Note from the Scottish Intercollegiate Guidelines Network (SIGN) and National Guideline Clearinghouse (NGC): In addition to these evidence-based recommendations, the guideline development group also identifies points of best clinical practice in the full-text guideline document.
The grades of recommendations (A–D) and levels of evidence (1++, 1+, 1-, 2++, 2+, 2-, 3, 4) are defined at the end of the "Major Recommendations" field.
Delivery of Lifestyle Interventions
A - People with diabetes should be offered lifestyle interventions based on a valid theoretical framework.
B - Computer-assisted education packages and telephone prompting should be considered as part of a multidisciplinary lifestyle intervention programme.
B - Healthcare professionals should receive training in patient-centred interventions in diabetes.
A - Adults with type 1 diabetes experiencing problems with hypoglycaemia or who fail to achieve glycaemic targets should have access to structured education programmes based upon adult learning theories.
B - Children and adolescents should have access to programmes of structured education which have a basis in enhancing problem solving skills.
A - Adults with type 2 diabetes should have access to structured education programmes based upon adult learning theories.
Self-Monitoring of Glycaemia
B - Self-monitoring of blood glucose (SMBG) is recommended for patients with type 1 or type 2 diabetes who are using insulin where patients have been educated in appropriate alterations in insulin dose.
B - Routine self-monitoring of blood glucose in people with type 2 diabetes who are using oral glucose-lowering drugs (with the exception of sulphonylureas) is not recommended.
B - Routine self-monitoring of urine glucose is not recommended in patients with type 2 diabetes.
B - All people who smoke should be advised to stop and offered support to help facilitate this in order to minimise cardiovascular and general health risks.
A - Healthcare professionals involved in caring for people with diabetes should advise them not to smoke.
B - Intensive management plus pharmacological therapies should be offered to patients with diabetes who wish to stop smoking.
B - Healthcare professionals should continue to monitor smoking status in all patient groups.
Exercise and Physical Activity
B - All people should be advised to increase their level of physical activity to achieve current physical activity recommendations and be supported to maintain this level across the lifespan.
A - People with type 2 diabetes should be encouraged to participate in physical activity or structured exercise to improve glycaemic control and cardiovascular risk factors.
B - People with type 1 diabetes should be encouraged to participate in physical activity or structured exercise to improve cardiovascular risk factors.
D - Exercise and physical activity (involving aerobic and/or resistance exercise) should be performed on a regular basis.
D - Advice about exercise and physical activity should be individually tailored and diabetes specific and should include implications for glucose management and foot care.
C - Individualised advice on avoiding hypoglycaemia when exercising by adjustment of carbohydrate intake, reduction of insulin dose, and choice of injection site, should be given to patients taking insulin.
D - Patients with existing complications of diabetes should seek medical review before embarking on exercise programmes.
D - A gradual introduction and initial low intensity of physical activity with slow progressions in volume and intensity should be recommended for sedentary people with diabetes.
Weight Management in Type 2 Diabetes
A - Obese adults with type 2 diabetes should be offered individualised interventions to encourage weight loss (including lifestyle, pharmacological or surgical interventions) in order to improve metabolic control.
B - People with type 2 diabetes can be given dietary choices for achieving weight loss that may also improve glycaemic control. Options include simple caloric restriction, reducing fat intake, consumption of carbohydrates with low rather than high glycaemic index, and restricting the total amount of dietary carbohydrate (a minimum of 50 g per day appears safe for up to six months).
B - Dietary supplementation with omega-3 polyunsaturated fatty acid (PUFA) is not generally recommended in people with type 2 diabetes.
B - Vitamin E supplementation 500 mg per day is not recommended in people with type 2 diabetes.
B - Overweight individuals and those at high risk of developing diabetes should be encouraged to reduce this risk by lifestyle changes including weight management and physical activity.
B - Clinical interventions aimed at dietary change are more likely to be successful if a psychological approach based on a theoretical model is included.
B - People with diabetes can take alcohol in moderation as part of a healthy lifestyle but should aim to keep within the target consumption recommended for people without diabetes.
The Influence of Psychosocial Factors on Diabetes Control
B - Regular assessment of a broad range of psychological and behavioural problems in children and adults with type 1 diabetes is recommended.
- In children this should include eating disorders, behavioural, emotional and family functioning problems.
- In adults this should include anxiety, depression and eating disorders.
The Effect of Psychological Interventions on Diabetes Outcomes
A - Children and adults with type 1 and type 2 diabetes should be offered psychological interventions (including motivational interviewing, goal setting skills and cognitive behavioural therapy [CBT]) to improve glycaemic control in the short and medium term.
Management of Type 1 Diabetes
Diagnosis and Epidemiology
B - Screening for pre-type 1 diabetes is not recommended in either the general population or in high risk children and young people.
Initiating Therapy at Diagnosis
C - A home-based programme for initial management and education of children with diabetes and their families is an appropriate alternative to a hospital-based programme.
B - Intensive insulin therapy should be delivered as part of a comprehensive support package.
B - An intensified treatment regimen for adults with type 1 diabetes should include either regular human or rapid-acting insulin analogues.
B - Basal insulin analogues are recommended in adults with type 1 diabetes who are experiencing severe or nocturnal hypoglycaemia and who are using an intensified insulin regimen. Adults with type 1 diabetes who are not experiencing severe or nocturnal hypoglycaemia may use basal analogues or neutral protamine Hagedorm (NPH) insulin.
B - Children and adolescents may use either insulin analogues (rapid-acting and basal), regular human insulin and neutral protamine Hagedorm preparations or an appropriate combination of these.
C - The insulin regimen should be tailored to the individual child to achieve the best possible glycaemic control without disabling hypoglycaemia.
A - Continuous subcutaneous insulin infusion (CSII) therapy is associated with modest improvements in glycaemic control and should be considered for patients unable to achieve their glycaemic targets.
B - CSII therapy should be considered in patients who experience recurring episodes of severe hypoglycaemia.
B - Dietary advice as part of a comprehensive management plan is recommended to improve glycaemic control.
Quality of Life
B - Patients and healthcare professionals should make every effort to avoid severe hypoglycaemia, particularly in those who are newly diagnosed.
Long Term Complications and Screening
A - To reduce the risk of long term microvascular complications, the target for all young people with diabetes is the optimising of glycaemic control towards a normal level.
C - Patients with cystic fibrosis should be screened annually for diabetes from 10 years of age.
C - Young people with diabetes should be screened for thyroid and coeliac disease at onset of diabetes and at intervals throughout their lives.
Pharmacological Management of Glycaemic Control in People with Type 2 Diabetes
Targets for Glycaemic Control
A - A glycosylated haemoglobin (HbA1c) target of 7.0% (53 mmol/mol) among people with type 2 diabetes is reasonable to reduce risk of microvascular disease and macrovascular disease. A target of 6.5% (48 mmol/mol) may be appropriate at diagnosis. Targets should be set for individuals in order to balance benefits with harms, in particular hypoglycaemia and weight gain.
A - Metformin should be considered as the first line oral treatment option for overweight patients with type 2 diabetes.
A - Sulphonylureas should be considered as first line oral agents in patients who are not overweight, who are intolerant of, or have contraindications to, metformin.
A - Pioglitazone can be added to metformin and sulphonylurea therapy, or substituted for either in cases of intolerance.
A - Pioglitazone should not be used in patients with heart failure.
B - The risk of fracture should be considered in the long term care of female patients treated with pioglitazone.
A - Rosiglitazone can be added to metformin and sulphonylurea combination therapy, or substituted for either in cases of intolerance.
A - Rosiglitazone should not be used in patients with heart failure.
B - The risk of fracture should be considered in the long term care of female patients treated with rosiglitazone.
Dipeptidyl Peptidase-4 (DPP-4) Inhibitors
A - DPP-4 inhibitors may be used to improve blood glucose control in people with type 2 diabetes.
B - Alpha-glucosidase inhibitors can be used as monotherapy for the treatment of patients with type 2 diabetes if tolerated.
Glucagon Like Peptide-1 (GLP-1) Agonists
A - GLP-1 agonists (exenatide or liraglutide) may be used to improve glycaemic control in obese adults (body mass index [BMI] ≥30 kg/m2) with type 2 diabetes who are already prescribed metformin and/or sulphonylureas. A GLP-1 agonist will usually be added as a third line agent in those who do not reach target glycaemia on dual therapy with metformin and sulphonylurea (as an alternative to adding insulin therapy).
A - Liraglutide may be used as a third line agent to further improve glycaemic control in obese adults (BMI ≥30 kg/m2) with type 2 diabetes who are already prescribed metformin and a thiazolidinedione and who do not reach target glycaemia.
A - Oral metformin and sulphonylurea therapy should be continued when insulin therapy is initiated to maintain or improve glycaemic control.
A - Once daily bedtime neutral protamine Hagedorm insulin should be used when adding insulin to metformin and/or sulphonylurea therapy. Basal insulin analogues should be considered if there are concerns regarding hypoglycaemia risk.
A - When commencing insulin therapy, bedtime basal insulin should be initiated and the dose titrated against morning (fasting) glucose. If the HbA1c level does not reach target then addition of prandial insulin should be considered.
A - Soluble human insulin or rapid-acting insulin analogues can be used when intensifying insulin regimens to improve or maintain glycaemic control.
Management of Diabetes in Pregnancy
C - Pre-pregnancy care provided by a multidisciplinary team is strongly recommended for women with diabetes.
C - Pre-pregnancy glycaemic control should be maintained as close to the non-diabetic range as possible, taking into account risk of maternal hypoglycaemia.
B - All women with diabetes should be prescribed high dose pre-pregnancy folate supplementation, continuing up to 12 weeks gestation.
B - Women with diabetes initially treated in early pregnancy with metformin or sulphonylureas should be advised that these medications do not appear to carry additional risk of teratogenesis or early pregnancy loss.
D - Dietetic advice should be available in all diabetic antenatal clinics.
Optimisation of Glycaemic Control
D - All women with pre-gestational diabetes should be encouraged to achieve excellent glycaemic control.
C - Postprandial glucose monitoring should be carried out in pregnant women with gestational diabetes and may be considered in pregnant women with type 1 or 2 diabetes.
B - Continuous glucose monitoring may be considered in women with type 1 and type 2 diabetes.
B - Rapid-acting insulin analogues (lispro and aspart) appear safe in pregnancy and may be considered in individual patients where hypoglycaemia is problematic.
Complications during Pregnancy
C - Examination of the retina prior to conception and during each trimester is advised in women with type 1 and type 2 diabetes. More frequent assessment may be required in those with poor glycaemic control, hypertension or pre-existing retinopathy.
C - Early referral of pregnant women with referable retinopathy to an ophthalmologist is recommended due to the potential for rapid development of neovascularisation.
C - Women should be reassured that tight glycemic control during and immediately after pregnancy can effectively reduce the long term risk of retinopathy.
B - All women should be offered scanning to include a detailed anomaly scan including four chamber cardiac view and outflow tracts between 20 and 22 weeks.
C - Where intrauterine growth restriction (IUGR) is suspected, regular monitoring including growth scans and umbilical artery Doppler should be carried out.
A - A suitable programme to detect and treat gestational diabetes should be offered to all women in pregnancy.
A - Pregnant women with gestational diabetes mellitus (GDM) should be offered dietary advice and blood glucose monitoring and be treated with glucose-lowering therapy depending on fasting and postprandial targets.
B - Metformin or glibenclamide may be considered as initial pharmacological, glucose-lowering treatment in women with gestational diabetes.
Infants of Mothers with Diabetes
B - Breastfeeding is recommended for infants of mothers with diabetes, but mothers should be supported in the feeding method of their choice.
Follow Up of Women with Gestational Diabetes Mellitus
C - Women who have developed gestational diabetes mellitus should be given diet, weight control and exercise advice.
C - Women who have developed gestational diabetes mellitus should be reminded of the need for pre-conception counselling and appropriate testing to detect progression to type 2 diabetes.
Management of Diabetic Cardiovascular Disease
Primary Prevention of Coronary Heart Disease
A - Hypertension in people with diabetes should be treated aggressively with lifestyle modification and drug therapy.
A - Target diastolic blood pressure in people with diabetes is ≤80 mm Hg.
D - Target systolic blood pressure in people with diabetes is <130 mm Hg.
A - Patients with diabetes requiring antihypertensive treatment should be commenced on:
- An angiotensin converting enzyme (ACE) inhibitor (angiotensin-II receptor blocker [ARB] if ACE inhibitor intolerant), or
- A calcium channel blocker, or
- A thiazide diuretic
A - Beta-blockers and alpha blockers should not normally be used in the initial management of blood pressure in patients with diabetes.
A - Low-dose aspirin is not recommended for primary prevention of vascular disease in patients with diabetes.
A - Lipid-lowering drug therapy with simvastatin 40 mg or atorvastatin 10 mg is recommended for primary prevention in patients with type 2 diabetes aged >40 years regardless of baseline cholesterol.
B - Lipid-lowering drug therapy with simvastatin 40 mg should be considered for primary prevention in patients with type 1 diabetes aged >40 years.
Management of Patients with Diabetes and Acute Coronary Syndromes
B - Patients with clinical myocardial infarction and diabetes mellitus or marked hyperglycaemia (>11.0 mmol/l) should have immediate intensive blood glucose control. This should be continued for at least 24 hours.
A - Patients with an ST elevation acute coronary syndrome should be treated immediately with primary percutaneous coronary intervention.
D - When primary percutaneous coronary intervention cannot be provided within 90 minutes of diagnosis, patients with an ST elevation acute coronary syndrome should receive immediate thrombolytic therapy.
A - Aspirin (75 mg per day) should be given routinely and continued long term in patients with diabetes and coronary heart disease.
B - In addition to long term aspirin, clopidogrel therapy should be continued for three months in patients with non-ST elevation acute coronary syndromes.
A - In addition to long term aspirin, clopidogrel therapy should be continued for up to four weeks in patients with ST elevation acute coronary syndromes.
A - Patients with clinical myocardial infarction should be maintained on long term beta-blocker therapy.
A - Patients with clinical myocardial infarction should be commenced on long term ACE inhibitor therapy within the first 36 hours.
A - Intensive lipid-lowering therapy with atorvastatin 80 mg should be considered for patients with diabetes and acute coronary syndromes, objective evidence of coronary heart disease on angiography or following coronary revascularisation procedures.
B - Fibrate treatment can be considered in patients who are intolerant of statins.
Management of Patients with Diabetes and Heart Failure
A - Angiotensin converting enzyme inhibitors should be considered in patients with all New York Heart Association (NYHA) functional classes of heart failure due to left ventricular systolic dysfunction.
A - All patients with heart failure due to left ventricular systolic dysfunction of all NYHA functional classes should be started on beta-blocker therapy as soon as their condition is stable (unless contraindicated by a history of asthma, heart block or symptomatic hypotension).
Management of Patients with Diabetes and Stable Angina
A - All patients with stable angina due to atherosclerotic disease should receive long term standard aspirin and statin therapy.
A - All patients with stable angina should be considered for treatment with ACE inhibitors.
B - For patients with diabetes and multivessel disease, coronary artery bypass grafting (CABG) with use of the internal mammary arteries is preferred over percutaneous transluminal coronary angioplasty (PTCA).
A - Patients with diabetes undergoing angioplasty should be treated with stents where feasible, and receive adjunctive therapy with a platelet glycoprotein IIb/IIa receptor antagonist.
A - In patients with diabetes, drug-eluting stents (DES) are recommended as opposed to bare metal stents (BMS) in stable coronary heart disease or non-ST elevation myocardial infarction to reduce in-stent re-stenosis and target lesion revascularisation.
Management of Kidney Disease in Diabetes
Screening for Kidney Disease in Diabetes
B - Albumin/creatinine ratio (ACR) should be used to screen for diabetic kidney disease.
C - Young people with diabetes should have ACR tested annually from the age of 12 years.
Prevention and Treatment of Kidney Disease in Diabetes
A - Intensive glycaemic control in people with type 1 and 2 diabetes should be maintained to reduce the risk of developing diabetic kidney disease.
A - Reducing proteinuria should be a treatment target regardless of baseline urinary protein excretion. However, patients with higher degrees of proteinuria benefit more. There should be no lower target as the greater the reduction from baseline urinary protein excretion, the greater the effect on slowing the rate of loss of glomerular filtration rate (GFR).
A - In people with diabetes and kidney disease, blood pressure should be reduced to the lowest achievable level to slow the rate of decline of glomerular filtration rate and reduce proteinuria.
A - People with type 1 diabetes and microalbuminuria should be treated with an ACE inhibitor irrespective of blood pressure.
A - People with type 2 diabetes and microalbuminuria should be treated with an ACE inhibitor or an angiotensin-II receptor blocker irrespective of blood pressure.
A - ACE inhibitors and/or angiotensin-II receptor blockers should be used as agents of choice in patients with chronic kidney disease and proteinuria (≥0.5 g/day, approximately equivalent to a protein/creatinine ratio of 50 mg/mmol) to reduce the rate of progression of chronic kidney disease.
A - Dietary protein restrictions (<0.8 g/kg/day) are not recommended in patients with early stages of chronic kidney disease (stages 1-3).
B - People with diabetes and microalbuminuria should be treated with a multifactorial intervention approach.
Management of Complications
D - Patients with diabetes and chronic kidney disease (CKD) stage 3-5 should have their haemoglobin checked at least annually.
A - Erythropoiesis stimulating agents should be considered in all patients with anaemia of chronic kidney disease, including those with diabetic kidney disease.
Models of Care
D - Individuals with diabetes and mild to moderate CKD should be managed in a setting that can provide appropriate investigation, monitoring and intensive clinical management.
Prevention of Visual Impairment
Risk Identification and Prevention
B - Patients with multiple risk factors should be considered at high risk of developing diabetic retinal disease.
A - Good glycaemic control (HbA1c ideally around 7% or 53 mmol/mol) and blood pressure control (<130/80 mm Hg) should be maintained to prevent onset and progression of diabetic eye disease.
B - Laser photocoagulation, if required, should be completed before any rapid improvements in glycaemic control are achieved.
B - Systematic screening for diabetic retinal disease should be provided for all people with diabetes.
C - Patients with type 1 diabetes should be screened from age 12 years.
A - Patients with type 2 diabetes should be screened from diagnosis.
- Patients with diabetes with no diabetic retinopathy could be screened every two years.
- All others should be screened at least annually.
C - Retinal photography or slit lamp biomicroscopy used by trained individuals should be used in a programme of systematic screening for diabetic retinopathy.
Either good quality 7-field stereoscopic photography or slit lamp biomicroscopy (both dilated) carried out by an appropriately experienced ophthalmologist should be used to investigate:
- Clinically significant macular oedema
- Proliferative diabetic retinopathy and severe non-proliferative diabetic retinopathy.
C - Dilated direct ophthalmoscopy should only be used opportunistically.
D - Screening modalities should aim to detect sight-threatening retinal disease with a sensitivity ≥80% and specificity ≥95%.
B - Patients with ungradeable retinal photographs should receive slit lamp and indirect ophthalmoscopy examination where possible.
D - Screening should be performed at a site convenient to patients.
C - Retinal photographs should be graded using digital images by an appropriately trained grader to facilitate quality assurance.
D - All graders should have 500 retinal photographs rechecked for quality assurance each year.
B - Either one field 45-50° retinal photography, or multiple field photography can be used for screening purposes.
B - Automated grading may be used for distinguishing no retinopathy from any retinopathy in a screening programme providing validated software is used.
- All people with type 1 or type 2 diabetes with new vessels at the disc or iris should receive laser photocoagulation.
- Laser photocoagulation should also be provided for patients with new vessels elsewhere with vitreous haemorrhage.
- All people with type 2 diabetes and new vessels elsewhere should receive laser photocoagulation.
D - All people with type 1 diabetes with new vessels elsewhere should receive laser photocoagulation.
A - Patients with severe or very severe non-proliferative diabetic retinopathy should receive close follow up or laser photocoagulation.
A - Modified Early Treatment Diabetic Retinopathy Study (ETDRS) grid laser photocoagulation should be used for patients with clinically significant macular oedema in the absence of significant macular ischaemia.
B - Patients with type 1 diabetes and persistent vitreous haemorrhage should be referred for early vitrectomy.
B - Vitrectomy should be performed in patients with tractional retinal detachment threatening the macula and should be considered in patients with severe fibrovascular proliferation.
B - Cataract extraction should not be delayed in patients with diabetes.
C - Cataract extraction is advised when sight-threatening retinopathy cannot be excluded.
C - When cataract extraction is planned in the context of advanced disease, which is not stabilised prior to surgery, the risk of progression and the need for close postoperative review should be fully discussed with the patient.
D - Community support, maximising disability benefits, low vision aids and training in their use should be provided to people with diabetes and visual impairment.
Management of Diabetic Foot Disease
B - All patients with diabetes should be screened to assess their risk of developing a foot ulcer.
B - Foot care education is recommended as part of a multidisciplinary approach in all patients with diabetes.
B - Patients with diabetic foot disease should be advised to wear running-style, cushion-soled trainers rather than ordinary shoes.
B - Custom-built footwear or orthotic insoles should be used to reduce callus severity and ulcer recurrence.
Management of Active Foot Disease
C - Patients with active diabetic foot disease should be referred to a multidisciplinary diabetic foot care service.
B - Patients who have unilateral plantar ulcers should be assessed for treatment using total contact casting to optimise the healing rate of ulcers.
B - Prefabricated walkers can be used as an alternative if they are rendered irremovable.
B - Negative pressure wound therapy should be considered in patients with active diabetic foot ulcers or postoperative wounds.
B - All patients with critical limb ischaemia, including rest pain, ulceration and tissue loss, should be considered for arterial reconstruction.
- Diagnosis of Charcot neuroarthropathy of the foot should be made by clinical examination.
- Post-diagnosis thermography can be used to monitor disease activity.
D - Total contact casting and non-weight bearing are effective treatments for patients with acute Charcot neuroarthropathy of the foot.
Painful Diabetic Neuropathy
A - Antidepressants, including tricyclics, duloxetine and venlafaxine should be considered for the treatment of patients with painful diabetic peripheral neuropathy (DPN).
A - Anticonvulsants, including pregabalin and gabapentin, should be considered for the treatment of patients with painful DPN.
B - Opiate analgesia in combination with gabapentin should be considered for the treatment of patients with painful DPN which cannot be controlled with monotherapy.
Grades of Recommendation
A: At least one meta-analysis, systematic review, or randomized controlled trial (RCT) rated as 1++, and directly applicable to the target population; or
A body of evidence consisting principally of studies rated as 1+, directly applicable to the target population, and demonstrating overall consistency of results
B: A body of evidence including studies rated as 2++, directly applicable to the target population, and demonstrating overall consistency of results; or
Extrapolated evidence from studies rated as 1++ or 1+
C: A body of evidence including studies rated as 2+, directly applicable to the target population and demonstrating overall consistency of results; or
Extrapolated evidence from studies rated as 2++
D: Evidence level 3 or 4; or
Extrapolated evidence from studies rated as 2+
Levels of Evidence
1++: High quality meta-analyses, systematic reviews of RCTs, or RCTs with a very low risk of bias
1+: Well-conducted meta-analyses, systematic reviews, or RCTs with a low risk of bias
1-: Meta-analyses, systematic reviews, or RCTs with a high risk of bias
2++: High quality systematic reviews of case control or cohort studies
High quality case control or cohort studies with a very low risk of confounding or bias and a high probability that the relationship is causal
2+: Well conducted case control or cohort studies with a low risk of confounding or bias and a moderate probability that the relationship is causal
2-: Case control or cohort studies with a high risk of confounding or bias and a significant risk that the relationship is not causal
3: Non-analytic studies, e.g., case reports, case series
4: Expert opinion