Skip to main content
eScholarship
Open Access Publications from the University of California

Scholarly Works (25 results)

  • Article
  • Peer Reviewed
UCLA Previously Published Works (2015)
    Cover page: Should vascular effects of newer treatments be addressed more completely?
    • Article
    • Peer Reviewed
    UCLA Previously Published Works (2016)

    There has been considerable improvement in cancer survival rates, primarily through improved preventive strategies and novel anticancer drugs. Cancer is now becoming a chronic illness and as such both short and long-term cardiotoxic effects of cancer therapy are becoming more apparent. This has led to the emergence of a new multidisciplinary specialty known as cardio-oncology, with the purpose of identifying patients who are at a higher risk for developing cardiotoxicity so that appropriate surveillance, treatment and follow-up strategies may be instituted early. The mechanisms of cardiotoxicity caused by commonly used anticancer agents are reviewed, along with the latest advances in diagnostic and preventative strategies, with the overall objective of allowing cancer patients to continue both lifesaving and palliative treatments for their malignancy.

      Cover page: Concepts in cardio-oncology: definitions, mechanisms, diagnosis and treatment strategies of cancer therapy-induced cardiotoxicity.
      • Article
      • Peer Reviewed
      UCLA Previously Published Works (2023)

      Background

      Coronary artery calcium (CAC) has been widely recognized as an important predictor of cardiovascular disease (CVD). Given the finite resources, it is important to identify individuals who would receive the most benefit from detecting positive CAC by screening. However, the evidence is limited as to whether the burden of positive CAC on CVD differs by multidimensional individual characteristics. We sought to investigate the heterogeneity in the association between positive CAC and incident CVD.

      Methods

      This cohort study included adults from MESA (Multi-Ethnic Study of Atherosclerosis) ages ≥45 years and free of cardiovascular disease. After propensity score matching in a 1:1 ratio, we applied a machine learning causal forest model to (1) evaluate the heterogeneity in the association between positive CAC and incident CVD, and (2) predict the increase in CVD risk at 10-years when CAC>0 (versus CAC=0) at the individual level. We then compared the estimated increase in CVD risk when CAC>0 to the absolute 10-year atherosclerotic CVD (ASCVD) risk calculated by the 2013 American College of Cardiology/American Heart Association pooled cohort equations.

      Results

      Across 3328 adults in our propensity score-matched analysis, our causal forest model showed the heterogeneity in the association between CAC>0 and incident CVD. We found a dose-response relationship of the estimated increase in CVD risk when CAC>0 with higher 10-year ASCVD risk. Almost all individuals (2293 of 2428 [94.4%]) with borderline risk of ASCVD or higher showed ≥2.5% increase in CVD risk when CAC>0. Even among 900 adults with low ASCVD risk, 689 (69.2%) showed ≥2.5% increase in CVD risk when CAC>0; these individuals were more likely to be male, Hispanic, and have unfavorable CVD risk factors than others.

      Conclusions

      The expected increases in CVD risk when CAC>0 were heterogeneous across individuals. Moreover, nearly 70% of people with low ASCVD risk showed a large increase in CVD risk when CAC>0, highlighting the need for CAC screening among such low-risk individuals. Future studies are needed to assess whether targeting individuals for CAC measurements based on not only the absolute ASCVD risk but also the expected increase in CVD risk when CAC>0 improves cardiovascular outcomes.
        Cover page: Heterogeneity in the Association Between the Presence of Coronary Artery Calcium and Cardiovascular Events: A Machine-Learning Approach in the MESA Study
        • Article
        • Peer Reviewed
        UCLA Previously Published Works (2018)
        Coronary artery calcium (CAC) is a highly specific feature of coronary atherosclerosis. On the basis of single-center and multicenter clinical and population-based studies with short-term and long-term outcomes data (up to 15-year follow-up), CAC scoring has emerged as a widely available, consistent, and reproducible means of assessing risk for major cardiovascular outcomes, especially useful in asymptomatic people for planning primary prevention interventions such as statins and aspirin. CAC testing in asymptomatic populations is cost effective across a broad range of baseline risk. This review summarizes evidence concerning CAC, including its pathobiology, modalities for detection, predictive role, use in prediction scoring algorithms, CAC progression, evidence that CAC changes the clinical approach to the patient and patient behavior, novel applications of CAC, future directions in scoring CAC scans, and new CAC guidelines.
          Cover page: Coronary Calcium Score and Cardiovascular Risk
          • Article
          • Peer Reviewed
          UCLA Previously Published Works (2021)

          Background and aims

          HTN affects nearly 50% of U.S. adults and is the leading modifiable cardiovascular risk factor. A healthy diet and exercise can improve BP control, but adherence to these interventions is low. We tested whether a multimodal mind-body program, Mindful Awareness Practices (MAP) could improve BP and lifestyle behaviors associated with HTN when compared to a Health Promotion Program (HPP).

          Methods

          Adults with BP >120/80 were randomized to MAP or HPP. Outcome measurements of BP, self-reported diet, and exercise were analyzed with intent-to-treat group comparisons using repeated measures linear mixed models.

          Results

          There was an MAP-HPP between-group difference in interactions of time-by-systolic BP (P = 0.005) and time-by-diastolic BP (P = .003). The mean drops in SBP from baseline to week 13 for the MAP group was 19 mm Hg (138 ± 15 mm Hg-119 ± 6 mm Hg) compared to 7 mm Hg (134 ± 18 mm Hg-127 ± 22 mm Hg) in the HPP group. Similarly, a greater reduction in DBP was observed in the MAP group compared to the HPP group, 12 mm Hg (89 mm Hg ± 11-77 ± 7 mm Hg) and 1 mm Hg (81 ± 16 mm Hg-80 ± 18 mm Hg), respectively. Mediational analysis of the MAP group showed the total effect of mindfulness practice minutes on SBP with indirect effect (ab) of -.057 was significant, resulting in a 40% lower SBP for total effect (c) compared to direct (c') effect alone. The mediational model suggests MAP has a modest positive influence on participants initiating lifestyle behavior change, which partially explains the greater reduction in BP by the MAP group.

          Conclusion

          Our findings suggest a multimodal mind-body program involving mindfulness practice may improve BP control in adults with HTN.
            Cover page: Mindfulness effects on lifestyle behavior and blood pressure: A randomized controlled trial
            • Article
            • Peer Reviewed
            UCLA Previously Published Works (2023)
            Mitral regurgitation is the most common valvular disease, particularly in older adults. Recent literature has consistently supported that there are significant differences in mitral regurgitation outcomes between male and female patients and that this is likely multifactorial. Numerous sex differences in anatomy and pathophysiology may play a role in delayed diagnoses, referrals, and treatments for female patients. Despite the recognition of these discrepancies in the literature, many guidelines that steer clinical care do not incorporate these factors into society recommendations. Identifying and validating sex-specific diagnostic parameters and increasing the representation of female patients in trials of new mitral regurgitation treatment modalities are key factors in improving outcomes for female patients.
              Cover page: Mitral Regurgitation in Female Patients: Sex Differences and DisparitiesCreative Commons 'BY' version 4.0 license
              • Article
              • Peer Reviewed
              UCLA Previously Published Works (2015)

              Background

              Acculturation involves stress-related processes and health behavioral changes, which may have an effect on left ventricular (LV) mass, a risk factor for cardiovascular disease (CVD). We examined the relationship between acculturation and LV mass in a multiethnic cohort of White, African-American, Hispanic and Chinese subjects.

              Methods

              Cardiac magnetic resonance assessment was available for 5004 men and women, free of clinical CVD at baseline. Left ventricular mass index was evaluated as LV mass indexed by body surface area. Acculturation was characterized based on language spoken at home, place of birth and length of stay in the United States (U.S.), and a summary acculturation score ranging from 0 = least acculturated to 5 = most acculturated. Mean LV mass index adjusted for traditional CVD risk factors was compared across acculturation levels.

              Results

              Unadjusted mean LV mass index was 78.0 ± 16.3 g/m(2). In adjusted analyses, speaking exclusively English at home compared to non-English language was associated with higher LV mass index (81.3 ± 0.4 g/m(2) vs 79.9 ± 0.5 g/m(2), p = 0.02). Among foreign-born participants, having lived in the U.S. for ≥ 20 years compared to < 10 years was associated with greater LV mass index (81.6 ± 0.7 g/m(2) vs 79.5 ± 1.1 g/m(2), p = 0.02). Compared to those with the lowest acculturation score, those with the highest score had greater LV mass index (78.9 ± 1.1 g/m(2) vs 81.1 ± 0.4 g/m(2), p = 0.002). There was heterogeneity in which measure of acculturation was associated with LV mass index across ethnic groups.

              Conclusions

              Greater acculturation is associated with increased LV mass index in this multiethnic cohort. Acculturation may involve stress-related processes as well as behavioral changes with a negative effect on cardiovascular health.
                Cover page: Acculturation is associated with left ventricular mass in a multiethnic sample: the Multi-Ethnic Study of Atherosclerosis
                • Article
                • Peer Reviewed
                UCLA Previously Published Works (2021)

                Objectives

                Obstructive sleep apnoea (OSA) is a risk factor for hypertension (HTN), but the clinical progression of OSA to HTN is unclear. There are also sex differences in prevalence, screening and symptoms of OSA. Our objective was to estimate the time from OSA to HTN diagnoses in females and males.

                Design

                Retrospective analysis of electronic health records (EHR) over 10 years (2006-2015 inclusive).

                Setting

                University of California Los Angeles (UCLA) Health System in Los Angeles, California, USA.

                Participants

                4848 patients: females n=2086, mean (SD) age=52.8 (13.2) years; males n=2762, age=53.8 (13.5) years. These patients were selected from 1.6 million with diagnoses in the EHR who met these criteria: diagnoses of OSA and HTN; in long-term care defined by ambulatory visits at least 1 year prior and 1 year subsequent to the first OSA diagnosis; no diagnosis of OSA or HTN at intake; and a sleep study performed at UCLA.

                Primary and secondary outcome measures

                The primary outcome measure in each patient was time from the first diagnosis of OSA to the first diagnosis of HTN (OSA to HTN days). Since HTN and OSA are progressive disorders, a secondary measure was the relationship between OSA to HTN time and age (OSA to HTN=β1×Age+β0).

                Results

                The median (lower and upper quartiles) days from OSA to HTN were: all -532 (-1439, -3); females -610 (-1579, -42); and males -451 (-1358, 0). Older age in both sexes was associated with less time to a subsequent HTN diagnosis or more time from a prior HTN diagnosis (β1 days/year: all -16.9, females -18.3, males -15.9).

                Conclusions

                HTN was on average diagnosed years prior to OSA, with a longer separation in females. Our findings are consistent with underscreening of OSA, more so in females than males. Undiagnosed OSA may delay treatment for the sleep disorder and perhaps affect the development and progression of HTN.
                  Cover page: Which came first, obstructive sleep apnoea or hypertension? A retrospective study of electronic records over 10 years, with separation by sex
                  • Article
                  • Peer Reviewed
                  UCLA Previously Published Works (2015)
                  This study sought to investigate the relation between myocardial perfusion and N-terminal pro-brain natriuretic peptide (NT-proBNP) in asymptomatic adults without overt coronary artery disease. NT-proBNP is a cardiac neurohormone secreted from the ventricles in response to ventricular volume expansion and pressure overload and may also be elevated in the setting of reduced myocardial perfusion. We hypothesized that reduced myocardial perfusion reserve (MPR) would be associated with elevated NT-proBNP in participants free of overt cardiovascular disease. MPR was measured by cardiac magnetic resonance, before and after adenosine infusion, in 184 MESA participants (mean age 60 ± 10.4, 58% white, 42% Hispanic, 44% women) without overt cardiovascular disease. MPR was modeled as hyperemic myocardial blood flow (MBF) adjusted for MBF at rest. A linear regression analysis, adjusted for demographics, established cardiovascular risk factors, left ventricular mass, coronary calcium score, body mass index, and medications, was used to determine the association between MPR and NT-proBNP. Participants with low hyperemic MBF were more likely to be older, male, diabetic, and have higher blood pressure and higher coronary artery calcium score. Mean hyperemic MBF was 3.04 ± 0.829 ml/min/g. MPR was inversely associated with NT-proBNP levels. In a fully adjusted model, every 1-SD decrement in MPR was associated with a 21% increment in NT-proBNP (p = 0.04). In conclusion, MPR is inversely associated with NT-proBNP level in this cross-sectional study of asymptomatic adults free of overt coronary artery disease, suggesting that higher NT-proBNP levels may reflect subclinical myocardial microvascular dysfunction.
                    Cover page: Usefulness of N-terminal Pro–brain Natriuretic Peptide and Myocardial Perfusion in Asymptomatic Adults (from&nbsp;the Multi-Ethnic Study of Atherosclerosis)
                    • Article
                    • Peer Reviewed
                    UCLA Previously Published Works (2016)

                    With ongoing advancements in cancer-related treatments, the number of cancer survivors continues to grow globally, with numbers in the United States predicted to reach 18 million by 2020. As a result, it is expected that a greater number of patients will present with chemotherapy-related side effects. One entity in particular, chemotherapy-related cardiomyopathy (CCMP), is a known cardiotoxic manifestation associated with agents such as anthracyclines, trastuzumab, and tyrosine kinase inhibitors. Although such effects have been described in the medical literature for decades, concrete strategies for screening, prevention, and management of CCMP continue to be elusive owing to limited studies. Late recognition of CCMP is associated with a poorer prognosis, including a lack of clinical response to pharmacologic therapy, and end-stage heart failure. A number of advanced cardiac therapies, including cardiac resynchronization therapy, ventricular assist devices, and orthotopic cardiac transplantation, are available to for end-stage heart failure; however, the role of these therapies in CCMP is unclear. In this review, management of end-stage CCMP with the use of advanced therapies and their respective effectiveness are discussed, as well as clinical characteristics of patients undergoing these treatments. The relative paucity of data in this field highlights the importance and need for larger-scale longitudinal studies and long-term registries tracking the outcomes of cancer survivors who have received cardiotoxic cancer therapy to determine the overall incidence of end-stage CCMP, as well as prognostic factors that will ultimately guide such patients toward receiving appropriate end-stage care.

                      Cover page: Heart Failure Therapies for End-Stage Chemotherapy-Induced Cardiomyopathy.
                      Top