Lipoprotein(a) and residual vascular risk in statin-treated patients with first acute ischemic stroke: A prospective cohort study

Frequency & factors associated with elevated lipoprotein-a among Ghanaian stroke survivors

BACKGROUND

Indigenous Africans are genetically predisposed to elevated lipoprotein-a (Lp(a)), a veritable risk factor for ischemic stroke. Recent studies have demonstrated the promising efficacy of therapeutic interventions for addressing elevated Lp(a) among patients at high risk of atherosclerotic cardiovascular events. It is important to assess the burden of elevated Lp(a) among stroke survivors of African ancestry aimed at addressing potential unmet therapeutic gaps for optimal secondary prevention.

PURPOSE

To assess the frequency of elevated lipoprotein-a among Ghanaian stroke survivors and factors associated with it.

METHODS

A prospective study conducted at the Neurology clinic of the Komfo Anokye Teaching Hospital among ischemic stroke survivors aged ≥18 years. Serum lipoprotein-a concentrations were measured using ELISA kits. A multivariate regression analysis was fitted to identify factors independently associated with elevated lipoprotein-a concentration > 30 mg/dl.

RESULTS

Among 116 stroke survivors, 35 (30.2%) had elevated Lp(a). The adjusted odds ratio (95% CI) of factors associated with elevated Lp(a) were female sex 3.09 (1.05-9.12), p = 0.04, diabetes mellitus 3.52 (1.32-9.40), p = 0.01, urban dwelling 4.64 (1.61-13.39), p = 0.005 and total cholesterol 1.85 (1.28-2.67), p = 0.001. Whereas the LDL cholesterol significantly decreased from baseline to month 12 among a subset of participants, the Lp(a) levels significantly increased from a baseline value of 29.38 ± 15.32 mg/dl to 40.97 ± 29.72 mg/dl, p = 0.032.

CONCLUSION

Approximately 1 in 3 Ghanaian ischemic stroke survivors harbor an elevated Lp(a) associated with female sex, urban residence, diabetes mellitus and raised cholesterol. This burden highlights an unmet therapeutic gap in secondary risk reduction in this resource-limited setting.

Intermediate and long-term residual cardiovascular risk in patients with established cardiovascular disease treated with statins

Introduction

Statins remain the first-line treatment for secondary prevention of cardiovascular (CV) events, with lowering of low-density lipoprotein cholesterol (LDL-C) being their therapeutic target. Although LDL-C reduction significantly lowers CV risk, residual risk persists, even in patients with well-controlled LDL-C; thus, statin add-on agents that target pathways other than LDL-C, such as the omega-3 fatty acid eicosapentaenoic acid, may help to further reduce persistent CV risk in patients with established CV disease.

Methods

This narrative review examines the contemporary literature assessing intermediate- and long-term event rates in patients with established CV disease treated with statins.

Results

CV event rates among patients treated with statins who have established CV disease, including coronary artery disease, cerebrovascular disease, or peripheral arterial disease, accumulate over time, with a cumulative incidence of CV events reaching up to approximately 40% over 10 years. Recurrent stroke occurs in up to 19% of patients seven years after a first cerebrovascular event. Repeat revascularization and CV-related death occurs in up to 38% and 33% of patients with peripheral artery disease after three years, respectively.

Discussion

Additional treatment strategies, such as eicosapentaenoic acid, are needed to reduce persistent CV risk in patients with established CV disease treated with statins.

Lipoprotein(a) and functional outcome of acute ischemic stroke when discordant with low-density lipoprotein cholesterol

BACKGROUND

Several studies have indicated that residual cardiovascular risk might be associated with elevated lipoprotein(a) [Lp(a)] even in the setting of controlled low-density lipoprotein cholesterol (LDL-C). We aimed to prospectively examine the association between Lp(a) and unfavorable functional outcome among patients with acute ischemic stroke when Lp(a) and LDL-C were discordant.

METHODS

Based on samples from the Infectious Factors, Inflammatory Markers and Prognosis of Acute Ischemic Stroke study, 973 patients with baseline plasma Lp(a) levels were included. The primary outcome was the composite outcome of death or major disability (modified Rankin Scale score of 3-6) at 6 months. Logistic regression models were used to estimate the risk for the primary outcome. Discordance analyses were performed, using difference in percentile units (>10 units), to detect the relative risk when Lp(a) and LDL-C were discordant.

RESULTS

In total, 201 (20.7%) participants experienced major disability or death at 6 months. The multivariable-adjusted odds ratio (OR) for the highest quartile was 1.88 [95% confidence interval (CI): 1.16-3.04] compared with the lowest quartile. Each 1-SD higher log-Lp(a) was associated with a 23% increased risk (95% CI: 2%-47%) for the primary outcome. Compared with the concordant group, the high Lp(a)/low LDL-C discordant group was associated with increased risk for the primary outcome (adjusted OR: 1.59, 95% CI: 1.01-2.52).

CONCLUSIONS

Elevated plasma Lp(a) levels were associated with increased risk of major disability and death at 6 months. Discordantly high Lp(a)/low LDL-C was associated with an unfavorable functional outcome, supporting the predictive potential of plasma Lp(a) after ischemic stroke, especially when discordant with LDL-C. Key messages What is already known on this topic Previous studies have indicated that a positive association between increased lipoprotein(a) [Lp(a)] and cardiovascular disease risk remained even in patients who achieved controlled low-density lipoprotein cholesterol (LDL-C) levels. The findings of studies exploring the association between Lp(a) and unfavorable clinical outcomes of stroke were inconsistent, and whether Lp(a) can predict the risk of unfavorable functional outcome in stroke patients when Lp(a) and LDL-C levels are discordant remains unknown. What this study adds Elevated plasma Lp(a) levels were associated with increased risk of major disability and death at 6 months beyond LDL-C levels in acute ischemic stroke patients. How this study might affect research, practice, or policy The combination of LDL-C-lowering therapies and Lp(a)-lowering therapies may have better clinical efficacy for patients with ischemic stroke, and it is of great clinical interest to further explore this possibility in dedicated randomized trials.