Can sodium and potassium measured in timed voids be used as reference instruments for validating self-report instruments? Results from a urine calibration study

BACKGROUND

Sodium and potassium measured in 24-h urine collections are often used as reference measurements to validate self-reported dietary intake instruments.

OBJECTIVES

To evaluate whether collection and analysis of a limited number of urine voids at specified times during the day ("timed voids") can provide alternative reference measurements, and to identify their optimal number and timing.

METHODS

We used data from a urine calibration study among 441 adults aged 18-39 y. Participants collected each urine void in a separate container for 24 h and recorded the collection time. For the same day, they reported dietary intake using a 24-h recall. Urinary sodium and potassium were analyzed in a 24-h composite sample and in 4 timed voids (morning, afternoon, evening, and overnight). Linear regression models were used to develop equations predicting log-transformed 24-h urinary sodium or potassium levels using each of the 4 single timed voids, 6 pairs, and 4 triples. The equations also included age, sex, race, BMI (kg/m2), and log creatinine. Optimal combinations minimizing the mean squared prediction error were selected, and the observed and predicted 24-h levels were then used as reference measures to estimate the group bias and attenuation factors of the 24-h dietary recall. These estimates were compared.

RESULTS

Optimal combinations found were as follows: single voids-evening; paired voids-afternoon + overnight (sodium) and morning + evening (potassium); and triple voids-morning + evening + overnight (sodium) and morning + afternoon + evening (potassium). Predicted 24-h urinary levels estimated 24-h recall group biases and attenuation factors without apparent bias, but with less precision than observed 24-h urinary levels. To recover lost precision, it was estimated that sample sizes need to be increased by ∼2.6-2.7 times for a single void, 1.7-2.1 times for paired voids, and 1.5-1.6 times for triple voids.

CONCLUSIONS

Our results provide the basis for further development of new reference biomarkers based on timed voids.

CLINICAL TRIAL REGISTRY

clinicaltrials.gov as NCT01631240.

Glucagon-Like Peptide-1 Receptor Agonists and Pancreatic Cancer Risk in Patients With Type 2 Diabetes

Importance

Concerns have been raised that glucagon-like peptide-1 receptor agonists (GLP-1RA) may increase the risk of pancreatic cancer.

Objective

To investigate the association of GLP-1RA treatment with pancreatic cancer incidence over 9 years of follow-up.

Design, Setting, and Participants

In this population-based historical cohort study, adult patients (aged 21 to 89 years) with type 2 diabetes insured by Clalit Healthcare Services, the largest state-mandated health organization in Israel, were followed up from 2009, when GLP-1RA became available in Israel, until pancreatic cancer diagnosis, death, reaching age 90 years, or end of follow-up (December 2017). Data were analyzed from June 2022 to November 2023.

Exposures

Treatment with GLP-1RA was compared with basal insulin.

Main Outcome and Measures

Pancreatic cancer incidence was compared according to weighted cumulative exposures to GLP-1RA and to basal insulin in a Cox model implemented in discrete time, with time origin at 2 years after diabetes diagnosis, adjusting for confounding. In sensitivity analyses, propensity score-matched pair new-user design and prevalent new-user design were used for the comparison. Because of risk for reverse-causation bias, results in the fifth to seventh year after medication were emphasized.

Results

During a cumulative follow-up of 3 290 439 person-years of 543 595 adults with a mean (SD) age of 59.9 (12.8) years (277 502 women [51%]) with incident diabetes, 1665 patients received pancreatic cancer diagnoses. In total, 33 377 patients (6.1%) used GLP-1RA and 106 849 (19.7%) used basal insulin. The estimated hazard ratio (HR) for pancreatic cancer associated with incremental use of 1 defined daily dose per day of GLP-1RA compared with basal insulin in the fifth to seventh year previously (all other characteristics, including age, sex, ethnic background, sociodemographic status, baseline body mass index, smoking history, history of pancreatitis, other glucose-lowering medications treatment history, and length of diabetes, being equal) was 0.50 (95% CI, 0.15-1.71). The new-user and prevalent new-user designs showed HRs from the fifth year onwards following initiation of GLP-1RA vs basal insulin of 0.52 (95 % CI, 0.19-1.41) and 0.75 (95 % CI, 0.37-1.53), respectively.

Conclusions and Relevance

In this historical cohort study of adults with type 2 diabetes, no support for an increased pancreatic cancer incidence over 7 years following start of GLP-1RA treatment was found. However, monitoring for pancreatic cancer risk beyond 7 years following initiation of therapy is still required.

Trial Registration

ClinicalTrials.gov Identifier: NCT02072902.

Reverse causation biases weighted cumulative exposure model estimates, but can be investigated in sensitivity analyses

OBJECTIVES

To examine the effects of reverse causation on estimates from the weighted cumulative exposure (WCE) model that is used in pharmacoepidemiology to explore drug-health outcome associations, and to identify sensitivity analyses for revealing such effects.

STUDY DESIGN AND SETTING

314,099 patients with diabetes under Clalit Health Services, Israel, were followed over 2002-2012. The association between metformin and pancreatic cancer (PC) was explored using a WCE model within the framework of discrete-time Cox regression. We used computer simulations to explore the effects of reverse causation on estimates of a WCE model and to examine sensitivity analyses for revealing and adjusting for reverse causation. We then applied those sensitivity analyses to our data.

RESULTS

Simulation demonstrated bias in the weighted cumulative exposure model and showed that sensitivity analysis could reveal and adjust for these biases. In our data, a positive association was observed (hazard ratio (HR) = 3.24, 95% confidence interval (CI): 2.24-4.73) with metformin exposure in the previous 2 years. After applying sensitivity analysis, assuming reverse causation operated up to 4 years before cancer diagnosis, the association between metformin and PC was no longer apparent.

CONCLUSION

Reverse causation can cause substantial bias in the WCE model. When suspected, sensitivity analyses based on causal analysis are advocated.

Longitudinal bidirectional link between socioeconomic position and health: a national panel survey analysis

BACKGROUND

Health inequities can stem from socioeconomic position (SEP) leading to poor health (social causation) or poor health resulting in lower SEP (health selection). We aimed to examine the longitudinal bidirectional SEP-health associations and identify inequity risk factors.

METHODS

Longitudinal Household Israeli Panel survey participants (waves 1-4), age ≥25 years, were included (N=11 461; median follow-up=3 years). Health rated on a 4-point scale was dichotomised as excellent/good and fair/poor. Predictors included SEP parameters (education, income, employment), immigration, language proficiency and population group. Mixed models accounting for survey method and household ties were used.

RESULTS

Examining social causation, male sex (adjusted OR 1.4; 95% CI 1.1 to 1.8), being unmarried, Arab minority (OR 2.4; 95% CI 1.6 to 3.7, vs Jewish), immigration (OR 2.5; 95% CI 1.5 to 4.2, reference=native) and less than complete language proficiency (OR 2.22; 95% CI 1.50 to 3.28) were associated with fair/poor health. Higher education and income were protective, with 60% lower odds of subsequently reporting fair/poor health and 50% lower disability likelihood. Accounting for baseline health, higher education and income were associated with lower likelihood of health deterioration, while Arab minority, immigration and limited language proficiency were associated with higher likelihood. Regarding health selection, longitudinal income was lower among participants reporting poor baseline health (85%; 95% CI 73% to 100%, reference=excellent), disability (94%; 95% CI 88% to 100%), limited language proficiency (86%; 95% CI 81% to 91%, reference=full/excellent), being single (91%; 95% CI 87% to 95%, reference=married), or Arab (88%; 95% CI 83% to 92%, reference=Jews/other).

CONCLUSION

Policy aimed at reducing health inequity should address both social causation (language, cultural, economic and social barriers to good health) and health selection (protecting income during illness and disability).

Urinary Sucrose and Fructose From Spot Urine May Be Used as a Predictive Biomarker of Total Sugar Intake-Findings From a Controlled Feeding Study

BACKGROUND

Recently, we confirmed 24-h urinary sucrose plus fructose (24 uSF) as a predictive biomarker of total sugar intake. However, the collection of 24-h urine samples has limited feasibility in population studies.

OBJECTIVE

We investigated the utility of the urinary sucrose plus fructose (uSF) biomarker measured in spot urine as a measure of 24 uSF biomarker and total sugar intake.

METHODS

Hundred participants, 18-70 y of age, from the Phoenix Metropolitan Area completed a 15-d feeding study. For 2 of the 8 collected 24-h urine samples, each spot urine sample was collected in a separate container. We considered 4 timed voids of the day [morning (AM) void: first void 08:30-12:30; afternoon (PM) void: first void 12:31-17:30; evening (EVE) void: first void 17:31-12:00; and next-day (ND) void: first void 04:00-12:00]. We investigated the performance of uSF from 1 void, and uSF combined from 2 and 3 voids as a measure of 24 uSF and sugar intake.

RESULTS

The biomarker averaged from PM/EVE void strongly correlated with 24 uSF (partial r = 0.75). The 24 uSF predicted from the PM/EVE combination was significantly associated with observed sugar intake and was selected for building the calibrated biomarker equation (marginal R2 = 0.36). Spot urine-based calibrated biomarker, ie, biomarker-estimated sugar intake was moderately correlated with the 15-d mean-observed sugar intake (r = 0.50).

CONCLUSIONS

uSF measured from a PM and EVE void may be used to generate biomarker-based sugar intake estimate when collecting 24-h urine samples is not feasible, pending external validation.

Celiac plexus radiosurgery for pain management in advanced cancer: An international phase II trial, health-related quality of life (HRQOL) outcomes

662

Background: Upper abdominal / lower back pain characterizes celiac plexus involvement from pancreatic and other cancers which may impair HRQOL; its satisfactory treatment is an unmet clinical need. We hypothesized that ablative radiation delivered to the celiac plexus would decrease pain and improve HRQOL. Methods: An international single arm Phase II study included patients with an average pain level ≥ 5/11 on the brief pain inventory (BPI), ECOG 0-2, and anatomical involvement of the celiac axis. The intervention was a single fraction of 25Gy delivered to the celiac plexus. The primary endpoint was ‘complete or partial (≥2 points) pain response’ based upon the BPI ‘average pain’ 11-point scale. Changes in Health-related QOL at 3 & 6 weeks compared to baseline were secondary endpoints as measured by FACT-Hep, > 8 point change being the minimal clinically important difference (MCID). Evaluable patients included eligible irradiated subjects, who had stable pain levels pre-treatment, and were alive 3 weeks’ post-treatment. The sample size was 90 evaluable patients, giving 90% power to show response rate ≥ 40%. Opioid usage was assessed using intravenous morphine equivalent dose. Sensitivity HRQOL analyses imputed worsened outcomes (-9 for total FACT-Hep) for missing data. Results: Between 2018 and 2022, 149 patients were enrolled, 90/125 who received treatment were evaluable. Median age was 65.5 years (range 28-88), 65% were female, 92% had pancreatic cancer, and 86% had metastatic disease. Median Zubrod PS was 1, median number of systemic treatment lines was 1 (range 0-5), and median baseline opioid use 31 mg/d. At 3 weeks, 48 (53.3%, 95% CI 42.5-63.9) had at least a partial pain, the BPI ‘average pain’ score decreased by a mean of 2.5 points at 3 weeks (86/90 reported) and 3.2 points at 6 weeks (67/90 reported), both p < 0.001. Opioid usage decreased by 0.6 mg/d at 3 weeks (NS) and 16.9 mg/d at 6 weeks (p = 0.005). The FACT-Hep total score increased by 7.8 points at 3 weeks (54/90 reported, NS diff. from 8) and 16.6 points at 6 weeks (45/90 reported, sig. > 8, p = 0.01), showing an improvement in patients’ HRQOL. Changes in FACT-Hep were especially noted in the Physical Well Being subscale. The Trial Outcome Index (sum of physical, functional & disease-specific concerns) increased markedly at 3 weeks (6.6 points, p = 0.005) after treatment and even more after 6 weeks (14.5 points, p < 0.). Sensitivity analyses demonstrated improvements in HRQOL at 3 and 6 weeks (1.1, 3.8), but these were less than MCID. Conclusions: Celiac plexus SBRT decreases pain and opioid use amongst patients with pancreatic cancer and other tumors invading the celiac axis. The treatment appears to improve HRQOL. Supported by Gateway for Cancer Research and the Israel Cancer Association. Clinical trial information: NCT03323489 .

Immunogenicity and efficacy of fourth BNT162b2 and mRNA1273 COVID-19 vaccine doses; three months follow-up

Booster doses for the ongoing COVID-19 pandemic are under consideration in many countries. We report a three-month follow-up of 700 participants in a fourth vaccine dose study, comparing BNT162b2 and mRNA1273, administered four months after a third BNT162b2 dose. The primary outcomes are the levels of IgG, neutralizing antibodies, and microneutralization and the secondary outcomes are the levels of IgA and T cell activation, and clinical outcomes of SARS-CoV-2 infection and substantial symptomatic disease. Waning of the immune response is evident during follow-up, with an 11% (β = 0.89, 95% CI, 0.88-0.9) and 21% (β = 0.79, 95% CI, 0.76-0.82) multiplicative decay per week of IgG and neutralizing antibodies, respectively, in the mRNA1273 group, and of 14% (β = 0.86, 95% CI, 0.86-0.87) and 26% (β = 0.74, 95% CI, 0.72-0.76), respectively, in the BNT162b2 group. Direct neutralization of Omicron variants is low relative to ancestral strains. Cumulatively over the study period, both vaccines show little efficacy against infection but were highly efficacious against substantial symptomatic disease [89% [(IRR 0.11, 95% CI, 0.02-0.37) and 71% (IRR 0.29, 95% CI, 0.13-0.57) for mRNA1273 and BNT162b2, respectively]. These results are informative for further boosting policy-making. Trial registration numbers (clinicaltrials.gov): NCT05231005 and NCT05230953.

The Association Between Pre-Booster Vaccination Antibody Levels and the Risk of SARS-CoV-2 Infection

The correlation between Anti-SARS-CoV-2 antibody levels and infection was reported. Here, we estimated the role of pre-fourth-dose levels using data from 1,098 health-care-workers. The risk of infection was reduced by 46% (95% CI: 29-59%) with a 10-fold increase in pre-booster levels. Pre-booster antibody levels could be used to optimally time boosters.

Evaluating a Model of Added Sugar Intake Based on Amino Acid Carbon Isotope Ratios in a Controlled Feeding Study of U.S. Adults

Previous studies suggest that amino acid carbon stable isotope ratios (CIRAAs) may serve as biomarkers of added sugar (AS) intake, but this has not been tested in a demographically diverse population. We conducted a 15-day feeding study of U.S. adults, recruited across sex, age, and BMI groups. Participants consumed personalized diets that resembled habitual intake, assessed using two consecutive 7-day food records. We measured serum (n = 99) CIRAAs collected at the end of the feeding period and determined correlations with diet. We used forward selection to model AS intake using participant characteristics and 15 CIRAAs. This model was internally validated using bootstrap optimism correction. Median (25th, 75th percentile) AS intake was 65.2 g/day (44.7, 81.4) and 9.5% (7.2%, 12.4%) of energy. The CIR of alanine had the highest, although modest, correlation with AS intake (r = 0.32, p = 0.001). Serum CIRAAs were more highly correlated with animal food intakes, especially the ratio of animal to total protein. The AS model included sex, body weight and 6 CIRAAs. This model had modest explanatory power (multiple R2 = 0.38), and the optimism-corrected R2 was lower (R2 = 0.15). Further investigations in populations with wider ranges of AS intake are warranted.

Comparing immunogenicity and efficacy of two different mRNA-based COVID-19 vaccines as a fourth dose; six-month follow-up, Israel, 27 December 2021 to 24 July 2022

We assess the immunogenicity and efficacy of Spikevax and Comirnaty as fourth dose COVID-19 vaccines. Six months post-fourth-dose, IgG levels were higher than pre-fourth dose at 1.58-fold (95% CI: 1.27-1.97) in Spikevax and 1.16-fold (95% CI: 0.98-1.37) in Comirnaty vaccinees. Nearly 60% (159/274) of vaccinees contracted SARS-CoV-2. Infection hazard ratios (HRs) for Spikevax (0.82; 95% CI: 0.62-1.09) and Comirnaty (0.86; 95% CI: 0.65-1.13) vaccinees were similar, as were substantial-disease HRs, i.e. 0.28 (95% CI: 0.13-0.62) and 0.51 (95% CI: 0.27-0.96), respectively.

Durability of Immune Response After COVID-19 Booster Vaccination and Association With COVID-19 Omicron Infection

IMPORTANCE

The BNT162b2 two-dose vaccine (BioNTech/Pfizer) has high effectiveness that wanes within several months. The third dose is effective in mounting a significant immune response, but its durability is unknown.

OBJECTIVE

To compare antibody waning after second and third doses and estimate the association of antibody kinetics with susceptibility to infection with the Omicron variant of SARS-CoV-2.

DESIGN, SETTING, AND PARTICIPANTS

In a prospective longitudinal cohort study in a tertiary medical center in Israel, health care workers who received the BNT162b2 vaccine were followed up monthly for IgG and neutralizing antibody levels. Linear mixed models were used to compare antibody titer waning of second and third doses and to assess whether antibody dynamics were associated with Omicron transmission. Avidity, T cell activation, and microneutralization of sera against different variants of concern were assessed for a subgroup.

EXPOSURE

Vaccination with a booster dose of the BNT162b2 vaccine.

MAIN OUTCOMES AND MEASURES

The primary outcome was the rate of antibody titer change over time, and the secondary outcome was SARS-CoV-2 Omicron variant infection, as confirmed by reverse transcriptase-polymerase chain reaction.

RESULTS

Overall, 4868 health care workers (mean [SD] age, 46.9 [13.7] years; 3558 [73.1%] women) and 3972 health care workers (mean [SD] age, 48.5 [14.1] years; 996 [74.9%] women) were followed up for 5 months after their second and third vaccine doses, respectively. Waning of IgG levels was slower after the third compared with the second dose (1.32%/d [95% CI, 1,29%/d to 1.36%/d] vs 2.26% [95% CI, 2.13%/d 2.38%/d]), as was waning of neutralizing antibody levels (1.32%/d [95% CI, 1.21%/d to 1.43%/d] vs 3.34%/d [95% CI, 3.11%/d to 3.58%/d]). Among 2865 health care workers assessed for Omicron incidence during an additional 2 months of follow-up, lower IgG peak (ratio of means 0.86 [95% CI, 0.80-0.91]) was associated with Omicron infection, and among participants aged 65 years and older, faster waning of IgG and neutralizing antibodies (ratio of mean rates, 1.40; [95% CI, 1.13-1.68] and 3.58 [95% CI, 1.92-6.67], respectively) were associated with Omicron infection. No waning in IgG avidity was observed 112 days after the third dose. Live neutralization of Omicron was lower compared with previous strains, with a geometric mean titer at the peak of 111 (95% CI, 75-166), compared with 942 (95% CI, 585-1518) for WT, 410 (95% CI, 266-634) for Delta; it demonstrated similar waning to 26 (95% CI, 16-42) within 4 months. Among 77 participants tested for T cell activity, mean (SD) T cell activity decreased from 98 (5.4) T cells/106 peripheral blood mononuclear cells to 59 (9.3) T cells/106 peripheral blood mononuclear cells.

CONCLUSIONS AND RELEVANCE

This study found that the third vaccine dose was associated with greater durability than the second dose; however, Omicron was associated with greater resistance to neutralization than wild type and Delta variants of concern. Humoral response dynamics were associated with susceptibility to Omicron infection.

Protection and Waning of Natural and Hybrid Immunity to SARS-CoV-2

BACKGROUND

Infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) provides natural immunity against reinfection. Recent studies have shown waning of the immunity provided by the BNT162b2 vaccine. The time course of natural and hybrid immunity is unknown.

METHODS

Using the Israeli Ministry of Health database, we extracted data for August and September 2021, when the B.1.617.2 (delta) variant was predominant, on all persons who had been previously infected with SARS-CoV-2 or who had received coronavirus 2019 vaccine. We used Poisson regression with adjustment for confounding factors to compare the rates of infection as a function of time since the last immunity-conferring event.

RESULTS

The number of cases of SARS-CoV-2 infection per 100,000 person-days at risk (adjusted rate) increased with the time that had elapsed since vaccination with BNT162b2 or since previous infection. Among unvaccinated persons who had recovered from infection, this rate increased from 10.5 among those who had been infected 4 to less than 6 months previously to 30.2 among those who had been infected 1 year or more previously. Among persons who had received a single dose of vaccine after previous infection, the adjusted rate was low (3.7) among those who had been vaccinated less than 2 months previously but increased to 11.6 among those who had been vaccinated at least 6 months previously. Among previously uninfected persons who had received two doses of vaccine, the adjusted rate increased from 21.1 among those who had been vaccinated less than 2 months previously to 88.9 among those who had been vaccinated at least 6 months previously.

CONCLUSIONS

Among persons who had been previously infected with SARS-CoV-2 (regardless of whether they had received any dose of vaccine or whether they had received one dose before or after infection), protection against reinfection decreased as the time increased since the last immunity-conferring event; however, this protection was higher than that conferred after the same time had elapsed since receipt of a second dose of vaccine among previously uninfected persons. A single dose of vaccine after infection reinforced protection against reinfection.

Establishing 24-Hour Urinary Sucrose Plus Fructose as a Predictive Biomarker for Total Sugars Intake

BACKGROUND

Twenty-four-hour urinary sucrose and fructose (24uSF) has been studied as a biomarker of total sugars intake in two feeding studies conducted in the United Kingdom (UK) and Arizona (AZ). We compare the biomarker performance in these populations, testing whether it meets the criteria for a predictive biomarker.

METHODS

The UK and AZ feeding studies included 13 and 98 participants, respectively, aged 18 to 70 years, consuming their usual diet under controlled conditions. Linear mixed models relating 24uSF to total sugars and personal characteristics were developed in each study and compared. The AZ calibrated biomarker equation was applied to generate biomarker-estimated total sugars intake in UK participants. Stability of the model across AZ study subpopulations was also examined.

RESULTS

Model coefficients were similar between the two studies [e.g., log(total sugars): UK 0.99, AZ 1.03, P = 0.67], as was the ratio of calibrated biomarker person-specific bias to between-person variance (UK 0.32, AZ 0.25, P = 0.68). The AZ equation estimated UK log(total sugar intakes) with mean squared prediction error of 0.27, similar to the AZ study estimate (0.28). Within the AZ study, the regression coefficients of log(total sugars) were similar across age, gender, and body mass index subpopulations.

CONCLUSIONS

Similar model coefficients in the two studies and good prediction of UK sugar intakes by the AZ equation suggest that 24uSF meets the criteria for a predictive biomarker. Testing the biomarker performance in other populations is advisable.

IMPACT

Applications of the 24uSF biomarker will enable improved assessment of the role of sugars intake in risk of chronic disease, including cancer. See related commentary by Prentice, p. 1151.

Measurement Error Affecting Web- and Paper-Based Dietary Assessment Instruments: Insights From the Multi-Cohort Eating and Activity Study for Understanding Reporting Error

Few biomarker-based validation studies have examined error in online self-report dietary assessment instruments, and food records (FRs) have been considered less than food frequency questionnaires (FFQs) and 24-hour recalls (24HRs). We investigated measurement error in online and paper-based FFQs, online 24HRs, and paper-based FRs in 3 samples drawn primarily from 3 cohorts, comprising 1,393 women and 1,455 men aged 45-86 years. Data collection occurred from January 2011 to October 2013. Attenuation factors and correlation coefficients between reported and true usual intake for energy, protein, sodium, potassium, and respective densities were estimated using recovery biomarkers. Across studies, average attenuation factors for energy were 0.07, 0.07, and 0.19 for a single FFQ, 24HR, and FR, respectively. Correlation coefficients for energy were 0.24, 0.23, and 0.40, respectively. Excluding energy, the average attenuation factors across nutrients and studies were 0.22 for a single FFQ, 0.22 for a single 24HR, and 0.51 for a single FR. Corresponding correlation coefficients were 0.31, 0.34, and 0.53, respectively. For densities (nutrient expressed relative to energy), the average attenuation factors across studies were 0.37, 0.17, and 0.50, respectively. The findings support prior research suggesting different instruments have unique strengths that should be leveraged in epidemiologic research.

Metformin Treatment Among Men With Diabetes and the Risk of Prostate Cancer: A Population-Based Historical Cohort Study

There is conflicting evidence regarding the association between metformin treatment and prostate cancer risk in diabetic men. We investigated this association in a population-based Israeli cohort of 145,617 men aged 21–89 years with incident diabetes who were followed over the period 2002–2012. We implemented a time-dependent covariate Cox model, using weighted cumulative exposure to relate metformin history to prostate cancer risk, adjusting for use of other glucose-lowering medications, age, ethnicity, and socioeconomic status. To adjust for time-varying glucose control variables, we used inverse probability weighting of a marginal structural model. With 666,553 person-years of follow-up, 1,592 men were diagnosed with prostate cancer. Metformin exposure in the previous year was positively associated with prostate cancer risk (per defined daily dose; without adjustment for glucose control, hazard ratio (HR) = 1.53 (95% confidence interval (CI): 1.19, 1.96); with adjustment, HR = 1.42 (95% CI: 1.04, 1.94)). However, exposure during the previous 2–7 years was negatively associated with risk (without adjustment for glucose control, HR = 0.58 (95% CI: 0.37, 0.93); with adjustment, HR = 0.60 (95% CI: 0.33, 1.09)). These positive and negative associations with previous-year and earlier metformin exposure, respectively, need to be confirmed and better understood.

An evaluation of the serum carbon isotope ratio as a candidate predictive biomarker of the dietary animal protein ratio (animal protein/total protein) in a 15-day controlled feeding study of US adults

BACKGROUND

The serum natural abundance carbon isotope ratio (CIR) was recently identified as a candidate biomarker of animal protein intake in postmenopausal women. Such a biomarker would help clarify the relation between dietary protein source (plant or animal) and chronic disease risk.

OBJECTIVES

We aimed to evaluate the performance of the serum CIR as a biomarker of dietary protein source in a controlled feeding study of men and women of diverse age and BMI.

METHODS

We conducted a 15-d feeding study of 100 adults (age: 18-70 y, 55% women) in Phoenix, AZ. Participants were provided individualized diets that approximated habitual food intakes. Serum was collected at the end of the feeding period for biomarker measurements.

RESULTS

Median [IQR] animal protein intake was 67 g/d [55-88 g/d], which was 64% of total protein. The serum CIR was positively correlated with animal protein and inversely correlated with plant protein intake, leading to a strong correlation (r2 = 0.76) with the dietary animal protein ratio (APR; animal/total protein). Regressing serum CIR on the APR, serum nitrogen isotope ratio (NIR), gender, age, and body weight generated an R2 of 0.78. Following the measurement error model for predictive biomarkers, the resulting regression equation was then inverted to develop a calibrated biomarker equation for APR. Added sugars ratio (added/total sugars intake) and corn intakes also influenced the serum CIR but to a much lesser degree than the APR; variations in these intakes had only small effects on biomarker-estimated APR.

CONCLUSIONS

Based on our findings in this US cohort of mixed sex and age, we propose the serum CIR alongside NIR as a predictive dietary biomarker of the APR. We anticipate using this biomarker to generate calibrated estimates based on self-reported intake and ultimately to obtain more precise disease risk estimates according to dietary protein source.

Investigating the performance of 24-h urinary sucrose and fructose as a biomarker of total sugars intake in US participants - a controlled feeding study

BACKGROUND

Developing approaches for the objective assessment of sugars intake in population research is crucial for generating reliable disease risk estimates, and evidence-based dietary guidelines. Twenty-four-hour urinary sucrose and fructose (24uSF) was developed as a predictive biomarker of total sugars intake based on 3 UK feeding studies, yet its performance as a biomarker of total sugars among US participants is unknown.

OBJECTIVES

To investigate the performance of 24uSF as a biomarker of sugars intake among US participants, and to characterize its use.

METHODS

Ninety-eight participants, aged 18-70 y, consumed their usual diet under controlled conditions of a feeding study for 15 d, and collected 8 nonconsecutive 24-h urines measured for sucrose and fructose.

RESULTS

A linear mixed model regressing log 24uSF biomarker on log total sugars intake along with other covariates explained 56% of the biomarker variance. Total sugars intake was the strongest predictor in the model (Marginal R2 = 0.52; P <0.0001), followed by sex (P = 0.0002) and log age (P = 0.002). The equation was then inverted to solve for total sugars intake, thus generating a calibrated biomarker equation. Calibration of the biomarker produced mean biomarker-based log total sugars of 4.79 (SD = 0.59), which was similar to the observed log 15-d mean total sugars intake of 4.69 (0.35). The correlation between calibrated biomarker and usual total sugars intake was 0.59 for the calibrated biomarker based on a single biomarker measurement, and 0.76 based on 4 biomarker repeats spaced far apart.

CONCLUSIONS

In this controlled feeding study, total sugars intake was the main determinant of 24uSF confirming its utility as a biomarker of total sugars in this population. Next steps will include validation of stability assumptions of the biomarker calibration equation proposed here, which will allow its use as an instrument for dietary validation and measurement error correction in diet-disease association studies.

A randomized controlled phase III study of VB-111 combined with bevacizumab vs bevacizumab monotherapy in patients with recurrent glioblastoma (GLOBE)

Background

Ofranergene obadenovec (VB-111) is an anticancer viral therapy that demonstrated in a phase II study a survival benefit for patients with recurrent glioblastoma (rGBM) who were primed with VB-111 monotherapy that was continued after progression with concomitant bevacizumab.

Methods

This pivotal phase III randomized, controlled trial compared the efficacy and safety of upfront combination of VB-111 and bevacizumab versus bevacizumab monotherapy. Patients were randomized 1:1 to receive VB-111 10¹³ viral particles every 8 weeks in combination with bevacizumab 10 mg/kg every 2 weeks (combination arm) or bevacizumab monotherapy (control arm). The primary endpoint was overall survival (OS), and secondary endpoints were objective response rate (ORR) by Response Assessment in Neuro-Oncology (RANO) criteria and progression-free survival (PFS).

Results

Enrolled were 256 patients at 57 sites. Median exposure to VB-111 was 4 months. The study did not meet its primary or secondary goals. Median OS was 6.8 versus 7.9 months in the combination versus control arm (hazard ratio, 1.20; 95% CI: 0.91–1.59; P = 0.19) and ORR was 27.3% versus 21.9% (P = 0.26). A higher rate of grades 3–5 adverse events was reported in the combination arm (67% vs 40%), mainly attributed to a higher rate of CNS and flu-like/fever events. Trends for improved survival with combination treatment were seen in the subgroup of patients with smaller tumors and in patients who had a posttreatment febrile reaction.

Conclusions

In this study, upfront concomitant administration of VB-111 and bevacizumab failed to improve outcomes in rGBM. Change of treatment regimen, with the lack of VB-111 monotherapy priming, may explain the differences from the favorable phase II results.

Clinical trials registration

NCT02511405

Utilizing an interim futility analysis of the OVAL study (VB-111-701/GOG 3018) for potential reduction of risk: A phase III, double blind, randomized controlled trial of ofranergene obadenovec (VB-111) and weekly paclitaxel in patients with platinum resistant ovarian cancer

OBJECTIVE

Report the results from a preplanned interim analysis of a phase III, double blind, randomized controlled study of ofranergene obadenovec (VB-111), a targeted anti-cancer gene therapy, in combination with paclitaxel in patients with platinum resistant ovarian cancer (PROC).

METHODS

The OVAL (NCT03398655) study is an on-going study where patients are randomly assigned in a 1:1 ratio to weekly paclitaxel 80 mg/m² with VB-111 or placebo. The protocol specifies a pre-planned unblinded futility interim analysis of CA-125 response per GCIG criteria in the first 60 evaluable patients. The futility rule determined for this analysis was that the response rate of VB-111 must be greater than the response rate of placebo by at least 10% in order to continue the study. Coincident with the interim analysis, the blinded CA-125 response rate was estimated as a proportion of the first 60 evaluable patients with CA-125 response per GCIG criteria. Post-treatment fever is provided as a possible surrogate marker of VB-111 therapy activity.

RESULTS

The median age of the evaluable patients was 62 years (range 41-82); 97% had high-grade serous cancer; 58% had been treated with 3 or more previous lines of therapy, 70% received prior anti-angiogenic treatment, 43% received prior PARP inhibitors. CA-125 response in the VB-111 and weekly paclitaxel treated arm met the pre-specified interim criterion of an absolute advantage of 10% or higher compared to the control. Blinded results show a 53% CA-125 response rate (32/60) with 15% complete response (n=9). Assuming balanced randomization and an absolute advantage of 10% or higher to the VB-111 arm, it may be deducted that the response in the VB-111 treatment arm is 58% or higher. Among patients with post-treatment fever, the CA-125 response rate was 69%.

CONCLUSIONS

At the time of the interim analysis, response rate findings are comparable to the responses seen in a similar patient population in the phase I/II study. The independent data and safety monitoring committee (iDSMC) recommended continuing the OVAL trial as planned. No new safety signals were identified.

Multi-center nationwide comparison of seven serology assays reveals a SARS-CoV-2 non-responding seronegative subpopulation

BACKGROUND

An Israeli national taskforce performed a multi-center clinical and analytical validation of seven serology assays to determine their utility and limitations for SARS-CoV-2 diagnosis.

METHODS

Serology assays from Roche, Abbott, Diasorin, BioMerieux, Beckman-Coulter, Siemens, and an in-house RBD ELISA were included. Negative samples from 2391 individuals representative of the Israeli population, and 698 SARS-CoV-2 PCR positive patients, collected between March and May 2020, were analyzed.

FINDINGS

Immunoassays sensitivities between 81.5%-89.4% and specificities between 97.7%-100% resulted in a profound impact on the expected Positive Predictive Value (PPV) in low (<15%) prevalence scenarios. No meaningful increase was detected in the false positive rate in children compared to adults. A positive correlation between disease severity and antibody titers, and no decrease in antibody titers in the first 8 weeks after PCR positivity was observed. We identified a subgroup of symptomatic SARS-CoV-2 positive patients (~5% of patients), who remained seronegative across a wide range of antigens, isotypes, and technologies.

INTERPRETATION

The commercially available automated immunoassays exhibit significant differences in performance and expected PPV in low prevalence scenarios. The low false-positivity rate in under 20's suggests that cross-reactive immunity from previous CoV strains is unlikely to explain the milder disease course in children. Finding no decrease in antibody titers in the first 8 weeks is in contrast to some reports of short half-life for SARS-CoV-2 antibodies. The ~5% who were seronegative non-responders, using multiple assays in a population-wide manner, represents the proportion of patients that may be at risk for re-infection.

FUNDING

Israel Ministry of Health.

STRATOS guidance document on measurement error and misclassification of variables in observational epidemiology: Part 2-More complex methods of adjustment and advanced topics

We continue our review of issues related to measurement error and misclassification in epidemiology. We further describe methods of adjusting for biased estimation caused by measurement error in continuous covariates, covering likelihood methods, Bayesian methods, moment reconstruction, moment-adjusted imputation, and multiple imputation. We then describe which methods can also be used with misclassification of categorical covariates. Methods of adjusting estimation of distributions of continuous variables for measurement error are then reviewed. Illustrative examples are provided throughout these sections. We provide lists of available software for implementing these methods and also provide the code for implementing our examples in the Supporting Information. Next, we present several advanced topics, including data subject to both classical and Berkson error, modeling continuous exposures with measurement error, and categorical exposures with misclassification in the same model, variable selection when some of the variables are measured with error, adjusting analyses or design for error in an outcome variable, and categorizing continuous variables measured with error. Finally, we provide some advice for the often met situations where variables are known to be measured with substantial error, but there is only an external reference standard or partial (or no) information about the type or magnitude of the error.

STRATOS guidance document on measurement error and misclassification of variables in observational epidemiology: Part 1-Basic theory and simple methods of adjustment

Measurement error and misclassification of variables frequently occur in epidemiology and involve variables important to public health. Their presence can impact strongly on results of statistical analyses involving such variables. However, investigators commonly fail to pay attention to biases resulting from such mismeasurement. We provide, in two parts, an overview of the types of error that occur, their impacts on analytic results, and statistical methods to mitigate the biases that they cause. In this first part, we review different types of measurement error and misclassification, emphasizing the classical, linear, and Berkson models, and on the concepts of nondifferential and differential error. We describe the impacts of these types of error in covariates and in outcome variables on various analyses, including estimation and testing in regression models and estimating distributions. We outline types of ancillary studies required to provide information about such errors and discuss the implications of covariate measurement error for study design. Methods for ascertaining sample size requirements are outlined, both for ancillary studies designed to provide information about measurement error and for main studies where the exposure of interest is measured with error. We describe two of the simpler methods, regression calibration and simulation extrapolation (SIMEX), that adjust for bias in regression coefficients caused by measurement error in continuous covariates, and illustrate their use through examples drawn from the Observing Protein and Energy (OPEN) dietary validation study. Finally, we review software available for implementing these methods. The second part of the article deals with more advanced topics.

Safety and efficacy of VB-111, an anticancer gene therapy, in patients with recurrent glioblastoma: results of a phase I/II study

BACKGROUND

VB-111 is a non-replicating adenovirus carrying a Fas-chimera transgene, leading to targeted apoptosis of tumor vascular endothelium and induction of a tumor-specific immune response. This phase I/II study evaluated the safety, tolerability, and efficacy of VB-111 with and without bevacizumab in recurrent glioblastoma (rGBM).

METHODS

Patients with rGBM (n = 72) received VB-111 in 4 treatment groups: subtherapeutic (VB-111 dose escalation), limited exposure (LE; VB-111 monotherapy until progression), primed combination (VB-111 monotherapy continued upon progression with combination of bevacizumab), and unprimed combination (upfront combination of VB-111 and bevacizumab). The primary endpoint was median overall survival (OS). Secondary endpoints were safety, overall response rate, and progression-free survival (PFS).

RESULTS

VB-111 was well tolerated. The most common adverse event was transient mild-moderate fever. Median OS time was significantly longer in the primed combination group compared with both LE (414 vs 223 days; hazard ratio [HR], 0.48; P = 0.043) and unprimed combination (414 vs 141.5 days; HR, 0.24; P = 0.0056). Patients in the combination phase of the primed combination group had a median PFS time of 90 days compared with 60 in the LE group (HR, 0.36; P = 0.032), and 63 in the unprimed combination group (P = 0.72). Radiographic responders to VB-111 exhibited characteristic, expansive areas of necrosis in the areas of initial enhancing disease.

CONCLUSIONS

Patients with rGBM who were primed with VB-111 monotherapy that continued after progression with the addition of bevacizumab showed significant survival and PFS advantage, as well as specific imaging characteristics related to VB-111 mechanism of action. These results warrant further assessment in a randomized controlled study.

A modified Prevalence Incidence Analysis Model method may improve disease prevalence prediction

OBJECTIVES

The Prevalence Incidence Analysis Model method is used for predicting disease prevalence, using past data on incidence and relative survival. Our objective was to propose and evaluate a modified approach for choosing the Prevalence Incidence Analysis Model.

STUDY DESIGN AND SETTING

Instead of the standard approach using the likelihood ratio statistic, we find the model that predicts most successfully the prevalence in the last available Y years using data up to but not including those Y years and then use that model to predict future prevalence another Y years ahead using all the data. We also make an "alignment" adjustment using the last known prevalence level. We evaluate the relative performance of the modified and standard methods using data on cancer from Israel in 1983-2013.

RESULTS

In this example, the modified approach gave as good or better predictions than the standard. Using the modified approach, we forecast cancer prevalence in Israel for 2014-2024 to increase at a gradually accelerating rate from the current 10,000 per year to 12,000 per year by 2020, reaching a total of 380,000 by 2024.

CONCLUSION

The modified approach may offer improved forecasting, but further methodological work on forecasting cancer prevalence is needed.

Preconceptional diet quality is associated with birth outcomes among low socioeconomic status minority women in a high-income country

PURPOSE

Studies of the association between maternal nutrition and birth outcomes have investigated differing nutrients, maternal socioeconomic conditions, and timing within the reproductive cycle; and have produced inconsistent results. We evaluated the association of preconceptional maternal dietary intake with birth outcomes among low socioeconomic status ethnic minority women in a high-income country.

METHODS

In this prospective cohort study, habitual preconceptional dietary intake was assessed among pregnant Bedouin Arab women in Israel (n = 384), using a short culturally specific, targeted food frequency questionnaire. Multiple nutrients (protein, lysine, calcium, iron, zinc, folate, omega-3 fatty acids) were evaluated simultaneously via a diet quality score derived from principal component analysis. Multivariable logistic regression was used to test associations between the diet quality score and a composite adverse birth outcomes variable, including preterm birth, low birth weight and small for gestational age.

RESULTS

Sixty-nine women (18%) had adverse birth outcomes. Women with low preconceptional diet quality scores had low intakes of nutrient-rich plant foods, bioavailable micronutrients, and complete proteins. In multivariable analysis, a woman at the 10th percentile of the diet quality score had a 2.97 higher odds (95% CI 1.28-6.86) of an adverse birth outcome than a woman at the 90th percentile.

CONCLUSION

Low diet quality during the preconceptional period was associated with adverse birth outcomes among low socioeconomic status minority women in a high-income country. The results have implications for the development of appropriate intervention strategies to prevent adverse birth outcomes, and the promotion of adequate nutrition throughout the child-bearing years.

DNA Repair Biomarker for Lung Cancer Risk and its Correlation With Airway Cells Gene Expression

BACKGROUND

Improving lung cancer risk assessment is required because current early-detection screening criteria miss most cases. We therefore examined the utility for lung cancer risk assessment of a DNA Repair score obtained from OGG1, MPG, and APE1 blood tests. In addition, we examined the relationship between the level of DNA repair and global gene expression.

METHODS

We conducted a blinded case-control study with 150 non-small cell lung cancer case patients and 143 control individuals. DNA Repair activity was measured in peripheral blood mononuclear cells, and the transcriptome of nasal and bronchial cells was determined by RNA sequencing. A combined DNA Repair score was formed using logistic regression, and its correlation with disease was assessed using cross-validation; correlation of expression to DNA Repair was analyzed using Gene Ontology enrichment.

RESULTS

DNA Repair score was lower in case patients than in control individuals, regardless of the case's disease stage. Individuals at the lowest tertile of DNA Repair score had an increased risk of lung cancer compared to individuals at the highest tertile, with an odds ratio (OR) of 7.2 (95% confidence interval [CI] = 3.0 to 17.5; P < .001), and independent of smoking. Receiver operating characteristic analysis yielded an area under the curve  of 0.89 (95% CI = 0.82 to 0.93). Remarkably, low DNA Repair score correlated with a broad upregulation of gene expression of immune pathways in patients but not in control individuals.

CONCLUSIONS

The DNA Repair score, previously shown to be a lung cancer risk factor in the Israeli population, was validated in this independent study as a mechanism-based cancer risk biomarker and can substantially improve current lung cancer risk prediction, assisting prevention and early detection by computed tomography scanning.

Imputing missing time-dependent covariate values for the discrete time Cox model

We describe a procedure for imputing missing values of time-dependent covariates in a discrete time Cox model using the chained equations method. The procedure multiply imputes the missing values for each time-period in a time-sequential manner, using covariates from the current and previous time-periods as well as the survival outcome. The form of the outcome variable used in the imputation model depends on the functional form of the time-dependent covariate(s) and differs from the case of Cox regression with only baseline covariates. This time-sequential approach provides an approximation to a fully conditional approach. We illustrate the procedure with data on diabetics, evaluating the association of their glucose control with the risk of selected cancers. Using simulations we show that the suggested estimator performed well (in terms of bias and coverage) for completely missing at random, missing at random and moderate non-missing-at-random patterns. However, for very strong non-missing-at-random patterns, the estimator was seriously biased and the coverage was too low. The procedure can be implemented using multiple imputation with the Fully conditional Specification (FCS) method (MI procedure in SAS with FCS statement or similar packages in other software, e.g. MICE in R). For use with event times on a continuous scale, the events would need to be grouped into time-intervals.

Metformin Treatment and Cancer Risk: Cox Regression Analysis, With Time-Dependent Covariates, of 320,000 Persons With Incident Diabetes Mellitus

There is conflicting evidence regarding the association between metformin use and cancer risk in diabetic patients. During 2002–2012, we followed a cohort of 315,890 persons aged 21–87 years with incident diabetes who were insured by the largest health maintenance organization in Israel. We used a discrete form of weighted cumulative metformin exposure to evaluate the association of metformin with cancer incidence. This was implemented in a time-dependent covariate Cox model, adjusting for treatment with other glucose-lowering medications, as well as age, sex, ethnic background, socioeconomic status, smoking (for bladder and lung cancer), and parity (for breast cancer). We excluded from the analysis metformin exposure during the year before cancer diagnosis in order to minimize reverse causation of cancer on changes in medication use. Estimated hazard ratios associated with exposure to 1 defined daily dose of metformin over the previous 2–7 years were 0.98 (95% confidence interval (CI): 0.82, 1.18) for all-sites cancer (excluding prostate and pancreas), 1.05 (95% CI: 0.67, 1.63) for colon cancer, 0.98 (95% CI: 0.49, 1.97) for bladder cancer, 1.02 (95% CI: 0.59, 1.78) for lung cancer, and 0.88 (95% CI: 0.56, 1.39) for female breast cancer. Our results do not support an association between metformin treatment and the incidence of major cancers (excluding prostate and pancreas).

Measurement error correction and sensitivity analysis in longitudinal dietary intervention studies using an external validation study

In lifestyle intervention trials, where the goal is to change a participant's weight or modify their eating behavior, self-reported diet is a longitudinal outcome variable that is subject to measurement error. We propose a statistical framework for correcting for measurement error in longitudinal self-reported dietary data by combining intervention data with auxiliary data from an external biomarker validation study where both self-reported and recovery biomarkers of dietary intake are available. In this setting, dietary intake measured without error in the intervention trial is missing data and multiple imputation is used to fill in the missing measurements. Since most validation studies are cross-sectional, they do not contain information on whether the nature of the measurement error changes over time or differs between treatment and control groups. We use sensitivity analyses to address the influence of these unverifiable assumptions involving the measurement error process and how they affect inferences regarding the effect of treatment. We apply our methods to self-reported sodium intake from the PREMIER study, a multi-component lifestyle intervention trial.

Celiac plexus radiosurgery for pain management in advanced cancer patients: An international phase II trial

TPS466

Background: Many cancer patients, especially those with pancreatic cancer, suffer from severe back/epigastric pain. Contemporary approaches (opioids, celiac blocks, systemic chemotherapy) are often inadequate. This clinical trial investigates a new approach in which high-dose radiation (radiosurgery) is focused on the retroperitoneal celiac plexus nerve bundle. Preliminary results from a single institution pilot trial NCT02356406 are promising: pain relief is substantial and side effects minimal. The main aim of the trial is to establish safety/efficacy in the setting of an international multicenter study. Exploratory analyses will examine the relationship between pain reduction and subjects’ quality-of-life, functionality, and caregiver burden. Methods: Eligibility criteria include a diagnosis of metastatic/unresectable malignancy, uncontrolled pain defined as ≥ 5 on 11-point BPI-SF scale despite analgesic use, typical retroperitoneal pain syndrome, prognosis > 8 weeks, ECOG 0-2, anatomical involvement of the celiac plexus (e.g. any pancreatic cancer, or any other cancer involving the celiac trunk). Exclusion criteria include previous upper abdo. radiation. The intervention consists of a single 25 Gy radiation fraction delivered to the celiac plexus, using anterolateral aspect of the aorta from the 12th thoracic to 2nd lumbar vertebral body as a surrogate structure. The primary tumour may be irradiated at physicians’ discretion. Dose-painting technique limits dose to organs at risk. Pain intensity will be measured using Brief Pain Inventory Short Form (BPI-SF), and quality of life with FACT-Hep. The primary endpoint is complete or partial pain response, defined as a decrease between the score immediately before treatment and 3 weeks’ post-treatment. A change of two or more on the BPI 11-point pain scale is defined as clinically significant. Secondary endpoints include other BPI pain endpoints, pain at 6 weeks, analgesic use, toxicity (CTCAE v4.03), quality of life and functional measures. Analgesia is not restricted. Expected accrual is 100 subjects over three years. Supported by Gateway for Cancer Research, additional support from Israel Cancer Association. Clinical trial information: NCT03323489.

Phase I/II Study of Stem-Cell Transplantation Using a Single Cord Blood Unit Expanded Ex Vivo With Nicotinamide

PURPOSE

Increasing the number of hematopoietic stem and progenitor cells within an umbilical cord blood (UCB) graft shortens the time to hematopoietic recovery after UCB transplantation. In this study, we assessed the safety and efficacy of a UCB graft that was expanded ex vivo in the presence of nicotinamide and transplanted after myeloablative conditioning as a stand-alone hematopoietic stem-cell graft.

METHODS

Thirty-six patients with hematologic malignancies underwent transplantation at 11 sites.

RESULTS

The cumulative incidence of neutrophil engraftment at day 42 was 94%. Two patients experienced secondary graft failure attributable to viral infections. Hematopoietic recovery was compared with that observed in recipients of standard UCB transplantation as reported to the Center for International Blood and Marrow Transplant Research (n = 146). The median time to neutrophil recovery was 11.5 days (95% CI, 9 to 14 days) for recipients of nicotinamide-expanded UCB and 21 days (95% CI, 20 to 23 days) for the comparator ( P < .001). The median time to platelet recovery was 34 days (95% CI, 32 to 42 days) and 46 days (95% CI, 42 to 50 days) for the expanded and the comparator cohorts, respectively ( P < .001). The cumulative incidence of grade 2 to 4 acute graft-versus-host disease (GVHD) at day 100 was 44%, and grade 3 and 4 acute GVHD at day 100 was 11%. The cumulative incidence at 2 years of all chronic GVHD was 40%, and moderate/severe chronic GVHD was 10%. The 2-year cumulative incidences of nonrelapse mortality and relapse were 24% and 33%, respectively. The 2-year probabilities of overall and disease-free survival were 51% and 43%, respectively.

CONCLUSION

UCB expanded ex vivo with nicotinamide shortens median neutrophil recovery by 9.5 days (95% CI, 7 to 12 days) and median platelet recovery by 12 days (95% CI, 3 to 16.5 days). This trial establishes feasibility, safety, and efficacy of an ex vivo expanded UCB unit as a stand-alone graft.

A historical cohort study on glycemic-control and cancer-risk among patients with diabetes

AIMS

This population-based historical cohort study examined whether poor glycemic-control (i.e., high glucose and HbA1c blood levels) in patients with diabetes is associated with cancer-risk.

METHODS

From a large healthcare database, patients aged 21-89 years, diagnosed with diabetes before January 2002 (prevalent) or during 2002-2010 (incident), were followed for cancer during 2004-2012 (excluding cancers diagnosed within the first 2 years since diabetes diagnosis). Risks of selected cancers (all-sites, colon, breast, lung, prostate, pancreas and liver) were estimated according to glycemic-control in a Cox regression model with time-dependent covariates, adjusted for age, sex, ethnic origin, socioeconomic status, smoking and parity. Missing glucose or HbA1c values were imputed.

RESULTS

Among 440,000 patients included in our analysis, cancer was detected more than 2 years after diabetes diagnosis in 26,887 patients (6%) during the follow-up period. Associations of poor glycemic-control with all-sites cancer and most specific cancers were either null or only weak (hazard ratios (HRs) for a 1% HbA1c or a 30 mg/dl glucose increase between 0.94 and 1.09). Exceptions were pancreatic cancer, for which there was a strong positive association (HRs: 1.26-1.51), and prostate cancer, for which there was a moderate negative association (HRs: 0.85-0.96).

CONCLUSION

Overall, poor glycemic-control appears to be only weakly associated with cancer-risk, if at all. A substantial part of the positive association with pancreatic cancer is attributable to reverse causation, with the cancer causing poorer glycemic-control prior to its diagnosis. The negative association with prostate cancer may be related to lower PSA levels in those with poor control.

Combining a Food Frequency Questionnaire With 24-Hour Recalls to Increase the Precision of Estimation of Usual Dietary Intakes-Evidence From the Validation Studies Pooling Project

Improving estimates of individuals' dietary intakes is key to obtaining more reliable evidence for diet-health relationships from nutritional cohort studies. One approach to improvement is combining information from different self-report instruments. Previous work evaluated the gains obtained from combining information from a food frequency questionnaire (FFQ) and multiple 24-hour recalls (24HRs), based on assuming that 24HRs provide unbiased measures of individual intakes. Here we evaluate the same approach of combining instruments but base it on the better assumption that recovery biomarkers provide unbiased measures of individual intakes. Our analysis uses data from the 5 large validation studies included in the Validation Studies Pooling Project: the Observing Protein and Energy Nutrition Study (1999-2000), the Automated Multiple-Pass Method validation study (2002-2004), the Energetics Study (2006-2009), the Nutrition Biomarker Study (2004-2005), and the Nutrition and Physical Activity Assessment Study (2007-2009). The data included intakes of energy, protein, potassium, and sodium. Under a time-varying usual-intake model analysis, the combination of an FFQ with 4 24HRs improved correlations with true intake for predicted protein density, potassium density, and sodium density (range, 0.39-0.61) in comparison with use of a single FFQ (range, 0.34-0.50). Absolute increases in correlation ranged from 0.02 to 0.26, depending on nutrient and sex, with an average increase of 0.14. Based on unbiased recovery biomarker evaluation for these nutrients, we confirm that combining an FFQ with multiple 24HRs modestly improves the accuracy of estimates of individual intakes.

Newly diagnosed type 2 diabetes may serve as a potential marker for pancreatic cancer

Pancreatic cancer has an extremely highly case fatality. Diabetes is a well-established strong risk factor for pancreatic cancer. Compared with a nondiabetic population, we previously reported a 15- and 14-fold greater risk for detecting pancreatic cancer during the first year after diagnosing diabetes in adult women and men, respectively, which dropped during the second year to 5.4-fold and 3.5-fold, respectively, and stabilized around 3-fold for the rest of the 11-year follow-up in our historical cohort. The population attributable risk during the 11-year period was 13.3% and 14.1% in prevalent diabetic women and men, respectively. This means that one out of about every 8 patients diagnosed with pancreatic cancer has been previously diagnosed with diabetes. The globally high prevalence of diabetes and the aggravating implications of a delayed pancreatic cancer diagnosis call for newly-onset diabetes to be considered a potential marker for an underlying pancreatic cancer and addressed accordingly.

Disease Management plus Recommended Care versus Recommended Care Alone for Ambulatory Patients with Chronic Obstructive Pulmonary Disease

Rationale: The efficacy of disease management programs in the treatment of patients with chronic obstructive pulmonary disease (COPD) remains uncertain.Objectives: To study the effect of disease management (DM) added to recommended care (RC) in ambulatory patients with COPD.Measurements and Main Results: In this trial, 1,202 patients with COPD (age, ≥40 yr), with moderate to very severe airflow limitation were randomly assigned either to DM plus RC (study intervention) or to RC alone (control intervention). RC included follow-up by pulmonologists, inhaled long-acting bronchodilators and corticosteroids, smoking cessation intervention, nutritional advice and psychosocial support when indicated, and supervised physical activity sessions. DM, delivered by trained nurses during patients' visits to the designated COPD centers and by remote contacts with the patients between these visits, included patient self-care education, monitoring patients' symptoms and adherence to treatment, provision of advice in case of acute disease exacerbation, and coordination of care vis-à-vis other healthcare providers. The primary composite endpoint was first hospital admission for respiratory symptoms or death from any cause. During 3,537 patient-years, 284 patients (47.2%) in the control group and 264 (44.0%) in the study intervention group had a primary endpoint event. The median (range) time elapsed until a primary endpoint event was 1.0 (0-4.0) years among patients assigned to the study intervention and 1.1 (0-4.1) years among patients assigned to the control intervention; adjusted hazard ratio, 0.92 (95% confidence interval, 0.77-1.08).Conclusions: DM added to RC was not superior to RC alone in delaying first hospital admission or death among ambulatory patients with COPD.

Diminishing benefit of smoking cessation medications during the first year: a meta-analysis of randomized controlled trials

BACKGROUND AND AIMS

Although smoking cessation medications have shown effectiveness in increasing abstinence in randomized controlled trials (RCTs), it is unclear to what extent benefits persist over time. This paper assesses whether the benefits of smoking cessation medications decline over the first year.

METHODS

We selected studies from three systematic reviews published by the Cochrane Collaboration. RCTs of first-line smoking cessation medications, with 6- and 12-month follow-up, were eligible for inclusion. Meta-analysis was used to synthesize information on sustained abstinence (SA) at 6 versus 12 months and 3 versus 6 months, using the risk difference (RD) ('net benefit') between intervention and control group quit rates, the relative risk (RR) and the odds ratio (OR).

RESULTS

Sixty-one studies (27 647 participants) were included. Fewer than 40% of intervention group participants were sustained abstinent at 3 months (bupropion: 37.1%; nicotine replacement therapy (NRT): 34.8%; varenicline: 39.3%); approximately a quarter were sustained abstinent at 6 months (bupropion: 25.9%; NRT: 26.6%; varenicline: 25.4%), and approximately a fifth were sustained abstinent at 12 months (bupropion: 19.9%; NRT: 19.8%%; varenicline: 18.7%). There was only a small decline in RR (3 months: 1.95 [95% confidence interval (CI) = 1.74-2.18, P < 0.0001]; 6 months: 1.87 (95% CI = 1.67-2.08 P < 0.0001); 12 months: 1.75 (95% CI = 1.56-1.95, P < 0.0001) between intervention and control groups over time, but a substantial decline in net benefit [3 months: RD = 17.3% (14.5-20.1%); 6 months: RD = 11.8% (10.0-13.7%); 12 months: RD = 8.2% (6.8-9.6%)]. The decline in net benefit was statistically significant between 3 and 6 [RD = 4.95% (95% CI = 3.49-6.41%), P < 0.0001] and 6 and 12 months [RD = 3.00% (95% CI = 2.36%-3.64%), P < 0.0001)] for medications combined and individual medications.

CONCLUSIONS

The proportion of smokers who use smoking cessation medications who benefit from doing so decreases during the course of the first year, but a net benefit still remains at 12 months.

Cancer risk among Holocaust survivors in Israel-A nationwide study

BACKGROUND

Holocaust survivors during World War II were exposed to various factors that are associated with cancer risk. The objective of this study was to determine whether Holocaust survivors had an increased risk for developing cancer.

METHODS

The study population included 152,622 survivors. The main analysis was based on a comparison between individuals who were entitled to compensation for suffering persecution during the war and individuals who were denied such compensation. A complementary analysis compared survivors who were born in countries governed by Nazi Germany with survivors born in nonoccupied countries. A Cox proportional hazards model was used, with the time at risk of cancer development starting on either January 1, 1960, or the date of immigration to the date of cancer diagnosis or death or the date of last follow-up (December 31, 2006).

RESULTS

Cancer was diagnosed in 22.2% of those who were granted compensation versus 16% of those who were denied compensation (P < .0001). Adjusting for birth cohort, sex, country of origin, and period of immigration, both analyses revealed significant increased risks of developing cancer in those who were exposed. For those who were granted versus denied compensation, the hazard ratios were 1.06 (P < .001) for all sites, 1.12 (P = .07) for colorectal cancer, and 1.37 (P = .008) for lung cancer. For those born in occupied countries versus nonoccupied countries, the hazard ratios were 1.08 (P < .001), 1.08 (P = .003), and 1.12 (P = .02), respectively.

CONCLUSIONS

The current results, based on a large cohort of Holocaust survivors who were exposed to a variety of severe deprivations, add to the conflicting and sparse knowledge on this issue and support the notion that this group has a small but consistent increase in cancer development. Cancer 2017;123:3335-45. © 2017 American Cancer Society.

Evaluation of the 24-Hour Recall as a Reference Instrument for Calibrating Other Self-Report Instruments in Nutritional Cohort Studies: Evidence From the Validation Studies Pooling Project

Calibrating dietary self-report instruments is recommended as a way to adjust for measurement error when estimating diet-disease associations. Because biomarkers available for calibration are limited, most investigators use self-reports (e.g., 24-hour recalls (24HRs)) as the reference instrument. We evaluated the performance of 24HRs as reference instruments for calibrating food frequency questionnaires (FFQs), using data from the Validation Studies Pooling Project, comprising 5 large validation studies using recovery biomarkers. Using 24HRs as reference instruments, we estimated attenuation factors, correlations with truth, and calibration equations for FFQ-reported intakes of energy and for protein, potassium, and sodium and their densities, and we compared them with values derived using biomarkers. Based on 24HRs, FFQ attenuation factors were substantially overestimated for energy and sodium intakes, less for protein and potassium, and minimally for nutrient densities. FFQ correlations with truth, based on 24HRs, were substantially overestimated for all dietary components. Calibration equations did not capture dependencies on body mass index. We also compared predicted bias in estimated relative risks adjusted using 24HRs as reference instruments with bias when making no adjustment. In disease models with energy and 1 or more nutrient intakes, predicted bias in estimated nutrient relative risks was reduced on average, but bias in the energy risk coefficient was unchanged.

Invited Commentary: The Contribution to the Field of Nutritional Epidemiology of the Landmark 1985 Publication by Willett et al

The semiquantitative food frequency questionnaire (FFQ) has been the primary source of dietary exposure data in epidemiology for decades. Although frequency instruments had been evaluated before the 1985 publication "Reproducibility and Validity of a Semiquantitative Food Frequency Questionnaire" by Willett et al. (Am J Epidemiol. 1985;122(1):51-65), that paper was the prototype for the development and validation of what was then a highly innovative method for collecting dietary data. This approach was adopted in nearly all subsequent cohort studies of diet and disease. The paper also catalyzed an extended scientific discourse regarding methods for validation, energy adjustment, and measurement error. It is now well established that data from FFQs and other self-reported dietary assessment instruments have both value and error and that this error should be considered in the analysis and interpretation of findings, including sensitivity analyses in which adjustment for measurement error is explored. Advances in technology make it feasible to consider collecting multiple granular short-term instruments such as recalls or records over time in addition to FFQs among all participants in large cohort studies; both provide valuable information. Without a doubt, the 1985 publication by Willett et al. provided the foundation that propelled the field of nutritional epidemiology forward, and it continues to be relevant today.

Treatment through progression with ofranogene obadenovec (VB-111), an anti-cancer viral therapy, significantly attenuates tumor growth in recurrent GBM: Individual phase 2 patient data

2055

Background: Ofranergene obadenovec (VB-111) is a viral cancer-therapy with a dual mechanism: vascular disruption and induction of a tumor directed immune response. Prolongation of overall survival (OS) has been shown in recurrent glioblastoma (rGBM) patients treated through progression with VB-111 in combination with bevacizumab (BEV) compared to historical controls and to patients with limited exposure (LE) to VB-111. Here we present individual patient tumor growth data. Methods: VB-111 was administered at 1x1013viral particles bimonthly until progression, followed by BEV standard of care (LE cohort). The protocol was amended to allow treatment through progression (TThP) with VB-111 bimonthly, with the addition of BEV 10mg/Kg biweekly, until further progression (TThP cohort). Tumor dimensions were assessed q2 months by MRI locally and by an independent central lab. The slope of the log tumor measurement over time was calculated for each patient, average slopes were compared across therapy groups using the Wilcoxon Rank Sum test. Results: 46 patients received up to 13 doses of VB-111. All started with VB-111 monotherapy. 22 were included in the LE cohort; 24 in the TThP cohort. Cohorts were comparable by measures of age, performance status, prior lines of therapy, baseline tumor dimensions and progression-free-survival. Spider diagrams demonstrate similar rapid tumor growth in both LE and TThP cohorts during the VB-111 monotherapy period (local site data; median % increase (MPI) per 30d: 14.8 vs 14.1, p = 0.98). In the TThP cohort, growth was attenuated after the 1stprogression, compared to the preceding VB-111 monotherapy period (MPI: 0.6 vs 14.1, p = 0.0032); responses were seen, including 2 complete responses (CR), one patient remaining in CR over 3 years. A similar attenuation was seen in central lab tumor measurements. Conclusions: Treatment through progression with VB-111 in combination with BEV induced durable tumor growth attenuation, which was associated with prolonged OS of 15 months in patients with rGBM. The GLOBE phase 3 randomized controlled trial of VB-111 in rGBM is currently underway. Clinical trial information: NCT01260506.

Disease management in the treatment of patients with chronic heart failure who have universal access to health care: a randomized controlled trial

BACKGROUND

The efficacy of disease management programs in improving the outcome of heart failure patients remains uncertain and may vary across health systems. This study explores whether a countrywide disease management program is superior to usual care in reducing adverse health outcomes and improving well-being among community-dwelling adult patients with moderate-to-severe chronic heart failure who have universal access to advanced health-care services and technologies.

METHODS

In this multicenter open-label trial, 1,360 patients recruited after hospitalization for heart failure exacerbation (38%) or from the community (62%) were randomly assigned to either disease management or usual care. Disease management, delivered by multi-disciplinary teams, included coordination of care, patient education, monitoring disease symptoms and patient adherence to medication regimen, titration of drug therapy, and home tele-monitoring of body weight, blood pressure and heart rate. Patients assigned to usual care were treated by primary care practitioners and consultant cardiologists. The primary composite endpoint was the time elapsed till first hospital admission for heart failure exacerbation or death from any cause. Secondary endpoints included the number of all hospital admissions, health-related quality of life and depression during follow-up. Intention-to-treat comparisons between treatments were adjusted for baseline patient data and study center.

RESULTS

During the follow-up, 388 (56.9%) patients assigned to disease management and 387 (57.1%) assigned to usual care had a primary endpoint event. The median (range) time elapsed until the primary endpoint event or end of study was 2.0 (0-5.0) years among patients assigned to disease management, and 1.8 (0-5.0) years among patients assigned to usual care (adjusted hazard ratio, 0.908; 95% confidence interval, 0.788 to 1.047). Hospital admissions were mostly (70%) unrelated to heart failure. Patients assigned to disease management had a better health-related quality of life and a lower depression score during follow-up.

CONCLUSIONS

This comprehensive disease management intervention was not superior to usual care with respect to the primary composite endpoint, but it improved health-related quality of life and depression. A disease-centered approach may not suffice to make a significant impact on hospital admissions and mortality in patients with chronic heart failure who have universal access to health care.

CLINICAL TRIAL REGISTRATION

Clinicaltrials.gov identifier: NCT00533013 . Trial registration date: 9 August 2007. Initial protocol release date: 20 September 2007.