Association of Lipoprotein(a) Levels With Incidence of Major Adverse Limb Events

IMPORTANCE

High lipoprotein(a) (Lp[a]) levels are involved in the development of cardiovascular events, particularly in myocardial infarction, stroke, and peripheral artery disease. Studies assessing the Lp(a) levels associated with adverse lower-limb events are lacking.

OBJECTIVE

To assess the association between Lp(a) levels and incidence of major adverse limb events in unselected hospitalized patients.

DESIGN, SETTING, AND PARTICIPANTS

This large retrospective monocentric cohort study was conducted from January 1, 2000, to December 31, 2020. Data were derived from the clinical information system of the Hôpital Européen Georges-Pompidou, a Paris-based university hospital. Patients who underwent at least 1 Lp(a) measurement at the center during the study period were included. Patients who had no follow-up data or who had the first Lp(a) measurement after the study outcome had occurred were excluded. Data analyses were performed from May 2021 to January 2022.

MAIN OUTCOMES AND MEASURES

The primary outcome was the first inpatient major adverse limb event, defined as a major amputation, peripheral endovascular revascularization, or peripheral surgical revascularization, during follow-up. Secondary outcomes included individual components of the primary outcome. Lipoprotein(a) levels were categorized as follows: normal (<50 mg/dL), high (50 to <134 mg/dL), and very high (≥134 mg/dL); to convert Lp(a) values to milligrams per liter, multiply by 0.1.

RESULTS

A total of 16 513 patients (median [IQR] age, 58.2 [49.0-66.7] years; 9774 men [59.2%]) were included in the cohort. The median (IQR) Lp(a) level was 24 (10.0-60.0) mg/dL. The 1-year incidence of major adverse limb event was 2.44% in the overall population and 4.54% among patients with very high Lp(a) levels. High (adjusted accelerated failure time [AFT] exponential estimate: 0.43; 95% CI, 0.24-0.78; Benjamini-Hochberg-corrected P = .01) and very high (adjusted AFT exponential estimate: 0.17; 95% CI, 0.07-0.40; Benjamini-Hochberg-corrected P < .001) Lp(a) levels were independently associated with an increased risk of major adverse limb event.

CONCLUSIONS AND RELEVANCE

Results of this study showed that higher Lp(a) levels were independently associated with an increased risk of a major adverse limb event in hospitalized patients. The Lp(a) measurement needs to be taken into account to improve lower-limb vascular risk assessment.

Controversies about the systematic preoperative pharmacological treatment before pheochromocytoma or paraganglioma surgery

The question of systematic use of a pharmacological treatment before surgery in patients diagnosed with pheochromocytoma and paraganglioma (PPGL) remains highly controversial. While recent guidelines suggest that this should be used in all patients, some experienced teams consider it unnecessary in some cases, provided the surgery is performed in a dedicated center that has expert endocrinologists, cardiologists, surgeons, and anesthetists. This controversy is aimed at shedding light on the potential benefits and risks of such a treatment, focusing specifically on alpha blockers which are considered as the first-line medical treatments in patients with PPGL. After discussing the rationale for alpha blockers, hemodynamic instability, tolerance, and acute cardiac complications will then be discussed in the first part of the manuscript, defending a systematic use. The second section will focus on blood pressure control, tolerance of alpha blockers, and also the management of normotensive PPGL, examining the daily risks of PPGL and arguing against the systematic use of a preoperative pharmacological treatment before surgery. Finally, we will discuss the concept of expert centers and define the patients in whom the risk/benefit profile would favor the use of this preoperative treatment.