Chemoprevention

Aspirin for the Primary Prevention of Cardiovascular Events

Clinical Considerations

• Decisions about aspirin therapy should take into account overall risk for coronary heart disease. Risk assessment should include asking about the presence and severity of the following risk factors:
• age,
• sex,
• diabetes,
• elevated total cholesterol levels,
• low levels of high-density lipoprotein (HDL) cholesterol,
• elevated blood pressure,
• family history (in younger adults), and,
• smoking
• Men older than 40 years, postmenopausal women, and younger people with risk factors for CHD (e.g., hypertension, diabetes, or smoking) are at increased risk for heart disease and may wish to consider aspirin therapy.
• Discussions about aspirin therapy should focus on potential coronary heart disease benefits, such as prevention of myocardial infarction, and potential harms, such as gastrointestinal and intracranial bleeding. Discussions should take into account individual preferences and risk aversions concerning myocardial infarction, stroke, and gastrointestinal bleeding.
• Although the optimal timing and frequency of discussions related to aspirin therapy are unknown, reasonable options include every 5 years in middle aged and older people or when other cardiovascular risk factors are detected.
• Most participants in the primary prevention trials of aspirin therapy have been men between 40 and 75 years of age. Current estimates of benefits and harms may not be as reliable for women and older men.
• Although older patients may derive greater benefits because they are at higher risk for CHD and stroke, their risk for bleeding may be higher.
• Uncontrolled hypertension may attenuate the benefits of aspirin in reducing CHD.
• The optimum dose of aspirin for chemoprevention is not known. Primary and secondary prevention trials have demonstrated benefits with a variety of regimens, including 75 mg per day, 100 mg per day, and 325 mg every other day. Doses of approximately 75 mg per day appear as effective as higher doses; whether doses below 75 mg per day are effective has not been established. Enteric-coated or buffered preparations do not clearly reduce adverse gastrointestinal effects of aspirin. Uncontrolled hypertension and concomitant use of other nonsteroidal anti-inflammatory agents or anticoagulants increase risk for serious bleeding.

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Folic Acid

Who is at risk?

All women planning to become pregnant are at average risk. They should be screened opportunistically and advised Folic acid supplementation (A)

Intervention

Folate supplementation –

• Women with increased risk: 5 mg/day supplementation ideally beginning 3 months before conception and for first trimester
• Women with average risk: 0.5 mg/day supplementation ideally beginning 3 months before conception and for the first trimester

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Vitamin D

Most supplementation trials of the effects of vitamin D on bone health also include calcium, so it is not possible to isolate the effects of each nutrient. The authors of a recent evidence-based review of research concluded that supplements of both vitamin D3 (at 700-800 IU/day) and calcium (500-1,200 mg/day) decreased the risk of falls, fractures, and bone loss in elderly individuals aged 62-85 years.

Adequate vitamin D status, (serum 25(OH)D of 30 ng/mL or more) the level usually achieved with a daily oral intake of at least 400 to 600 IU Supplements and fortified foods are an alternative source for women not able to consume enough dietary calcium to reach the recommended daily intake. They are best taken with meals and in divided doses (500 mg or less at one time) to maximize absorption and with a large glass of water Encouraging adequate intake of calcium should be a goal of all healthcare management of peri- and postmenopausal women.

The diet of all infants, children, and adolescents should include the recommended adequate intakes of vitamin D (200 IU [5.0 micrograms] or 500 ml of vitamin D-fortified formula or milk per day [Institute of Medicine, Food and Nutritional Board, 1997; Gartner & Greer, 2003]) as well as fruits and vegetables that are sources of potassium and bicarbonate, which may improve calcium retention

The new Clinician’s Guide recommends that adults over age 50 get 1,200 mg of calcium and 800-1,000 IU of vitamin D3 daily. Vitamin D3 is the form of vitamin D that best supports bone health. It is also called cholecalciferol.

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Calcium

Calcium intake

(From National Guideline Clearing House), No clear level of evidence

Adequate calcium intake (in the presence of adequate vitamin D status) has been shown to reduce bone loss in peri- and postmenopausal women and reduce fractures in postmenopausal women older than age 60 with low calcium intakes and it is considered a key component of any treatment regimen for patients with established osteoporosis

The target calcium intake for most postmenopausal women is 1,200 mg/day (approximately 3 cups daily of dairy products)

For calcium, the recommended intake is listed as an Adequate Intake (AI), which is a recommended average intake level based on observed or experimentally determined levels. Table 1 contains the current recommendations for calcium for infants, children and adults.

*mg=milligrams

Source

Milk, yogurt and cheese are the major contributors of calcium in the typical diet. The U.S. Department of Agriculture's Food Guide Pyramid recommends that individuals two years and older eat 2-3 servings of dairy products per day. A serving is equal to:

• 1 cup (8 fl oz) of milk
• 8 oz of yogurt
• 1.5 oz of natural cheese (such as Cheddar)
• 2.0 oz of processed cheese (such as American)

Adequate intake of dietary calcium should be encouraged for all family members calcium intake can be assessed periodically with a simple questionnaire. Suggested ages for screening are 2 to 3 years of age, after the transition from human milk or formula; 8 to 9 years of age during preadolescence; and again during adolescence, when the peak rate of bone mass accretion occurs

Targets for assessing calcium intake include general diet and lifestyle practices related to bone health Sources are: milk, dairy products, yogurt and cheese. Non dairy products include soy products and calcium supplements (3 age appropriate servings of dairy products per day.

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Created by: Dr Farouq Al-Zurba