Complications
Your Organisational Guidance
ebpracticenet urges you to prioritise the following organisational guidance:
Diabetes Mellitus Type 2Published by: Domus Medica | SSMGLast published: 2017Diabète sucré de type 2Published by: SSMG | Domus MedicaLast published: 2017Chronic kidney disease occurs in about 40% of patients with type 2 diabetes over time, and diabetes is a leading cause of end-stage renal disease.[166][287] Chronic kidney disease is driven by uncontrolled blood pressure and glucose, and increases the risk of cardiovascular disease at least fourfold. An estimated glomerular filtration rate (eGFR) <60 mL/minute/1.73 m² establishes a diagnosis of chronic kidney disease, and microalbuminuria or albuminuria establishes a diagnosis of nephropathy. Either of these findings should prompt increased efforts to aggressively manage systolic blood pressure, avoid non-steroidal anti-inflammatory drugs, and consider use of antihyperglycaemic drugs with low risk of hypoglycaemia and pronounced renal benefits (especially SGLT2 inhibitors or GLP-1 agonists).[180][306]
Also important are use of an ACE inhibitor or angiotensin-II receptor antagonist, and optimisation of glucose control. When eGFR is lower than 30 mL/minute/1.73m², referral to a nephrologist for expectant management of end-stage renal disease is necessary.
Renal failure predisposes patients to anaemia and hypoglycaemia; in renal failure, insulin doses may need to be reduced.
In a global study, prevalence of diabetic retinopathy in newly diagnosed type 2 diabetes varied from 1.5% to 31%, with higher prevalence observed in developing countries.[307] Risk of vision loss is increased by poor blood pressure and glucose control, and by failure to regularly screen for retinopathy, macular degeneration, glaucoma, and cataracts.[308][309] The risk of all of these eye conditions is increased in diabetes.
Incidence of lower extremity amputation (LEA) is between 2.5 and 4 per 1000 people with diabetes per year, with significant geographic variation in LEA rates within countries.[310] Incidence rates of major LEA, defined as loss of lower limb through or above the ankle, are declining in patients with diabetes; however, there is some evidence that minor LEA (loss of lower limb below the level of the ankle) incidence rates are increasing, with about half being toe or metatarsal amputations.[284]
Risk is aggravated by neuropathy and by peripheral vascular disease, and can be reduced by smoking cessation; aggressive management of glucose, blood pressure, and lipids; use of customised footwear in patients with known neuropathy or foot deformity; and prompt and aggressive management of lower extremity infections.
People with type 2 diabetes have a dementia risk approximately 1.5 to 2.5 times greater than age- and sex-matched individuals without type 2 diabetes.[317][318][319] Findings from the Swedish National Diabetes Register found that the association of type 2 diabetes with dementia varies by dementia subtype. The strongest detrimental association is observed for vascular dementia, but patients with type 2 diabetes with poor glycemic control have an increased risk of developing vascular and non-vascular dementia.[320] A large UK-based cohort study found that higher or unstable HbA1c levels and the presence of diabetic complications in patients with type 2 diabetes are associated with increased dementia risk.[321] A study examining the association between long-term exposure to various levels of HbA1c with dementia showed that dementia risk was greatest among adults with cumulative HbA1c concentrations of 9% or more.[322]
Cardiovascular disease (CVD) and CVD-associated mortality is declining in patients with diabetes, particularly in high-income countries.[284] Adults with type 2 diabetes are twice as likely to die of stroke or myocardial infarction compared with those without diabetes, and they are more than 40 times more likely to die of macrovascular complications than to die of microvascular complications of diabetes.[9][10] To reduce cardiovascular risk, blood pressure, lipids, and tobacco use should be adequately managed. Use of statins, ACE inhibitors, metformin, aspirin, sodium-glucose cotransporter-2 (SGLT2) inhibitors, glucose-like peptide-1 (GLP-1) receptor agonists, and proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors may reduce cardiovascular mortality or all-cause mortality in selected patients with type 2 diabetes. There is increasing evidence that the way in which glucose is managed can have a substantial impact on cardiovascular outcomes. In the ACCORD and ADVANCE randomised trials, near-normal glucose control failed to decrease cardiovascular mortality or all-cause mortality in type 2 diabetes, and in one of those studies, increased all-cause mortality. However, ACCORD and ADVANCE trials did not use the SGLT2 inhibitor empagliflozin, the GLP-1 receptor agonist liraglutide, or PCSK9 inhibitors. Many studies suggest that HbA1c ≥64 mmol/mol (≥8%) increases risk of major cardiovascular events.[144][148]
Increased fatigability may be an early warning sign of progressive cardiovascular disease; clinicians should have a low threshold for cardiac evaluation of any symptoms that are potentially cardiac-related in patients with type 2 diabetes.
Diabetes is a risk factor for CHF, with poor glycaemic control associated with greater risk for the development of CHF and worsening of clinical outcomes for patients with CHF and diabetes.[289] Heart failure occurs in up to 22% of patients with diabetes, and CHF occurs in up to 10% to 15% of patients with diabetes.[290][291] CHF in type 2 diabetes is often related to uncontrolled hypertension, or ischaemic coronary disease, but may also occur as a microvascular complication of diabetes, and as such represents a major cardiovascular complication of diabetes.[290] Heart failure may be the first presentation of cardiovascular disease in many people with diabetes.[290]
The European Society of Cardiology (ESC) recommends SGLT2 inhibitors, beta-blockers, aldosterone antagonists, and the use of either an angiotensin receptor-neprilysin inhibitor (ARNi; e.g., sacubitril/valsartan) or an ACE inhibitor for patients with type 2 diabetes and heart failure with reduced ejection fraction, to reduce the risk of hospitalisation for heart failure and death.[80] Other medicines (e.g., diuretics, digoxin) may be indicated in selected patients.[80]
Must rule out underlying causes such as myocardial infarction, atrial fibrillation, thyroid disorders, anaemia, or structural heart disease.
Related to uncontrolled blood pressure, glucose, and lipids. Lifetime risk is higher in women than in men with diabetes.[292]
Prompt hospitalisation and neurological evaluation, with possible emergency use of tissue plasminogen activator or other therapeutic strategies, may minimise damage and maximise potential for recovery of function.
Hyperglycaemia compromises defence against bacterial infections by several mechanisms including impaired phagocytosis.
Normalisation of blood glucose reduces the risk of infections, especially cystitis, cellulitis, and pneumonia.
Immunisation reduces the risk of serious pneumococcal, Haemophilus influenzae, and influenza infections. Vaccination against COVID-19 is recommended in the UK for people with type 2 diabetes.[293] Patients with type 2 diabetes are at higher risk for severe illness from COVID-19.[294] They are more likely to need intensive care and mechanical ventilation if they develop COVID-19, compared with patients who do not have diabetes, and have a higher case fatality rate and increased odds of in-hospital death with COVID-19.[295][296][297][298] Poor glycaemic control, hypertension, previous stroke, previous heart failure, renal impairment, cancer, body mass index <20 kg/m² or ≥40 kg/m², male sex, older age, non-white ethnicity, and socioeconomic deprivation are associated with increased mortality from COVID-19.[297][299][300] See Coronavirus disease 2019 (COVID-19) (Management).
Aggressive infection-specific therapy and supportive therapy including adequate glucose control are key to successful treatment.
Type 2 diabetes is associated with periodontal disease, but causality is not established. Some studies have suggested a bidirectional relationship between glycaemic control and periodontitis, and a 2022 Cochrane review noted there is moderate-certainty evidence that periodontal treatment using subgingival instrumentation improves glycaemic control in people with both periodontitis and diabetes by a clinically significant amount when compared to no treatment or usual care.[301][302]
Therefore, control of periodontal disease and hyperglycaemia are mutually beneficial and routine preventative dental care is important for people with type 2 diabetes.
NICE recommends that patients should be advised about the raised risk of periodontitis in type 2 diabetes and that its management can improve blood glucose control.[36] Patients should be made aware of the benefit of regular oral health reviews, and those with periodontitis should be offered appropriate dental care.[36]
Hypoglycaemia is the most common and potentially most serious side effect of insulin and/or insulin secretagogues (sulfonylureas or meglitinides), alone or in combination with other drugs.
[ 
]
It can lead to decreased quality of life; severe hypoglycaemia is a medical emergency that can cause confusion, seizures, and coma. Severe (level 3) hypoglycaemia is defined as any low blood glucose level leading to altered mental and/or physical status requiring assistance from another person for recovery.[34] Level 1 hypoglycaemia is defined as ≤3.9 mmol/L (≤70 mg/dL), and level 2 hypoglycaemia is defined as <3.0 mmol/L (<54 mg/dL).[34] Treatment with fast-acting carbohydrate is required when a blood glucose of ≤3.9 mmol/L (≤70 mg/dL) is detected (glucose is preferred), and glucagon should be used if the person is unable or unwilling to consume carbohydrates by mouth.[34] Adjustment of glucose-lowering therapy may be required, and history of hypoglycaemic events should be sought at every clinical encounter (and presence of hypoglycaemic awareness annually) in those at risk of hypoglycaemia to determine the need for treatment plan changes.[34] Low blood sugars are common in patients who are trying to achieve HbA1c <53 mmol/mol (<7%). Hypoglycaemia is usually associated with warning signs, such as rapid heartbeat, perspiration, shakiness, anxiety, confusion, and hunger. Hypoglycaemia unawareness (absence of symptoms during hypoglycaemia), and severe hypoglycaemia, occurs in 1% to 3% of type 2 diabetes patients per year. Older people and those with comorbid heart disease, congestive heart failure, chronic kidney disease, or depression are at substantially increased risk for severe hypoglycaemia.[303] Hypoglycaemia avoidance is important in those with CVD, as hypoglycaemia is associated with increased risk of vascular events.[80]
Patients should be counselled on recognition, prevention, and treatment of hypoglycaemia and should carry with them glucose tablets or comparable fast-acting carbohydrate product. People who drive need to be particularly careful to avoid hypoglycaemia and should be warned of the dangers. Patients using alpha-glucosidase inhibitors must use glucose tablets for hypoglycaemia because absorption of conventional carbohydrates is slowed by the medication.
When glycaemic goals or adherence to treatment plan are difficult to achieve, the presence of depression should be considered. Screening with a validated tool such as the Patient Health Questionnaire (PHQ)-9 may help with identification and diagnosis. The cross-sectional prevalence of depression is 10% to 25% in people with diabetes.[312] Adults with type 2 diabetes diagnosed before age 40 years have excess hospitalisations across their lifespan, which includes a large burden of mental illness in young adulthood.[313]
Obstructive sleep apnoea is common among adults with overweight and obesity, and has been associated with insulin resistance and altered glucose metabolism. Further studies are needed to assess the effect of continuous positive airway pressure on glycaemic control, as results have varied.[314][315][316]
The American Diabetes Association recommends to consider carrying out an assessment of sleep pattern and duration as part of a comprehensive approach to lifestyle and glycaemic control.[34]
Commonly thought of in type 1 diabetes; however, can occur in type 2 diabetes and an unusual type of diabetes known as ketosis-prone diabetes. Infection and poor diabetic medication adherence are the most common reasons for developing DKA, but no precipitating factors may be apparent.[304]
Criteria of DKA is the same, regardless of type of diabetes and is potentially fatal if not properly treated.
Hydration, parenteral insulin therapy, intensive monitoring, and careful management of electrolyte imbalances and acidosis are important for successful therapy.
Occurs most commonly in older people with type 2 diabetes and usually evolves insidiously over days to weeks.[305] Characterised by severe hyperglycaemia, hyperosmolality, and volume depletion, in the absence of severe ketoacidosis.
Hydration, insulin therapy, and careful clinical and laboratory monitoring are the basis of successful therapy.
Diabetic peripheral neuropathy is the most common chronic complication of diabetes, characterised by the presence of peripheral nerve dysfunction, diagnosed after the exclusion of other causes.[311] Pain is the outstanding complaint in most patients, but many patients are completely asymptomatic.
Manifestations of autonomic neuropathy may include: erectile dysfunction, diarrhoea, gastroparesis, or orthostatic hypotension.
For type 2 diabetes the effects of glycaemic control on peripheral or autonomic neuropathy are less clear than for type 1 diabetes. However, some studies in type 2 diabetes have demonstrated a modest slowing of progression without reversal of neuronal loss, with specific glucose lowering strategies potentially having different effects.[34]
Use of this content is subject to our disclaimer