Prevention and Management of Diabetic Complications
Physician skills in prevention and management of complications of diabetes are paramount. The goal is to reduce morbidity and mortality and to reduce the direct and indirect cost on individuals, their families, and to local, national, and global resources.
Cardiovascular Disease
The major cause of mortality in diabetic patients is cardiovascular disease. It is also the major cause of morbidity, and direct and indirect costs. Type 2 diabetes is an independent risk factor for macrovascular disease, and its common co-existing conditions in metabolic syndrome are also risk factors. Physicians should be aware of the signs and symptoms of cardiovascular disease and should make every effort along with the patient in reducing these risk factors.
Hypertension
Screening and Diagnosis
Blood pressure should be taken on diabetic patients at every clinic visit. Patients with a systolic blood pressure ≥130 mmHg or a diastolic blood pressure ≥80 mmHg should have their blood pressure checked on a different day to confirm the diagnosis of prehypertension or hypertension.
Goals Blood Pressure in Diabetes
Goal blood pressure for diabetic patients is lower than that of the general population. In diabetics, the systolic blood pressure (SBP) should be <130 mmHg and (DBP) diastolic blood pressure <80 mmHg.
Treatment
- Diabetic patients with frank hypertension (SBP ≥140 or DBP ≥90) should be on drug therapy along with lifestyle modifications (medical nutritional therapy and physical exercise).
- Diabetic patients with pre-hypertension (SBP of 130 – 139 or a DBP 80 -89) should receive 3 months of lifestyle modifications and if not goal BP not achieved then a renin-angiotensin system blocker should be initiated (ACE inhibitor or Angiotensin Receptor Blocker).
- All diabetics with hypertension should be on a regimen that includes an ACE inhibitor or ARB because of demonstrated renal protection in these patients. Additional medications that can be added if BP is not optimized are diuretics, beta-blockers, and calcium channel blockers). Most patients with hypertension require more than one medication to optimize the blood pressure.
- In type 2 diabetic patients with hypertension and microalbuminuria, ACE inhibitors and ARBs have been shown to delay nephropathy. In type 2 diabetic patients with hypertension and macroalbuminuria, ARBS have been shown to delay nephropathy. ACE inhibitors and ARBs are contraindicated in pregnancy.
- Orthostatic blood pressure measurements should be taken in patients with diabetes and hypertension to assess for autonomic dysfunction.
Hyperlipidemia
Screening
Patients with type 2 diabetes have a higher prevalence of dyslipidemias. In adult diabetic patients, screening for lipid disorder is recommended annually or more often to achieve goals. In patients with low risk lipid values (LDL<100, HDL >50, triglycerides <150), testing may be repeated every other year.
Goals and Treatment
The lipid goal depends on whether the diabetic patient has “overt” cardiovascular disease. All patients should begin with lifestyle modifications.
In patients WITHOUT cardiovascular disease:
- Primary goal is LDL <100.
- If over age 40, statin should be initiated to reduce LDL by 30-40% regardless of the patient’s LDL baseline.
- If under age 40 but at increased risk of cardiovascular risk factors who are not at lipid goals with lifestyle modifications alone should consider pharmacologic therapy.
In patients WITH cardiovascular disease:
- All patients should be treated with a statin to achieve an LDL reduction of 30-40% regardless of baseline.
- A new option is to reduce the LDL <70 with high dose statins if necessary.
All diabetic patients should aim to decrease their triglycerides below 150, and men should increase their HDL ≥ 40 and women the HDL ≥ 50. Fibrates may be a good drug option.
Combination therapies may be necessary but have not been shown to decrease cardiovascular disease at this time.
Antiplatelet Agents
Recommendations from the ADA
- Use aspirin therapy (75–162 mg/day) as a primary prevention strategy in those with type 2 diabetes at increased cardiovascular risk, including those who are >40 years of age or who have additional risk factors (family history of CVD, hypertension, smoking, dyslipidemia, or albuminuria).
- Use aspirin therapy (75–162 mg/day) as a secondary prevention strategy in those with diabetes with a history of CVD.
- Consider aspirin therapy in people between the age of 30 and 40 years, particularly in the presence of other cardiovascular risk factors. People <30 years have not been studied. Aspirin therapy should not be recommended for patients under the age of 21 years because of the increased risk of Reye’s syndrome.
- Combination therapy using other antiplatelet agents such as clopidrogel in addition to aspirin should be used in patients with severe and progressive CVD.
- Other antiplatelet agents may be a reasonable alternative for high-risk patients with aspirin allergy, bleeding tendency, receiving anticoagulant therapy, recent gastrointestinal bleeding, and clinically active hepatic disease who are not candidates for aspirin therapy.
Smoking Cessation
All patients should be advised not to smoke and counseling in smoking cessation and treatment should be integrated into all diabetes care visits.
Coronary Heart Disease Screening and Treatment
Recommendations from the ADA
- In patients >55 years of age, with or without hypertension but with another cardiovascular risk factor (history of CVD, dyslipidemia, microalbuminuria, or smoking), an ACE inhibitor (if not contraindicated) should be considered to reduce the risk of cardiovascular events.
- In patients with a prior myocardial infarction or in patients undergoing major surgery, β-blockers, in addition, should be considered to reduce mortality.
- In asymptomatic patients, consider a risk factor evaluation to stratify patients by 10-year risk and treat risk factors accordingly.
In patients with treated CHF, metformin use is contraindicated. The thiazolidinediones (TZDs) are associated with fluid retention, and their use can be complicated by the development of CHF. Caution in prescribing TZDs in the setting of known CHF or other heart diseases, as well as in patients with preexisting edema or concurrent insulin therapy, is required.
Nephropathy Screening and Treatment
General Recommendations
Goals
The goal of nephropathy screening and treatment is to reduce the risk and slow the progress of nephropathy by optimizing the glucose control and blood pressure control. In those with any degree of chronic kidney disease, protein intake should be reduced to recommended daily allowance of 0.8 g / kg.
Screening
All type 2 diabetes patients should be screened annually for urine microalbumin starting at diagnosis. Serum creatinine should be measured annually to estimate the glomerular filteration rate in all patients with diabetes regardless of microalbuminuria. Serum creatinine should not be used alone to measure renal function but used to measure the GFR and stage the true renal function or dysfunction.
Treatment
Which of the following treatments have controlled trials shown to be beneficial for persons with type 2 diabetes and early nephropathy?
The correct answer is B. Tight blood pressure control and angiotensin-converting enzyme inhibitors have controlled trials shown to be beneficial for persons with type 2 diabetes and early nephropathy.
- In type 2 diabetic patients with hypertension and microalbuminuria, ACE inhibitors and ARBs have been shown to delay progression to macroalbuminuria. In type 2 diabetic patients with hypertension and macroalbuminuria, ARBS have been shown to delay nephropathy. ACE inhibitors and ARBs are contraindicated in pregnancy. The ADA recommends continued surveillance of urine microalbumin / protein to assess therapy response and renal disease progression.
- The presence of nephropathy should initiate protein restriction to ≤0.8 gm/kg.
- Dihydropyridine-sensitive calcium channel blockers are not effective as initial therapy to slow progression of nephropathy and should only be used as an adjunct to an ACE inhibitor or ARB to lower blood pressure.
- If ACE inhibitors, ARBs, or diuretics are used, it is recommended to check serum potassium levels.
- Consider referral to a renal specialist when the GFR falls below <60 ml/min per 1.73m² or if management of hypertension or hyperkalemia becomes difficult.
More information on managing diabetic renal nephropathy can be found in the library.
Retinopathy Screening and Treatment
General Recommendations
Glycemic control can reduce the risk and progression of diabetic retinopathy. Optimal blood pressure control can also reduce the risk of diabetic retinopathy. Aspirin plays no role in preventing or exacerbating diabetic retinopathy.
Screening
All patients should have a comprehensive ophthalmologic examination soon after the diagnosis of diabetes is made. Type 2 diabetics should have repeat annual exams. Screening can occur less often if the exam is normal or more often if retinopathy is found. The presence of retinopathy is related to the duration of the diabetes.
Non-proliferative diabetic retinopathy
Proliferative diabetic retinopathy
There is more information on diabetes retinopathy management in the library.
Neuropathy Screening and Treatment
Screening and Diagnosis: Diabetic Peripheral Neuropathy
All patients should be screened for distal symmetric polyneuropathy (DPN) at diagnosis and at least annually and every year thereafter. The DPN screening test can be be done in the primary care clinical setting using pinprick sensation, temperature, vibration perception and ankle reflex testing. This can be accomplished with a 128-Hz tuning fork, a reflex hammer, and a 10-g monofilament test. The monofilament pressure sensation is best at the dorsal surface of both great toes proximal to the nail beds. The combination of more than one test has a sensitivity of more than >87%. More than two of these tests should occur annually. Once the diagnosis of DPN is established, specialized foot care is critical in preventing the risk of amputation. Insensitive feet should be inspected every 3 – 6 months, and patients should be taught in rigorous self foot care.
Symptomatic treatment of DPN begins with optimizing glucose control. Are you getting the idea? Studies have found that DPN improves significantly with avoiding blood glucose extremes and optimization of glucose levels. DPN pain manifestations can be managed with tricyclic drugs, gabapentin, 5-hydroxytryptamine, and norepinephrine reuptake inhibitors.
Diabetic Autonomic Neuropathy
Major clinic manifestations of diabetic autonomic neuropathy are resting tachycardia, exercise intolerance, orthostatic hypotension, constipation, gastroparesis, erectile dysfunction, pseudomotor dysfunction, impaired neurovascular function, hypoglycemic autonomic failure, and “brittle diabetes”. Assessment of autonomic dysfunction should occur at initial diagnosis of type 2 diabetes.
Treatment of diabetic autonomic neuropathy includes metoclopramide for gastroparesis and the use of bladder and erectile dysfunction medications.
Diabetic Foot Care
Recommendations from the ADA
A comprehensive foot examination should be performed and patients should be provided foot self care education annually to identify risk factors predictive of ulcers and amputations. The foot examination can be accomplished in a primary care setting and should include the use of a monofilament, tuning fork, palpation, and a visual examination. A multidisciplinary approach is recommended for individuals with foot ulcers and high-risk feet, especially those with a history of prior ulcer or amputation. Refer patients who smoke or with prior lower-extremity complications to foot care specialists for ongoing preventive care and life-long surveillance. Initial screening for peripheral arterial disease (PAD) should include a history for claudication and an assessment of the pedal pulses. Consider obtaining an ankle-brachial index (ABI), as many patients with PAD are asymptomatic. Refer patients with significant claudication or a positive ABI for further vascular assessment and consider exercise, medications, and surgical options. Amputation and foot ulceration are the most common consequences of diabetic neuropathy and major causes of morbidity and disability in people with diabetes. Early recognition and management of independent risk factors can prevent or delay adverse outcomes. The risk of ulcers or amputations is increased in people who have had diabetes >10 years, are male, have poor glucose control, or have cardiovascular, retinal, or renal complications. The following foot-related risk conditions are associated with an increased risk of amputation:
- Peripheral neuropathy with loss of protective sensation.
- Altered biomechanics (in the presence of neuropathy)
- Evidence of increased pressure (erythema, hemorrhage under a callus).
- Bony deformity.
- Peripheral vascular disease (decreased or absent pedal pulses).
- A history of ulcers or amputation.
- Severe nail pathology.
A patient care handout on patient foot care is available from the Academy of Family Physicians at the following web site:
http://familydoctor.org/352.xml
Immunizations in Diabetic Patients
Influenza and pneumonia are preventable infectious diseases associated with a high morbidity and morality in the elderly and people with chronic diseases. All patients with diabetes should be offered an influenza vaccine if greater than 6 months of age. One lifetime vaccination of pneumococcal vaccination should be offered to all diabetic patients and revaccination for people > 64 years of age previously immunized when they were <65 years of age if the vaccine was administered > 5 years ago.
Diabetes Numbers At A Glance
Don’t feel overwhelmed! It is a lot of information but now you are armed with the latest information about the prevention, diagnosis, and management of type 2 diabetes. A great resource for you to download for summary is: