On secondary prevention after acute coronary syndrome : -what, when, and who

Abstract: BackgroundCardiovascular disease, of which coronary heart disease constitutes the lion’s share, is the leading cause of premature morbidity and mortality worldwide. Management of the condition has evolved rapidly in recent decades, and mortality has more than halved in the western world. Because of intense research, solid evidence supports effective and inexpensive means of preventing disease progression. However, secondary prevention still yields disappointingly low success in meeting guideline-recommended risk factor targets. It is therefore vital to develop more effective risk factor management.AimsWe aimed to assess the feasibility of a nurse-led, telephone-based, secondary preventive intervention in an unselected population with acute coronary syndrome (ACS). Furthermore, we sought to evaluate the flexibility of the intervention to adapt to a change in guidelines. We also aimed to evaluate whether the intervention was more effective than usual care at improving risk factor levels for blood pressure (BP) and low-density lipoprotein cholesterol (LDL-C) 12 months after discharge. Finally, we aimed to measure whether the intervention improved long-term adherence to statins.MethodsAll papers are based on the Nurse-based Age-independent Intervention to Limit Evolution of Disease after ACS (NAILED-ACS) trial. The NAILED trail has two arms, one after stroke/transient ischemic attack (NAILED-Stroke) and one after ACS (NAILED-ACS). All studies are based on NAILED-ACS aside from study II which includes both arms. The trial was an open, 1:1 randomized, controlled, parallel group trial that compared nurse-led telephone follow-up with medical titration (intervention) to a control group with follow-up by a general practitioner (control). All patients admitted to Östersund Hospital for ACS during 2010–2014 were eligible if available for preventive management by telephone. A baseline assessment was made at 1 month after discharge and thereafter every 12 months for at least 3 years. Feasibility was assessed among patients admitted until 31 January 2013, and predictors of exclusion and non-participation were identified. The performance of the intervention in implementing a guideline change was evaluated in patients with diabetes with both ACS and stroke as inclusion events after a change in LDLC target from <2.5 mmol/L to <1.8 mmol/L. LDL-C levels were compared between intervention and control patients before and after the guideline changed. Reasons for not reaching the target level were recorded. The outcomes of the intervention on BP and LDL-C were studied in patients admitted until 31 December 2013. We measured proportions reaching targets and levels of LDL-C and BP during the first 12 months of follow-up, with comparisons between the intervention and control groups. Adherence to statin treatment was measured in the entire study cohort, with at least 36 months of follow-up, with classification of reasons and analysis of predictors for both a first and a permanent discontinuation.ResultsOf 907 screened patients with ACS in the first study, 72.9% were included, and 11% declined participation. Among the 16.1% who were excluded, the predominant reasons were participation in other trial, dementia, and advanced disease. Non-included patients were significantly older, with more comorbidities, decreased functional capability, and lower level of education compared to included. Excluded and declining patients also had a reduced oneyear survival in comparison with included.Before the guideline changed, 96% of the 101 patients in the intervention group reached LDL-C <2.5 mmol/L compared to 70% of the 100 control patients (p<0.001). One year after target reduction to <1.8 mmol/L, the same proportions were 65% and 36%, respectively (p<0.001). The predominant reason for nonattainment of target in the intervention group was full-dose treatment; for the control group, it was that no medication adjustment was made. After medical titration, at 1 month (baseline), 94.1% in the intervention group achieved target for LDL-C (<2.5 mmol/L) compared to 68.4% in the control group. Mean LDL-C was 0.38 mmol/L lower in the intervention group (p<0.05 for both). At the 12-month assessment, 77.7% of the intervention group attained the LDL-C target compared to 63.2% of the control group, and mean LDL-C was 0.3 mmol/L lower among intervention patients (p<0.05 for both). In the intervention group, 91.9% achieved targets for systolic BP and 96.2% for diastolic BP after baseline titration compared to 65.6% and 82.0%, respectively, in the control group (p<0.05 for both). At 12 months, 68.9% in the intervention group reached the target for systolic BP and 88.1% for diastolic BP, compared to 63.7% and 82.8%, respectively, in the control group (p=0.125 and <0.05). Mean systolic BP was 7 mmHg lower and mean diastolic BP 4 mmHg lower in the intervention group after 1-month titration compared to controls. At 12 months, the mean systolic BP was 1.5 mmHg lower and mean diastolic BP 2.1 mmHg lower in the intervention group.In our assessment of adherence to statin treatment, 89.3% in the intervention group and 81.7% in the control group were adherent to treatment during a mean follow-up of 3.9 years (p<0.001). In the intervention group, 27.8% discontinued at least once during the period, compared to 20.8% in the control group (p<0.05). The main reason for a first discontinuation was avoidable in both groups: sideeffects without a compelling association with treatment. The main reason for permanent discontinuation was predominantly non-avoidable in the intervention group (advanced disease and dementia) but avoidable in the control group (sideeffects without a compelling association with treatment). Predictors for increased risk for discontinuation were female sex, and for a first event, inclusion in the intervention group. Predictors for reduced risk of non-adherence were ST elevation myocardial infarction as an including event, and for permanent discontinuation, inclusion in the intervention group.ConclusionA nurse-led telephone-based method for secondary prevention can encompass a large proportion of an ordinary ACS cohort. Compared to usual care, it is more adaptable to changes in treatment guidelines and leads to better achievement of major risk factor targets as well as improved medication adherence.