Associations of individual chronic diseases and multimorbidity with multidimensional frailty.

OBJECTIVE: To examine the associations between individual chronic diseases and multidimensional frailty comprising physical, psychological, and social frailty. METHODS: Dutch individuals (N = 47,768) age ≥ 65 years completed a general health questionnaire sent by the Public Health Services (response rate of 58.5 %), including data concerning self-reported chronic diseases, multidimensional frailty, and sociodemographic characteristics. Multidimensional frailty was assessed with the Tilburg Frailty Indicator (TFI). Total frailty and each frailty domain were regressed onto background characteristics and the six most prevalent chronic diseases: diabetes mellitus, cancer, hypertension, arthrosis, urinary incontinence, and severe back disorder. Multimorbidity was defined as the presence of combinations of these six diseases. RESULTS: The six chronic diseases had medium and strong associations with total ((f2 = 0.122) and physical frailty (f2 = 0.170), respectively, and weak associations with psychological (f2 = 0.023) and social frailty (f2 = 0.008). The effects of the six diseases on the frailty variables differed strongly across diseases, with urinary incontinence and severe back disorder impairing frailty most. No synergetic effects were found; the effects of a disease on frailty did not get noteworthy stronger in the presence of another disease. CONCLUSIONS: Chronic diseases, in particular urinary incontinence and severe back disorder, were associated with frailty. We thus recommend assigning different weights to individual chronic diseases in a measure of multimorbidity that aims to examine effects of multimorbidity on multidimensional frailty. Because there were no synergetic effects of chronic diseases, the measure does not need to include interactions between diseases.

SARS-CoV-2 antibodies persist up to 12 months after natural infection in healthy employees working in non-medical contact-intensive professions.

OBJECTIVES: This study aimed to evaluate dynamics of antibody levels after exposure to SARS-CoV-2 for 12 months in Dutch non-vaccinated hairdressers and hospitality staff. METHODS: In this prospective cohort study, blood samples were collected every 3 months for 1 year and analyzed using a qualitative total antibody enzyme-linked immunosorbent assay (ELISA) and a quantitative immunoglobulin (Ig)G antibody ELISA. Participants completed questionnaires, providing information on demographics, health, and work. Differences in antibody levels were evaluated using Mann-Whitney U and Wilcoxon signed-rank tests. Beta coefficients (ß) and 95% confidence intervals (CIs) were calculated using linear regression. RESULTS: Ninety-five of 497 participants (19.1%) had ≥1 seropositive measurement before their last visit using the qualitative ELISA. Only 2.1% (2/95) seroreverted during follow-up. Of 95 participants, 82 (86.3%) tested IgG seropositive in the quantitative ELISA too. IgG antibody levels significantly decreased in the first months (P <0.01) but remained detectable for up to 12 months in all participants. Older age (ß, 10-years increment: 24.6, 95% CI: 5.7-43.5) and higher body mass index (ß, 5kg/m² increment: 40.0, 95% CI: 2.9-77.2) were significantly associated with a higher peak of antibody levels. CONCLUSION: In this cohort, SARS-CoV-2 antibodies persisted for up to 1 year after initial seropositivity, suggesting long-term natural immunity.

Structuring and validating a cost-effectiveness model of primary asthma prevention amongst children.

BACKGROUND: Given the rising number of asthma cases and the increasing costs of health care, prevention may be the best cure. Decisions regarding the implementation of prevention programmes in general and choosing between unifaceted and multifaceted strategies in particular are urgently needed. Existing trials on the primary prevention of asthma are, however, insufficient on their own to inform the decision of stakeholders regarding the cost-effectiveness of such prevention strategies. Decision analytic modelling synthesises available data for the cost-effectiveness evaluation of strategies in an explicit manner. Published reports on model development should provide the detail and transparency required to increase the acceptability of cost-effectiveness modelling. But, detail on the explicit steps and the involvement of experts in structuring a model is often unevenly reported. In this paper, we describe a procedure to structure and validate a model for the primary prevention of asthma in children. METHODS: An expert panel was convened for round-table discussions to frame the cost-effectiveness research question and to select and structure a model. The model's structural validity, which indicates how well a model reflects the reality, was determined through descriptive and parallel validation. Descriptive validation was performed with the experts. Parallel validation qualitatively compared similarity between other published models with different decision problems. RESULTS: The multidisciplinary input of experts helped to develop a decision-tree structure which compares the current situation with screening and prevention. The prevention was further divided between multifaceted and unifaceted approaches to analyse the differences. The clinical outcome was diagnosis of asthma. No similar model was found in the literature discussing the same decision problem. Structural validity in terms of descriptive validity was achieved with the experts and was supported by parallel validation. CONCLUSIONS: A decision-tree model developed with experts in round-table discussions benefits from a systematic and transparent approach and the multidisciplinary contributions of the experts. Parallel validation provides a feasible alternative to validating novel models. The process of structuring and validating a model presented in this paper could be a useful guide to increase transparency, credibility, and acceptability of (future, novel) models when experts are involved.

SARS-CoV-2 antibodies in employees working in non-medical contact-intensive professions in the Netherlands: Baseline data from the prospective COco-study.

COVID-19 has made a global impact since early 2020, requiring characterization of the SARS-CoV-2 virus, including transmission risk. The COco-study aims to evaluate the risk for COVID-19 infections in two non-medical contact-intensive professions. COco is a prospective cohort study evaluating SARS-CoV-2 antibodies in hairdressers and hospitality personnel in the province of North-Brabant in the Netherlands, using a total antibody enzyme-linked immunosorbent assay. Baseline data from June/July 2020 were analyzed. Participants filled out a questionnaire, providing information on demographics, health, work situation, and risk factors for COVID-19. Odds ratios (OR) and 95% confidence intervals (95% CI) were calculated using logistic regression. In June/July 2020, 497 participants were enrolled: 236 hairdressers, 259 hospitality employees, and two participants worked in both industries. Hospitality staff was more frequently seropositive than hairdressers (14.2% versus 8.0%, respectively; OR 1.9, 95% CI 1.1-3.4). Furthermore, a high education level (OR 3.0, 95% CI: 1.7-5.6) and increased alcohol use (OR, 7 glasses per week increment: 1.3, 95% CI: 1.1-1.5) were associated with seropositivity. Of the 56 seropositive participants, 18 (32%) had not experienced any COVID-19 symptoms. The symptoms anosmia/ageusia differed most evidently between seropositive and seronegative participants (53.6% versus 5.7%, respectively; P < 0.001 (chi-squared test)). In conclusion, four months after the first identified COVID-19 patient in the Netherlands, employees in the hospitality industry had significantly more frequently detectable SARS-CoV-2 antibodies than hairdressers.

Cost-effectiveness of primary prevention of paediatric asthma: a decision-analytic model.

BACKGROUND: Many children stand to benefit from being asthma-free for life with primary (i.e., prenatally started) prevention addressing one environmental exposure in a unifaceted (UF) approach or at least two in a multifaceted (MF) approach. We assessed the cost-effectiveness of primary prevention programmes for Dutch children in a decision-analytic framework. METHODS: A decision-analytic tree model analysing healthcare costs and asthma cases prevented was developed to compare usual care (UC) with two UF and three MF programmes on the primary prevention of asthma amongst children. Programmes were evaluated through incremental cost-effectiveness ratios and net monetary benefits. Decision and parameter uncertainty were subjected to value-of-information analyses. RESULTS: The current UC and one of three MF programmes dominated the other alternatives. The MF programme was more costly but also more effective than UC at an incremental cost-effectiveness ratio of 8,209.20/additional asthma case prevented. The value of perfect information to reduce uncertainty was 291.6M at its lowest. Most of the uncertainty in the cost-effectiveness threshold was attributable to the probability and cost estimates for low-risk children. CONCLUSION: This study supports the feasibility of a structured programme that simultaneously addresses exposure to house dust mites, pet dander, environmental tobacco, and breast-feeding as a cost-effective alternative to UC in the primary prevention of asthma amongst children.

Interactive effect of family history and environmental factors on respiratory tract-related morbidity in infancy.

BACKGROUND: Family and environmental factors affect the development of respiratory morbidity. How these factors interact is unclear. OBJECTIVE: We sought to clarify the interactive effect of family history of asthma and environmental factors on the occurrence of respiratory morbidity. METHODS: Two hundred twenty-one infants with a positive family history of asthma (PFH) and 308 with a negative family history of asthma (NFH) were prenatally selected and followed until the age of 2 years. Exposure to environmental factors and the occurrence of respiratory morbidity were recorded. By using multiple logistic regression analysis, increased risk was expressed in odds ratios (ORs) adjusted for relevant covariables. RESULTS: Infants with a PFH had more respiratory morbidity than infants with an NFH. Adjusted ORs ranged from 1.7 (95% CI, 1.0-2.8) for expiratory wheezing to 4.9 (95% CI, 1.7-13.6) for croup. Parental smoking increased the OR of a PFH for wheezing ever (OR, 5.8 [95% CI, 2.5-13.8]) and attacks of wheezing (OR, 6.8 [95% CI, 2.7-16.9]), as did Der p 1 (OR, 10.2 [95% CI, 2.8-36.3] and OR, 7.1 [95% CI, 7.1-21.0], respectively). Exposure to both parental smoking and Der p 1 further increased this OR (OR, 30.8 [95%, CI, 6.9-137.2] and OR, 26.2 [95% CI, 5.9-115.6], respectively). Breast-feeding decreased the ORs of PFH for tonsillitis and acute otitis media: the increased ORs for these diagnoses in formula-fed infants with PFHs versus those with NFHs (OR, 9.2 [95% CI, 2.1-39.7] and OR, 2.9 [95% CI, 1.1-7.2], respectively) was attenuated in breast-fed infants (OR, 1.8 [95% CI, 0.8-3.8] and OR, 0.7 [95% CI, 0.4-1.3]). CONCLUSION: Parental smoking and Der p 1 increase the effect of a PFH on respiratory morbidity. Breast-feeding reduces this effect. CLINICAL IMPLICATIONS: Extra attention should be given to stimulate mothers to breast-feed their children in case they cannot stop smoking or taking sanitation measures.

The primary prevention of asthma in children study: design of a multifaceted prevention program.

The PREVASC study addresses the primary prevention of asthma in infants and small children. The objective of this study is to investigate whether a multifaceted prenatally started intervention strategy in high-risk infants leads to a decrease in the occurrence of (severe) asthma and whether a refinement of the prevention strategy leads to an increase in the adherence to the prevention program. The primary prevention program includes house dust mite impermeable bed coverings, education on breast feeding, hypoallergenic feeding, timing of introduction of solid food and smoking cessation. A total of 888 infants were prenatally included. By the time of inclusion the mothers were 3-7 months pregnant. About 27 infants were excluded from the study and 18 dropped out. Of the remaining 843 infants 535 had a first-degree familial predisposition of asthma (high-risk group), whereas a reference group of 308 (162 boys) infants was not predisposed for asthma in the first-degree (low-risk group). To evaluate the (cost-)effectiveness of the preventive intervention, 222 (118 boys) infants of the high-risk group allocated to the intervention group and 221 (112 boys) allocated to a control group are followed up. The low-risk infants served as controls to evaluate the predictive value of high risk (first-degree familial predisposition of asthma). The infants are followed from the prenatal stage until they reach the age of 6 yr. The remaining 92 high-risk infants were included in an optimized randomized-clinical adherence trial (RCAT). Of these 92 infants, 45 (20 boys) were allocated to an intervention group and 47 (24 boys) to a control group. Until now all infants have been followed for at least 1 yr.

Rentabilidad de la prevención primaria del asma en lactantes de alto riesgo: 0-2 años / Cost-effectiveness of primary prevention of asthma in high-risk infants: 0-2 years

Con el fin de investigar la rentabilidad de la prevención primaria del asma en lactantes de alto riesgo, de hasta 2 años, desde la perspectiva de la sociedad (PREVASC) y con un diagnóstico clínico de asma realizado por un médico generalista (MG) y un diagnóstico epidemiológico de asma basado en un modelo de predicción (EPM), se seleccionaron 476 lactantes de un ensayo aleatorizado y controlado (242 en el grupo de intervención, 234 en el grupo control). Por medio de informes semanales se evaluó la utilización de los recursos de salud. El margen de error acerca de los índices de rentabilidad incremental se determinó por análisis bootstrap. El 26.8% de los niños del grupo de intervención y el 25.5% de los controles recibieron el diagnóstico de asma por parte de un MG, mientras que el 69.9% y el 63.5%, respectivamente, tuvo el diagnóstico basado en un EPM. Con ambas definiciones no hubo diferencias en el diagnóstico de asma entre los participantes del grupo de intervención y el grupo control (odds ratio [OR]: 1.1, intervalo de confianza del 95% [IC]: 0.6-1.8 y OR: 1.3, IC: 0.8-2.2). La media de los costos totales en el grupo de intervención y el grupo control fue de 1564 euros (rango intercuartiles: 669-6 499 euros) y de 967 euros (rango intercuartiles: 29-7 136 euros). El índice de rentabilidad incremental del programa fue de -46 157 euros para el diagnóstico de asma por un MG y de -9 671 euros para la definición EPM, lo cual señala la inferioridad de la situación experimental. Todas las replicaciones bootstrap indicaron que el programa PREVASC es más costoso, con una probabilidad del 37% y del 13%, respectivamente, de que éste fuese más eficaz que la atención usual. La prevención primaria del asma en los primeros 2 años de vida no fue rentable con ambos modelos.