What are the typical symptoms at initial presentation of type 2 diabetes (T2D)?

From the Guidelines

Type 2 diabetes often presents with classic symptoms such as increased thirst, frequent urination, unexplained weight loss, increased hunger, fatigue, blurred vision, slow-healing sores, and areas of darkened skin, although many patients may be asymptomatic at the time of diagnosis, as noted in the most recent guidelines 1.

Symptoms of Type 2 Diabetes

The symptoms of type 2 diabetes develop gradually due to chronically elevated blood glucose levels. When blood sugar rises, the kidneys work harder to filter and absorb the excess glucose, and when they can't keep up, this excess sugar is excreted into the urine, drawing fluid from tissues and triggering thirst. The body's inability to effectively use glucose for energy leads to hunger and fatigue. High glucose levels can also damage small blood vessels in the eyes, causing blurred vision, while compromised circulation and immune function result in poor wound healing and recurrent infections.

Some key points to consider about the presentation of type 2 diabetes include:

• Many people with type 2 diabetes may have the condition for years before diagnosis because symptoms develop slowly and may not be recognized 1.
• The risk of developing type 2 diabetes increases with age, obesity, and lack of physical activity, and it occurs more frequently in certain racial/ethnic subgroups and in individuals with a strong genetic predisposition or family history 1.
• Type 2 diabetes frequently goes undiagnosed for many years because hyperglycemia develops gradually and, at earlier stages, is often not severe enough for the patient to notice the classic diabetes symptoms caused by hyperglycemia 1.
• Approximately one-quarter of people with diabetes in the U.S. and nearly half of Asian and Hispanic Americans with diabetes are undiagnosed, highlighting the importance of screening and early detection 1.

Importance of Early Detection

Early detection and diagnosis of type 2 diabetes are crucial for preventing long-term complications and improving patient outcomes. Screening for prediabetes and type 2 diabetes risk through an informal assessment of risk factors or with an assessment tool is recommended to guide providers on whether performing a diagnostic test is appropriate 1. The American Diabetes Association (ADA) risk test is one such tool that can be used to assess an individual's risk of developing type 2 diabetes.

Given the potential for asymptomatic presentation and the importance of early detection, healthcare providers should prioritize screening for type 2 diabetes in high-risk individuals, as outlined in the latest guidelines 1. This approach can help identify individuals with undiagnosed type 2 diabetes and enable early intervention to prevent or delay the onset of complications.

From the FDA Drug Label

The FDA drug label does not answer the question.

From the Research

Symptoms at First Presentation of Type 2 Diabetes

• The symptoms of type 2 diabetes at first presentation can vary, but typical diabetic symptoms, signs, and complications are common, with 89% of patients presenting with one or more of these hyperglycaemic symptoms and signs 2.
• These symptoms include abnormal thirst, frequent urination, weight loss, genital itching, stomatitis, visual disturbances, fatigue, confusion, and balanitis in men, which are associated with glycaemic level irrespective of age, sex, BMI, blood pressure, complications, and antihypertensive treatment 2.
• The pre-diagnostic duration of hyperglycaemic symptoms and signs is typically short, usually less than 3 months 2.
• Elevated levels of cardiovascular risk factors and longer pre-diagnostic duration of cardiovascular complications may have a central role in early diagnosis of type 2 diabetes 2.

Diagnostic Criteria

• Fasting plasma glucose (FPG) and glycated haemoglobin (HbA1c) are commonly used diagnostic criteria for type 2 diabetes, with FPG ≥ 126 mg/dL and HbA1c ≥ 6.5% being the standard thresholds 3, 4.
• However, using HbA1c alone may not detect all cases of diabetes, with a sensitivity of only 43.3% compared to FPG and 28.1% compared to 2-hour plasma glucose (2hPG) 3.
• Combining FPG and HbA1c may identify more individuals at risk of progression to type 2 diabetes, with a higher cumulative incidence of diabetes in subjects with impaired fasting glucose (IFG) and HbA1c 5.5-6.4% 5.

Comparison of Diagnostic Criteria

• FPG and HbA1c have different diagnostic accuracies, with FPG being more sensitive in detecting diabetes, especially in older, leaner, and female patients 3, 4.
• Serial FPG testing may lead to earlier diagnosis of type 2 diabetes than HbA1c, with average FPG levels being higher in patients who met the criterion for T2DM with FPG (>7 mM) or HbA1c (>6.5%), but not both 6.
• The combination of FPG and HbA1c identifies individuals who are at risk of progression to type 2 diabetes, with a hazard ratio for diabetes adjusted for possible confounders being 7.4,14.4, and 38.4 for those with normal fasting glucose (NFG) and HbA1c 5.5-6.4%, IFG and HbA1c < 5.5%, and IFG and HbA1c 5.5-6.4%, respectively 5.