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Key reviewer: Dr Michael Crooke, Chemical Pathologist, Wellington Hospital and Aotea Pathology

The New Zealand Guidelines Group has recently released their updated Cardiovascular Guidelines Handbook.

Topics covered in the handbook include:

  • Cardiovascular risk assessment and diabetes screening
  • Cardiovascular risk factor management
  • Smoking cessation
  • Atrial fibrillation
  • Coronary heart disease
  • Stroke and transient ischaemic attack
  • Rheumatic fever (new)
  • Prevention of infective endocarditis (new)
  • Heart failure

The following article details the changes to the handbook that may affect day-to-day practice.

Cardiovascular Risk charts

There are two main differences in the cardiovascular risk charts:

  • Ages bands on the risk charts now state an age range (i.e. 55�64 years), instead of choosing the age closest to the patient (i.e. 60 years)
  • Only systolic blood pressure is required for the calculation of risk
In practice: Less ambiguity for both age and blood pressure making the charts easier to use

Non-fasting blood tests may be used in some circumstances

Initial assessment using fasting blood tests remains recommended practice. When a fasting blood sample is not possible non fasting bloods may be used as follows:

  • Cholesterol HDL ratio: fasting status has little effect on total and HDL cholesterol (Although fasting bloods are still required for management, as triglycerides are used to calculate LDL cholesterol)
  • HbA1c: HbA1c can be used for initial screening for diabetes. Result ? 6% indicates the need for fasting plasma glucose
In practice: Rather than lose an opportunity for CVD risk assessment, non fasting bloods may be used.

Renal disease recognised as contributing to cardiovascular risk

eGFR has become well accepted as a means of assessing renal function, therefore the handbook recommends that both ACR (albumin : creatinine ratio) and eGFR have roles in assessing renal function, and in guiding further management of those with diabetes or renal disease.

People with an eGFR <60ml/min/1.73m2 should begin having CVD risk assessments at age 35 years for men and age 45 years for women.

In practice: Start CVD risk assessment for people with an eGFR <60ml/min/1.73m2 at age 35 years for men and age 45 years for women

Lipids targets lower

Optimal targets for lipids for people with CVD, diabetes or a calculated CVD risk greater than 15% are lower than in the previous handbook.

The target for:

  • LDL cholesterol is now less than 2.0 mmol/L (down from 2.5 mmol/L)
  • Total cholesterol/HDL ratio is now less than 4.0 (down from <4.5)
  • Total cholesterol remains at less than 4.0 mmol/L
In practice: Be aware of new optimal targets for lipid lowering, more aggressive treatment may be required

New blood pressure target people with chronic kidney disease

The handbook now recommends more aggressive management of blood pressure for people with chronic kidney disease, setting a target of less than 125/75 mmHg.

In practice: Be aware of new optimal targets for blood pressure in people with chronic kidney disease, more aggressive treatment may be required.

Change in the recommended frequency of CVD risk assessment

The new handbook recommends frequent CVD risk assessments for people with a CVD risk of between 10�15%. These people should have a CVD risk assessment every two years.

In practice: Update your recalls for people with a CVD risk of 10�15%

Metabolic syndrome no longer recognised as a separate risk factor

The definition of metabolic syndrome as an entity remains contentious, and there is no clear evidence of its importance as a risk factor, aside from the other recognised risk factors for CVD.

See BPJ 18 (December 2008) “Metabolic Syndrome: Useful or not?”

Universal BMI target

Separate BMI’s for Māori and Pacific peoples have been omitted; the handbook now includes one BMI table. A BMI of less than 25kg/m2 is considered desirable. This level may be lower for people of Asian descent.

Advice on diabetes management has been removed.

Advice on diabetes management has been removed pending a full revision of the Type 2 Diabetes Management Guideline due in 2010.

New Zealand Cardiovascular Guidelines Handbook 2009 Edition. Available from: www.nzgg.org.nz (downloadable online version plus order form for hard copy).