January 23rd, 2014

Prevention Guidelines in Practice: Vignette 2

This vignette is the second in our series “Making Sense of the New Prevention Guidelines — The View from Clinical Practice

A 45-year-old man sees you for cardiac risk assessment. His father died at age 42 from a myocardial infarction. He exercises regularly and feels he eats well. He does not smoke. His blood pressure is 135/83 mm Hg. BMI is 26 kg/m². Fasting lipid panel shows an LDL of 150 mg/dL.

  • Should other markers of risk be obtained? CRP, Lp(a), CIMT, CAC score?
  • Do you recommend any specific treatment – should he take a statin?
  • Have the new ACC/AHA guidelines (risk assessment, blood cholesterol) influenced your approach to this patient?


5 Responses to “Prevention Guidelines in Practice: Vignette 2”

  1. First of all, I’d like to know his waist circumference since that tends to be a better predictor of CVD risk than BMI.
    For sure we need to look at the rest of the lipid panel. Please give us the TC, TG and HDL-C levels, from which I may need to calculate the non-HDL-C.
    Yes, additional markers would be useful, starting with a glucose from his fasting blood specimen, since he might have impaired fasting glucose or even diabetes. Also, an Lp(a) level and CAC are probably useful and cost-effective in directing treatment given his age and family history. Although his BMI is in the range where the CRP might well be elevated, virtually every lipid medication lowers CRP so I do not often find it useful. Carotid ultrasound for CIMT is reasonable but not as useful overall as CAC, and especially less so when the family history is positive for MI and not for stroke.

    Yes, a statin is almost certainly required given that his LDL-C probably should be under 100, or at least under 130. Depending on the other factors above, a low-intensity statin regimen might be enough, or mid-intensity may well be warranted. I would definitely follow his LDL-C (and perhaps non-HDL-C) response to make sure he was compliant and had achieved reasonable levels. Also, I would like to find out how much salt is in his “feels he eats well” diet, and depending on the course of his BP follow-up I would consider adding a BP med.

    No, sadly the new ACC/AHA guidelines would not influence my approach to this patient much at all. Although the lifetime risk calculator might help motivate the patient towards lifestyle and medical treatment, it seems likely that he is already well motivated. Meanwhile, with all due respect to the considerable erudition and effort of the ACC/AHA writing panelists, their deletion of LDL-C and non-HDL-C goals is to me a step backward. As hopefully non-lipidologists soon will learn, this step was not a result of new data showing that goals are no longer warranted, but rather due to exclusion of much evidence for the first time. In contrast, the full swath of evidence was in play for ATP-III, ESC and IAS guidelines and so differing evidence base is the reason why the 2013 ACC/AHA guidelines are the only ones without LDL goals.

  2. this gentle(man) is overweight, has a very significant family history and a high LDL levels.

    i would like to see HDL / non HDL levels too.

    the target LDL for this patient will be 130 and below.

    i would like to put him on LSM and dietary modifications, will reassess him 3 months later.

  3. Marios Savvides, MB, BS; FRACP says:

    In the patient presented the most important uncorrectable risk factor is the FAMILY HISTORY of very premature coronary disease AND SUDDEN DEATH. He is already attending to the other correctable risk factors. The new guidelines completely dismiss the family history which is by far and away the MOST IMPORTANT risk factor. The guidelines have intentionally excluded some of the evidence on ‘treating to targets'(TNT, PROVE IT TIMI-22 etc).
    The father died at 42 and the patient is already 45 so he may well have sub-clinical vascular disease. A CCTA and other imaging studies should be considered to determine any coronary plaque burden already present but it’s absence would still not sway away from treatment.
    Additional parameters such as TGs, non-HDL cholesterol, CRP, Lp(a), glucose etc would be important but if negative would still not influence the decision on therapy. In this instance I would go outside the guidelines (after all they are there to guide, not to follow to the letter) and commence him on low-intensity statin and in this case actually use the LDL-cholesterol and inflammatory markers as a guide. Guidelines are fine for the populations they are intended for, but when you have a patient in front of you, you have to adapt your approach to that individual; after all you may only get one chance to influence his outcome.
    Clinical experience and judgement sometimes have to override expert guidelines no matter how well-intentioned they are.

  4. I would be more aggressive than the new guidelines recommend. I feel like the LDL threshold of 190 as the only LDL based trigger for statins is quite restrictive and the family history always worries me. I would be up front with the patient and tell him that neither the old nor the new guidelines would recommend treatment, but that if his goal is a lifetime free of clinical atherosclerosis events, he should consider being more aggressive. I would recommend he consider either taking a statin or having a calcium scan to guide the decision and if he has the CAC scan, starting a statin for any CAC score > 0 (which would be notably high at his age). In my opinion, CAC scanning has value for individuals at low risk “with a twist” such as this patient, with high LDL and a family history. The scans cost between $50-100 in Dallas, so cost of the scan is not a major issue. Both of these alternatives are obviously more aggressive with the guidelines, but fit the epidemiology of the disease and what we know about the biology of LDL cholesterol.

  5. Neil Stone, MD says:

    The new guidelines listed four major groups for which there was evidence for benefit. But the guidelines don’t stop there. Figure 2 is not a summary of the entire guideline recommendations. The panel was mindful that there are situations where other factors should be considered. They are listed in several places in the guideline and they are to be used in the recommended clinician-patient discussion for primary prevention decisions.

    For those who wonder where this is noted, please look in the recommendations section page 24, or Figure 4 (page 31) or the text (page 33). The guidelines state that when a risk decision is uncertain, other factors that may influence ASCVD risk and may be used in the clinician-patient risk discussion. These include primary LDL-C level ≥160 mg/dL or other evidence of genetic hyperlipidemias; family history of premature ASCVD with onset before age 55 y in a first-degree male relative or before age 65 y in a first-degree female relative; high-sensitivity C-reactive protein level of ≥2 mg/L; coronary artery calcification score ≥300 Agatston units or ≥ 75th percentile for age, sex, and ethnicity (for additional information, see http://www.mesa-nhlbi.org/CACReference.aspx.); or ankle–brachial index <0.9 or lifetime ASCVD. (those who missed this are only looking at Figure 2 of the guidelines which was never meant to be an all inclusive summary of the guidelines) Table I in an online synopsis of the guideline appearing in Annals of Internal Medicine summarizes all the various points of the guidelines well (reference given below)

    In this case, a family history of premature ASCVD is a factor that the guidelines say may influence your decision. Thus, in young adults, even if a risk calculation is not possible or low, in those with factors such as a primary LDL-C ≥ 160 or a family history of premature ASCVD, the guidelines would support statin treatment. This should be done, however, in keeping with the risk discussion concept espoused by the guidelines by considering the entire risk factor profile, the potential for benefit as well as the potential for adverse effects and/or drug-drug interactions and including the patient preferences. This is why in the text we referred to the guidelines as patient-centered in primary prevention. The calculator doesn't determine statin treatment; the clinician and patient do.

    In this case, in my practice, I would discuss the following options: 1) Just intensive lifestyle with careful followup; 2) risk stratification with a coronary calcium score, or 3) treatment with a moderate intensity dose of a statin combined with optimal lifestyle.

    I tell the residents that sometimes eliciting a detailed family history and looking for calcium on CT scans they may have recently for other reasons can further inform these kinds of decisions. A family history of a sibling with ASCVD or a father with brothers/sisters with early ASCVD would make me more aggressive. Most often patients that I have seen are eager to know more precisely their risk and we discuss a oronary calcium score. Before I order, I see if a CT scan was ordered recently for another medical problem. I saw a patient like this recently who had extensive coronary calcification seen on an abdominal CT scan done for renal stones. He was unaware of this incidental finding. This strongly supported the decision to use a statin with optimal lifestyle.

    My plea for those who think the guidelines don't address patients like this is to review the synopsis in the Annals of Internal Medicine. Treatment of Blood Cholesterol to Reduce Atherosclerotic Cardiovascular Disease Risk in Adults: Synopsis of the 2013 ACC/AHA Cholesterol Guideline.
    Stone NJ, Robinson JG, Lichtenstein AH, Goff Jr DC, Lloyd-Jones DM, Smith Jr SC, Blum C, Schwartz JS; for the 2013 ACC/AHA Cholesterol Guideline Panel*.
    Ann Intern Med. 2014 Jan 28. doi: 10.7326/M14-0126. [Epub ahead of print] If you have time, read the new guideline start to finish. It's got a repository of information that can be useful to understanding what the panel did and why.