This decision aid was developed in conjunction with the PEER Simplified Lipid Guideline 2023 Update: Prevention and Management of Cardiovascular Disease in Primary Care. 

Simplified Guideline: https://www.cfp.ca/content/69/10/675
PEER Simplified Lipid Guideline 2023 Update: Prevention and Management of Cardiovascular Disease in Primary Care

Systematic Review: https://www.cfp.ca/content/69/10/701
Lipid-lowering therapies for cardiovascular disease prevention and management in primary care: A PEER Umbrella systematic review of systematic reviews

Contents

1. What does the PEER Simplified Cardiovascular Decision Aid do?

The PEER Simplified Cardiovascular Decision Aid is an interactive decision aid that gives individualized estimates of experiencing a cardiovascular event (such as a heart attack or stroke) over the next 10 years. It shows the impact lifestyle and medication options might have on your cardiovascular risk along with estimates of the side-effects and other considerations. You need to know all this information so you can make a decision that is best for you.

This aid is not intended for use in people who already have cardiovascular disease. In addition, while type 2 diabetes can be entered into the simplified decision aid as a risk factor it does not provide an estimate of the other important health outcomes related to diabetes such as vision changes and reduced kidney function. A diabetes specific decision aid is available at: https://decisionaid.ca/diabetes 
This diabetes decision aid was not developed as part of the lipid guideline process.

2. How to use this patient decision aid to estimate your cardiovascular risk

Estimating your risk

a) The impact of cardiovascular risk factors are known to differ across the world depending on geographical region so first choose the country where you live

b) Enter your relevant health information which is used to estimate your risk of cardiovascular events

c) Based on the information you have entered, your 10-year cardiovascular risk (or 5 years if you choose New Zealand) is shown using a 100-face icon array conveying an estimate of your cardiovascular risk (typically heart attacks and strokes)

d) The blue faces are those people like you who will not have a cardiovascular event where as the red faces are those who will have an event – the % risk is also shown above the icon array

Choose your treatments

You can select among lifestyle and medication options to see what impact they might have on your cardiovascular risk.

a) Lifestyle Options: You can select from two lifestyle options to see the estimated effects of these on cardiovascular risk. The change in cardiovascular risk will be shown on the icon array. Links to useful resources are provided.

b) Medication Options: You can also select from a number of medication options to see the estimated effects of these treatments on cardiovascular risk. Potential side-effects and other relevant considerations are displayed below the options.

c) Choosing both lifestyle and medication options: While multiple lifestyle options can be selected only one medication option is selectable at a time. When both lifestyle and medications are chosen, their cumulative effect is shown.

d) Documentation: The “EMR Note / Share Link” button creates a template note that can be copied and pasted into an EMR, and then edited as needed. It also provides a sharable link for future reference with all of the inputs currently selected in the decision aid. Finally, the “Print” button uses your web browser’s print function to print a copy of the decision aid on a single page in landscape orientation.

3. Why were the Framingham, SCORE-2, PREDICT, and ASCVD models chosen to estimate risk of cardiovascular outcomes in Step 1?

A variety of clinical prediction models (also known as "risk scores" or "risk calculators") have been developed to predict cardiovascular outcomes, each with their own strengths and limitations. We considered clinical prediction models based on the following factors:

1. Evaluated major cardiovascular events (e.g. cardiovascular death, myocardial infarction, stroke, with or without other outcomes like heart failure and peripheral artery disease);

2. Incorporated variables that are readily available in clinical practice;

3. Had been externally validated in at least 1 study in the region of interest; and

4. Demonstrated the best predictive power based on discrimination and calibration of available prediction models. The performance of each model is noted in the table below.

However, risk estimation is difficult. Many risk calculators tend to overestimate risk including recent calculators like the ASCVD Pooled Cohort Equation used in the United States (BMC Med. 2019 Jun 13;17(1):109.,Ann Intern Med. 2015 Feb 17;162(4):266-75). The Framingham Risk Score is also known to generally overestimate risk and a recent large Canadian study confirmed this (J Am Coll Cardiol. 2022 Oct 4;80(14):1330-1342). This study offered an adapted equation that partially corrected for the overestimation in Canada.  While we would have liked to use this updated data, it only predicts cardiovascular risk up to 5 years, and (like most other cardiovascular guidelines) the PEER guidelines used 10-year risk estimates to guide treatment recommendations. We did run a simulation by doubling the 5-year risk, recognizing this would slightly underestimate the 10-year. Using, a sample of 24 patients with a range of risk factors relevant to the models, we compared our 5-year double risk on the adapted model to the traditional Framingham model. Roughly, one would need to reduce the calculated risk in the Framingham model by 30-40% to get the risks seen in the Canadian adapted equation which is not dissimilar to what one would need to do for the ASCVD Pooled Cohort Equation.

Specific information about the different clinical prediction models can be found in the table below.

* c-statistic = the ability of prediction model to separate those who have an event from those who do not have an event. Measured by AUC/c-stat: the higher the c-stat, the better the predictive outcomes. A c-stat = 1 means the model perfectly predicts future outcome.

4. Where do the estimates of benefits and harms come from? 

The estimates of benefits and side-effects come from randomized controlled trials (RCTs) and meta-analyses of RCTs. Efficacy is reported as a relative risk. A patient’s individualized benefit is estimated by applying the cumulative relative risk reduction of all intervention selected. For side-effects, adverse events that were statistically significantly higher with therapy in RCTs are reported as absolute risk increases. The tables below provide detailed information about the specific numbers and evidence used. 

*The relative risk for blood pressure lowering is for use of a single blood pressure-lowering medication from one of 3 classes (thiazide, angiotensin-converting enzyme inhibitor [ACEI]/angiotensin-2 receptor blocker [ARB], or calcium-channel blocker [CCB]) at a typical dose. This does not account for baseline blood pressure or impact on blood pressure (change or achieved), or the use of multiple blood pressure-lowering medications.

Simplified Guideline: https://www.cfp.ca/content/69/10/675
PEER Simplified Lipid Guideline 2023 Update: Prevention and Management of Cardiovascular Disease in Primary Care

Systematic Review: https://www.cfp.ca/content/69/10/701
Lipid-lowering therapies for cardiovascular disease prevention and management in primary care: A PEER Umbrella systematic review of systematic reviews

Simplified Guideline: https://www.cfp.ca/content/69/10/675
PEER Simplified Lipid Guideline 2023 Update: Prevention and Management of Cardiovascular Disease in Primary Care

Systematic Review: https://www.cfp.ca/content/69/10/701
Lipid-lowering therapies for cardiovascular disease prevention and management in primary care: A PEER Umbrella systematic review of systematic reviews

5. How were costs estimated? (last updated 19 July 2023)

Cost estimates are based on Canadian dollars (CAD), updated annually or more frequently as needed, and estimated using the following websites:

• https://pricingdoc.acfp.ca/
• http://www.medi-mouse.com/drugfind.php
• https://www.studybuffalo.com/tools/drug-price-calculator/

6. When estimating risk why does saying the patient is taking a blood pressure medication increase their risk?

The effect on estimated risk seen from making changes to the variables reflects their ability to predict future cardiovascular events, and not necessarily their effect on cardiovascular events. In the case of blood pressure treatment, this is not the effect of putting people on these drugs, but that patients on hypertension medicines are at an increased risk compared to those not on treatment.

Calculator Developed by:
PEER Simplified Lipid Guideline Group

Programmed by:
Blair MacDonald BA, PharmD
PhD Student, Faculty of Pharmaceutical Sciences, University of British Columbia, Vancouver, BC

Translated by:
Nicolas Dugré PharmD, MSc, BCACP
Pharmacist at the CIUSSS du Nord-de-l’Île-de-Montréal and Clinical Associate Professor in the Faculty of Pharmacy at the University of Montreal in Quebec

Version history
Version 1.0 (last update: PUT IN DATE)

Last evidence review, July 2023

Update policy

Reviewed annually in January for consideration of update based on new evidence