A cross-sectional study on stool- and gastrointestinal-related outcomes of Mexican infants consuming different formulae

BACKGROUND

Immaturities present at birth, such as in the gut microbiome and digestive, nervous, and immune system, resolve with time. Nevertheless, this may result in mild digestive symptoms early in life, particularly in formula-fed infants. Formula composition and processing may impact this discomfort. This study therefore aimed to assess stool characteristics and gastrointestinal symptoms of healthy infants fed different formulae.

METHODS

A multicenter, cross-sectional, observational trial was performed in Mexico between November 2019 and January 2022, where exclusively formula-fed infants (n = 342, aged 1-4 months) were studied in four groups based on their existing formula use. Feeding was continued per practice following label instructions. For 7 days, parents/caregivers were requested to record fecal characteristics, using the Amsterdam Infant Stool Scale, and rate gastrointestinal symptoms. Stool samples were collected to determine pH, dry matter content, and fecal calprotectin levels.

RESULTS

Most infants had a soft/formed stool consistency, although odds for hard stools were different between groups. Gastrointestinal symptom scores revealed significant differences for burping and diarrhea, while other symptoms did not differ between groups. No significant differences between groups were found for stool frequency, dry matter content, and fecal pH. Although calprotectin was within the expected healthy ranges, significant differences among groups were seen. Furthermore, calprotectin significantly correlated with the severity of the gastrointestinal symptoms burping, flatulence, abdominal distension, and diarrhea.

CONCLUSIONS

Differences in stool characteristics and specific differences in gastrointestinal symptoms were observed between different formula brand users. This may potentially be explained by the different composition and processing of the formulae, although there are multiple factors that influence the assessed outcomes.

TRIAL REGISTRATION

The study was registered in the Netherlands Trial Registry (NL7805), linked to https://trialsearch.who.int/ , on 11/06/2019.

Sedentary behaviour and brain health in middle-aged and older adults: a systematic review

Sedentary behaviour may increase the risk of dementia. Studying physiological effects of sedentary behaviour on cerebral health may provide new insights into the nature of this association. Accordingly, we reviewed if and how acute and habitual sedentary behaviour relate to brain health factors in middle-aged and older adults (≥45 years). Four databases were searched. Twenty-nine studies were included, with mainly cross-sectional designs. Nine studies examined neurotrophic factors and six studied functional brain measures, with the majority of these studies finding no associations with sedentary behaviour. The results from studies on sedentary behaviour and cerebrovascular measures were inconclusive. There was a tentative association between habitual sedentary behaviour and structural white matter health. An explanatory pathway for this effect might relate to the immediate vascular effects of sitting, such as elevation of blood pressure. Nevertheless, due to the foremost cross-sectional nature of the available evidence, reverse causality could also be a possible explanation. More prospective studies are needed to understand the potential of sedentary behaviour as a target for brain health.

Hemodynamic and structural brain measures in high and low sedentary older adults

Due to its cardiovascular effects sedentary behaviour might impact cerebrovascular function in the long term, affecting cerebrovascular regulatory mechanisms and perfusion levels. Consequently this could underly potential structural brain abnormalities associated with cognitive decline. We therefore assessed the association between sedentary behaviour and brain measures of cerebrovascular perfusion and structural abnormalities in community-dwelling older adults. Using accelerometery (GENEActiv) data from The Irish Longitudinal Study on Ageing (TILDA) we categorised individuals by low- and high-sedentary behaviour (≤8 vs >8 hours/day). We examined prefrontal haemoglobin oxygenation levels using Near-Infrared Spectroscopy during rest and after an orthostatic challenge in 718 individuals (66 ± 8 years, 52% female). Global grey matter cerebral blood flow, total grey and white matter volume, total and subfield hippocampal volumes, cortical thickness, and white matter hyperintensities were measured using arterial spin labelling, T1, and FLAIR MRI in 86 individuals (72 ± 6 years, 55% female). While no differences in prefrontal or global cerebral hemodynamics were found between groups, high-sedentary individuals showed lower hippocampal volumes and increased white matter hyperintensities compared to their low-sedentary counterparts. Since these structural cerebral abnormalities are associated with cognitive decline and Alzheimer's disease, future work exploring the causal pathways underlying these differences is needed.

Is there a bidirectional association between sedentary behaviour and cognitive decline in older adults? Findings from the Irish Longitudinal Study on Ageing

Research on whether sedentary behaviour (SB) is related to cognitive decline in older individuals is conflicting, potentially caused by methodological differences in previous studies. To inform public health policies, we analysed both the forward and reverse association across four-years between subjective TV time and objectively-measured SB and four cognitive outcome measures in older adults. The Irish Longitudinal Study on Ageing (TILDA) quantified time spent watching TV using a questionnaire and objective physical activity patterns with a GENEActiv accelerometer. Mixed model analysis examined whether these two measures of SB related to changes in cognitive function (immediate and delayed recall, MMSE, and animal naming task) during a four-year follow-up period. Furthermore, the reverse association between changes in cognition over the preceding four years and SB was investigated. We included 1,276 participants (67 ± 9 years). Longitudinally, every hour of objective SB per day was associated with a -0.01 (95%CI = -0.03;-0.00) lower MMSE score per year. Reversely, a worse decline in immediate and delayed recall over the preceding waves was related to slightly more objective SB (B = -0.24 (95%CI = -0.41;-0.07)) and TV time (B = -0.25 (95%CI = -0.48;-0.03)) at the end of those four years. To conclude, in healthy older individuals, higher levels of objective SB are related to cognitive decline across a four-year follow-up, although the magnitude and clinical relevance are questionable. As preceding cognitive decline is associated with more SB across follow-up, this suggests that a bidirectional association is plausible.

Objectively-Measured Activity Patterns are Associated with Home Blood Pressure in Memory Clinic Patients

Background:

Physicians are cautious to prescribe antihypertensive drugs in frail older adults because of the potential adverse effects, especially in those with cognitive complaints. Lifestyle aspects might provide safe targets to lower blood pressure in older adults.

Objective:

Our goal was to evaluate the associations between activity patterns and blood pressure in memory clinic patients.

Methods:

We used an observational cross-sectional study to measure activity patterns with the ActivPAL accelerometer, and simultaneous home blood pressure levels in memory clinic patients (age range 51–87 years old). Office blood pressure was assessed during routine clinical practice.

Results:

41 patients (mean age of 74.3 (7.7) years of age, 46% female) were included. Sedentary parameters were associated with higher mean home blood pressure, with the strongest correlation between more prolonged sitting bouts and higher SBP (r = 0.58, p < .0001). Physical activity parameters were negatively associated with mean home blood pressure. Adjusted regression estimates remained significant, showing, e.g., a 4.5 (95% CI = 1.6;7.4) mmHg increase in SBP for every hour of sitting per day and a –1.0 (95% CI = –1.8;–0.2) mmHg decrease in DBP for every additional 1000 steps per day. No strong correlations were found between any of the activity pattern variables and office blood pressure.

Conclusion:

Associations between activity pattern variables and blood pressure were only found with home blood pressure measurements, not with office measurements. Longitudinal evaluations of these associations are now needed to explore if reducing prolonged sedentary bouts and increasing step count indeed serve as safe targets to lower blood pressure.

The short-term effects of sedentary behaviour on cerebral hemodynamics and cognitive performance in older adults: a cross-over design on the potential impact of mental and/or physical activity

BACKGROUND

Sedentary behaviour might be a potential risk factor for cognitive decline. However, the short-term effects of sedentary behaviour on (cerebro) vascular and cognitive performance in older people are unknown.

METHODS

We used a cross-over design with 22 older adults (78 years, 9 females) to assess the short-term hemodynamic and cognitive effects of three hours uninterrupted sitting and explored if these effects can be counteracted with regular (every 30 min) two-minute walking breaks. In addition, we investigated if low versus high mental activity during the three hours of sitting modified these effects. Before and after each condition, alertness, executive functioning, and working memory were assessed with the Test of Attentional Performance battery. Additionally, cerebral blood flow velocity (Transcranial Doppler) and blood pressure (Finapres) were measured in rest, and during sit-to-stand and CO₂ challenges to assess baroreflex sensitivity, cerebral autoregulation, and cerebral vasomotor reactivity.

RESULTS

No short-term differences were observed in cognitive performance, cerebral blood flow velocity, baroreflex sensitivity, cerebral autoregulation, or cerebral vasomotor reactivity across time, or between conditions. Blood pressure and cerebrovascular resistance increased over time (8.6 mmHg (5.0;12.1), p < 0.001), and 0.23 in resistance (0.01;0.45), p = 0.04). However, these effects were not mitigated by mental activity or by short walking breaks to interrupt sitting.

CONCLUSIONS

In older individuals, three hours of sitting did not influence cognitive performance or cerebral perfusion. However, the sitting period increased blood pressure and cerebrovascular resistance, which are known to negatively impact brain health in the long-term. Importantly, we found that these effects in older individuals cannot be mitigated by higher mental activity and/or regular walking breaks.

TRIAL REGISTRATION

Clinical trial registration URL: https://www.toetsingonline.nl/. Unique identifier: NL64309.091.17. Date of registration: 06-02-2018.

The Association of Sedentary Behaviour and Cognitive Function in People Without Dementia: A Coordinated Analysis Across Five Cohort Studies from COSMIC

BACKGROUND

Besides physical activity as a target for dementia prevention, sedentary behaviour is hypothesized to be a potential target in its own right. The rising number of persons with dementia and lack of any effective treatment highlight the urgency to better understand these modifiable risk factors. Therefore, we aimed to investigate whether higher levels of sedentary behaviour are associated with reduced global cognitive functioning and slower cognitive decline in older persons without dementia.

METHODS

We used five population cohorts from Greece, Australia, USA, Japan, and Singapore (HELIAD, PATH, SALSA, SGS, and SLAS2) from the Cohort Studies of Memory in an International Consortium. In a coordinated analysis, we assessed the relationship between sedentary behaviour and global cognitive function with the use of linear mixed growth model analysis (mean follow-up range of 2.0-8.1 years).

RESULTS

Baseline datasets combined 10,450 older adults without dementia with a mean age range between cohorts of 66.7-75.1 years. After adjusting for multiple covariates, no cross-sectional association between sedentary behaviour and cognition was found in four studies. One association was detected where more sedentary behaviour was cross-sectionally linked to higher cognition levels (SLAS2, B = 0.118 (0.075; 0.160), P < 0.001). Longitudinally, there were no associations between baseline sedentary behaviour and cognitive decline (P > 0.05).

CONCLUSIONS

Overall, these results do not suggest an association between total sedentary time and lower global cognition in older persons without dementia at baseline or over time. We hypothesize that specific types of sedentary behaviour may differentially influence cognition which should be investigated further. For now, it is, however, too early to establish undifferentiated sedentary time as a potential effective target for minimizing cognitive decline in older adults without dementia.

Rationale for Dietary Antioxidant Treatment of ADHD

Increasing understanding arises regarding disadvantages of stimulant medication in children with ADHD (Attention-Deficit Hyperactivity Disorder). This review presents scientific findings supporting dietary antioxidant treatment of ADHD and describes substantial alterations in the immune system, epigenetic regulation of gene expression, and oxidative stress regulation in ADHD. As a result, chronic inflammation and oxidative stress could develop, which can lead to ADHD symptoms, for example by chronic T-cell-mediated neuroinflammation, as well as by neuronal oxidative damage and loss of normal cerebral functions. Therefore, modulation of immune system activity and oxidant-antioxidant balance using nutritional approaches might have potential in ADHD treatment. The use of natural antioxidants against oxidative conditions is an emerging field in the management of neurodegenerative diseases. Dietary polyphenols, for example, have antioxidant capacities as well as immunoregulatory effects and, therefore, appear appropriate in ADHD therapy. This review can stimulate the development and investigation of dietary antioxidant treatment in ADHD, which is highly desired.