LDL Cholesterol Control Post-PCI Is Low and Linked to Worse Outcomes

Following PCI, only about half of patients have their LDL cholesterol measured and, of those who do, fewer than 60% have levels below 70 mg/dL, according to new registry data from Ontario, Canada.

This reflects “a gap in knowledge in terms of lipid management and statin management,” according to researchers.

“A lot of our patients after angioplasty, they kind of feel that ‘the doc fixed my lesion, I'm good, I'm going to take an aspirin and my dual antiplatelet therapy,’ and they kind of ignore everything else,” senior author Dennis Ko, MD (Institute for Clinical Evaluative Sciences and Peter Munk Cardiac Centre, Toronto, Canada), told TCTMD.

Craig Beavers, PharmD (University of Kentucky, Lexington), who wasn’t involved in the study, said when he counsels patients after PCI, he always stresses that the procedure has not cured their disease but rather acts as a temporary “Band-Aid,” and that they need to do more long-term work.

“When you have changes in your life that you're put in a situation where you're not sure what to do next, having those conversations really empowers that,” he told TCTMD, adding that healthcare providers across the board “need to continue to make sure that people are on their therapies, that they're assessing them, [and] that they're not overextrapolating the risk of statin therapy.”

LDL and Events

For the study, published in the September 22, 2020, issue of the Journal of the American College of Cardiology, Maneesh Sud, MD (Sunnybrook Health Sciences Centre, University of Toronto, Canada), Ko, and colleagues included all 47,884 patients without severe comorbidities and who did not reside in a nursing home who underwent an index PCI in the province of Ontario between October 2011 and September 2014. LDL cholesterol was measured in 52% of the population within 6 months of their procedure, and 57% had a measurement of below < 70 mg/dL, a traditional target for high-risk patients with atherosclerotic cardiovascular disease (ASCVD).

Median patient age was 63 years, 27% were women, and 62% presented with ACS. Median time to LDL measurement was 45 days. Among patients with LDL-cholesterol levels of < 70 mg/dL (n = 14,293), 70 to < 100 mg/dL (n = 6,880), and ≥ 100 mg/dL (n = 3,758), statins were taken by 87%, 75%, and 34%, respectively. The corresponding rates of high-intensity statin use were 59%, 41%, and 13% (P < 0.01 for trend).

Unsurprisingly, the rates of cardiovascular events—cardiovascular death, MI, coronary revascularization, and stroke—were directly correlated with LDL-cholesterol levels after a median follow-up of 3.2 years. This finding was maintained after multivariate adjustment.

CV Events by Post-PCI LDL-Cholesterol Level

Results were similar for the individual endpoints of MI and coronary revascularization, and cardiovascular death was only more likely for patients with LDL-cholesterol levels of 100 mg/dL and above (adjusted HR 1.33; 95% CI 1.05-1.68).

In subgroup analyses, the relationship between LDL cholesterol and MACE was even stronger for patients presenting with ACS compared with stable CAD (P for interaction < 0.01), but not for age above versus below 65 years (P = 0.06) or in connection to statin use among patients age 65 or older (P = 0.89).

Adherence and Efficacy

Despite Canada’s universal healthcare, Ko said he was surprised to see how few patients both had their LDL cholesterol measured in the first place and then controlled by 6 months. “Obviously cholesterol management has been a bit controversial,” he said, adding that guidelines have varied by country over time as to how often and in whom cholesterol should be checked. “So that is definitely something that could be improved upon.”

In an accompanying editorial, Robert S. Rosenson, MD (Icahn School of Medicine at Mount Sinai, New York), and colleagues write: “Considering the high prevalence of cardiovascular disease and widespread availability of generic medications for LDL cholesterol-lowering, the low frequency of LDL-cholesterol measurement and suboptimal achieved LDL-cholesterol levels represents an ongoing healthcare challenge.

“There is an urgent need to implement strategies that mandate systems approaches to more-frequent monitoring of LDL cholesterol,” they continue, “and a patient-physician/healthcare provider dialog that fosters health through lifestyle (diet, weight control) modifications, adherence to high-intensity statins and other class I preventive therapies, and use of nonstatin medications to lower LDL cholesterol in patients with suboptimal LDL cholesterol-lowering on maximum-tolerated statins.”

Ko advised assessing patient cholesterol levels within 6 months of PCI to check for adherence as well as efficacy. “Once you get them to a stable level and they're complying and such, you might not need to check it,” he said. “But personally, I do feel that having some numbers to know what it looks like and whether you need to do additional treatment is helpful.”

Beavers agreed, citing the 2018 American College of Cardiology and American Heart Association cholesterol guideline class 1A recommendation of checking LDL cholesterol every 3-12 months in secondary prevention patients with ASCVD on statins. “Does every patient need it every 3 months? Probably not. Maybe people you're concerned about or have some questionable issues, but for sure you could say every 12 months to assess adherence depending on the strategy,” he said. “But absolutely 4-12 weeks after a PCI, if you've started someone on statins or changed their dose, you should probably check on them and the guidelines support that.”

If statins aren’t working, “we have in this day and age a broad [range] of other agents we can use to help manage their LDL cholesterol,” Beavers continued, including ezetimibe, PCSK9 inhibitors, bempedoic acid, and likely soon inclisiran.

Going forward Ko said he would like to see future research address patient perspectives about statins. “It is important for us to understand if the prescription rate is about 60%, is that because the docs are not checking and didn't prescribe? Or is it the patient got prescribed and they stopped?” he said. “The underprescription of statin therapy has been a chronic story, but we haven't really made a ton of headway in this.”

Beavers said he would also like to see this study repeated within the United States and in a more-contemporary cohort, as well as “continual research into the complexities and the factors that play into medication adherence, and not just with statin therapy but with medication adherence as a whole, because we're still working and finding lots of ways to do that.”

Lastly, Beavers said, further studies should evaluate the potential for team-based care “to help advocate, manage, and educate these patients.”