Favorable Antiviral Effect of Metformin on Severe Acute Respiratory Syndrome Coronavirus 2 Viral Load in a Randomized, Placebo-Controlled Clinical Trial of Coronavirus Disease 2019

BACKGROUND

Metformin has antiviral activity against RNA viruses including severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The mechanism appears to be suppression of protein translation via targeting the host mechanistic target of rapamycin pathway. In the COVID-OUT randomized trial for outpatient coronavirus disease 2019 (COVID-19), metformin reduced the odds of hospitalizations/death through 28 days by 58%, of emergency department visits/hospitalizations/death through 14 days by 42%, and of long COVID through 10 months by 42%.

METHODS

COVID-OUT was a 2 × 3 randomized, placebo-controlled, double-blind trial that assessed metformin, fluvoxamine, and ivermectin; 999 participants self-collected anterior nasal swabs on day 1 (n = 945), day 5 (n = 871), and day 10 (n = 775). Viral load was quantified using reverse-transcription quantitative polymerase chain reaction.

RESULTS

The mean SARS-CoV-2 viral load was reduced 3.6-fold with metformin relative to placebo (-0.56 log10 copies/mL; 95% confidence interval [CI], -1.05 to -.06; P = .027). Those who received metformin were less likely to have a detectable viral load than placebo at day 5 or day 10 (odds ratio [OR], 0.72; 95% CI, .55 to .94). Viral rebound, defined as a higher viral load at day 10 than day 5, was less frequent with metformin (3.28%) than placebo (5.95%; OR, 0.68; 95% CI, .36 to 1.29). The metformin effect was consistent across subgroups and increased over time. Neither ivermectin nor fluvoxamine showed effect over placebo.

CONCLUSIONS

In this randomized, placebo-controlled trial of outpatient treatment of SARS-CoV-2, metformin significantly reduced SARS-CoV-2 viral load, which may explain the clinical benefits in this trial. Metformin is pleiotropic with other actions that are relevant to COVID-19 pathophysiology.

CLINICAL TRIALS REGISTRATION

NCT04510194.

Enhancing Lifestyles in the Metabolic syndrome (ELM) multisite behavioral efficacy trial. Design and baseline cohort

BACKGROUND

Prevalence of metabolic syndrome (MetS) increased from one-quarter to one-third of the U.S. adult population over 8 years and is spreading to young adults and Asian and Hispanic Americans. Diagnosed when >3 out of 5 cardiometabolic risk factors are present, there is widespread agreement that its fundamental roots are in a lifestyle characterized by poor dietary quality and physical inactivity. Past lifestyle trials for MetS produce benefits that have limited sustainability, suggesting the need for new treatment approaches.

METHODS

This is the design and baseline cohort of the Enhancing Lifestyles in the Metabolic Syndrome (ELM) multi-site trial. The trial tests the hypothesis that a habit-based lifestyle treatment offered over 6 months, followed by 18 monthly maintenance contacts, can produce 4 new diet, physical activity, and mindfulness habits and, if so, sustained MetS remission. The design is an individually randomized, partially clustered group treatment trial of 618 participants with the MetS recruited from 5 sites in the U.S. and randomized to a small group lifestyle treatment or an enhanced standard of care education comparator. The primary outcome is MetS remission at 24 months. Secondary outcomes compare arms at 6, 15, and 24 months on MetS components, lifestyle targets, weight, body mass index, hemoglobin A1c, LDL cholesterol, medications, quality of life, psychosocial factors, and cost-effectiveness.

RESULTS

The cohort of 618 participants was recruited by screening 14,817 over 2.5 years (screening to enrollment ratio 24:1). Recruitment exceeded the target of 600 despite 2 COVID-19 pauses. The mean age was 55.5 years, 24.3% were male, 25.5% were a racial minority, 9.7% identified as Hispanic, and 83.0% were classified as obese (body mass index >30). The most common MetS components were abdominal obesity (97.7%) and elevated blood pressure or antihypertensive medication (86.2%).

CONCLUSIONS

The geographic, sociodemographic, and clinical diversity of the cohort, combined with rigorous behavioral efficacy trial methods, will provide a conclusive answer to the question of whether this habit-based lifestyle program can produce sustained 24-month remission of the MetS and thereby help to curb a significant and growing public health problem.

Effectiveness of preconception weight loss interventions on fertility in women: a systematic review and meta-analysis

IMPORTANCE

Weight loss before conception is recommended for women with overweight or obesity to improve fertility outcomes, but evidence supporting this recommendation is mixed.

OBJECTIVE

To examine the effectiveness of weight loss interventions using lifestyle modification and/or medication in women with overweight or obesity on pregnancy, live birth, and miscarriage.

DATA SOURCES

An electronic search of MEDLINE, Embase, Cochrane Library, including Cochrane Database of Systematic Reviews and Cochrane Central Register of Controlled Trials, and Cumulative Index to Nursing and Allied Health Literature was conducted through July 6, 2022, via Wiley.

STUDY SELECTION AND SYNTHESIS

Randomized controlled trials examining weight loss interventions through lifestyle and/or medication in women with overweight or obesity planning pregnancy were included. Random-effects meta-analysis was conducted, reporting the risk ratio (RR) for each outcome. Subgroup analyses were conducted by intervention type, type of control group, fertility treatment, intervention length, and body mass index (BMI).

MAIN OUTCOME(S)

Clinical pregnancy, live birth, and miscarriage events.

RESULT(S)

A narrative review and meta-analysis were possible for 16 studies for pregnancy (n = 3,588), 13 for live birth (n = 3,329), and 11 for miscarriage (n = 3,248). Women randomized and exposed to a weight loss intervention were more likely to become pregnant (RR = 1.24, 95% CI 1.07-1.44; I2 = 59%) but not to have live birth (RR = 1.19, 95% CI 0.97-1.45; I2 = 69%) or miscarriage (RR = 1.17, 95% CI 0.79-1.74; I2 = 31%) compared with women in control groups. Subgroup analyses revealed women randomized to weight loss interventions lasting 12 weeks or fewer (n = 9, RR = 1.43; 95% CI 1.13-1.83) and women with a BMI ≥ 35 kg/m2 (n = 7, RR = 1.54; 95% CI, 1.18-2.02) were more likely to become pregnant compared with women in the control groups. Miscarriage was higher in intervention groups who underwent fertility treatment (n = 8, RR 1.45; 95% CI 1.07-1.96).

CONCLUSION(S)

Pregnancy rates were higher in women undergoing preconception weight loss interventions with no impact on live birth or miscarriage rates. Findings do not support one-size-fits-all recommendation for weight loss through lifestyle modification and/or medication in women with overweight or obesity immediately before conception to improve live birth or miscarriage outcomes.

The Fit After Baby randomized controlled trial: An mHealth postpartum lifestyle intervention for women with elevated cardiometabolic risk

BACKGROUND

Postpartum women with overweight/obesity and a history of adverse pregnancy outcomes are at elevated risk for cardiometabolic disease. Postpartum weight loss and lifestyle changes can decrease these risks, yet traditional face-to-face interventions often fail. We adapted the Diabetes Prevention Program into a theory-based mobile health (mHealth) program called Fit After Baby (FAB) and tested FAB in a randomized controlled trial.

METHODS

The FAB program provided 12 weeks of daily evidence-based content, facilitated tracking of weight, diet, and activity, and included weekly coaching and gamification with points and rewards. We randomized women at 6 weeks postpartum 2:1 to FAB or to the publicly available Text4baby (T4B) app (active control). We measured weight and administered behavioral questionnaires at 6 weeks, and 6 and 12 months postpartum, and collected app user data.

RESULTS

81 eligible women participated (77% White, 2% Asian, 15% Black, with 23% Hispanic), mean baseline BMI 32±5 kg/m2 and age 31±5 years. FAB participants logged into the app a median of 51/84 (IQR 25,71) days, wore activity trackers 66/84 (IQR 43,84) days, logged weight 17 times (IQR 11,24), and did coach check-ins 5.5/12 (IQR 4,9) weeks. The COVID-19 pandemic interrupted data collection for the primary 12-month endpoint, and impacted diet, physical activity, and body weight for many participants. At 12 months postpartum women in the FAB group lost 2.8 kg [95% CI -4.2,-1.4] from baseline compared to a loss of 1.8 kg [95% CI -3.8,+0.3] in the T4B group (p = 0.42 for the difference between groups). In 60 women who reached 12 months postpartum before the onset of the COVID-19 pandemic, women randomized to FAB lost 4.3 kg [95% CI -6.0,-2.6] compared to loss in the control group of 1.3 kg [95% CI -3.7,+1.1] (p = 0.0451 for the difference between groups).

CONCLUSIONS

There were no significant differences between groups for postpartum weight loss for the entire study population. Among those unaffected by the COVID pandemic, women randomized to the FAB program lost significantly more weight than those randomized to the T4B program. The mHealth FAB program demonstrated a substantial level of engagement. Given the scalability and potential public health impact of the FAB program, the efficacy for decreasing cardiometabolic risk by increasing postpartum weight loss should be tested in a larger trial.

Breastfeeding Associated with Lower Prevalence of Metabolic Syndrome in Women with Gestational Diabetes in the Very Early Postpartum Period

OBJECTIVE

 The aim of this study is to examine the association of breastfeeding with metabolic syndrome (MetS) in women with recent gestational diabetes mellitus (GDM) in the very early postpartum (PP) period.

STUDY DESIGN

 We performed a secondary analysis of the Balance After Baby Intervention (BABI) study which enrolled women with recent GDM. Data collected during an early (~8 weeks) PP visit were used in this analysis. At this visit, weight, height, waist circumference (WC), blood pressure (BP), fasting plasma glucose (FPG), and lipids were obtained. MetS was classified per National Cholesterol Education Program Adult Treatment Program III (NCEP-ATP III) criteria. We defined breastfeeding as currently breastfeeding or not currently breastfeeding for the main analysis.

RESULTS

 Of 181 women enrolled in BABI, 178 were included in this analysis (3 excluded for missing lipids). Thirty-four percent were Hispanic. Of non-Hispanics, 31.5% were White, 18.5% Asian, and 12.9% Black/African American. The prevalence of MetS was 42.9% in women not breastfeeding versus 17.1% in women breastfeeding (p < 0.001; adjusted odds ratio [aOR] = 0.16 [95% confidence interval (CI): 0.06-0.41]). Breastfeeding women had significantly lower odds of FPG ≥100 mg/dL (aOR = 0.36 [95% CI: 0.14-0.95], p = 0.039), HDL < 50 mg/dL (aOR = 0.19 [95% CI: 0.08-0.46], p < 0.001), and triglycerides (TG) ≥ 150 mg/dL (aOR = 0.26 [95% CI: 0.10-0.66], p = 0.005). When evaluated as continuous variables, WC, FPG, and TG were significantly lower and HDL significantly higher in women breastfeeding in the very early PP period (vs. not breastfeeding).

CONCLUSION

 In a diverse population of women with recent GDM, there was lower prevalence of MetS in women breastfeeding compared with those not breastfeeding in the very early PP period. This study extends the findings of an association of breastfeeding with MetS previously reported at time points more remote from pregnancy to the very early PP period and to an ethnically and racially diverse population.

KEY POINTS

· MetS prevalence in women with recent GDM was lower in breastfeeding than not breastfeeding women.. · FPG, HDL, WC, and TG were improved in the breastfeeding group.. · This study extends prior findings to the very early PP period and to a diverse population..

Postpartum women's experiences in a randomized controlled trial of a web-based lifestyle intervention following Gestational Diabetes: a qualitative study

INTRODUCTION

Gestational diabetes mellitus (GDM) is associated with an increased maternal risk for the development of type 2 diabetes (T2DM). We previously demonstrated in a randomized trial that a web-based postpartum lifestyle intervention program, Balance After Baby, increased weight loss among postpartum women with recent pregnancies complicated by GDM. The aim of this analysis is to identify the impact of the intervention on study participants as assessed by exit interviews after completion of the 12 month study.

METHODS

We conducted structured exit interviews created with a concurrent-contextual design with subjects randomized to the intervention group at the conclusion of their participation (∼12 months) in the Balance After Baby study, with the objectives of 1) understanding the impact of the intervention on participants and their family members, 2) identifying which program components were most and least helpful, and 3) identifying the perceived best timing for diabetes prevention interventions in postpartum women with recent GDM.

RESULTS

Seventy-nine percent (26/33) of eligible intervention participants participated in interviews. Participants noted changes in diet and physical activity as a result of the intervention. Several components of the intervention, particularly the online modules and support from the lifestyle coach, were perceived by intervention participants to have had a positive effect on personal and familial lifestyle change, while other components were less utilized, including the community forum, YMCA memberships, and pedometers. Nearly all participants felt that the timing in the intervention study, beginning about 6 weeks postpartum, was ideal.

DISCUSSION

Results of this study identify the importance of individualized coaching, impact on family members, and demonstrate that postpartum women feel ready to make changes by 6 weeks postpartum. Findings from this study will help inform the development of future technologically-based lifestyle interventions for postpartum women with recent GDM.

Obesity Management in Adults: A Review

Importance

Obesity affects approximately 42% of US adults and is associated with increased rates of type 2 diabetes, hypertension, cardiovascular disease, sleep disorders, osteoarthritis, and premature death.

Observations

A body mass index (BMI) of 25 or greater is commonly used to define overweight, and a BMI of 30 or greater to define obesity, with lower thresholds for Asian populations (BMI ≥25-27.5), although use of BMI alone is not recommended to determine individual risk. Individuals with obesity have higher rates of incident cardiovascular disease. In men with a BMI of 30 to 39, cardiovascular event rates are 20.21 per 1000 person-years compared with 13.72 per 1000 person-years in men with a normal BMI. In women with a BMI of 30 to 39.9, cardiovascular event rates are 9.97 per 1000 person-years compared with 6.37 per 1000 person-years in women with a normal BMI. Among people with obesity, 5% to 10% weight loss improves systolic blood pressure by about 3 mm Hg for those with hypertension, and may decrease hemoglobin A1c by 0.6% to 1% for those with type 2 diabetes. Evidence-based obesity treatment includes interventions addressing 5 major categories: behavioral interventions, nutrition, physical activity, pharmacotherapy, and metabolic/bariatric procedures. Comprehensive obesity care plans combine appropriate interventions for individual patients. Multicomponent behavioral interventions, ideally consisting of at least 14 sessions in 6 months to promote lifestyle changes, including components such as weight self-monitoring, dietary and physical activity counseling, and problem solving, often produce 5% to 10% weight loss, although weight regain occurs in 25% or more of participants at 2-year follow-up. Effective nutritional approaches focus on reducing total caloric intake and dietary strategies based on patient preferences. Physical activity without calorie reduction typically causes less weight loss (2-3 kg) but is important for weight-loss maintenance. Commonly prescribed medications such as antidepressants (eg, mirtazapine, amitriptyline) and antihyperglycemics such as glyburide or insulin cause weight gain, and clinicians should review and consider alternatives. Antiobesity medications are recommended for nonpregnant patients with obesity or overweight and weight-related comorbidities in conjunction with lifestyle modifications. Six medications are currently approved by the US Food and Drug Administration for long-term use: glucagon-like peptide receptor 1 (GLP-1) agonists (semaglutide and liraglutide only), tirzepatide (a glucose-dependent insulinotropic polypeptide/GLP-1 agonist), phentermine-topiramate, naltrexone-bupropion, and orlistat. Of these, tirzepatide has the greatest effect, with mean weight loss of 21% at 72 weeks. Endoscopic procedures (ie, intragastric balloon and endoscopic sleeve gastroplasty) can attain 10% to 13% weight loss at 6 months. Weight loss from metabolic and bariatric surgeries (ie, laparoscopic sleeve gastrectomy and Roux-en-Y gastric bypass) ranges from 25% to 30% at 12 months. Maintaining long-term weight loss is difficult, and clinical guidelines support the use of long-term antiobesity medications when weight maintenance is inadequate with lifestyle interventions alone.

Conclusion and Relevance

Obesity affects approximately 42% of adults in the US. Behavioral interventions can attain approximately 5% to 10% weight loss, GLP-1 agonists and glucose-dependent insulinotropic polypeptide/GLP-1 receptor agonists can attain approximately 8% to 21% weight loss, and bariatric surgery can attain approximately 25% to 30% weight loss. Comprehensive, evidence-based obesity treatment combines behavioral interventions, nutrition, physical activity, pharmacotherapy, and metabolic/bariatric procedures as appropriate for individual patients.

Strategies used for the COVID-OUT decentralized trial of outpatient treatment of SARS-CoV-2

The COVID-19 pandemic accelerated the development of decentralized clinical trials (DCT). DCT's are an important and pragmatic method for assessing health outcomes yet comprise only a minority of clinical trials, and few published methodologies exist. In this report, we detail the operational components of COVID-OUT, a decentralized, multicenter, quadruple-blinded, randomized trial that rapidly delivered study drugs nation-wide. The trial examined three medications (metformin, ivermectin, and fluvoxamine) as outpatient treatment of SARS-CoV-2 for their effectiveness in preventing severe or long COVID-19. Decentralized strategies included HIPAA-compliant electronic screening and consenting, prepacking investigational product to accelerate delivery after randomization, and remotely confirming participant-reported outcomes. Of the 1417 individuals with the intention-to-treat sample, the remote nature of the study caused an additional 94 participants to not take any doses of study drug. Therefore, 1323 participants were in the modified intention-to-treat sample, which was the a priori primary study sample. Only 1.4% of participants were lost to follow-up. Decentralized strategies facilitated the successful completion of the COVID-OUT trial without any in-person contact by expediting intervention delivery, expanding trial access geographically, limiting contagion exposure, and making it easy for participants to complete follow-up visits. Remotely completed consent and follow-up facilitated enrollment.

Outpatient treatment of COVID-19 and incidence of post-COVID-19 condition over 10 months (COVID-OUT): a multicentre, randomised, quadruple-blind, parallel-group, phase 3 trial

BACKGROUND

Post-COVID-19 condition (also known as long COVID) is an emerging chronic illness potentially affecting millions of people. We aimed to evaluate whether outpatient COVID-19 treatment with metformin, ivermectin, or fluvoxamine soon after SARS-CoV-2 infection could reduce the risk of long COVID.

METHODS

We conducted a decentralised, randomised, quadruple-blind, parallel-group, phase 3 trial (COVID-OUT) at six sites in the USA. We included adults aged 30-85 years with overweight or obesity who had COVID-19 symptoms for fewer than 7 days and a documented SARS-CoV-2 positive PCR or antigen test within 3 days before enrolment. Participants were randomly assigned via 2 × 3 parallel factorial randomisation (1:1:1:1:1:1) to receive metformin plus ivermectin, metformin plus fluvoxamine, metformin plus placebo, ivermectin plus placebo, fluvoxamine plus placebo, or placebo plus placebo. Participants, investigators, care providers, and outcomes assessors were masked to study group assignment. The primary outcome was severe COVID-19 by day 14, and those data have been published previously. Because the trial was delivered remotely nationwide, the a priori primary sample was a modified intention-to-treat sample, meaning that participants who did not receive any dose of study treatment were excluded. Long COVID diagnosis by a medical provider was a prespecified, long-term secondary outcome. This trial is complete and is registered with ClinicalTrials.gov, NCT04510194.

FINDINGS

Between Dec 30, 2020, and Jan 28, 2022, 6602 people were assessed for eligibility and 1431 were enrolled and randomly assigned. Of 1323 participants who received a dose of study treatment and were included in the modified intention-to-treat population, 1126 consented for long-term follow-up and completed at least one survey after the assessment for long COVID at day 180 (564 received metformin and 562 received matched placebo; a subset of participants in the metformin vs placebo trial were also randomly assigned to receive ivermectin or fluvoxamine). 1074 (95%) of 1126 participants completed at least 9 months of follow-up. 632 (56·1%) of 1126 participants were female and 494 (43·9%) were male; 44 (7·0%) of 632 women were pregnant. The median age was 45 years (IQR 37-54) and median BMI was 29·8 kg/m2 (IQR 27·0-34·2). Overall, 93 (8·3%) of 1126 participants reported receipt of a long COVID diagnosis by day 300. The cumulative incidence of long COVID by day 300 was 6·3% (95% CI 4·2-8·2) in participants who received metformin and 10·4% (7·8-12·9) in those who received identical metformin placebo (hazard ratio [HR] 0·59, 95% CI 0·39-0·89; p=0·012). The metformin beneficial effect was consistent across prespecified subgroups. When metformin was started within 3 days of symptom onset, the HR was 0·37 (95% CI 0·15-0·95). There was no effect on cumulative incidence of long COVID with ivermectin (HR 0·99, 95% CI 0·59-1·64) or fluvoxamine (1·36, 0·78-2·34) compared with placebo.

INTERPRETATION

Outpatient treatment with metformin reduced long COVID incidence by about 41%, with an absolute reduction of 4·1%, compared with placebo. Metformin has clinical benefits when used as outpatient treatment for COVID-19 and is globally available, low-cost, and safe.

FUNDING

Parsemus Foundation; Rainwater Charitable Foundation; Fast Grants; UnitedHealth Group Foundation; National Institute of Diabetes, Digestive and Kidney Diseases; National Institutes of Health; and National Center for Advancing Translational Sciences.

Carbohydrate Intake and Oral Glucose Tolerance Test Results in the Postpartum Period

CONTEXT

The American Diabetes Association (ADA) recommends a 3-day preparatory diet prior to a diagnostic oral glucose tolerance test (OGTT), a test often recommended in postpartum individuals with a history of gestational diabetes (GDM).

OBJECTIVE

Evaluate the relationship between carbohydrate intake and OGTT glucose in 2 cohorts of postpartum individuals.

METHODS

We performed analyses of postpartum individuals from 2 prospective studies with recent GDM (Balance after Baby Intervention, BABI, n = 177) or risk factors for GDM (Study of Pregnancy Regulation of INsulin and Glucose, SPRING, n = 104) .We measured carbohydrate intake using 24-hour dietary recalls (SPRING) or Food Frequency Questionnaire (BABI) and performed 2-hour 75-g OGTTs. The main outcome measure was 120-minute post-OGTT glucose.

RESULTS

There was no relationship between carbohydrate intake and 120-minute post-OGTT glucose level in either study population (SPRING: β = 0.03, [-5.5, 5.5] mg/dL, P = .99; BABI: β = -3.1, [-9.5, 3.4] mg/dL, P = .35). Adding breastfeeding status to the model did not change results (SPRING β = -0.14, [-5.7, 5.5] mg/dL, P = .95; BABI β = -3.9, [-10.4, 2.7] mg/dL, P = .25). There was, however, an inverse relationship between glycemic index and 120-minute post OGTT glucose (BABI: β = -1.1, [-2.2, -0.03] mg/dL, P = .04).

CONCLUSION

Carbohydrate intake is not associated with post-OGTT glucose levels among postpartum individuals. Dietary preparation prior to the OGTT may not be necessary in this population.

Effectiveness of the National Diabetes Prevention Program After Gestational Diabetes

INTRODUCTION

Women with previous gestational diabetes are at high risk of developing Type 2 diabetes. The National Diabetes Prevention Program (NDPP) is a widely disseminated lifestyle intervention to prevent Type 2 diabetes. Although NDPP programs are open to adults of any age, participants are usually older adults. Effectiveness among younger women with previous gestational diabetes is largely unknown.

METHODS

The NDPP was delivered by lifestyle coaches in a large network of Federally Qualified Health Centers. Reach, retention, physical activity, and weight loss outcomes were compared between women aged <40 years with previous gestational diabetes and all other participants. Data were collected from 2013 to 2019 and analyzed in 2022.

RESULTS

Among 2,865 enrollees who agreed to start the yearlong NDPP, 63.3% were Latinx, 18.8% were non-Latinx Black, and 16.4% were non-Latinx White. Younger women with previous gestational diabetes represented <4% (n=107) of participants. There was no significant difference in the frequency of attending ≥1 NDPP session between these women and all other participants (37.4% vs 44.6%; p=0.146). However, among those attending ≥1 session (n=1,265), younger women with previous gestational diabetes attended more (11.27 ± 1.27 vs 8.50 ± 0.22 sessions, p=0.021) and had greater weight loss (3.04% ± 0.59 vs. 1.49% ± 0.11, p=0.010) in covariate-adjusted models than other participants.

CONCLUSIONS

Diverse younger women with previous gestational diabetes attending the NDPP had one third greater attendance and twice as much weight loss as other NDPP participants but represented a much smaller proportion of enrollees. Thus, the NDPP appears to be a beneficial but underutilized resource for this high-risk population.

Metformin reduces SARS-CoV-2 in a Phase 3 Randomized Placebo Controlled Clinical Trial

Current antiviral treatment options for SARS-CoV-2 infections are not available globally, cannot be used with many medications, and are limited to virus-specific targets.1-3 Biophysical modeling of SARS-CoV-2 replication predicted that protein translation is an especially attractive target for antiviral therapy.4 Literature review identified metformin, widely known as a treatment for diabetes, as a potential suppressor of protein translation via targeting of the host mTor pathway.5 In vitro, metformin has antiviral activity against RNA viruses including SARS-CoV-2.6,7 In the COVID-OUT phase 3, randomized, placebo-controlled trial of outpatient treatment of COVID-19, metformin had a 42% reduction in ER visits/hospitalizations/death through 14 days; a 58% reduction in hospitalizations/death through 28 days, and a 42% reduction in Long COVID through 10 months.8,9 Here we show viral load analysis of specimens collected in the COVID-OUT trial that the mean SARS-CoV-2 viral load was reduced 3.6-fold with metformin relative to placebo (-0.56 log10 copies/mL; 95%CI, -1.05 to -0.06, p=0.027) while there was no virologic effect for ivermectin or fluvoxamine vs placebo. The metformin effect was consistent across subgroups and with emerging data.10,11 Our results demonstrate, consistent with model predictions, that a safe, widely available,12 well-tolerated, and inexpensive oral medication, metformin, can be repurposed to significantly reduce SARS-CoV-2 viral load.

A WIC-Based Behavior Change Intervention for Postpartum Women With Overweight and Obesity: A Pilot Feasibility Randomized Trial

Background. Postpartum weight retention is a risk factor for obesity and is particularly important among Hispanic women who have an increased rate of obesity. Given its broad reach, the Special Supplemental Nutrition Program for Women, Infants, and Children (WIC) program provides an ideal setting to implement community-based interventions for low-income postpartum women. Purpose. To examine the feasibility, acceptability, and preliminary efficacy of a multicomponent intervention delivered by staff within the WIC program designed to promote behavior changes in urban, postpartum women with overweight/obesity. Method. This was a 12-week pilot trial randomizing participants to a health behavior change (Intervention) or control (Observation) group. The Intervention included monthly visits with trained WIC staff providing patient-centered behavior change counseling, with multiple touchpoints between visits promoting self-monitoring and offering health behavior change support. Results. Participants (n = 41), who were mainly Hispanic (n = 37, 90%) and Spanish-speaking (n = 33, 81%), were randomized to the Intervention (n = 19) or Observation (n = 22) group. In the Intervention group, 79% (n = 15) of eligible participants were retained for the study duration. All Intervention participants endorsed that they would participate again. Regarding physical activity, participant readiness to change and self-efficacy improved for Intervention participants. About one-quarter of women in the Intervention group (27%, n = 4) had a 5% weight loss compared with one woman (5%) in the Observation group; this difference was not statistically significant (p = .10). Conclusions. This pilot demonstrated the feasibility and acceptability of delivering a low-intensity behavior change intervention within the WIC setting for postpartum women with overweight/obesity. Findings support the role of WIC in addressing postpartum obesity.

Self-Efficacy and Readiness to Change Among Women with Recent Gestational Diabetes Engaging in a Web-Based Lifestyle Intervention: The Balance After Baby Intervention Trial

Few evidence-based programs exist to help women with a history of gestational diabetes reduce their risk of developing type 2 diabetes. In secondary analyses from a randomized clinical trial of a web-based lifestyle intervention program for postpartum women with recent gestational diabetes, we studied changes in self-efficacy for diet and physical activity and readiness to change health behaviors. Women were randomized at ∼6 weeks postpartum and completed questionnaires at 6 weeks and 6, 12, 18, and 24 months. Our study included 181 women (mean age 32.4 ± 5.2 years; 48% White, 19% Asian, 14% Black or African American, 17% other/mixed race; 34% Hispanic). In a linear mixed effects model, women in the intervention had significantly greater improvement in overall self-efficacy scores for physical activity compared with the control group at 24 months (difference in change scores between groups .35, 95% CI: .03 to .67, P = .03). The intervention group also demonstrated significantly greater improvement in self-efficacy scores for both physical activity subdomains, specifically “sticking to it” at 24 months and “making time” at 12 months. Participants in the intervention did not experience a significant difference in change in self-efficacy for diet or readiness to change compared with those in the control arm.

Impact of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) Vaccination and Booster on Coronavirus Disease 2019 (COVID-19) Symptom Severity Over Time in the COVID-OUT Trial

BACKGROUND

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination has decreasing protection from acquiring any infection with emergence of new variants; however, vaccination continues to protect against progression to severe coronavirus disease 2019 (COVID-19). The impact of vaccination status on symptoms over time is less clear.

METHODS

Within a randomized trial on early outpatient COVID-19 therapy testing metformin, ivermectin, and/or fluvoxamine, participants recorded symptoms daily for 14 days. Participants were given a paper symptom diary allowing them to circle the severity of 14 symptoms as none (0), mild (1), moderate (2), or severe (3). This is a secondary analysis of clinical trial data on symptom severity over time using generalized estimating equations comparing those unvaccinated, SARS-CoV-2 vaccinated with primary vaccine series only, or vaccine-boosted.

RESULTS

The parent clinical trial prospectively enrolled 1323 participants, of whom 1062 (80%) prospectively recorded some daily symptom data. Of these, 480 (45%) were unvaccinated, 530 (50%) were vaccinated with primary series only, and 52 (5%) vaccine-boosted. Overall symptom severity was least for the vaccine-boosted group and most severe for unvaccinated at baseline and over the 14 days (P < .001). Individual symptoms were least severe in the vaccine-boosted group including cough, chills, fever, nausea, fatigue, myalgia, headache, and diarrhea, as well as smell and taste abnormalities. Results were consistent over Delta and Omicron variant time periods.

CONCLUSIONS

SARS-CoV-2 vaccine-boosted participants had the least severe symptoms during COVID-19, which abated the quickest over time. Clinical Trial Registration. NCT04510194.

Randomized Trial of Metformin, Ivermectin, and Fluvoxamine for Covid-19

BACKGROUND

Early treatment to prevent severe coronavirus disease 2019 (Covid-19) is an important component of the comprehensive response to the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic.

METHODS

In this phase 3, double-blind, randomized, placebo-controlled trial, we used a 2-by-3 factorial design to test the effectiveness of three repurposed drugs - metformin, ivermectin, and fluvoxamine - in preventing serious SARS-CoV-2 infection in nonhospitalized adults who had been enrolled within 3 days after a confirmed diagnosis of infection and less than 7 days after the onset of symptoms. The patients were between the ages of 30 and 85 years, and all had either overweight or obesity. The primary composite end point was hypoxemia (≤93% oxygen saturation on home oximetry), emergency department visit, hospitalization, or death. All analyses used controls who had undergone concurrent randomization and were adjusted for SARS-CoV-2 vaccination and receipt of other trial medications.

RESULTS

A total of 1431 patients underwent randomization; of these patients, 1323 were included in the primary analysis. The median age of the patients was 46 years; 56% were female (6% of whom were pregnant), and 52% had been vaccinated. The adjusted odds ratio for a primary event was 0.84 (95% confidence interval [CI], 0.66 to 1.09; P = 0.19) with metformin, 1.05 (95% CI, 0.76 to 1.45; P = 0.78) with ivermectin, and 0.94 (95% CI, 0.66 to 1.36; P = 0.75) with fluvoxamine. In prespecified secondary analyses, the adjusted odds ratio for emergency department visit, hospitalization, or death was 0.58 (95% CI, 0.35 to 0.94) with metformin, 1.39 (95% CI, 0.72 to 2.69) with ivermectin, and 1.17 (95% CI, 0.57 to 2.40) with fluvoxamine. The adjusted odds ratio for hospitalization or death was 0.47 (95% CI, 0.20 to 1.11) with metformin, 0.73 (95% CI, 0.19 to 2.77) with ivermectin, and 1.11 (95% CI, 0.33 to 3.76) with fluvoxamine.

CONCLUSIONS

None of the three medications that were evaluated prevented the occurrence of hypoxemia, an emergency department visit, hospitalization, or death associated with Covid-19. (Funded by the Parsemus Foundation and others; COVID-OUT ClinicalTrials.gov number, NCT04510194.).

Breastfeeding Is Associated With Lower Prevalence of Metabolic Syndrome in Women With Recent Gestational Diabetes in the Early Postpartum Period

Introduction: Women with gestational diabetes (GD) are at increased risk of future cardiovascular disease. The identification of factors that reduce metabolic syndrome (MetS) is important to improve cardiovascular outcomes. MetS has been shown to be associated with breastfeeding in women remote from pregnancy. We examined the association of breastfeeding with MetS in women with recent GD in the very early postpartum (pp) period. Methods: We performed a secondary analysis of the Balance After Baby (BAB) program which enrolled women with recent GD. GD was defined by Carpenter-Coustan criteria, a 50 gram glucose load test &gt;200 mg/dL or by clinician diagnosis. Data collected during an early (~6 weeks) pp visit was used in this analysis. At this visit, weight, height, waist circumference (WC), blood pressure (BP), fasting plasma glucose (FPG) and lipid panel were obtained. MetS was classified per NCEP III. We defined breastfeeding as currently breastfeeding or not currently breastfeeding. We performed Student’s t-tests and Wilcoxon rank-sum tests as appropriate, and fit logistic and linear regression models. Models were adjusted for age, race/ethnicity, low household income, pre-pregnancy BMI, and weeks since delivery. An exploratory model further adjusted for postpartum weight retention. Results: Of 181 women enrolled in BAB, 178 were included in this analysis (3 excluded for missing lipid panels). The mean (± SD) age of participants was 33 ± 5 years and were 8.0 ± 1.8 weeks since delivery. Thirty-four % were Hispanic. Of non-Hispanics, 31.5% were White, 18.5% Asian and 12.9% Black/African American. The prevalence of MetS was 42.9% in women not breastfeeding versus 17.1% in women breastfeeding (P &lt; 0.001; adjusted odds ratio [aOR] 0.16 [95% CI 0.06–0.41]). Breastfeeding women had significantly lower odds of FPG ≥100 mg/dL (aOR 0.36 [95% CI 0.14–0.95], p=0.039), HDL &lt;50 mg/dL (aOR 0.19 [95% CI 0.08–0.46], p&lt;0.001), and triglycerides (TG) ≥150 mg/dL (aOR 0.26 [95% CI 0.10–0.66], p=0.005). There was no significant difference in WC or BP between groups. All ORs remained significant after adjusting for weight retention. When evaluated as continuous variables, WC, FPG, and TG were significantly lower and HDL significantly higher in women breastfeeding in the early pp period (vs not breastfeeding). Conclusion: In a diverse population of women with recent GD, there was a lower prevalence of MetS in women breastfeeding compared to those not breastfeeding in the early postpartum period. This study extends the findings of an association of breastfeeding with MetS previously reported at times remote from pregnancy. Further studies are needed to determine if there is a protective role of breastfeeding on the risk of MetS.

Cardiovascular Health After Preeclampsia: Patient and Provider Perspective

Background: Preeclampsia predicts future cardiovascular disease (CVD) yet few programs exist for post-preeclampsia care. Methods: The Health after Preeclampsia Patient and Provider Engagement Network workshop was convened at the Radcliffe Institute for Advanced Study in June 2018. The workshop sought to identify: 1) patient perspectives on barriers and facilitators to CVD risk reduction; 2) clinical programs specialized in post-preeclampsia care; 3) recommendations by national organizations for risk reduction; and 4) next steps. Stakeholders included the Preeclampsia Foundation, patients, clinicians who had initiated CVD risk reduction programs for women with prior preeclampsia, researchers, and national task force members. Results: Participants agreed there is insufficient awareness and action to prevent CVD after preeclampsia. Patients suggested a clinician checklist to ensure communication of CVD risks, enhanced training for clinicians on the link between preeclampsia and CVD, and a post-delivery appointment with a clinician knowledgeable about this link. Clinical programs primarily served patients in the first postpartum year, bridging obstetrical and primary care. They recommended CVD risk modification with periodic blood pressure, weight, lipid and diabetes screening. Barriers included the paucity of programs designed for this population and gaps in insurance coverage after delivery. The American Heart Association, the American College of Obstetricians and Gynecologists, and the Preeclampsia Foundation have developed guidelines and materials for patients and providers to guide management of women with prior preeclampsia. Conclusions: Integrated efforts of patients, caregivers, researchers, and national organizations are needed to improve CVD prevention after preeclampsia. This meeting's recommendations can serve as a resource and catalyst for this effort.

OR08-03 Association of Hemoglobin A1c with Early Postpartum Metabolic Syndrome in Women with Gestational Diabetes

Background: Women with gestational diabetes (GDM) are at increased risk of metabolic syndrome (MetS), an important risk factor for development of type 2 diabetes (T2DM) and cardiovascular disease. Elevated hemoglobin A1c (HbA1c) is associated with MetS outside of pregnancy and may enhance detection of MetS. It is not known whether HbA1c is associated with MetS in the early postpartum period in women with recent GDM.

Objective: We aimed to characterize the prevalence of MetS 4-12 weeks postpartum in women with recent GDM and to determine whether there was an association between HbA1c and MetS.

Methods: Women with GDM as defined by Carpenter-Coustan criteria or clinician diagnosis were enrolled into the Balance After Baby Intervention trial of a web-based intervention to prevent T2DM. They underwent a baseline study visit at 4-12 weeks postpartum. Waist circumference and blood pressure were obtained and a fasting lipid panel, HbA1c and a 75-g, 2 hr OGTT was performed. We defined MetS by NCEP ATP III criteria. We fit a logistic regression model adjusted for age, race/ethnicity, and number of weeks postpartum.

Results: 181 women with GDM were enrolled in the study. Three women were excluded because they did not have fasting lipid measurements. Women were a mean of 8.0 ± 1.8 weeks postpartum at their baseline study visit. 24.2% (n=43) of women had MetS (at least 3 of 5 NCEP ATP III criteria). Of these, 77% met the waist circumference criterion, 37.6% met the HDL criterion, 23.6% met the triglycerides criterion, 16.9% met the fasting glucose criterion and 14.6% met the blood pressure criterion. HbA1c as a continuous variable was not significantly associated with MS (OR for each 0.5% increase: 1.60, 95% CI 0.88-2.91). Elevated HbA1c (prediabetes range ≥5.7 to <6.5%) was also not associated with MetS (OR 0.98, 95% CI 0.46-2.12). A 2 hr blood glucose value of ≥140 mg/dL on OGTT testing was significantly associated with MetS (OR 5.28, 95% CI 2.11-13.22).

Conclusion: Nearly 1 in 4 women with recent GDM had MetS in the early postpartum period. There was no significant association between HbA1c and presence of MetS. However, an elevated 2 hr value on OGTT was significantly associated with MetS, suggesting that women with elevated 2 hr values may require additional monitoring for MetS and may have elevated cardiometabolic risk beyond the risk of development of T2DM.

Development and Modification of a Mobile Health Program to Promote Postpartum Weight Loss in Women at Elevated Risk for Cardiometabolic Disease: Single-Arm Pilot Study

BACKGROUND

Pregnancy complications in combination with postpartum weight retention lead to significant risks of cardiometabolic disease and obesity. The majority of traditional face-to-face interventions have not been effective in postpartum women. Mobile technology enables the active engagement of postpartum women to promote lifestyle changes to prevent chronic diseases.

OBJECTIVE

We sought to employ an interactive, user-centered, and participatory method of development, evaluation, and iteration to design and optimize the mobile health (mHealth) Fit After Baby program.

METHODS

For the initial development, a multidisciplinary team integrated evidence-based approaches for health behavior, diet and physical activity, and user-centered design and engagement. We implemented an iterative feedback and design process via 3 month-long beta pilots in which postpartum women with cardiometabolic risk factors participated in the program and provided weekly and ongoing feedback. We also conducted two group interviews using a structured interview guide to gather additional feedback. Qualitative data were recorded, transcribed, and analyzed using established qualitative methods. Modifications based on feedback were integrated into successive versions of the app.

RESULTS

We conducted three pilot testing rounds with a total of 26 women. Feedback from each pilot cohort informed changes to the functionality and content of the app, and then a subsequent pilot group participated in the program. We optimized the program in response to feedback through three iterations leading to a final version.

CONCLUSIONS

This study demonstrates the feasibility of using an interactive, user-centered, participatory method of rapid, iterative design and evaluation to develop and optimize a mHealth intervention program for postpartum women.

TRIAL REGISTRATION

ClinicalTrials.gov NCT02384226; https://www.clinicaltrials.gov/ct2/show/NCT02384226.

Predictors of very early postpartum weight loss in women with recent gestational diabetes mellitus

Objective: Women with gestational diabetes (GDM) have a 7-12-fold increased risk for developing type 2 diabetes later in life. Postpartum weight retention is highly predictive for future obesity, and further increases risk for type 2 diabetes. We sought to identify predictors of losing at least 75% of gestational weight gain by very early postpartum in women with recent GDM.Methods: We recruited women with GDM during pregnancy or just after delivery. Prepregnancy weight was self-reported at recruitment; gestational weight gain, mode of delivery, and insulin use were extracted from medical records. At a mean of 7.2 (±2.1) weeks postpartum we measured weight and height and administered questionnaires, including demographics, breastfeeding, Edinburgh Postnatal Depression Scale, sleep, Harvard Food Frequency, and the International Physical Activity Questionnaire. We modeled the odds of 75% loss of gestational weight gain at the study visit using multivariable logistic regression models and selected the model with the lowest Akaike information criterion (AIC) as our final model. Analyses were conducted using JMP 10-13 Pro (SAS Institute Inc.)Results: Seventy-five women with recent GDM were included in the study. The mean age of study participants was 33 (SD ±5) years old, of whom 57% were white, 30% were African American, and 20% of the women identified as Hispanic. The mean prepregnancy BMI was 31.4 kg/m2 (SD ±5.6) and the mean pregnancy weight gain was 12.5 kg (SD ±7.8). Fifty-two percent of participants lost at least 75% of their pregnancy weight gain by the early postpartum study visit. Thirty-seven women (49%) exceeded Institute of Medicine (IOM) guidelines for gestational weight gain. In a multivariate model adjusting for weeks postpartum at the time of the study visit, less gestational weight gain (OR 0.56; 95% CI 0.39-0.73), increased age (OR 1.48; 95% CI 1.13-2.20), and lack of insulin use during pregnancy (OR 0.08 for use of insulin; 95% CI 0.00-0.73) were associated with at least 75% postpartum weight loss. Prepregnancy BMI and sleep were not retained in the model. Race/ethnicity, education, breastfeeding, nulliparity, cesarean section, depressive symptoms, dietary composition, glycemic index, and physical activity did not meet criteria for inclusion in the model.Conclusions: A substantial proportion of women with recent GDM lost at least 75% of their gestational weight gain by early postpartum. Older women, those who did not use insulin during pregnancy and those who gained less weight during pregnancy were significantly more likely to have lost 75% of gestational weight by very early postpartum.

Association Between Changes in Postpartum Weight and Waist Circumference and Changes in Cardiometabolic Risk Factors Among Women With Recent Gestational Diabetes

INTRODUCTION

Women with gestational diabetes mellitus (GDM) have a 30% to 70% risk for developing type 2 diabetes and are at increased risk for cardiovascular disease. Little is known about how anthropometric changes in the first postpartum year modify cardiometabolic risk factors.

METHODS

We randomly assigned women in the Balance After Baby study to an intervention group consisting of participation in a web-based lifestyle program or to a control group in which no program was offered. We measured weight, height, waist circumference, blood pressure, lipids, insulin, adiponectin, interleukin-6, and high-sensitivity C-reactive protein, and we conducted 2-hour oral glucose tolerance tests at 6 weeks, 6 months, and 12 months postpartum. We evaluated whether women assigned to the intervention had improved cardiometabolic risk markers compared with the control group. We then conducted a post-hoc analysis, pooling the 2 groups to compare changes in weight and waist circumference with changes in cardiometabolic risk factors.

RESULTS

Women in the intervention group did not significantly improve cardiometabolic risk markers compared with women in the control group. We noted a large overlap of weight change and change in waist circumference between groups. In our post-hoc analysis pooling groups, changes in diabetes and cardiovascular risk factors were significantly correlated with changes in weight and waist circumference. The strongest associations were observed for fasting insulin, HOMA, and fasting glucose.

CONCLUSION

Anthropometric changes in weight and waist circumference in women with recent GDM may affect cardiometabolic risk factors, even in the first postpartum year. Our study demonstrates the importance of the postpartum year as an opportunity to decrease future risk for diabetes and cardiovascular disease in women with a history of GDM.

Patterns of gestational diabetes diagnosis inside and outside of clinical guidelines

Background

Hospital discharge codes are often used to determine the incidence of gestational diabetes mellitus (GDM) at state and national levels. Previous studies demonstrate substantial variability in the accuracy of GDM reporting, and rarely report how the GDM was diagnosed. Our aim was to identify deliveries coded as gestational diabetes, and then to determine how the diagnosis was assigned and whether the diagnosis followed established guidelines.

Methods

We identified which deliveries were coded at discharge as complicated by GDM at the Brigham and Women’s Hospital in Boston, MA for the year 2010. We reviewed medical records to determine whether the codes were appropriately assigned.

Results

Of 7883 deliveries, coding for GDM was assigned with 98% accuracy. We identified 362 cases assigned GDM delivery codes, of which 210 (58%) had oral glucose tolerance test (OGTT) results available meeting established criteria. We determined that 126 cases (34%) received a GDM delivery code due to a clinician diagnosis documented in the medical record, without an OGTT result meeting established guidelines for GDM diagnosis. We identified only 15 cases (4%) that were coding errors.

Conclusions

Thirty four percent of women assigned GDM delivery codes at discharge had a medical record diagnosis of GDM but did not meet OGTT criteria for GDM by established guidelines. Although many of these patients may have met guidelines if guideline-based testing had been conducted, our findings suggest that clinician diagnosis outside of published guidelines may be common. There are many ramifications of this approach to diagnosis, including affecting population-level statistics of GDM prevalence and the potential impact on some women who may be diagnosed with GDM erroneously.

Employing a Multi-level Approach to Recruit a Representative Sample of Women with Recent Gestational Diabetes Mellitus into a Randomized Lifestyle Intervention Trial

OBJECTIVE

The postpartum period is a window of opportunity for diabetes prevention in women with recent gestational diabetes (GDM), but recruitment for clinical trials during this period of life is a major challenge.

METHODS

We adapted a social-ecologic model to develop a multi-level recruitment strategy at the macro (high or institutional level), meso (mid or provider level), and micro (individual) levels. Our goal was to recruit 100 women with recent GDM into the Balance after Baby randomized controlled trial over a 17-month period. Participants were asked to attend three in-person study visits at 6 weeks, 6, and 12 months postpartum. They were randomized into a control arm or a web-based intervention arm at the end of the baseline visit at six weeks postpartum. At the end of the recruitment period, we compared population characteristics of our enrolled subjects to the entire population of women with GDM delivering at Brigham and Women's Hospital (BWH).

RESULTS

We successfully recruited 107 of 156 (69 %) women assessed for eligibility, with the majority (92) recruited during pregnancy at a mean 30 (SD ± 5) weeks of gestation, and 15 recruited postpartum, at a mean 2 (SD ± 3) weeks postpartum. 78 subjects attended the initial baseline visit, and 75 subjects were randomized into the trial at a mean 7 (SD ± 2) weeks postpartum. The recruited subjects were similar in age and race/ethnicity to the total population of 538 GDM deliveries at BWH over the 17-month recruitment period.

CONCLUSIONS

Our multilevel approach allowed us to successfully meet our recruitment goal and recruit a representative sample of women with recent GDM. We believe that our most successful strategies included using a dedicated in-person recruiter, integrating recruitment into clinical flow, allowing for flexibility in recruitment, minimizing barriers to participation, and using an opt-out strategy with providers. Although the majority of women were recruited while pregnant, women recruited in the early postpartum period were more likely to present for the first study visit. Given the increased challenges of recruiting postpartum women with GDM into research studies, we believe our findings will be useful to other investigators seeking to study this population.

Identifying postpartum intervention approaches to reduce cardiometabolic risk among American Indian women with prior gestational diabetes, Oklahoma, 2012-2013

Introduction

Innovative approaches are needed to reduce cardiometabolic risk among American Indian women with a history of gestational diabetes. We assessed beliefs of Oklahoma American Indian women about preventing type 2 diabetes and cardiovascular disease after having gestational diabetes. We also assessed barriers and facilitators to healthy lifestyle changes postpartum and intervention approaches that facilitate participation in a postpartum lifestyle program.

Methods

In partnership with a tribal health system, we conducted a mixed-method study with American Indian women aged 19 to 45 years who had prior gestational diabetes, using questionnaires, focus groups, and individual interviews. Questionnaires were used to identify women’s cardiometabolic risk perceptions and feasibility and acceptability of Internet or mobile phone technology for delivery of a postpartum lifestyle modification program. Focus groups and individual interviews were conducted to identify key perspectives and preferences related to a potential program.

Results

Participants were 26 women, all of whom completed surveys; 11 women participated in focus group sessions, and 15 participated in individual interviews. Most women believed they would inevitably develop diabetes, cardiovascular disease, or both; however, they were optimistic that they could delay onset with lifestyle change. Most women expressed enthusiasm for a family focused, technology-based intervention that emphasizes the importance of delaying disease onset, provides motivation, and promotes accountability while accommodating women’s competing priorities.

Conclusions

Our findings suggest that an intervention that uses the Internet, text messaging, or both and that emphasizes the benefits of delaying disease onset should be tested as a novel, culturally relevant approach to reducing rates of diabetes and cardiovascular disease in this high-risk population.

Optimizing Weight for Maternal and Infant Health - Tenable, or Too Late?

Obesity in pregnancy is the leading cause of maternal and fetal morbidity, and gestational weight gain (GWG) is one modifiable risk factor that improves pregnancy outcomes. Most pregnant women gain more than the 2009 Institute of Medicine recommendations, particularly overweight and obese women. GWG even less than the 2009 IOM guidelines in obese women may improve pregnancy outcomes and reduce large-for-gestational-age (LGA) infants, an independent risk factor for childhood obesity, without increasing small-for-gestational-age (SGA) infants. Unfortunately, despite the fact that over 50 interventional trials designed to decrease excess GWG have been conducted, these interventions have been only modestly effective, and interventions designed to facilitate weight postpartum weight loss have also been disappointing. Successful interventions are of paramount importance not only to improve pregnancy outcomes but also for the future metabolic health of the mother and her infant, and may be key in attenuating the trans-generational risk on childhood obesity.

Risk of future cardiovascular disease in women with prior preeclampsia: a focus group study

BACKGROUND

A history of preeclampsia is a risk factor for the future development of hypertension and cardiovascular disease (CVD). The objective of this study was to assess, in women with prior preeclampsia, the level of knowledge regarding the link between preeclampsia and CVD, motivators for and barriers to lifestyle change and interest in a lifestyle modification program to decrease CVD risk following a pregnancy complicated by preeclampsia.

METHODS

Twenty women with a history of preeclampsia participated in 5 phone-based focus groups. Focus groups were recorded, transcribed, and analyzed. Qualitative content analysis was used to identify common themes across focus groups. Consensus was reached on a representative set of themes describing the data.

RESULTS

Women with prior preeclampsia were in general unaware of the link between preeclampsia and future CVD but eager to learn about this link and motivated to achieve a healthy lifestyle. Major perceived barriers to lifestyle change were lack of time, cost of healthy foods and family responsibilities. Perceived facilitators included knowledge of the link between preeclampsia and CVD, a desire to stay healthy, and creating a healthy home for their children. Women with prior preeclampsia were interested in the idea of a web-based program focused on lifestyle strategies to decrease CVD risk in women.

CONCLUSIONS

Women with prior preeclampsia were eager to learn about the link between preeclampsia and CVD and to take steps to reduce CVD risk. A web-based program to help women with prior preeclampsia adopt a healthy lifestyle may be an appropriate strategy for this population.

Effect of dietary composition of weight loss diets on high-sensitivity c-reactive protein: the Randomized POUNDS LOST trial

OBJECTIVE

Overweight and obesity are associated with increased high-sensitivity C-reactive protein (hsCRP) levels. The purpose of this study was to determine if weight loss diets differing in fat, protein, or carbohydrate composition differentially reduce hsCRP.

DESIGN AND METHODS

POUNDS (preventing overweight using novel dietary strategies) LOST was a 2-year trial of overweight and obese adults randomly allocated to one of four weight loss diets with targeted percentages of energy derived from fat, protein, and carbohydrates (20, 15, 65%; 20, 25, 55%; 40, 15, 45%; 40, 25, 35%, respectively). hsCRP was measured at baseline, 6, and 24 months among 710 participants, and adiposity as measured by dual X-ray absorptiometry (N = 340) or abdominal computed tomography (N = 126) was correlated with hsCRP change.

RESULTS

At 6 months, hsCRP was reduced in all trial participants by -24.7% (Interquartile range (IQR) +7%, -50%), weight by -6.7% (IQR -3%, -11%), and waist circumference by -6.0% (IQR -3%, -10%) (all P < 0.002), with no significant differences according to dietary composition. The percent change in hsCRP at 6 and 24 months correlated modestly with change in weight, waist circumference, fasting insulin, fasting glucose, HOMA, and most lipid levels. Reductions in hsCRP persisted despite ∼ 50% regain of weight by 24 months. The percent change in hsCRP at 24 months significantly correlated with changes in total body fat (r = 0.42), total abdominal adiposity (r = 0.52), subcutaneous abdominal adiposity (r = 0.52), visceral adiposity (r = 0.47), and hepatic tissue density (r = -0.34) (all P < 0.0006).

CONCLUSION

Weight loss decreased hsCRP by similar magnitude, irrespective of dietary composition. Clinicians concerned about inflammation and cardiovascular risk should recommend weight loss diets most likely to succeed for their patients.

Diabetes risk perception in women with recent gestational diabetes: delivery to the postpartum visit

OBJECTIVE

Low perceived risk for type 2 diabetes (T2DM) may be a barrier to lifestyle change in women with recent gestational diabetes (GDM). We assessed perceived risk for T2DM at delivery and postpartum.

METHODS

We used a validated diabetes risk perception instrument to survey women with GDM at delivery and postpartum. We compared women with low perceived risk for T2DM at delivery to those with high perceived risk.

RESULTS

The majority (N = 43 of 70, 61%) perceived high risk at delivery. Women who perceived low risk were younger (30.7 ± 6.3 versus 35.0 ± 4.5 years, p = 0.003) than women who perceived high risk. Although knowledge of risk factors for T2DM was poor (mean 6.0 ± 1.9, of 11 points), 95% correctly identified GDM as a risk factor. Perceived risk was maintained in most (N = 51 of 58, 88%) who returned for their postpartum visit. Low perceived risk was not associated with loss to follow up, however correct identification of GDM as a risk factor was protective (OR 0.05, 95% CI 0.005, 0.56).

CONCLUSIONS

Risk perception is accurate in most women with GDM at delivery and postpartum. Further study is needed to translate perceived risk into preventive behaviors in women with recent GDM.

Successful weight loss among obese U.S. adults

BACKGROUND

Little is known about weight control strategies associated with successful weight loss among obese U.S. adults in the general population.

PURPOSE

To identify strategies associated with losing at least 5% and 10% of body weight.

METHODS

Multivariable analysis of data from obese adult (BMI ≥30) participants in the 2001-2006 NHANES to identify strategies associated with losing ≥5% and ≥10% of body weight (conducted in 2009-2011).

RESULTS

Of 4021 obese adults, 2523 (63%) reported trying to lose weight in the previous year. Among those attempting weight loss, 1026 (40%) lost ≥5% and 510 (20%) lost ≥10% weight. After adjustment for potential confounders, strategies associated with losing ≥5% weight included eating less fat (OR=1.41, 95% CI=1.14, 1.75); exercising more (OR=1.29, 95% CI=1.05, 1.60); and using prescription weight loss medications (OR=1.77, 95% CI=1.00, 3.13). Eating less fat (OR=1.37, 95% CI=1.04, 1.79); exercising more (OR=1.36, 95% CI=1.12, 1.65); and using prescription weight loss medications (OR=2.05, 95% CI=1.09, 3.86) were also associated with losing ≥10% weight, as was joining commercial weight loss programs (OR=1.72, 95% CI=1.00, 2.96). Adults eating diet products were less likely to achieve 10% weight loss (OR=0.48, 95% CI=0.31, 0.72). Liquid diets, nonprescription diet pills, and popular diets had no association with successful weight loss.

CONCLUSIONS

A substantial proportion of obese U.S. adults who attempted to lose weight reported weight loss, at least in the short term. Obese adults were more likely to report achieving meaningful weight loss if they ate less fat, exercised more, used prescription weight loss medications, or participated in commercial weight loss programs.

Guideline for the management of heart failure caused by systolic dysfunction: part II. Treatment

Several large clinical trials conducted over the past decade have shown that pharmacologic interventions can dramatically reduce the morbidity and mortality associated with heart failure. These trials have modified and enhanced the therapeutic paradigm for heart failure and extended treatment goals beyond limiting congestive symptoms of volume overload. Part II of this two-part article presents treatment recommendations for patients with left ventricular systolic dysfunction. The authors recommend that, if tolerated and not contraindicated, the following agents be used in patients with left ventricular systolic dysfunction: an angiotensin-converting enzyme inhibitor in all patients; a beta blocker in all patients except those who have symptoms at rest; and spironolactone in patients who have symptoms at rest or who have had such symptoms within the past six months. Diuretics and digoxin should be reserved, as needed, for symptomatic management of heart failure. Other treatments or treatment programs may be necessary in individual patients.

Guideline for the management of heart failure caused by systolic dysfunction: Part I. Guideline development, etiology and diagnosis

Over the past decade, the conceptual understanding of heart failure has changed significantly. Several large clinical trials have demonstrated that pharmacologic interventions can dramatically reduce the morbidity and mortality associated with heart failure. These trials have extended the therapeutic paradigm for treating heart failure beyond the goal of limiting congestive symptoms of volume overload. This two-part article presents an evidence-based guideline to assist primary care physicians in evaluating and treating patients with heart failure. Part I describes the new paradigm of heart failure and offers guidance for diagnostic testing. Part II presents a treatment guideline.

Prognostic importance of marital quality for survival of congestive heart failure

Mounting evidence indicates that social support is associated with better outcomes of cardiovascular disease and reduced all-cause mortality. Much less is known about the specific contribution of marital functioning to these outcomes, and the potential prognostic significance of marital quality for congestive heart failure (CHF) has not been explored. Interview and observational measures of marital quality obtained from 189 patients with CHF (139 men and 50 women) and their spouses were examined as predictors of patient survival up to 48 months after assessment and compared with prediction based on illness severity (New York Heart Association [NYHA] class). Four-year survival rates were 52.5% and 68% for male patients and female patients, respectively. In Cox regression analyses, a composite measure of marital quality predicted 4-year survival as well as the patient's concurrent NYHA class did (both p <0.001). Adjusting for CHF severity did not diminish the prognostic significance of marital functioning, and prediction of survival from marital quality appeared stronger for female than for male patients. Thus, when marital quality and NYHA class are considered jointly, they both make independent, statistically significant contributions to the prediction of patient mortality.

Early spontaneous recovery of left ventricular function in patients with myocarditis

The natural history of myocarditis is varied. We describe 6 out of a cohort of 15 consecutive patients with histopathologic evidence of myocarditis who showed a remarkable early symptomatic and spontaneous recovery of left ventricular systolic function. The left ventricular ejection fraction increased to > or = 50% at discharge, and this improvement was maintained at late follow-up. The other 9 patients, despite clinical improvement, were not thought to have spontaneous recovery. Neither clinical severity of the illness (NYHA functional class) nor left ventricular ejection fraction at presentation demonstrated any difference in the two groups. By contrast, a smaller left ventricular internal diameter at end-diastole and a smaller left atrial dimension as determined by transthoracic echocardiography were predictive of spontaneous recovery. Firstly, we confirm that the natural history of myocarditis is indeed varied with the possibility of early spontaneous recovery; secondly we suggest that left ventricular internal diameter at end-diastole and left atrial dimension may have prognostic implications in this disease.

Acute endothelin A receptor blockade causes selective pulmonary vasodilation in patients with chronic heart failure

BACKGROUND

Elevated plasma endothelin-1 (ET-1) levels in patients with chronic heart failure correlate with pulmonary artery pressures and pulmonary vascular resistance. ET(A) receptors on vascular smooth muscle cells mediate pulmonary vascular contraction and hypertrophy. We determined the acute hemodynamic effects of sitaxsentan, a selective ET(A) receptor antagonist, in patients with chronic stable heart failure receiving conventional therapy.

METHODS AND RESULTS

This multicenter, double-blind, placebo-controlled trial enrolled 48 patients with chronic New York Heart Association functional class III or IV heart failure (mean left ventricular ejection fraction 21+/-1%) treated with ACE inhibitors and diuretics. Patients with a baseline pulmonary capillary wedge pressure >/=15 mm Hg and a cardiac index </=2.5 L. min(-1). m(-2) were randomized to 1 of 3 doses (1.5, 3.0, or 6.0 mg/kg) of sitaxsentan or placebo as an intravenous infusion over 15 minutes. Hemodynamic responses were assessed by catheterization of the right side of the heart for 6 hours. Sitaxsentan decreased pulmonary artery systolic pressure, pulmonary vascular resistance, mean pulmonary artery pressure, and right atrial pressure (P</=0.001, 0.003, 0.017, and 0.031, respectively) but had no effect on heart rate, mean arterial pressure, pulmonary capillary wedge pressure, cardiac index, or systemic vascular resistance. Plasma ET-1 levels were elevated at baseline and decreased with sitaxsentan.

CONCLUSIONS

In patients with moderate to severe heart failure receiving conventional therapy, acute ET(A) receptor blockade caused selective pulmonary vasodilation associated with a reduction in plasma ET-1. Sitaxsentan may be of value in the treatment of patients with pulmonary hypertension secondary to chronic heart failure.

What does ATLAS really tell us about "high" dose angiotensin-converting enzyme inhibition in heart failure?

The Assessment of Treatment with Lisinopril and Survival (ATLAS) results have been widely quoted by proponents advocating the use of "high" doses of angiotensin-converting enzyme (ACE) inhibitors for the treatment of heart failure. In ATLAS, however, the relative benefits of "high" versus "low" dose ACE inhibition were small. Intermediate doses of ACE inhibitors proven effective in previous placebo-controlled trials provide benefit that appears likely to equal or exceed the benefit from "high" dose ACE inhibition. Therefore, we recommend that physicians continue to prescribe ACE inhibitors for patients with heart failure based on the target doses used in the placebo-controlled trials and not on the "high" dose target used in ATLAS.

Transpulmonary passage of Albunex as a marker of intracardiac hemodynamics and outcome in chronic congestive heart failure

BACKGROUND

Aggressive management to reduce pulmonary artery systolic pressure (PASP) and pulmonary capillary wedge pressure (PCWP) reduces hospitalization rates and is crucial for patients awaiting transplantation but may require periodic invasive monitoring with right heart catheterization.

METHODS

The purpose of this study was to define the relation of transpulmonary passage of Albunex (Mallinckrodt Medical, St Louis, Mo) to intracardiac hemodynamics and clinical outcome in patients with chronic congestive heart failure (CHF). Patients (n = 38) with chronic CHF underwent graded dobutamine infusion (baseline, 5, 10, 20 microg/kg per minute; 5-minute stages) with 5.0 mL Albunex injected intravenously at each stage. The dobutamine dose at which Albunex appeared in the left ventricle was determined. All patients had right heart catheterization to determine PASP and PCWP.

RESULTS

Transpulmonary passage of Albunex at baseline or at 5 microg/kg per minute dobutamine infusion predicted PCWP <20 mm Hg with a positive predictive value of 100% and a negative predictive value of 79%. Initial appearance of Albunex in the left ventricle at a dobutamine dose of 20 microg/kg per minute or failure to appear at any dose predicted a PCWP >20 mm Hg with a positive predictive value of 100% and a negative predictive value of 94%. No patient with Albunex passage at baseline sustained a major adverse event. Major adverse events occurred in 11 of 21 patients in whom Albunex either failed to cross or crossed the pulmonary bed at a dose of 20 microg/kg per minute of dobutamine.

CONCLUSION

In patients with chronic CHF, transpulmonary passage of Albunex during dobutamine infusion can be used to predict both elevated and normal intracardiac pressures and to identify a subset of patients at high risk for an adverse outcome.

New graphical method for evaluating gas exchange in congestive heart failure

PURPOSE

The purpose of this study was to determine the usefulness of a new graphical method for evaluating gas exchange (GE), as applied to three common averaging techniques used during rest, exercise, and recovery in patients with congestive heart failure (CHF).

METHODS

Fifty patients' resting, exercise, and recovery GE graphs were evaluated using a new graphical method to determine oxygen consumption (VO2), ventilation (VE), and respiratory exchange ratio (RER). Precision of the new method was evaluated by repeated measures using the same investigator, an additional investigator, and an untrained student. A 1-min rolling time average (RTA) updated every 20 s was used as the reference to the graphical method and the metabolic cart's computer analysis. Breath-by-breath data were evaluated using three averaging techniques, average 5 of 7 breaths (5/7), average of 8 breaths (AVG 8), and 30-s average (30-s). Differences between the computer and the graphical method were assessed by two-sided t-tests; ANOVA was used between the three investigators and also between the three averaging techniques.

RESULTS

There were no significant differences of repeated measures between trained and untrained investigators. The graphical method results were significantly different than the computer results. The only difference with RTA involved computer resting values, which were also different than the graphical method.

CONCLUSION

In conclusion, the graphical method may be used to standardize GE evaluation because it displays excellent intrainvestigator precision and good interinvestigator precision between experienced and inexperienced investigators. Averaging techniques less than 30 s have greater bias when using computer-derived values, although when incorporating the graphical method the averaging technique chosen has little influence on all measures.

Diurnal variation in plasma norepinephrine in patients with heart failure

Diurnal variation in plasma norepinephrine (PNE) levels is well documented in healthy individuals but not in patients with heart failure. Therefore, we attempted to determine variations in PNE levels over 24 hours, measured hourly, in six patients with an ejection fraction below 40% and a history of heart failure of longer than 3 months. Three controls without a history of heart failure also were evaluated. Both patients and controls had diurnal variations in PNE, with highest levels occurring during the day and lowest at night. When data in patients were evaluated by 6-hour time intervals the mean value for 6:00 A.M.-12:00 noon was approximately twice as high as 12:00 midnight-6:00 A.M. (689+/-329 vs 338+/-166 pg/ml, p<0.05, respectively). Patients also had significant peak to trough variation in PNE levels compared with controls (959+/-396 vs 386+/-84 pg/ml, p<0.02, respectively). These results suggest that significant intrapatient variations in PNE occur over 24 hours in patients with heart failure. These variations may have to be accounted for when evaluating and treating patients with heart failure.

Pharmacokinetics of torsemide in patients with decompensated and compensated congestive heart failure

Plasma pharmacokinetics of oral furosemide have been shown to be influenced by degree of decompensation in patients with congestive heart failure (CHF). This open-label, sequential comparison trial was conducted to determine whether CHF decompensation also alters the pharmacokinetics and pharmacodynamics of torsemide. Twelve patients with CHF, defined by either hemodynamic parameters or clinical signs and symptoms, were enrolled. On admission for treatment of their CHF, the patients were given 100 mg oral torsemide (phase A). A second dose of oral torsemide 100 mg was administered after hemodynamic parameters and clinical signs and symptoms of decompensated CHF resolved (phase B). Plasma and urine samples were collected over a 24-hour period for determination of torsemide concentrations and urine sodium. Hemodynamic measurements and physical signs and symptoms also were evaluated. During phase A, patients had significantly greater urine output and fractional sodium excretion compared with phase B. A significant increase in the area under the plasma concentration-time curve (AUC) was observed during phase B compared with phase A. However, no significant differences in maximal excretion rate of torsemide were noted between phase A and phase B. Heart failure status slightly affects the plasma pharmacokinetics of torsemide; however, this does not significantly alter the maximal urinary excretion rate of torsemide.

Heart failure: clinical implications of recent trials

The frustration has been in identifying drugs that have a positive impact on cardiac performance and a negative effect on mortality. ACE inhibitors, often with diuretics and possibly with digoxin, continue to show impressive outcomes in major studies.

Relation of neurohumoral activation to clinical variables and degree of ventricular dysfunction: a report from the Registry of Studies of Left Ventricular Dysfunction. SOLVD Investigators

OBJECTIVES

This study examined the relation between neurohumoral activation and severity of left ventricular dysfunction and congestive heart failure in a broad group of patients with depressed left ventricular function who were not recruited on the basis of eligibility for a therapeutic trial.

BACKGROUND

Previous studies have established the presence of neurohumoral activation in patients with severe congestive heart failure. It is not known whether the activation of these neurohumoral mechanisms is related to an impairment in left ventricular function.

METHODS

From the 6,273 patients recruited into the Studies of Left Ventricular Dysfunction Registry (SOLVD), a subgroup of 859 patients were randomly selected, and their plasma norepinephrine, plasma renin activity, arginine vasopressin and atrial natriuretic peptide levels were correlated with clinical findings, New York Heart Association functional class, left ventricular ejection fraction and drug use.

RESULTS

There was a weak but significant correlation between ejection fraction and an increase in plasma norepinephrine (rho = -0.18, p < 0.0001), plasma renin activity (rho = -0.24, p < 0.0001) and arginine vasopressin (rho = -0.12, p < 0.003). The only exception was atrial natriuretic peptide, which showed the best correlation to ejection fraction (rho = -0.37, p < 0.0001). Deterioration in functional class was associated more with increases in atrial natriuretic peptide (p = 0.0003) and plasma renin activity (p = 0.0003) and less with an increase in plasma norepinephrine. Of the clinical variables, elevated jugular venous pressure and third heart sound (S3) gallop were significantly associated with increased levels of plasma norepinephrine, plasma renin activity and atrial natriuretic peptide. We then compared the relation of neurohormones with clinical signs, functional status, ejection fraction and drug therapy and controlled for mutual interactive effects. After adjustment, a decrease in ejection fraction was still significantly related to an increase in plasma norepinephrine, plasma renin activity and atrial natriuretic peptide. In contrast, only a difference between functional classes I and III/IV was associated with an increase in plasma renin activity and atrial natriuretic peptide levels.

CONCLUSIONS

Neurohumoral activation in patients with heart failure is related to severity of left ventricular functional depression, and this relation is independent of functional class or concomitant drug therapy.

Prospective, double-blind, placebo-controlled trial of low-dose amiodarone in patients with severe heart failure and asymptomatic frequent ventricular ectopy

Sudden cardiac death is a common cause of mortality in patients with congestive heart failure. To determine if low-dose amiodarone could reduce sudden death among these patients, a prospective, placebo-controlled, double-blind pilot trial was conducted. One hundred one patients with ejection fractions less than 30%, New York Heart Association class III or IV symptoms, and frequent but asymptomatic spontaneous ventricular ectopy (Lown class II to V) were randomly assigned to treatment with low-dose amiodarone (400 mg/day for 4 weeks and then 200 mg/day) or placebo. Mean follow-up was 357 days (range 4 to 1009 days). Side effects were infrequent and there was no difference in the incidence of side effects between the treatment groups. The frequency of spontaneous ventricular ectopy in the group receiving amiodarone fell from 4992 +/- 1240 beats/24 hours at baseline to 1135 +/- 494 beats/24 hours after 1 month of treatment (p = 0.02) and remained low after 6 months, while there was no change in ventricular ectopy among the patients receiving placebo. Despite the reduction in ectopy, there was no improvement in mortality or decrease in the incidence of sudden death. One-year mortality by Kaplan-Meier analysis was 28% in the group receiving amiodarone and 19% in the group receiving placebo (p = NS). One-year mortality in patients with greater than 75% reduction in ventricular ectopy after 1 month of treatment was 31% versus 17% in patients with less than or equal to 75% ectopic suppression (p = NS).(ABSTRACT TRUNCATED AT 250 WORDS)

Treatment of cardiogenic shock with the Hemopump left ventricular assist device

A multiinstitutional study is in progress to evaluate the Hemopump in the treatment of cardiogenic shock. Fifty-three patients with refractory cardiogenic shock were selected for Hemopump assistance. The hemodynamic definition of cardiogenic shock included (1) a cardiac index of less than 2.0 L.min-1.m-2, (2) pulmonary capillary wedge pressure of greater than 18 mm Hg, and (3) a systolic blood pressure of less than 90 mm Hg or a left ventricular work index of less than 1,500 g-m.m-2.min-1. The Hemopump was successfully inserted in 41 of 53 patients (77.3%). A significant improvement in the hemodynamic status was seen during Hemopump assistance. A minimal level of hemolysis was observed. No leg ischemia was observed. The 30-day overall survival of the Hemopump group was 31.7%. Criteria establishing indications for use and clinical utility are proposed. We conclude that the Hemopump provides significant hemodynamic support of the patient in cardiogenic shock allowing for recovery from ventricular stunning in marginal ventricles, and that in select patients the Hemopump may offer a major improvement in survival over conventional therapy.

Computer analysis of physiologic signals in a cardiovascular research laboratory

A comprehensive computer program which provides immediate computation and feedback has been developed for data acquisition and analysis of signals in a cardiovascular animal laboratory. The system is based on a microcomputer equipped with analog-to-digital converter and supports function modules which digitize, filter, and differentiate up to 8 simultaneously sampled cardiovascular signals. The program detects, analyses, and plots incoming and averaged beats. Beat-by-beat signal averaging for each channel is performed and cardiac cycles are partitioned automatically. For each cardiac and average cycle the amplitude at 6 physiologic fiducial markers are measured and derived calculations are made. Channel vs channel plots and loop area measurements are also computed and displayed. The computer algorithms have been shown to give accurate, precise, and reproducible results when tested on canine cardiovascular data. Also, it has been demonstrated that signal averaging is an appropriate analysis technique for cardiovascular signals.

The oxygen consumption paradox of "stunned myocardium" in dogs

The contractile state of the heart is a major determinant of myocardial oxygen consumption. Since regional myocardial contractility can be severely impaired following a transient coronary occlusion, post-ischemic myocardium is frequently assumed to consume less oxygen. To test this assumption, regional myocardial function and oxygen consumption were studied in anesthetized dogs during 2 h of myocardial reperfusion following either a 15-min (Group I) or 4-h (Group II) left anterior descending coronary artery occlusion. Both groups developed similar post-ischemic regional dysfunction characterized by paradoxical motion (negative shortening). Measured as a percent of baseline segment shortening, anterior wall function in Group I (n = 8) and Group II (n = 5) at 30 min of reperfusion was -33 +/- 11% and -34 +/- 16% (p = NS) and at 120 min was -23 +/- 9% and -40 +/- 16% (p = NS). However, the two groups showed a marked difference in regional myocardial oxygen consumption during reperfusion. Despite the abnormal wall motion, regional oxygen consumption in Group I at 30 and 120 min of reperfusion was unchanged from pre-ischemic levels as measured as a percent of baseline: 104 +/- 20% (p = NS) and 111 +/- 21% (p = NS). In contrast, regional oxygen consumption in Group II was markedly depressed from baseline at 30 and 120 min of reperfusion: 42 +/- 7% (p less than .01) and 40 +/- 8% (p less than .01). To determine whether the dissociation between regional myocardial oxygen consumption and function in Group I was related to mitochondrial uncoupling, six additional dogs were studied. Tissue samples were obtained from post-ischemic myocardium after 120 min of reperfusion following a 15-min coronary artery occlusion, and compared to non-ischemic myocardium. There were no differences in the in vitro mitochondrial respiratory rates or oxidative phosphorylation capacity between the post-ischemic and non-ischemic myocardium. Therefore, in the post-ischemic myocardium, significant depressions in regional contractility may not be associated with falls in oxygen consumption. Following a 15-min coronary artery occlusion, the injured myocardium maintains a paradoxically high oxygen consumption with normal mitochondrial function despite decreased contractility and abnormal wall motion.