Poor achievement of lipid targets after acute coronary syndrome: what can we improve?

Overcoming problems that impede the delivery of evidence‐based care is needed to bridge gaps between science and improving health

The benefits of lipid‐lowering therapy for the secondary prevention of atherosclerotic cardiovascular disease, including its effect on mortality, have been recognised since the publication of the seminal 4S trial in 1994.1 Recent clinical trials of novel lipid‐lowering therapies in people taking statins have found that the lower the low‐density lipoprotein cholesterol (LDL‐C) level achieved, the lower the risk of adverse cardiovascular events.2 It is beyond doubt that people at high risk of adverse cardiovascular events, including those with a history of acute coronary syndrome, benefit most from aggressive lipid‐lowering therapy. Accordingly, the recommended LDL‐C targets are lowest for such people, and have been continually reduced in international guidelines over time.3

Do people at high risk of cardiovascular events, including those who have experienced an acute coronary syndrome, achieve these lipid targets? In this issue of the MJA, Alsadat and colleagues4 report their analysis of data from the Cooperative National Registry of Acute Coronary Care, Guideline Adherence and Clinical Events (CONCORDANCE) for 2671 people who had survived an acute coronary syndrome during 2009–2018 and for whom lipid profile measurements six or twelve months after discharge were available. The authors found that 1194 of these people (45%) had not achieved target lipid levels (LDL‐C≤1.8mmol/L or total cholesterol ≤4mmol/L) at the most recent assessment. Women, people under 65years of age, and patients prescribed fewer than four evidence‐based medications or not prescribed intensive lipid‐lowering therapy on discharge were particularly unlikely to achieve lipid targets.4 If the 2019 European guidelines recommendation had been applied (LDL‐C<1.4mmol/L in patients at high risk of cardiovascular events),3 even fewer people in the study by Alsadat and colleagues would have achieved their target.

Why is there a gap between the guidelines and real world outcomes? Alsadat and colleagues4 noted that 9130 patients were followed up six months after an acute coronary syndrome, but lipid measurements were undertaken at six or twelve months in only 2671 (29%). This finding echoes international reports of suboptimal lipid monitoring, even in people at high risk.5 Inadequate lipid monitoring probably accentuates the challenges associated with therapeutic inertia in physicians and contributes to failures to appropriately modify lipid‐lowering therapy. The situation is made worse by patients not adhering to statin therapy because of media reports of statin‐related adverse events, with some experiencing “nocebo” effects.6

The study by Alsadat and colleagues4 also highlights the fact that the full armament of lipid‐lowering therapy is not being used; for example, only 3% of patients who did not reach target lipid levels were prescribed combination high dose statin/ezetimibe therapy. This could reflect a weakness in traditional approaches to optimising lipid‐lowering therapy in Australia, which recommend a stepwise up‐titration or “treat to target” approach. Further: more prescriptions being written does not mean that more tablets are taken. Innovative approaches to lipid management should be explored, including combination pills and simplified algorithms for initiating de novo combination treatment at the index presentation.

Alsadat and colleagues4 found that smoking and being prescribed three or fewer evidence‐based medications on discharge were risk factors for not achieving lipid targets. This implies that secondary prevention measures were poorer for people who did not reach lipid targets. One could speculate that subgroups with poorer access to health care and education find it more difficult to attain the targets. These subgroups need to be identified, and specific interventions developed to reduce the impact of socio‐economic, geographic, and other factors on cardiovascular health.

The study by Alsadat and colleagues4 adds to an expanding body of evidence that suggests that women are less likely than men to achieve recommended lipid targets.5,7 Some authors have attributed this phenomenon to poor adherence and intolerance by women of the side‐effects of lipid‐lowering therapy.8,9 However, women are also less likely to be prescribed statins, or are prescribed lower doses.10 Further, women have traditionally been under‐represented in randomised clinical trials of statin therapy. Distinguishing between the societal and biological reasons for women not achieving lipid targets and for gender‐related differences in lipid management each require further investigation.

To overcome the systemic, physician‐ and patient‐related barriers to the effective management of lipid levels (Box), a comprehensive approach is needed. This begins with establishing a healthy patient–physician relationship to improve adherence to treatment, with building health literacy and involving patients in shared decision making as further crucial steps. As global scientific and pharmaceutical organisations drive advances in lipid management, Alsadat and colleagues4 provide a timely reminder that trials and guidelines are not automatically translated into better health. Overcoming problems that impede the delivery of evidence‐based care is challenging but requisite for bridging gaps between science and achieving lipid targets, and thereby improving cardiovascular health.

Box – Barriers to the effective management of lipid levels

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