This review highlights the lack of consensus regarding a definition of cognitive reserve. Further research is required to clarify how the indicators already identified may provide cognitive reserve and offer a protective effect against dementia. Agreement on the indicators that constitute the cognitive reserve model is needed before testing possible interventions that may increase the reserve supply and improve cognition.

SUMMARYBackground: Insulin resistance and oxidative stress induced by products of small intestinal bacterial activity are putative factors in the pathogenesis of non-alcoholic steatohepatitis. Acylated ghrelin is the biologically active form of an orexigenic gastric hormone that modifies insulin sensitivity and body composition. Aim: To investigate the effect of ciprofloxacin on small intestinal bacterial activity, ethanol, ghrelin and insulin in non-alcoholic steatohepatitis patients. Methods: Twelve non-alcoholic steatohepatitis patients and 11 controls were studied before and after ciprofloxacin 500 mg b.d. for 5 days. After an overnight fast, 75 g glucose was ingested and blood was sampled every 20 min for 120 min. Acylated and total ghrelin, ethanol and insulin were measured. Small intestinal bacterial activity was detected by glucose hydrogen breath test. Results: Mean (range) integrated plasma acylated ghrelin which was 102 (21-241) and 202 (88-366) pg/ mL AE 2 h in non-alcoholic steatohepatitis and controls

Available literature suggests that both vitamin D and calcium may be associated with a wide range of non-skeletal outcomes. However, epidemiological evidence supporting their individual associations with incident cerebrovascular disease is scarce. We conducted a systematic review and meta-analysis of prospective cohort studies, published before February 2012 and sought from MEDLINE, EMBASE, BIOSIS and the Science Citation Index databases, and reported cerebrovascular disease (defined as any fatal or non-fatal ischemic stroke, hemorrhagic stroke, cerebrovascular accident or transient ischemic attack) by circulating vitamin D (25-hydroxy vitamin D [25(OH)D] as active metabolite) and calcium levels. Two independent investigators abstracted information on 25(OH)D and calcium, cerebrovascular outcomes and other characteristics from selected studies. Relative risks (RRs) were pooled by both random and fixed effects meta-analyses and were further examined under different study-level characteristics. Publication bias was assessed with funnel plots and Egger's asymmetry test. From 5,778 initial references, nine unique prospective cohort studies met our inclusion criteria. Seven studies (involving 47,809 participants and 926 cerebrovascular events) focused on circulating 25(OH)D and 3 reported on circulating calcium (22,577 participants and 727 events). For 25(OH)D, in a comparison of individuals in the top third versus those in the bottom third at baseline, the combined RR for cerebrovascular disease, adjusted for several conventional risk factors, was 0.60 (95 % CI 0.48, 0.72). The corresponding RR in the prospective studies that reported on baseline circulating calcium levels for cerebrovascular disease was 1.40 (95 % CI 1.19, 1.64). There was no apparent evidence of heterogeneity or publication bias among included studies. Available data indicate that higher circulating level of vitamin D is associated with a decreased risk of cerebrovascular disease. Conversely, higher circulating calcium concentration is associated with an increased risk of cerebrovascular disease.

Abstract Background On the first haemodialysis (HD) day after the 2-day break in three times a week (3×W) in-centre HD, mortality and hospitalization are higher. If longer HD sessions prescribed 3×W is associated with a reduction in these events is unknown. Methods HD session length in 19 557 prevalent European in-centre 3×W HD patients participating in the Dialysis Outcomes and Practice Patterns Study (1998–2011) were categorized into <200, 200–225, 226–250 or >250 min. Standardized event rates on the first (HD1) versus the second (HD2) HD day after the 2-day break, with supporting Cox proportional hazards models adjusted for patient and dialysis characteristics, were generated for all-cause mortality, all-cause hospitalization, out-of-hospital death and fluid overload hospitalization. Results By comparing HD1 with HD2, increased rates of all endpoints were observed (all P < 0.002). As HD session lengthened across the four groups, all-cause mortality per 100 patient-years on the HD1 (23.0, 20.4, 16.4 and 14.6) and HD2 (26.1, 13.3, 13.4 and 12.1) reduced. Similar improvements were observed for out-of-hospital death but were less marked for hospitalization endpoints. However, even patients dialysing >250 min were at significantly greater risk on HD1 when compared with their HD2 for out-of-hospital death [hazard ratio (HR) = 2.1, 95% CI 1.0–4.3], all-cause hospitalization (HR = 1.3, 95% CI 1.2–1.4) and fluid overload hospitalization (HR = 3.2, 95% CI 1.8–6.0). Conclusions Despite the association between reduced mortality across all dialysis days in patients performing longer sessions, elevated risk on the first dialysis day relative to the second persists even in patients dialysing 4.5 h 3×W.

Background and Objective The COVID-19 pandemic and the measures taken by governments to contain it have affected many aspects of the daily lives of citizens. This study aimed to describe changes in the productivity of paid work and time allocation to paid and unpaid work and leisure resulting from working at home during the pandemic. Methods A sample of 851 people from the Netherlands who had paid work (≥ 24 h/week) and worked at least 4 hours per week extra at home because of lockdown measures completed a questionnaire during the first COVID-19 lockdown (April 2020). Respondents reported time spent on paid and unpaid work and leisure before and during the lockdown. Productivity was measured in terms of quantity and quality of paid work. Results On average, respondents spent less time (14%) on paid work and productivity decreased 5.5%. Changes in productivity were associated with the age of children, net income and having a separate home office. Respondents spent more time on unpaid work (27%) and leisure (11%). Women spent more time on unpaid work in absolute but not in relative terms. People with a partner and with children spent more time on unpaid work and less time on leisure. Conclusions Productivity of paid work decreased, and people reallocated time between paid and unpaid work and leisure during the first COVID-19 lockdown. Changes in time allocation and productivity differed across subgroups. If working at home becomes more common, future research should focus on the long-term impact on productivity and mental and physical health.

Systematic evaluation of all available primary surveillance studies, particularly in the context of WHO STEPS guidelines, indicates inadequate adherence to standardized surveillance methodology in LMI countries. Incorporation of standardized approaches is essential to enhance generalizability and estimate stroke burden accurately in these resource-poor settings.

Background High blood pressure levels and higher arterial stiffness have been shown to be associated with lower cognition during adulthood, possibly by accumulative changes over time. However, vascular factors may already affect the brain during early life. Methods and Results We examined the relation between cognition and vascular factors within 5853 children from the Generation R Study (mean age 6.2 years) and 5187 adults from the Rotterdam Study (mean age 61.8 years). Diastolic and systolic blood pressure and arterial stiffness were assessed, the latter by measuring pulse‐wave velocity and pulse pressure. For cognition, the Generation R Study relied on nonverbal intelligence, whereas the Rotterdam Study relied on a cognitive test battery to calculate the g‐factor, a measure of global cognition. In the Generation R Study, standardized diastolic blood pressure showed a significant association with standardized nonverbal intelligence (β=−0.030, 95% confidence interval=[−0.054; −0.005]) after full adjustment. This association held up after excluding the top diastolic blood pressure decile (β=−0.042 [−0.075; −0.009]), suggesting that the relation holds in normotensives. Within the Rotterdam Study, standardized cognition associated linearly with standardized systolic blood pressure (β=−0.036 [−0.060; −0.012]), standardized pulse‐wave velocity (β=−0.064 [−0.095; −0.033]), and standardized pulse pressure (β=−0.044 [−0.069; −0.020], and nonlinearly with standardized diastolic blood pressure (quadratic term β=−0.032 [−0.049; −0.015]) after full adjustment. Conclusions Blood pressure and cognition may already be related in the general population during early childhood, albeit differently than during adulthood.

BackgroundAccumulating evidence suggests that breastfeeding benefits children’s intelligence, possibly due to long-chain polyunsaturated fatty acids (LC-PUFAs) present in breast milk. Under a nutritional adequacy hypothesis, an interaction between breastfeeding and genetic variants associated with endogenous LC-PUFAs synthesis might be expected. However, the literature on this topic is controversial.MethodsWe investigated this gene × environment interaction through a collaborative effort. The primary analysis involved >12 000 individuals and used ever breastfeeding, FADS2 polymorphisms rs174575 and rs1535 coded assuming a recessive effect of the G allele, and intelligence quotient (IQ) in Z scores.ResultsThere was no strong evidence of interaction, with pooled covariate-adjusted interaction coefficients (i.e. difference between genetic groups of the difference in IQ Z scores comparing ever with never breastfed individuals) of 0.12[(95% confidence interval (CI): −0.19; 0.43] and 0.06 (95% CI: −0.16; 0.27) for the rs174575 and rs1535 variants, respectively. Secondary analyses corroborated these results. In studies with ≥5.85 and <5.85 months of breastfeeding duration, pooled estimates for the rs174575 variant were 0.50 (95% CI: −0.06; 1.06) and 0.14 (95% CI: −0.10; 0.38), respectively, and 0.27 (95% CI: −0.28; 0.82) and −0.01 (95% CI: −0.19; 0.16) for the rs1535 variant.ConclusionsOur findings did not support an interaction between ever breastfeeding and FADS2 polymorphisms. However, subgroup analysis suggested that breastfeeding may supply LC-PUFAs requirements for cognitive development if breastfeeding lasts for some (currently unknown) time. Future studies in large individual-level datasets would allow properly powered subgroup analyses and further improve our understanding on the breastfeeding × FADS2 interaction.