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Abstract: Objectives: In randomized controlled trials with many potential prognostic factors, serious imbalance among treatment groups regarding these factors can occur. Minimization methods can improve balance but increase the possibility of selection bias. We described and evaluated the performance of a new method of treatment allocation, called studywise minimization, that can avoid imbalance by chance and reduce selection bias. Study Design and Setting: The studywise minimization algorithm consists of three steps: (1) calculate the imbalance for all possible allocations, (2) list all allocations with minimum imbalance, and (3) randomly select one of the allocations with minimum imbalance. We carried out a simulation study to compare the performance of studywise minimization with three other allocation methods: randomization, biased-coin minimization, and deterministic minimization. Performance was measured, calculating maximal and average imbalance as a percentage of the group size. Results: Independent of trial size and number of prognostic factors, the risk of serious imbalance was the highest in randomization and absent in studywise minimization. The largest differences among the allocation methods regarding the risk of imbalance were found in small trials. Conclusion: Studywise minimization is particularly useful in small trials, where it eliminates the risk of serious imbalances without generating the occurrence of selection bias. [ABSTRACT FROM AUTHOR]

Dementia is a clinical diagnosis without curative treatment. It is uncertain whether ancillary testing is beneficial for patients. This study investigates the association between use of diagnostic tests and time to poor outcome and health care costs. Nationwide register-based cohort study using health care reimbursement data in the Netherlands. All Dutch hospitals, including 13,312 patients diagnosed with dementia in 2018. Diagnostic testing included computed tomography or magnetic resonance imaging (CT/MRI), neuropsychological examination (NPE), nuclear imaging (PET/SPECT), electroencephalography (EEG), and cerebrospinal fluid (CSF) testing. We compared time to poor outcome (institutionalization or death) and costs per month from 2018 to 2021 between those who underwent a specific diagnostic test in previous years to controls, propensity score matched for age, sex, type of hospital, and comorbidity. Time to poor outcome in those who underwent CT/MRI, EEG, or CSF testing was similar to those who did not, but was longer for those who underwent NPE. Time to poor outcome was shorter in patients who underwent PET/SPECT. Patients who underwent CSF testing or PET/SPECT had higher mean total health care costs as compared to controls (CSF €248, 95% CI 64-433; PET/SPECT: €315, 95% CI 179-451). NPE during the diagnostic trajectory was associated with lower total health care cost (–€127, 95% CI –62, –193). NPE was associated with longer time to poor outcome and lower health care costs, potentially due to confounding by indication. Patients who underwent neuroimaging (CT, MRI, SPECT/PET), CSF testing, or EEG for dementia diagnostics did not experience a longer time to poor outcome or lower health care costs. This emphasizes the importance of clinical examination as anchor for the diagnosis of dementia. [ABSTRACT FROM AUTHOR]

Abstract: Objective: In some trials, the intervention is delivered to individuals in groups, for example, groups that exercise together. The group structure of such trials has to be taken into consideration in the analysis and has an impact on the power of the trial. Our aim was to provide optimal methods for the design and analysis of such trials. Study Design and Setting: We described various treatment allocation methods and presented a new allocation algorithm: optimal batchwise minimization (OBM). We carried out a simulation study to evaluate the performance of unrestricted randomization, stratification, permuted block randomization, deterministic minimization, and OBM. Furthermore, we described appropriate analysis methods and derived a formula to calculate the study size. Results: Stratification, deterministic minimization, and OBM had considerably less risk of imbalance than unrestricted randomization and permuted block randomization. Furthermore, OBM led to unpredictable treatment allocation. The sample size calculation and the analysis of the study must be based on a multilevel model that takes the group structure of the trial into account. Conclusion: Trials evaluating interventions that are carried out in subsequent groups require adapted treatment allocation, power calculation, and analysis methods. From the perspective of obtaining overall balance, we conclude that minimization is the method of choice. When the number of prognostic factors is low, stratification is an excellent alternative. OBM leads to better balance within the batches, but it is more complicated. It is probably most worthwhile in trials with many prognostic factors. From the perspective of predictability, a treatment allocation method, such as OBM, that allocates several subjects at the same time, is superior to other methods because it leads to the lowest possible predictability. [Copyright &y& Elsevier]

Dysregulation of the negative feedback loop of the hypothalamic-pituitary-adrenal (HPA) axis may have damaging effects on the brain, potentially under influence of psychosocial health factors. We studied associations between functioning of the negative feedback loop of HPA-axis, measured with a very low-dose dexamethasone suppression test (DST), and brain structure in middle-aged and older adults, and whether these associations were modified by psychosocial health. From 2006 to 2008, 1259 participants (mean age 57.6 ± 6.4, 59.6 % female) of the population-based Rotterdam Study completed a very low-dose DST (0.25 mg) and underwent magnetic resonance imaging (MRI) of the brain. Self-reported psychosocial health (depressive symptoms, loneliness, marital status, perceived social support) were assessed in the same time period. Multivariable linear and logistic regression were used to study cross-sectional associations between cortisol response and brain volumetrics, cerebral small vessel disease markers and white matter structural integrity. To assess the effect of psychosocial health on these associations, analyses were further stratified for psychosocial health markers. Cortisol response was not associated with markers of global brain structure in the overall study sample. However, in participants with clinically relevant depressive symptoms, a diminished cortisol response was associated with smaller white matter volume (mean difference: − 1.00 mL, 95 %CI = − 1.89;− 0.10) and smaller white matter hyperintensity volume (mean difference: − 0.03 mL (log), 95 %CI = − 0.05;0.00). In participants with low/moderate perceived social support compared to those with high social support, a diminished cortisol response was associated with larger gray matter volume (mean difference: 0.70 mL, 95 %CI = 0.01;1.39) and higher fractional anisotropy (standardized mean difference 0.03, 95 %CI = 0.00;0.06). Diminished function of the HPA-axis is differently associated with brain structure in community-dwelling middle-aged and older adults with clinically relevant depressive symptoms or suboptimal social support, but not in adults without depressive symptoms or with optimal social support. • Cortisol response after a DST is not associated with global brain structure. • In depression, diminished cortisol response associated with worse brain structure. • With low social support, reduced cortisol response is linked to better brain health. [ABSTRACT FROM AUTHOR]

The complex care needs of frail older persons living at home is a major challenge for health care systems worldwide. One possible solution is to employ a primary care physician (PCP) with additional geriatric expertise. In the Netherlands, elderly care physicians (ECPs), who traditionally work in nursing homes, are increasingly encouraged to utilize their expertise within primary care. However, little is known about how PCPs and ECPs collaborate. Therefore, we aimed to unravel the nature of the current PCP-ECP collaboration in primary care for frail older persons, and to identify key concepts for success. A qualitative multiple case study with semistructured interviews. A selection of 22 participants from 7 "established collaboration practices" within the primary care setting in the Netherlands, including at least 1 ECP, 1 PCP, and 1 other health care professional for every included established collaboration practice. Transcripts of individual interviews were analyzed using largely double and independent open and axial coding, and formulation of themes and subthemes. Data analysis revealed 4 key concepts for success: (1) clarification of roles and expectations (ie, patient-centered care and embedding in existing care networks), (2) trust, respect, and familiarity as drivers for collaboration (ie, mutual trust through knowing each other and having shared goals); (3) framework for regular communication (ie, structural meetings and a shared vision); and (4) government, payer, and organization support (ie, financial support and emphasis on the collaboration's urgency by organizations and national policy makers). For a successful generalist-specialist collaboration, health care professionals need to invest in building relationships and mutual trust, and incorporating their efforts in the existing care networks to guarantee patient-centeredness. When provided with reimbursement and appreciation, this collaboration is a promising change in general practice to improve the care and outcomes of frail older persons. [ABSTRACT FROM AUTHOR]

Advance care planning (ACP) is seldom initiated with people with dementia (PWD) and mainly focuses on medical end-of-life decisions. We studied the effects of an educational intervention for general practitioners (GPs) aimed at initiating and optimizing ACP, with a focus on discussing medical and nonmedical preferences of future care. A single-blinded cluster randomized controlled trial. In 2016, 38 Dutch GPs (all from different practices) completed the study. They recruited 140 PWD, aged ≥65 years at any stage and with any type of dementia, from their practice. Intervention group GPs were trained in ACP, including shared decision-making and role-playing exercises. Control group GPs provided usual care. The primary outcome was ACP initiation: the proportion of PWD that had at least 1 ACP conversation documented in their medical file. Key secondary outcomes were the number of medical (ie, resuscitation, hospital admission) and nonmedical (ie, activities, social contacts) preferences discussed. At the 6-month follow-up, subjects' medical records were analyzed using random effect logistics and linear models with correction for GP clustering. 38 GP clusters (19 intervention; 19 control) included 140 PWD (intervention 73; control 67). Four PWD (2.9%) dropped out on the primary and key secondary outcomes. After 6 months, intervention group GPs initiated ACP with 35 PWD (49.3%), and control group GPs initiated ACP with 9 PWD (13.9%) [odds ratio (OR) 1.99; P =.002]. Intervention group GPs discussed 0.8 more medical [95% confidence interval (CI) 0.3, 1.3; P =.003] and 1.5 more nonmedical (95% CI 0.8, 2.3; P <.001) preferences per person with dementia than control group GPs. Our educational intervention increased ACP initiation, and the number of nonmedical and medical preferences discussed. This intervention has the potential to better align future care of PWD with their preferences but because of the short follow-up, the GPs' long-term adoption remains unknown. [ABSTRACT FROM AUTHOR]