Life expectancy in multimorbid older adults: Why it matters for preventive care

Multimorbidity is highly prevalent among older adults and associated with a shorter life expectancy. Many guidelines recommend tailoring preventive care of multimorbid people according to life expectancy. Indeed, there is a time lag between a preventive care intervention and the expected potential benefit, and patients with a relatively short life expectancy might not have the time to benefit from the preventive care intervention. Further, both patients and health care providers tend to overestimate benefits and underestimate risks of interventions. It is therefore necessary to have a valid index for mortality prediction in multimorbid patients, but there is no life expectancy estimator designed and recommended for this population. The paper describes the development and internal validation of a new life expectancy estimator. In this presentation, we focus on the importance of life expectancy estimation in multimorbid older adults: Why does it matter in this population? What is the time lag to benefit of a preventive intervention, e.g., cancer screening? What is the state in this field, in research and clinical practice? How could tailoring preventive care to life expectancy improve patient outcomes?

Intergenerational education and premature mortality: a registry population-based study

Inequalities in premature mortality due to individual's attained education are well documented. Intergenerational educational trajectories, whereby both parental and individual education may affect mortality, have received less attention. Our aim was to assess the effect of intergenerational educational trajectories on sex- and cause-specific risks of chronic disease-related premature mortality in Switzerland. Data were from 695,972 individuals born between 1971 and 1980, who were followed from adolescence (10-19y) to mid-life (38-47y) in the Swiss National Cohort, a registry population-based study. Educational trajectories were categorized into four levels: High-High, High-Low, Low-High, Low-Low, which corresponded to the sequence of parental-individual attained education (exposure). Cause of death categories were cardiovascular disease (CVD), cancer, substance use and all other chronic diseases (outcome). We implemented a counterfactual-based framework to quantify inequalities and ran negative outcome controls to triangulate findings. Overall, inequalities were negligible for women and substantial for men, particularly in CVD and substance use deaths. Specifically, inequalities in CVD were negligible by age 30, while by age 45 inequalities due to a High-Low or Low-Low trajectory corresponded to 229 (95% confidence interval (CI): 99, 381) additional CVD deaths per 100,000 persons compared to a High-High trajectory. Inequalities in substance use deaths due to a High-Low trajectory corresponded to 106 (95% CI: 47, 208) additional deaths per 100,000 persons compared to a High-High trajectory by age 30, and increased afterwards. We identified sex- and cause-specific groups at high-risk of premature mortality, and life periods when inequalities due to both parental and individual education arise. Prioritization of prevention strategies in those life periods and groups may help reduce educational inequalities in chronic disease-related premature mortality.

Development and internal validation of a new life expectancy estimator for multimorbid older adults

Background

Multimorbidity is highly prevalent among older adults and associated with a shorter life expectancy. Many guidelines recommend tailoring preventive care of multimorbid people according to life expectancy. Indeed, patients with a relatively short life expectancy might not have the time to benefit from a preventive care intervention. Our objective was therefore to develop and internally validate a life expectancy estimator for older multimorbid adults.

Methods

We analysed data of the OPERAM (OPtimising thERapy to prevent Avoidable hospital admissions in Multimorbid older people) cohort study in Bern, Switzerland. 822 hospitalized participants aged 70 years old or more, with multimorbidity (3 or more chronic medical conditions), and polypharmacy (use of 5 drugs or more for >30 days) were included. Our main outcome was time to all-cause mortality assessed during 3 years of follow-up. Candidate predictors included demographic variables (age, sex), clinical characteristics (Charlson-Comorbidity-Index, number of drugs, body mass index, weight loss), smoking, functional status variables (Barthel-Index, falls, nursing home residence), and hospitalization. We internally validated and optimism corrected the model using bootstrapping techniques. We transformed the 3-year mortality prognostic index into a life expectancy estimator using the Gompertz survival function.

Results

At baseline, the participants (58% men) had a median age of 79 years (min: 70; max: 99). They took daily a median of 10 chronic medications (min: 5; max 38). During 3 years of follow-up, 292 participants (36%) died. The analysis is ongoing and results will be presented at the congress.

Conclusions

A life expectancy estimator eventually helps personalising care to prevent under- and overuse of preventive care in the growing older population.

Key messages

SARS-CoV-2 infection among employees working from home and on site: An occupational study in Switzerland

During the COVID-19 pandemic, many companies implemented working from home to mitigate the spread of the disease among their employees. Using data from Corona Immunitas Nestlé, a seroepidemiological study conducted among employees from two Nestlé sites in Switzerland, we aimed to investigate whether there was a difference in SARS-CoV-2 infection rates between employees working most of the time from home and employees mobilized in a workplace equipped with a specialized occupational safety unit and strict sanitary measures. We also investigated whether this association was modified by household size, living with children, vulnerability, worries about an infection, and worries about adverse health consequences if infected. Data were collected between 8 December 2020, and 11 February 2021. Previous SARS-CoV-2 infections were ascertained by the presence of anti-SARS-CoV-2 IgG antibodies in the blood. Of the 425 employees included (53% women; mean age 42 years ranging between 21 and 64 years), 37% worked most of the time from home in 2020 and 16% had been infected with SARS-CoV-2. Participants who worked most of the time from home in 2020 had slightly higher odds of being infected with SARS-CoV-2 compared to participants who never or only sometimes worked from home (adjusted OR 1.29, 95% CI 0.73-2.27). The association was stronger in participants living alone or with one other person (adjusted OR 2.62, 95% CI 1.13-6.25). Among participants living with two or more other persons (adjusted OR 0.66, 95% CI 0.30-1.39) and among vulnerable participants (adjusted OR 0.53, 95% CI 0.13-1.93), working from home tended to be associated with lower odds of infection. In conclusion, in a context of strict sanitary measures implemented in the workplace, employees working from home did not seem to be at lower risk of infection compared to those working on site, especially if living alone or with one other person.

Development and validation of a new prognostic index for mortality risk in multimorbid adults

Context

Multimorbidity is highly prevalent among older adults and associated with a high mortality. Prediction of mortality in multimorbid people would be clinically useful but there is no mortality risk index designed for this population. Our objective was therefore to develop and internally validate a 1-year mortality prognostic index for older multimorbid adults.

Methods

We analysed data of the OPERAM cohort study in Bern, Switzerland, including 822 adults aged 70 years or more with multimorbidity (3 or more chronic medical conditions) and polypharmacy (use of 5 drugs or more for >30 days). Time to all-cause mortality was assessed up to 1 year of follow-up. We performed a parametric Weibull regression model with backward stepwise selection to identify mortality risk predictors. The model was internally validated and optimism corrected using bootstrapping techniques. We derived a point-based risk score from the regression coefficients. Calibration and discrimination were assessed by the calibration slope and C statistic.

Results

805 participants were included in the analysis. During 1-year of follow-up, 158 participants (20%) had died. Age, Charlson-Comorbidity-Index, number of drugs, body mass index, number of hospitalizations, Barthel-Index (functional impairment), and nursing home residency were predictors of 1-year mortality in a multivariable model. Using these variables, the 1-year probability of dying could be predicted with an optimism-corrected C statistic of 0.70. The optimism-corrected calibration slope was 0.93. Based on the derived point-based risk score to predict mortality risk, 7% of the patients classified at low-risk of mortality, 19% at moderate-risk, and 37% at high-risk died after one year of follow-up. A simpler mortality score, without the Charlson-Comorbidity-Index and Barthel-Index, showed reduced discriminative power (optimism-corrected C statistic: 0.59) compared to the full score.

Conclusion

We developed and internally validated a mortality risk index including for the first-time specific predictors for multimorbid adults. This new 1-year mortality prediction point-based score allowed to classify multimorbid older patients into three categories of increasing risk of mortality. Further validation of the score among various populations of multimorbid patients is needed before its implementation into practice.

Interventions to Decrease Carotid-Intima Media Thickness in Children and Adolescents With Type 1 Diabetes: A Systematic Review and Meta-Analysis

Introduction

Hyperglycemia is associated with a higher cardiovascular risk, as evidenced by increased carotid-intima media thickness (CIMT) in youth with diabetes. We conducted a systematic review and meta-analysis to assess the effect of pharmacological or non-pharmacological interventions on CIMT in children and adolescents with prediabetes or diabetes.

Methods

We conducted systematic searches of MEDLINE, EMBASE, and CENTRAL, together with supplementary searches in trial registers and other sources for studies completed up to September 2019. Interventional studies assessing ultrasound CIMT in children and adolescents with prediabetes or diabetes were considered for inclusion. Where appropriate, data were pooled across studies using random-effect meta-analysis. Quality was assessed using The Cochrane Collaboration’s risk-of-bias tool and a CIMT reliability tool.

Results

Six studies involving 644 children with type 1 diabetes mellitus were included. No study involved children with prediabetes or type 2 diabetes. Three randomized controlled trials (RCTs) evaluated the effects of metformin, quinapril, and atorvastatin. Three non-randomized studies, with a before-and-after design, evaluated the effects of physical exercise and continuous subcutaneous insulin infusion (CSII). The mean CIMT at baseline ranged from 0.40 to 0.51 mm. The pooled difference in CIMT was -0.01 mm (95% CI: -0.04 to 0.01) for metformin compared to placebo (2 studies; 135 participants; I2: 0%). The difference in CIMT was -0.01 mm (95% CI: -0.03 to 0.01) for quinapril compared to placebo (1 study; 406 participants). The mean change from baseline in CIMT was -0.03 mm (95% CI: -0.14 to 0.08) after physical exercise (1 study; 7 participants). Inconsistent results were reported for CSII or for atorvastatin. CIMT measurement was rated at a higher quality on all reliability domains in 3 (50%) studies. The confidence in results is limited by the low number of RCTs and their small sample sizes, as well as the high risk of bias in before-and-after studies.

Conclusions

Some pharmacological interventions may decrease CIMT in children with type 1 diabetes. However, there is great uncertainty with respect to their effects and no strong conclusions can be drawn. Further evidence from larger RCTs is required.

Systematic Review Registration

PROSPERO, CRD42017075169

Is living in a household with children associated with SARS-CoV-2 seropositivity in adults? Results from the Swiss national seroprevalence study Corona Immunitas

BACKGROUND

We aimed to determine whether living in a household with children is associated with SARS-CoV-2 seropositivity in adults and investigated interacting factors that may influence this association.

METHODS

SARS-CoV-2 serology testing was performed in randomly selected individuals from the general population between end of October 2020 and February 2021 in 11 cantons in Switzerland. Data on sociodemographic and household characteristics, employment status, and health-related history was collected using questionnaires. Multivariable logistic regression was used to examine the association of living with children <18 years of age (number, age group) and SARS-CoV-2 seropositivity. Further, we assessed the influence of reported non-household contacts, employment status, and gender.

RESULTS

Of 2393 working age participants (18-64 years), 413 (17.2%) were seropositive. Our results suggest that living with children and SARS-CoV-2 seropositivity are likely to be associated (unadjusted odds ratio (OR) 1.22, 95% confidence interval [0.98-1.52], adjusted OR 1.25 [0.99-1.58]). A pattern of a positive association was also found for subgroups of children aged 0-11 years (OR 1.21 [0.90-1.60]) and 12-17 years (OR 1.14 [0.78-1.64]). Odds of seropositivity were higher with more children (OR 1.14 per additional child [1.02-1.27]). Men had higher risk of SARS-CoV-2 infection when living with children than women (interaction: OR 1.74 [1.10-2.76]).

CONCLUSIONS

In adults from the general population living with children seems associated with SARS-CoV-2 seropositivity. However, child-related infection risk is not the same for every subgroup and depends on factors like gender. Further factors determining child-related infection risk need to be identified and causal links investigated.

TRIAL REGISTRATION

https://www.isrctn.com/ISRCTN18181860 .

The Corona Immunitas Digital Follow-Up eCohort to Monitor Impacts of the SARS-CoV-2 Pandemic in Switzerland: Study Protocol and First Results

Objectives: To describe the rationale, organization, and procedures of the Corona Immunitas Digital Follow-Up (CI-DFU) eCohort and to characterize participants at baseline.

Methods: Participants of Corona Immunitas, a population-based nationwide SARS-CoV-2 seroprevalence study in Switzerland, were invited to join the CI-DFU eCohort in 11 study centres. Weekly online questonnaires cover health status changes, prevention measures adherence, and social impacts. Monthly questionnaires cover additional prevention adherence, contact tracing apps use, vaccination and vaccine hesitancy, and socio-economic changes.

Results: We report data from the 5 centres that enrolled in the CI-DFU between June and October 2020 (covering Basel City/Land, Fribourg, Neuchâtel, Ticino, Zurich). As of February 2021, 4636 participants were enrolled and 85,693 weekly and 27,817 monthly questionnaires were collected. Design-based oversampling led to overrepresentation of individuals aged 65+ years. People with higher education and income were more likely to enroll and be retained.

Conclusion: Broad enrolment and robust retention of participants enables scientifically sound monitoring of pandemic impacts, prevention, and vaccination progress. The CI-DFU eCohort demonstrates proof-of-principle for large-scale, federated eCohort study designs based on jointly agreed principles and transparent governance.

How blood pressure predicts frailty transitions in older adults in a population-based cohort study: a multi-state transition model

Background

Low blood pressure (BP) is associated with frailty in older adults. Our aim was to explore how BP predicts transitions between frailty states.

Methods

We used data from the Lausanne cohort Lc65+, a population-based cohort of older adults randomly drawn from a population registry in Switzerland, in 2004, 2009 and 2014. BP was measured using a clinically validated oscillometric automated device and frailty was defined using Fried’s phenotype, every 3 years. We used an illness-death discrete multi-state Markov model to estimate hazard ratios of forward and backward transitions between frailty states (outcome) in relation to BP categories (predictor of interest) with adjustment for sex, age and antihypertensive medication (other predictors).

Results

Among 4200 participants aged 65–70 years (58% female) at baseline, 70% were non-frail, 27% pre-frail and 2.0% frail. Over an average follow-up of 5.8 years, 2422 transitions were observed, with 1575 (65%) forward and 847 (35%) backward. Compared with systolic BP (SBP) <130 mmHg, the hazard ratio (95% confidence interval) of the transition from non-frail to pre-frail was 0.86 (0.74 to 1.00) for SBP 130–150 mmHg, and 0.89 (0.74 to 1.06) for SBP ≥150 mmHg. Compared with SBP <130 mmHg, the hazard ratio of the transition from pre-frail to frail was 0.71 (0.50 to 1.01) for SBP 130–150 mmHg, and 0.90 (0.62 to 1.32) for SBP ≥150 mmHg. Diastolic BP was a weaker predictor of forward transitions.

Conclusions

BP categories had no strong relationship with either forward transitions or backward transitions in frailty states. If our findings are confirmed with greater precision and assuming a causal relationship, they would suggest that there is no well-defined optimal BP level to prevent frailty among older adults.

Development and validation of a life expectancy estimator for multimorbid older adults: a cohort study protocol

BACKGROUND

Older multimorbid adults have a high risk of mortality and a short life expectancy (LE). Providing high-value care and avoiding care overuse, including of preventive care, is a serious challenge among multimorbid patients. While guidelines recommend to tailor preventive care according to the estimated LE, there is no tool to estimate LE in this specific population. Our objective is therefore to develop an LE estimator for older multimorbid adults by transforming a mortality prognostic index, which will be developed and internally validated in a prospective cohort.

METHODS AND ANALYSIS

We will analyse data of the Optimising Therapy to Prevent Avoidable Hospital Admissions in Multimorbid Older People cohort study in Bern, Switzerland. 822 participants were included at hospitalisation with age of 70 years or older, multimorbidity (three or more chronic medical conditions) and polypharmacy (use of five drugs or more for >30 days). All-cause mortality will be assessed during 3 years of follow-up. We will apply a flexible parametric survival model with backward stepwise selection to identify the mortality risk predictors. The model will be internally validated using bootstrapping techniques. We will derive a point-based risk score from the regression coefficients. We will transform the 3-year mortality prognostic index into an LE estimator using the Gompertz survival function. We will perform a qualitative assessment of the clinical usability of the LE estimator and its application. We will conduct the development and validation of the mortality prognostic index following the Prognosis Research Strategy (PROGRESS) framework and report it following the Transparent Reporting of a Multivariable Prediction Model for Individual Prognosis or Diagnosis (TRIPOD) statement.

ETHICS AND DISSEMINATION

Written informed consent by patients themselves or, in the case of cognitive impairment, by a legal representative, was required before enrolment. The local ethics committee (Kantonale Ethikkommission Bern) has approved the study. We plan to publish the results in peer-reviewed journals and present them at national and international conferences.

Corona Immunitas: study protocol of a nationwide program of SARS-CoV-2 seroprevalence and seroepidemiologic studies in Switzerland

OBJECTIVES

Seroprevalence studies to assess the spread of SARS-CoV-2 infection in the general population and subgroups are key for evaluating mitigation and vaccination policies and for understanding the spread of the disease both on the national level and for comparison with the international community.

METHODS

Corona Immunitas is a research program of coordinated, population-based, seroprevalence studies implemented by Swiss School of Public Health (SSPH+). Over 28,340 participants, randomly selected and age-stratified, with some regional specificities will be included. Additional studies in vulnerable and highly exposed subpopulations are also planned. The studies will assess population immunological status during the pandemic.

RESULTS

Phase one (first wave of pandemic) estimates from Geneva showed a steady increase in seroprevalence up to 10.8% (95% CI 8.2-13.9, n = 775) by May 9, 2020. Since June, Zurich, Lausanne, Basel City/Land, Ticino, and Fribourg recruited a total of 5973 participants for phase two thus far.

CONCLUSIONS

Corona Immunitas will generate reliable, comparable, and high-quality serological and epidemiological data with extensive coverage of Switzerland and of several subpopulations, informing health policies and decision making in both economic and societal sectors. ISRCTN Registry: https://www.isrctn.com/ISRCTN18181860 .

Estimating life expectancy among older multimorbid adults to personalize preventive care

Background

Providing high value care and avoiding care overuse is a challenge among older multimorbid adults. There is evidence on benefits and harms of cancer screening and cardiovascular diseases (CVD) preventive treatment up to the age of 75. However, this evidence is not directly applicable to older multimorbid patients. Because each cancer and CVD preventive care has a specific lagtime to benefit, many guidelines recommend tailoring preventive care according to the estimated life expectancy (LE). However, there is no tool to estimate LE among multimorbid patients. Our objectives are therefore to develop new mortality risk prognostic indices and to derive a new LE estimator, what will help clinicians tailoring preventive care in older multimorbid adults.

Methods and Results

We conduct a prospective cohort study by extending the follow-up of 822 patients in Bern, Switzerland, included in the OPtimising thERapy to prevent Avoidable hospital admissions in Mulitmorbid older people (OPERAM) study over 3 years. Detailed information about cancer screening and CVD preventive treatment will be collected. We will identify variables independently associated with mortality and weight the variables to create 1 year and 3 year mortality prognostic indices. We will transform the 3 year prognostic index into a LE estimator. Preliminary results will be presented at the congress.

Conclusions

We will develop the first life expectancy estimator specifically for older multimorbid adults. This tool will help clinicians to tailor cardiovascular and cancer preventive care in older multimorbid adults.

Key messages

Because of the lagtime to benefit, personalizing preventive care by estimated life expectancy is recommended. We will provide the first life expectancy estimator for older multimorbid adults.

Maternal diabetes during pregnancy and carotid intima-media thickness in children

Background

Cardiovascular risk over the life course may be related to intrauterine risk factors, for instance, the exposure to maternal diabetes. Our objective was to systematically review studies that assessed the association of maternal diabetes during pregnancy and carotid-intima media thickness (CIMT), a marker of cardiovascular risk, in children.

Methods

We followed methods outlined in a published protocol for a systematic review on risk factors and determinants of CIMT in children (PROSPERO registration: CRD42017075169). Standardized mean differences in CIMT between offspring of women with and without diabetes during pregnancy were computed. Random effects meta-analyses were performed. The reliability of CIMT measurements was assessed.

Funding

SNSF 32003B-163240.

Results

Three observational studies involving 658 children were retained. Two studies were conducted in Europe and one in Australia. Age at CIMT assessment ranged from 2 days to 8 years. Two studies evaluated gestational diabetes during pregnancy and found no difference in CIMT among exposed children compared to controls (0.00 (95% CI: -0.41 to 0.41); 0.00 (95% CI; -0.28 to 0.28)). One study, that did not specify the type of diabetes evaluated, identified a higher CIMT (0.46 (95% CI; -0.07 to 1.00)). The pooled standardized mean difference in CIMT between offspring of women with and without diabetes during pregnancy was 0.08 (95% CI: -0.16 to 0.33; I2: 17.1%).

Conclusions

Overall, there is no clear association between maternal diabetes during pregnancy and offspring's CIMT. The degree of confidence in results is limited by the low number of studies, with relatively small sample sizes and a low number of participants exposed to maternal diabetes.

Key messages

Children exposed to maternal diabetes have no substantial alterations in vascular structure. More research is needed to inform primordial prevention of cardiovascular disease among these children.

Frailty to predict unplanned hospitalization, stroke, bleeding, and death in atrial fibrillation

Aims

Atrial fibrillation (AF) and frailty are common, and the prevalence is expected to rise further. We aimed to investigate the prevalence of frailty and the ability of a frailty index (FI) to predict unplanned hospitalizations, stroke, bleeding, and death in patients with AF.

Methods and results

Patients with known AF were enrolled in a prospective cohort study in Switzerland. Information on medical history, lifestyle factors, and clinical measurements were obtained. The primary outcome was unplanned hospitalization; secondary outcomes were all-cause mortality, bleeding, and stroke. The FI was measured using a cumulative deficit approach, constructed according to previously published criteria and divided into three groups (non-frail, pre-frail, and frail). The association between frailty and outcomes was assessed using multivariable-adjusted Cox regression models. Of the 2369 included patients, prevalence of pre-frailty and frailty was 60.7% and 10.6%, respectively. Pre-frailty and frailty were associated with a higher risk of unplanned hospitalizations [adjusted hazard ratio (aHR) 1.82, 95% confidence interval (CI) 1.49–2.22; P &lt; 0.001; and aHR 3.59, 95% CI 2.78–4.63, P &lt; 0.001], all-cause mortality (aHR 5.07, 95% CI 2.43–10.59; P &lt; 0.001; and aHR 16.72, 95% CI 7.75–36.05; P &lt; 0.001), and bleeding (aHR 1.53, 95% CI 1.11–2.13; P = 0.01; and aHR 2.46, 95% CI 1.61–3.77; P &lt; 0.001). Frailty, but not pre-frailty, was associated with a higher risk of stroke (aHR 3.29, 95% CI 1.2–8.39; P = 0.01).

Conclusion

Over two-thirds of patients with AF are pre-frail or frail. These patients have a high risk for unplanned hospitalizations and other adverse events. These findings emphasize the need to carefully evaluate these patients. However, whether screening for pre-frailty and frailty and targeted prevention strategies improve outcomes needs to be shown in future studies.

Clinical trial registration

Clinicaltrials.gov identifier number: NCT02105844.

Blood pressure in relation to frailty in older adults: A population-based study

In frail older adults, low blood pressure (BP) might be associated with worse health outcomes and hypertension management in this population is highly debated. Using data from a population-based study of older adults, we assessed the association between frailty and BP. We used data collected between 2014 and 2016 from 3157 participants aged between 67 and 80 years in the Lausanne cohort Lc65+. BP was measured three times at one visit, and frailty status was assessed based on Fried's phenotype model. We analyzed the cross-sectional association between BP and frailty by computing mean systolic and diastolic BP stratified by sex, age, and frailty and by fitting regression models. The average age of the participants was 73.3 (standard deviation [SD]: 4.1) years, and 59.1% were women. 34.1% were pre-frail, and 3.3% were frail. Mean BP was 135.1/76.3 mm Hg (SD 18.5/11.0). Age- and sex-adjusted systolic BP was on average lower by 2.8 mm Hg (95% confidence interval [CI]: 1.4-4.2) and 6.7 mm Hg (95% CI: 3.2-10.3) among pre-frail and frail compared to non-frail participants. Similar differences in mean diastolic BP across frailty status were found. Upon adjustment for antihypertensive treatment, the associations between frailty status and BP did not change substantially. Frail individuals had a substantially lower BP compared with non-frail older adults. Because low BP could be detrimental among frail older patients, our findings raise questions about hypertension management in this population and stress the need for additional evidence.

Screening and treatment of hypertension in older adults: less is more?

Screening and treatment of hypertension is a cornerstone of cardiovascular disease (CVD) prevention. Hypertension causes a large proportion of cases of stroke, coronary heart disease, heart failure, and associated disability and is highly prevalent especially among older adults. On the one hand, there is robust evidence that screening and treatment of hypertension prevents CVD and decreases mortality in the middle-aged population. On the other hand, among older adults, observational studies have shown either positive, negative, or no correlation between blood pressure (BP) and cardiovascular outcomes. Furthermore, there is a lack of high quality evidence for a favorable harm-benefit balance of antihypertensive treatment among older adults, especially among the oldest-old (i.e., above the age of 80 years), because very few trials have been conducted in this population. The optimal target BP may be higher among older treated hypertensive patients than among middle-aged. In addition, among frail or multimorbid older individuals, a relatively low BP may be associated with worse outcomes, and antihypertensive treatment may cause more harm than benefit. To guide hypertension screening and treatment recommendations among older patients, additional studies are needed to determine the most efficient screening strategies, to evaluate the effect of lowering BP on CVD risk and on mortality, to determine the optimal target BP, and to better understand the relationship between BP, frailty, multimorbidity, and health outcomes.

Differential reactivity of alpha- and beta-anomers of glycosyl acceptors in glycosylations. A remote consequence of the endo-anomeric effect?

When phenyl tri-O-benzyl-1-thio-beta-D-galactopyranosiduronic acid esters were coupled with a 1/1 mixture of alpha and beta 2,3 di-O-protected D-galactopyranosiduronic acid esters, the beta-anomer proved to be more reactive. Data from theoretical calculations suggested that the enhanced reactivity of this anomer compared with the alpha one would be due to a stronger hydrogen bond of the C-4 OH with the ring oxygen.

Tandem mass spectrometric analysis of aspergillus niger pectin methylesterase: mode of action on fully methyl-esterified oligogalacturonates

The substrate specificity and the mode of action of Aspergillus niger pectin methylesterase (PME) was determined using both fully methyl-esterified oligogalacturonates with degrees of polymerization (DP) 2-6 and chemically synthesized monomethyl trigalacturonates. The enzymic activity on the different substrates and a preliminary characterization of the reaction products were performed by using high-performance anion-exchange chromatography at neutral pH. Electrospray ionization tandem MS (ESI-MS/MS) was used to localize the methyl esters on the (18)O-labelled reaction products during the course of the enzymic reaction. A. niger PME is able to hydrolyse the methyl esters of fully methyl-esterified oligogalacturonates with DP 2, and preferentially hydrolyses the methyl esters located on the internal galacturonate residues, followed by hydrolysis of the methyl esters towards the reducing end. This PME is unable to hydrolyse the methyl ester of the galacturonate moiety at the non-reducing end.

Performance of selected microbial pectinases on synthetic monomethyl-esterified di- and trigalacturonates

Two monomethyl esters of alpha-(1-4)-linked D-galacturonic dimers and three monomethyl esters of alpha-(1-4)-linked D-galacturonic acid trimers were synthesized chemically and further used as substrates in order to establish the substrate specificity of six different endopolygalacturonases from Aspergillus niger, one exopolygalacturonase from Aspergillus tubingensis, and four selected Erwinia chrysanthemi pectinases; exopolygalacturonan hydrolase X (PehX), exopolygalacturonate lyase X (PelX), exopectate lyase W (PelW), and oligogalacturonan lyase (Ogl). All A. niger endopolygalacturonases (PGs) were unable to hydrolyze the two monomethyldigalacturonates and 2-methyltrigalacturonate, whereas 1-methyltrigalacturonate was only cleaved by PGI, PGII, and PGB albeit at an extremely low rate. The hydrolysis of 3-methyltrigalacturonate into 2-methyldigalacturonate and galacturonate by all endopolygalacturonases demonstrates that these enzymes can accommodate a methylgalacturonate at subsite -2. The A. tubingensis exopolygalacturonase hydrolyzed the monomethyl-esterified digalacturonates and trigalacturonates although at lower rates than for the corresponding oligogalacturonates. 1-Methyltrigalacturonate was hydrolyzed at the same rate as trigalacturonate which demonstrates that the presence of a methyl ester at the third galacturonic acid from the nonreducing end does not have any effect on the performance of exopolygalacturonase. Of the four E. chrysanthemi pectinases, Ogl was the only enzyme able to cleave digalacturonate, whereas all four enzymes cleaved trigalacturonate. Ogl does not cleave monomethyl-esterified digalacturonate and trigalacturonate in case the second galacturonic acid residue from the reducing end is methyl-esterified. PehX did not hydrolyze any of the monomethyl-esterified trigalacturonates. The two lyases, PelX and PelW, were both only able to cleave 1-methyltrigalacturonate into Delta4,5-unsaturated 1-methyldigalacturonate and galacturonate.

Synthesis of the two monomethyl esters of the disaccharide 4-O-alpha-D-galacturonosyl-D-galacturonic acid and of precursors for the preparation of higher oligomers methyl uronated in definite sequences

Methyl (alpha-D-galactopyranosyluronic acid)-(1-->4)-D-galactopyranuronate and methyl alpha-D-galactopyranosyl-uronate-(1-->4)-D-galactopyranuronic acid have been synthesized by coupling methyl (benzyl 2,3-di-O-benzyl-beta-D-galactopyranosid)uronate (3) or benzyl (benzyl 2,3-di-O-benzyl-beta-D-galactopyranosid)uronate (4) with benzyl (phenyl 2,3,4-tri-O-benzyl-1-thio-beta-D-galactopyranosid)uronate and methyl (phenyl 2,3,4-tri-O-benzyl-1-thio-beta-D-galactopyranosid)uronate, respectively, using N-iodosuccinimide and trifluoromethanesulphonic acid as promoters, followed by removal of the benzyl groups. The 4'-OH unprotected dimers benzyl (methyl 2,3-di-O-benzyl-alpha-D-galactopyranosyluronate)-(1-->4)-(benzyl 2,3-di-O-benzyl-beta-D-galactopyranosid)uronate and methyl (benzyl 2,3-di-O-benzyl-alpha-D-galactopyranosyluronate)-(1-->4)-(benzyl 2,3-di-O-benzyl-beta-D-galactopyranosid)uronate were prepared from methyl (phenyl 2,3-di-O-benzyl-1-thio-4-O-trimethylsilyl-beta-D-galactopyranosid) uronate and benzyl (phenyl 2,3-di-O-benzyl-1-thio-4-O-trimethylsilyl-beta-D-galactopyranosid) uronate and acceptors 4 or 3, respectively. These compounds have been designed to serve as precursors for the preparation of higher-membered D-galacturonic acid oligomers methyl esterified in definite positions.

Inducing properties of analogs of 2-keto-3-deoxygluconate on the expression of pectinase genes of Erwinia chrysanthemi

In Erwinia chrysanthemi, all the genes involved in pectin degradation are controlled by the negative regulatory gene kdgR. 2-keto-3-deoxy-gluconate (KDG) is the inducing molecule that interacts with KdgR to allow the expression of all the genes of the kdg regulon. The inducing properties on the expression of genes regulated by kdgR of various analogs and derivatives of KDG were tested. All the inducers share the common moiety COOH-CO-CH2-CHOH-C-C included in a pyranic cycle. Our results show that esterification of C1 prevents induction. Presence of a ketone function on C2 and absence of hydroxyl on C3 are necessary for induction. The nature and the configuration of substituent on C5 has no influence on induction. Two compounds have interesting properties: 5-O-methyl-KDG is a gratuitous inducer, and gluconic acid can prevent induction.

Conception and realization of artificial dyed embryos for training in in vitro fertilization and embryo transfer (IVF and ET)

An artificial embryo model is proposed for current training in in vitro fertilization and embryo transfer. It consists in resin microballs of 180 micron diameter, stained either with fluoresceinamin or methylene blue. These microspheres release, even at the maximum dye concentrations tested, very negligible amounts of dye; heat stable they can be sterilized. This model, already checked for human embryo transfer, seems to be a useful tool in other reproduction studies such as embryo transport.

Bile acid sulfates in serum bile acids determination

Some bile acid sulfates were synthesized and characterized. The configuration of sulfate groups at C-3, C-7 and C-12 positions was confirmed by Nuclear Magnetic Resonance analysis. These sulfates were utilized in a study of their chemical behaviour in different analytical procedures currently used for serum bile acids determination. Procedures for bile acids extraction from serum with ethanol or Amberlite XAD-2 result in an important loss of the most polar sulfated bile acids. Complete separation of unsulfated from sulfated bile acids on Sephadex LH-20 is not achieved when deconjugation of the most polar bile acid sulfate is slow but does not produce artifacts. Enzymatic determination of bile acids gives positive response with some bile acid sulfates. The current procedures of serum bile acids determination are discussed in consideration of these results.