (tailored to individual needs) until the HbA1c is stable on unchanging treatment, then at 6-monthly intervals.
If HbA1c levels are not adequately controlled by a single drug and rise to 58 mmol/mol (7.5%) or higher: intensify antidiabetic drug treatment.
Consider relaxing the target HbA1c level if:
The person is unlikely to achieve longer-term risk-reduction benefits, for example they have a reduced life expectancy.
Tight blood glucose control poses a high risk of the consequences of hypoglycaemia, for example in people who are at risk of falling, people who have impaired awareness of hypoglycaemia, and people who drive or operate machinery as part of their job.
Intensive management would be inappropriate, for example in a person with significant comorbidities.
Self-monitoring of blood glucose
Do not routinely offer self-monitoring of blood glucose levels for adults with type 2 diabetes.
Advise self-monitoring of blood glucose levels if:
The person is on insulin therapy, or
There is evidence of hypoglycaemic episodes, or
The person is taking a drug that may increase their risk of hypoglycaemia while driving or operating machinery (such as a sulfonylurea), or
The person is pregnant or is planning to become pregnant.
Consider advising short-term self-monitoring of blood glucose levels (and review treatment as necessary):
When starting treatment with corticosteroids, or
To confirm suspected hypoglycaemia.
Antidiabetic drugs
1st line: Metformin
Gradually increase the dose of standard-release metformin over several weeks to minimize the risk of adverse effects, such as gastrointestinal (GI) adverse effects.
If GI adverse effects are intolerable, consider a trial of modified-release metformin.
Monitor renal function before and during treatment with metformin.
2nd line: Dual combination treatment
Metformin plus a gliptin
Metformin plus pioglitazone
Metformin plus a sulfonylurea
Metformin plus an SGLT-2i
3rd line: Triple combination treatment OR Start insulin-based treatment.
Triple combination treatment
Metformin, a gliptin, and a sulfonylurea
Metformin, pioglitazone, and a sulfonylurea
Metformin, (pioglitazone or a sulfonylurea) and SGLT-2i.
(The SGLT-2i dapagliflozin recommended triple therapy combination: metformin + sulfonylurea + dapagliflozin)
Triple combination treatment in specific subgroup population
Metformin, sulfonylurea, glucagon-like peptide-1(GLP-1) mimetic
For adults:
BMI>35 AND specific psychological or other medical problems associated with obesity
BMI<35 but insulin therapy would have significant occupational implications, or weight loss would benefit other significant obesity-related comorbidities.
After 6 months of treatment with a GLP-1 mimetic
GLP-1 mimetic therapy should only be continued if the person has had a beneficial metabolic response (a reduction of at least 11 mmol/mol [1.0%] in HbA1c and a weight loss of at least 3% of initial body weight in 6 months).
What immediate treatment is recommended for adults with type 2 diabetes who have symptomatic hyperglycaemia?
Consider insulin therapy or a sulfonylurea.
Review treatment when blood glucose control has been achieved.
How should I manage an adult with type 2 diabetes during a period of illness?
Consider the need for hospital admission or seeking specialist advice.
Warn the person and/or their family/carers that illness may affect blood glucose control:
Some illnesses (especially if associated with fever) can raise blood glucose levels.
In contrast, illnesses associated with vomiting and diarrhoea (such as gastroenteritis) can lower blood glucose levels, possibly leading to hypoglycaemia (generally defined as blood glucose levels less than 3.5 mmol/L).
Consider the need for self-monitoring of blood glucose levels.
Provide the person with clear individualized oral and written advice ('sick-day rules') and ensure patient has Sick day foods and hydration supplies
'Sick-day rules'
If they are on insulin therapy, they should not stop their treatment.
The dose of insulin may need to be altered during periods of illness;
If self-monitoring of blood glucose levels is indicated:
check every 3–4 hr including through the night, and sometimes every 1–2 hr.
Consider ketone monitoring (blood or urine): check regularly as for blood glucose.If the urine ketone level is greater than 2+,
or blood ketone levels are greater than 3 mmol/L,
the person should contact the GP or diabetes specialist team immediately.Maintain their normal meal pattern (where possible)
Aim to drink at least 3 L of fluid a day to prevent dehydration.
They should seek urgent medical advice if:
They are sick, drowsy, or unable to keep fluids down.
They have persistent vomiting or diarrhoea.
Sick day foods and hydration supplies
Easily digestible food and sugary drinks (to provide energy and to prevent further ketosis).
Oral rehydration salt sachets (to prevent dehydration).
Glucose tablets or oral gel (to prevent hypoglycaemia).
Equipment for self-monitoring of blood glucose and ketones.
Additional supplies of insulin (if the person is on insulin therapy).
A glucagon kit (if appropriate).