November 17th, 2013
Clinical Lipidology Becomes a Controversial Field
Reva Balakrishnan, MD, MPH
Several Cardiology Fellows who are attending AHA.13 in Dallas this week are blogging for CardioExchange. The Fellows include Vimal Ramjee, Siqin Ye, Seth Martin, Reva Balakrishnan, and Saurav Chatterjee. You can find the previous post here. For more of our AHA.13 coverage of late-breaking clinical trials, interviews with the authors of the most important research, and blogs from our fellows on the most interesting presentations at the meeting, check out our AHA.13 Headquarters.
This morning, I was off to a slightly start and found myself scrambling for a seat at a well-attended session: Clinical Lipidology – Controversies in Cardiovascular Risk Reduction. I should have known that this would be overcrowded in light of the release of the prevention guidelines last week. The new guidelines have been a hot topic of daily conversation in our program amongst the trainees and experienced faculty. The speakers, many of whom helped develop the guidelines, seemed to be the subject of intense interrogation at times, with people lining up at the microphone demanding answers.
Topics were presented in a debate-like format with speakers on pro and con sides. They initially addressed evidence for statins in women and the elderly and race considerations. Karol Watson noted that diversity in most of the early statin trials was limited and that most of what we know about race effects is from subgroup analyses of larger trials that do show that statins confer benefit. When she pointed out lower LDL goal attainment rates and adherence in minority populations, one attendee was quick to note that the new guidelines could cause worse adherence rates in these patients if they are recommended to start on high-dose statins.
A lively debate ensued between Samia Mora and James Otvos over the utility of advanced lipid testing (apoB, LDL particle size). Dr. Otvos argued that in certain patients, LDL-C is not as accurate a marker of risk compared to LDL-P, pointing to an analysis of TNT that showed the patients who obtained the most benefit from high-dose statins were those with metabolic syndrome traits and discordantly high LDL-P. Dr. Mora presented robust evidence that no evidence to date has shown that advanced lipid testing improves CVD risk classification compared to total cholesterol/HDL ratio. Dr. Otvos “conceded,” stating that the benefit is not in the initial risk assessment but helps to identify the source of risk and tailor therapy in those with discordant numbers.
The last debate wasn’t much of a debate — on the treatment of HDL and TG (pro and con), which — to Neil Stone’s surprise (he was arguing the con side) — the pro speaker Alberico Catapano actually seemed to also be arguing the con side, focusing on the disappointing results of AIM HIGH and HPS2-THRIVE.
While half the crowd cleared at the 15-minute Q/A session at the end, those who remained lined up to ask questions about the new guidelines. Many people were concerned about the loss of the traditional treating to a number, and one attendee commented that while it is being promoted as a step forward, it feels like a step backwards.
At the end, the most insightful thought came from Dr. Stone, who compared guideline development to the story of Sisyphus, the Greek myth of the king who was forced to roll a boulder up the hill only to watch it roll down — once the guidelines get to the top, they will roll back down (that is, they will need to be redeveloped).
This session was lively, informative (and overcrowded) but left me with more questions than answers.
The formal information session for the new guidelines is planned for Wednesday – has anyone else attended a session where the guidelines have been discussed or debated? Was the session useful?
Love the Sisyphus metaphor. As Camus would have said, there is also a heroic quality in Sisyphus, to keep rolling up the boulder knowing that it will roll down again.
The other question in my mind related to the new guidelines is: since cholesterol goals are de-emphasized, how frequently (if at all?) should we be checking cholesterol levels once patients are initiated on appropriate moderate- or high- intensity statin therapy?
They actually commented on this – and it is in the new guidelines – that cholesterol levels should be checked after initiation of statins mainly to assess for compliance, and not for goal targeting!