Effects of statin and antiplatelet therapy noncompliance and intolerance on patient outcomes following vascular surgery

Barriers to Antiplatelet and Statin Adherence Following Major Vascular Intervention

BACKGROUND

Antiplatelets and statins therapies are associated with improved cardiovascular outcomes following major vascular intervention. Many vascular surgery institutions are reporting improved prescribing rates for aspirin (ASA), P2Y12 antagonists, and statins. Nevertheless, there remains limited publication describing rates and patient-perceived barriers for postoperative adherence. The purpose of this study is to investigate patient nonadherence to antiplatelet and statin therapies following major vascular intervention.

METHODS

A retrospective review of patients who underwent major vascular intervention at a single academic center was performed. The prescribing rates of ASA, P2Y12 antagonists, and statins were reviewed. Postoperative adherence, defined as consistent intake as prescribed, was evaluated at 1, 3, 6, 9, and 12 months using electronic documentation of both follow-up clinic appointments and phone call assessments, then corroborated with pharmacy fulfilment records. Patient-reported barriers to medication adherence were also examined.

RESULTS

A total of 101 subjects underwent major vascular intervention between January 2020 and July 2020, 98% of whom were discharged on at least 1 antiplatelet or statin agent. Approximately 90% of patients were discharged with ASA, 32% with a P2Y12 antagonist, and 96% with a statin. All patients who maintained adherence up to 6 months continued to report adherence at 9 and 12 months. Consistent adherence at 12 months was documented in 76% of patients on ASA, 81% on P2Y12 antagonism therapy, and 73% on statins. New adverse drug reactions represented the most common barrier to achieving adherence (37% [n = 20]). Preoperative therapy with ASA, P2Y12 antagonists, and statins were all independently predictive of postoperative adherence to the same regimen (P ≤ 0.001). The female gender was also associated with higher rates of adherence to postoperative P2Y12 antagonism therapy (P ≤ 0.05).

CONCLUSIONS

The current prescribing rates for antiplatelet and statin agents are promising, but postoperative nonadherence remains a multifaceted issue.

Variability in guideline-directed medical therapy across sites and operators and long-term mortality and amputation outcomes risk in patients undergoing peripheral vascular interventions

BACKGROUND

The use of guideline-directed medical therapy (GDMT) in patients undergoing peripheral vascular interventions (PVIs) decreases the risk of death and amputation and may decrease hospital readmissions. The variability of GDMT prescription across sites and operators and the proportionality of risk is not well understood. We aimed to study the association between variability of GDMT prescription at the site and operator level and outcomes (including 90-day readmissions and 24-month all-cause mortality and major amputation).

METHODS

We examined GDMT discharge rates in PVIs performed between 2017 and 2018 using Medicare-linked Vascular Quality Initiative registry. GDMT included a statin, antiplatelet therapy, and angiotensin-converting enzyme inhibitor/angiotensin receptor blocker (ACE-i/ARB) if hypertensive. Quartiles (Q1-4) of GDMT rates were documented by operators and sites and variability was quantified using median odds ratios (MOR) and intraclass correlation (ICC). The association between lower GDMT rates (per 10%) by sites and operators with 90-day readmission were calculated using logistic regression, and with 24-month mortality and major amputation using parametric survival model. Models were adjusted for patient-level factors and included sites and operators nested within sites as 2 random effects.

RESULTS

GDMT rates for 17,147 patients across 223 sites and 1,263 operators ranged from 0% to 38% (Q1, MOR 1.43, 95%CI 1.39-1.47, P ≤ .001) to 57%-100% (Q4, MOR 1.48, 95%CI 1.44-1.51, P ≤ .001). Four percent of variance in GDMT use was explained by sites (ICC 3.9, 95%CI 2.9-5.3) and operators (ICC 4.1, 95%CI 3.1-5.4). A dose-response relationship was noted between lower GDMT rates and increased risk of 90-day readmission risk by sites (P = .021) and operators (P < .001). Lower GDMT prescription by site was associated with higher risk of 24-month mortality (HR = 1.07, 95%CI 1.02-1.13) and major amputation (HR = 1.08, 95%CI 1.01-1.15). Similar associations were found for GDMT use by provider (mortality HR = 1.05, 95%CI 1.02-1.08 and amputation HR = 1.04, 95%CI 1.00-1.08).

CONCLUSION

Both at the operator and health system level, there was significant variability in GDMT prescription following PVI, proportionally translating into risk for readmission, mortality, and major amputation. Targeted quality efforts should prioritize both operator and site levels to improve GDMT use and outcomes for patients undergoing PVI.

The Impact of Perioperative Morbidities, Lack of Discharge Aspirin, and Lack of Discharge Statin on Long Term Survival Following EVAR

OBJECTIVE

Adverse perioperative events and discharge medications both have the potential to impact survival following endovascular abdominal aortic aneurysm repair (EVAR). We hypothesize that variables such as blood loss, reoperation in the same hospital admission, and lack of discharge statin/aspirin have significant effect on long term survival following EVAR. Similarly, other perioperative morbidities, are hypothesized to affect long term mortality. Quantifying the mortality effect of perioperative events and treatment emphasizes to physicians the critical nature of preoperative optimization, case planning, operative execution and postoperative patient management.

METHODS

All EVAR in the Vascular Quality Initiative between 2003 and 2021 were queried. Exclusions were: ruptured/symptomatic aneurysm; concomitant renal artery or supra-renal intervention at the time of EVAR; conversion to open aneurysm repair at the time of initial operation; and undocumented mortality status at the 5 year mark postoperatively. 18,710 patients met inclusion criteria. Multivariable Cox regression time dependent analysis was performed to investigate the strength of mortality association of the exposure variables. Standard demographic variables and pre-existing major co-morbidities were included in the regression analysis to account for disproportionate, deleterious co-variables amongst those experiencing the various morbidities. Kaplan-Meier survival analysis was performed to provide survival curves for the key variables.

RESULTS

Mean follow up was 5.99 years and 5-year survival for included patients was 69.2%. Cox regression revealed increased long term mortality to be associated with the following perioperative events: reoperation during the index hospital admission (HR 1.21, P = .034), perioperative leg ischemia (HR 1.34, P = .014), perioperative acute renal insufficiency (HR 1.24, P = .013), perioperative myocardial infarction (HR 1.87, P < .001), perioperative intestinal ischemia (HR 2.13, P < .001), perioperative respiratory failure (HR 2.15, P < .001), lack of discharge aspirin (HR 1.26, P < .001), and lack of discharge statin (HR 1.26, P < .001). The following pre-existing co-morbidities correlated with increased long term mortality (P < .001 for all) : body mass index under 20 kg/m2, hypertension, diabetes, coronary artery disease, reported history congestive heart failure, chronic obstructive pulmonary disease, peripheral artery disease, advancing age, baseline renal insufficiency and left ventricular ejection fraction less than 50%. Females were more likely to have EBL >300 mL, reoperation, perioperative MI, limb ischemia and acute renal insufficiency than males (P < .01 for all). Female sex trended but was not associated with increased long term mortality risk (HR 1.06, 95% CI .995-1.14, P = .072).

CONCLUSIONS

Survival after EVAR is improved with optimal operative planning to facilitate evading the need for reoperation and ensuring patients without contra-indication are discharged with aspirin and statin medications. Females and patients with pre-existing co-morbidity are at particularly higher risk for perioperative limb ischemia, renal insufficiency, intestinal ischemia and myocardial ischemia necessitating appropriate preparation and preventative measures.

Prevalence of statin intolerance: a meta-analysis

AIMS

Statin intolerance (SI) represents a significant public health problem for which precise estimates of prevalence are needed. Statin intolerance remains an important clinical challenge, and it is associated with an increased risk of cardiovascular events. This meta-analysis estimates the overall prevalence of SI, the prevalence according to different diagnostic criteria and in different disease settings, and identifies possible risk factors/conditions that might increase the risk of SI.

METHODS AND RESULTS

We searched several databases up to 31 May 2021, for studies that reported the prevalence of SI. The primary endpoint was overall prevalence and prevalence according to a range of diagnostic criteria [National Lipid Association (NLA), International Lipid Expert Panel (ILEP), and European Atherosclerosis Society (EAS)] and in different disease settings. The secondary endpoint was to identify possible risk factors for SI. A random-effects model was applied to estimate the overall pooled prevalence. A total of 176 studies [112 randomized controlled trials (RCTs); 64 cohort studies] with 4 143 517 patients were ultimately included in the analysis. The overall prevalence of SI was 9.1% (95% confidence interval 8.0-10%). The prevalence was similar when defined using NLA, ILEP, and EAS criteria [7.0% (6.0-8.0%), 6.7% (5.0-8.0%), 5.9% (4.0-7.0%), respectively]. The prevalence of SI in RCTs was significantly lower compared with cohort studies [4.9% (4.0-6.0%) vs. 17% (14-19%)]. The prevalence of SI in studies including both primary and secondary prevention patients was much higher than when primary or secondary prevention patients were analysed separately [18% (14-21%), 8.2% (6.0-10%), 9.1% (6.0-11%), respectively]. Statin lipid solubility did not affect the prevalence of SI [4.0% (2.0-5.0%) vs. 5.0% (4.0-6.0%)]. Age [odds ratio (OR) 1.33, P = 0.04], female gender (OR 1.47, P = 0.007), Asian and Black race (P < 0.05 for both), obesity (OR 1.30, P = 0.02), diabetes mellitus (OR 1.26, P = 0.02), hypothyroidism (OR 1.37, P = 0.01), chronic liver, and renal failure (P < 0.05 for both) were significantly associated with SI in the meta-regression model. Antiarrhythmic agents, calcium channel blockers, alcohol use, and increased statin dose were also associated with a higher risk of SI.

CONCLUSION

Based on the present analysis of >4 million patients, the prevalence of SI is low when diagnosed according to international definitions. These results support the concept that the prevalence of complete SI might often be overestimated and highlight the need for the careful assessment of patients with potential symptoms related to SI.

Statins and Peripheral Arterial Disease: A Narrative Review

Peripheral arterial disease (PAD) is a highly prevalent atherosclerotic condition. In patients with PAD, the presence of intermittent claudication leads to a deterioration in quality of life. In addition, even in asymptomatic cases, patients with PAD are at high risk of cardiac or cerebrovascular events. Treatment of PAD is based on lifestyle modifications; regular exercise; smoking cessation; and control of cardiovascular risk factors, including hypercholesterolemia. A growing number of studies have shown that statins reduce cardiovascular risk and improve symptoms associated with PAD. Current guidelines recommend the use of statins in all patients with PAD in order to decrease cardiovascular events and mortality. However, the prescribing of statins in patients with PAD is lower than in those with coronary heart disease. This review provides relevant information from the literature that supports the use of statins in patients with PAD and shows their potential benefit in decreasing lower limb complications as well as cardiovascular morbidity and mortality.

Preoperative statin therapy is associated with higher 5-year survival after thoracic endovascular aortic repair

OBJECTIVE

Statin use is associated with higher long-term survival after abdominal aortic aneurysm repair. However, the association between statin use and survival after thoracic endovascular aortic repair (TEVAR) has not been established.

METHODS

We performed a review of prospectively collected data of all patients who had undergone TEVAR in the Vascular Quality Initiative between 2014 and 2020. We excluded patients aged <18 years, those who had presented with trauma, and those who had received custom-manufactured or physician-modified devices. We evaluated the association between preoperative statin therapy and in-hospital mortality and complications and 5-year mortality. We also analyzed the trend of preoperative statin use in elective cases for the previous 7 years. To account for nonrandom assignment to treatment, we used propensity score matching of patient characteristics, comorbidities, pathology, and urgency for preoperative statin use. We used logistic regression and Cox regression for the short-term and 5-year outcomes, respectively.

RESULTS

Of 6266 patients who had undergone TEVAR and met the inclusion criteria, 3331 (53%) patients had been taking a statin preoperatively, including 1148 of 2267 (64%) treated for aneurysmal disease. After propensity score matching, 1875 patients were in each cohort. Preoperative statin use was associated with lower rates of any perioperative complication (16.7% vs 19.6%; odds ratio, 0.82; 95% confidence interval [CI] 0.69-0.97; P = .022). Overall, preoperative statin use was also associated with lower 5-year mortality (18.8% vs 24.5%; hazard ratio [HR], 0.74; 95% CI, 0.63-0.89; P = .001). When stratified by urgency, preoperative statin use was associated with lower 5-year mortality after elective TEVAR (14.9% vs 22.4%; HR, 0.62; 95% CI, 0.49-0.79; P < .001) but not after urgent or emergent TEVAR (27.4% vs 29.1%; HR, 0.89; 95% CI, 0.70-1.14; P = .37). When stratified by pathology, preoperative statin use was associated with significantly lower 5-year mortality for patients with aneurysms (HR, 0.63; 95% CI, 0.48-0.83; P = .001). Although the mortality was also lower for patients with dissection and "other" pathology, these differences did not reach statistical significance. Between 2014 and 2019, a significant increase had occurred in statin use among patients undergoing elective TEVAR, from 56% in 2014 to 64% in 2019 (P = .007).

CONCLUSIONS

Preoperative statin therapy is associated with lower perioperative complication rates and 5-year mortality for patients undergoing TEVAR. All patients with known thoracic aortic pathology should receive statin therapy unless contraindications for the drug are present. For patients undergoing elective TEVAR, the statin prescription percentage should be considered a quality metric, and further implementation research should occur to improve preoperative statin use.