Practice EssentialsType 2 diabetes mellitus consists of an array of dysfunctions characterized by hyperglycemia and resulting from the combination of resistance to insulin action, inadequate insulin secretion, and excessive or inappropriate glucagon secretion. See the image below.

Simplified scheme for the pathophysiology of type 2 diabetes mellitus.

See Clinical Findings in Diabetes Mellitus, a Critical Images slideshow, to help identify various cutaneous, ophthalmologic, vascular, and neurologic manifestations of DM.

Essential Update: New Abridged Recommendations for Primary Care Providers

The American Diabetes Association has released condensed recommendations for Standards of Medical Care in Diabetes: Abridged for Primary Care Providers, highlighting recommendations most relevant to primary care. The abridged version focusses particularly on the following aspects:

Prediabetes Self-management education Nutrition Physical activity Smoking cessation Psychosocial care Immunizations Glycemic treatment Therapeutic targets Diagnosis and treatment of vascular complications

Intensification of insulin therapy in type 2 diabetes

The recommendations can be accessed at American Diabetes Association DiabetesPro Professional Resources Online, Clinical Practice Recommendations – 2015.[1]

Signs and symptoms

Many patients with type 2 diabetes are asymptomatic. Clinical manifestations include the following:

Classic symptoms: Polyuria, polydipsia, polyphagia, and weight loss Blurred vision Lower-extremity paresthesias Yeast infections (eg, balanitis in men)

See Presentation for more detail.

Diagnosis

Diagnostic criteria by the American Diabetes Association (ADA) include the following[2]

:

A fasting plasma glucose (FPG) level of 126 mg/dL (7.0 mmol/L) or higher, or A 2-hour plasma glucose level of 200 mg/dL (11.1 mmol/L) or higher during a

75-g oral glucose tolerance test (OGTT), or A random plasma glucose of 200 mg/dL (11.1 mmol/L) or higher in a patient with

classic symptoms of hyperglycemia or hyperglycemic crisis

Whether a hemoglobin A1c (HbA1c) level of 6.5% or higher should be a primary diagnostic criterion or an optional criterion remains a point of controversy.

Indications for diabetes screening in asymptomatic adults includes the following[3, 4] :

Sustained blood pressure >135/80 mm Hg Overweight and 1 or more other risk factors for diabetes (eg, first-degree relative

with diabetes, BP >140/90 mm Hg, and HDL < 35 mg/dL and/or triglyceride level >250 mg/dL)

ADA recommends screening at age 45 years in the absence of the above criteria

See Workup for more detail.

Management

Goals of treatment are as follows:

Microvascular (ie, eye and kidney disease) risk reduction through control of glycemia and blood pressure

Macrovascular (ie, coronary, cerebrovascular, peripheral vascular) risk reduction through control of lipids and hypertension, smoking cessation

Metabolic and neurologic risk reduction through control of glycemia

Recommendations for the treatment of type 2 diabetes mellitus from the European Association for the Study of Diabetes (EASD) and the American Diabetes Association (ADA) place the patient's condition, desires, abilities, and tolerances at the center of the decision-making process.[5, 6, 7]

The EASD/ADA position statement contains 7 key points:

1. Individualized glycemic targets and glucose-lowering therapies2. Diet, exercise, and education as the foundation of the treatment program3. Use of metformin as the optimal first-line drug unless contraindicated4. After metformin, the use of 1 or 2 additional oral or injectable agents, with a goal

of minimizing adverse effects if possible5. Ultimately, insulin therapy alone or with other agents if needed to maintain blood

glucose control6. Where possible, all treatment decisions should involve the patient, with a focus on

patient preferences, needs, and values7. A major focus on comprehensive cardiovascular risk reduction

The 2013 ADA guidelines for SMBG frequency focus on an individual's specific situation rather than quantifying the number of tests that should be done. The recommendations include the following[8, 9] :

Patients on intensive insulin regimens – Perform SMBG at least before meals and snacks, as well as occasionally after meals; at bedtime; before exercise and before critical tasks (eg, driving); when hypoglycemia is suspected; and after treating hypoglycemia until normoglycemia is achieved.

Patients using less frequent insulin injections or noninsulin therapies – Use SMBG results to adjust to food intake, activity, or medications to reach specific treatment goals; clinicians must not only educate these individuals on how to interpret their SMBG data, but they should also reevaluate the ongoing need for and frequency of SMBG at each routine visit.

Approaches to prevention of diabetic complications include the following:

HbA1c every 3-6 months Yearly dilated eye examinations Annual microalbumin checks Foot examinations at each visit Blood pressure < 130/80 mm Hg, lower in diabetic nephropathy Statin therapy to reduce low-density lipoprotein cholesterol