Is LDL cholesterol associated with long-term mortality among primary prevention adults? A retrospective cohort study from a large healthcare system.

OBJECTIVES: Among primary prevention-type adults not on lipid-lowering therapy, conflicting results exist on the relationship between low-density lipoprotein cholesterol (LDL-C) and long-term mortality. We evaluated this relationship in a real-world evidence population of adults. DESIGN: Retrospective cohort study. SETTING: Electronic medical record data for adults, from 4 January 2000 through 31 December 2022, were extracted from the University of Pittsburgh Medical Center healthcare system. PARTICIPANTS: Adults without diabetes aged 50-89 years not on statin therapy at baseline or within 1 year and classified as primary prevention-type patients. To mitigate potential reverse causation, patients who died within 1 year or had baseline total cholesterol (T-C) ≤120 mg/dL or LDL-C <30 mg/dL were excluded. MAIN EXPOSURE MEASURE: Baseline LDL-C categories of 30-79, 80-99, 100-129, 130-159, 160-189 or ≥190 mg/dL. MAIN OUTCOME MEASURE: All-cause mortality with follow-up starting 365 days after baseline cholesterol measurement. RESULTS: 177 860 patients with a mean (SD) age of 61.1 (8.8) years and mean (SD) LDL-C of 119 (31) mg/dL were evaluated over a mean of 6.1 years of follow-up. A U-shaped relationship was observed between the six LDL-C categories and mortality with crude 10-year mortality rates of 19.8%, 14.7%, 11.7%, 10.7%, 10.1% and 14.0%, respectively. Adjusted mortality HRs as compared with the referent group of LDL-C 80-99 mg/dL were: 30-79 mg/dL (HR 1.23, 95% CI 1.17 to 1.30), 100-129 mg/dL (0.87, 0.83-0.91), 130-159 mg/dL (0.88, 0.84-0.93), 160-189 mg/dL (0.91, 0.84-0.98) and ≥190 mg/dL (1.19, 1.06-1.34), respectively. Unlike LDL-C, both T-C/HDL cholesterol (high-density lipoprotein cholesterol) and triglycerides/HDL cholesterol ratios were independently associated with long-term mortality. CONCLUSIONS: Among primary prevention-type patients aged 50-89 years without diabetes and not on statin therapy, the lowest risk for long-term mortality appears to exist in the wide LDL-C range of 100-189 mg/dL, which is much higher than current recommendations. For counselling these patients, minimal consideration should be given to LDL-C concentration.

REMAP Periop: a randomised, embedded, multifactorial adaptive platform trial protocol for perioperative medicine to determine the optimal enhanced recovery pathway components in complex abdominal surgery patients within a US healthcare system.

INTRODUCTION: Implementation of enhanced recovery pathways (ERPs) has resulted in improved patient-centred outcomes and decreased costs. However, there is a lack of high-level evidence for many ERP elements. We have designed a randomised, embedded, multifactorial, adaptive platform perioperative medicine (REMAP Periop) trial to evaluate the effectiveness of several perioperative therapies for patients undergoing complex abdominal surgery as part of an ERP. This trial will begin with two domains: postoperative nausea/vomiting (PONV) prophylaxis and regional/neuraxial analgesia. Patients enrolled in the trial will be randomised to arms within both domains, with the possibility of adding additional domains in the future. METHODS AND ANALYSIS: In the PONV domain, patients are randomised to optimal versus supraoptimal prophylactic regimens. In the regional/neuraxial domain, patients are randomised to one of five different single-injection techniques/combination of techniques. The primary study endpoint is hospital-free days at 30 days, with additional domain-specific secondary endpoints of PONV incidence and postoperative opioid consumption. The efficacy of an intervention arm within a given domain will be evaluated at regular interim analyses using Bayesian statistical analysis. At the beginning of the trial, participants will have an equal probability of being allocated to any given intervention within a domain (ie, simple 1:1 randomisation), with response adaptive randomisation guiding changes to allocation ratios after interim analyses when applicable based on prespecified statistical triggers. Triggers met at interim analysis may also result in intervention dropping. ETHICS AND DISSEMINATION: The core protocol and domain-specific appendices were approved by the University of Pittsburgh Institutional Review Board. A waiver of informed consent was obtained for this trial. Trial results will be announced to the public and healthcare providers once prespecified statistical triggers of interest are reached as described in the core protocol, and the most favourable interventions will then be implemented as a standardised institutional protocol. TRIAL REGISTRATION NUMBER: NCT04606264.