173 ASSOCIATIONS BETWEEN CARDIOVASCULAR SIGNAL ENTROPY AND FUTURE FALLS, SYNCOPE, AND FEAR OF FALLING

Background

Previous studies have reported impaired blood pressure (BP) control during standing to be associated with future falls and syncope. Increased complexity in BP signals has been shown to be associated with poorer cognitive performance, frailty, and increased mortality risk. The aim of this study was to investigate associations between the level of complexity in beat-to-beat BP data during an active stand challenge and future occurrence of falls, syncope, and fear of falling in a cohort of older adults from The Irish Longitudinal Study on Ageing (TILDA).

Methods

Beat-to-beat BP was continuously measured during an active stand protocol at wave 1 of TILDA (2009-2011). Complexity of BP signals was quantified using sample entropy (SampEn) during rest, stand, and recovery sections of data. Self-reported occurrences of falls, syncope, and fear of falling were collected at waves 2 to 6 (2012-2021). Comprehensively controlled modified Poisson modelling was employed to investigate associations.

Results

Complete data were available for 4714 individuals (age: 61.0±8.8 years; 55.3% female). Higher BP SampEn during rest and stand was associated with increased risk of future recurrent falls (IRR=1.34, p=0.003, and IRR=1.22, p=0.044, respectively). Higher BP SampEn during recovery was associated with increased risk of future syncope (IRR=1.84, p=0.041). In a sub-cohort of participants aged 65+, higher BP SampEn was associated with increased risk of future fear of falling (N=1552; IRR=1.25, p=0.037). All reported IRRs are per one unit of SampEn.

Conclusion

This study reports significant associations between higher complexity in BP data during an active stand protocol and increased risk of future falls, syncope, and fear of falling over ten-year follow-up.

34 RELATIONSHIP BETWEEN SERUM CAROTENOID CONCENTRATIONS AND FRAILTY, PROBABLE SARCOPENIA, AND PHYSICAL FUNCTION IN THE IRISH LONGITUDINAL STUDY ON AGEING (TILDA)

Background

Lutein and zeaxanthin are antioxidant and anti-inflammatory carotenoids derived from foods such as fruit and vegetables. Serum concentrations of Lutein (Ls) and Zeaxanthin (Zs) reflect habitual dietary intake. This study examined the cross-sectional and longitudinal relationships between Ls and Zs and frailty, probable sarcopenia, and indices of physical function in TILDA.

Methods

The cross-sectional analysis included n=4672 community-dwelling adults aged ≥50 years with Ls and Zs at Wave 1 (2010). For the longitudinal analyses, changes in usual gait speed (at Wave 3, 2014), grip strength (Wave 4, 2016) and Timed Up-and-Go (TUG; Wave 5, 2018), incident probable sarcopenia (defined as grip strength <27 kg in men, <16 kg in women, at Wave 4) and incident frailty (Fried, at Wave 5) were determined. Multivariable linear and logistic regression analyses were adjusted for age, sex, waist circumference, education, malnutrition, smoking, chronic disease, alcohol intake and physical activity.

Results

Cross-sectionally, Ls and Zs were positively associated with gait speed (B [95% CI] per 100-nmol/L higher concentration: Ls 0.67 [0.22, 1.12], Zs 1.3 [0.21, 2.48] cm/s) and inversely associated with TUG time (Ls –0.07 [-0.11, –0.02], Zs –0.14 [-0.25, –0.03] s) and with frailty (OR: Ls 0.61 [0.42, 0.87], Zs 0.23 [0.08, 0.68]), all p <0.05), but not with grip strength or probable sarcopenia. Longitudinally, Ls was inversely associated incident frailty (OR 0.85 [0.04, 0.84], p=0.03), whereas Zs was not (0.83 [0.56, 1.23], p=0.36). Neither Ls or Zs were related to changes in physical function measures or incident probable sarcopenia (p>0.05).

Conclusion

Cross-sectionally, lower Ls and Zs were independently associated with frailty, slower gait speed and worse TUG performance. However, Wave 1 Ls and Zs were not predictive of changes in these outcomes over 4-8 years of follow up, with the exception of Ls which was inversely associated with incident frailty after 8 years.

121 INVESTIGATING THE RELATIONSHIP BETWEEN PROBABLE SARCOPENIA AND ORTHOSTATIC HYPOTENSION: FINDINGS FROM THE IRISH LONGITUDINAL STUDY ON AGEING

Background

Sarcopenia and Orthostatic Hypotension (OH) are emerging age-related health burdens associated with adverse outcomes including falls and functional decline. Despite a possible pathophysiological link, the association between the two disorders is not well established. We sought to further investigate this relationship in The Irish Longitudinal Study on Ageing (TILDA).

Methods

Data from 2,858 participants at wave 3 of TILDA was analysed. Probable sarcopenia was defined as per the European Working Group on Sarcopenia in Older People revised cut-offs: Hand-Grip Strength (HGS) <27kg in men, <16kg in women and/or five-chair stand test (5CST) time >15s. Participants underwent an active stand orthostatic test with non-invasive beat-to-beat blood pressure monitoring. Multivariable logistic regression models adjusting for age, sex, anthropometrics, cardiovascular diseases, medications and fear of falling were used to determine whether probable sarcopenia was a predictor of OH at multiple time-points after standing.

Results

In multivariable analysis, HGS was an independent predictor of OH at 30s, 40s, 60s (P<0.01), 120s and 180s (P<0.05) but not initial OH at 10s or 20s (P=0.531, 0.464) or consensus OH (P=0.064). 5CST time was only associated with OH at 120s (P=0.030). At follow up in wave 5, four years later, those with HGS-defined probable sarcopenia had higher proportions of recurrent falls (10.5% vs 5.7%, P = 0.014), fear of falling with activity limitation (12.4% vs 6.9%, P = 0.011), hospital admission (24.2% vs 12.5%, P < 0.001) and death (4.8% vs 1.9%, P = 0.006) when compared to the non-sarcopenic group.

Conclusion

Probable sarcopenia as measured by HGS, but not 5CST time is an independent predictor of orthostatic hypotension, especially in the blood pressure recovery phase 30-60s after standing. The increased rates of adverse outcomes in this group underline the importance of identification of probable sarcopenia in those at risk of OH and falls.

212 FATIGUE EXPERIENCED BY ADULTS WITH LONG-COVID WAS NOT ASSOCIATED WITH AN EMG-DERIVED MUSCLE FATIGUE INDEX

Background

One of the most prominent challenges of the COVID-19 pandemic is the emergence of the post-COVID-19 syndrome or ‘long-COVID’ following the acute phase of the viral infection. With a plethora of debilitating symptoms across many physiological systems, the pathophysiology of long-COVID remains elusive and subject of intense research efforts. Adults with long COVID are often affected by prolonged fatigue, which could be linked to neuromuscular function impairment. We hypothesised that there might be a correlation between subjective fatigue and an Electromyograph(EMG)-derived muscle fatigue index in adults with long-COVID.

Methods

As part of a neuro-cardiovascular instability assessment protocol, participants were asked to squeeze the thigh muscles as hard as possible for ten seconds during both supine resting and after active and passive standing (head-up tilt) tests. Surface EMG was used to capture on each leg the physiological activity of the vastus lateralis and rectus femoris during the squeezes, from which the muscle fatigue index was computed based on both the mean and median frequencies of each 10-second maximum prompted muscle contraction. Using two-sided Spearman correlation coefficients, we examined the associations between the muscle fatigue indices and self-reported fatigue measured by the Chalder Fatigue Scale (CFQ).

Results

108 participants were included, 77 female and 31 male, with a mean age of 46 (range 25-78) years, 22% of whom were hospitalised in the acute phase of SARS-CoV-2 infection. Strong intercorrelations were found between the muscle fatigue indices derived from the mean and median frequencies of thigh muscle contractions. However, no significant correlations were detected between the muscle fatigue indices and CFQ scores.

Conclusion

Self-reported fatigue as measured by the CFQ was not associated with an EMG-derived muscle fatigue index in this long-COVID cohort.

76 PREDICTIVE MODEL FOR MOBILITY DECLINE: INDIVIDUAL TRIAL MISTAKE THRESHOLDS IN SUSTAINED ATTENTION TO RESPONSE TASK (SART)

Background

The Sustained Attention to Response Task (SART) is a standard computer-based cognitive test designed to measure the sustained attention, fundamental for completing tasks that require supervision over time (Robertson et al., 1997). However, commonly used average features may result in loss of information and data misinterpretation, leading to inability to detect clinically expected associations (O’Halloran et al., 2014).

Methods

Here, we present a new method to visualise the full information obtained from the SART test, ordering by age, and categorising in groups based on mobility status in a large population-based study of ageing in Ireland. A new threshold, derived from the visualisation and based on the individual trial number of mistakes, was employed to individuate poorer SART performances, and to predict mobility and cognitive decline after 4 years in binary logistic regression models.

Results

Raw SART data were available for 4,864 participants aged 50 years and over at baseline. The new variable bad performances, expressing the number of SART trials with at least 4 mistakes, was the most significant predictor of mobility decline, defined as the transition from Timed Up-and-Go (TUG) < 12 to TUG ≥12 seconds (Odds Ratio (OR) = 1.29; 95% Confidence Interval (CI) 1.14–1.46; p < 0.001), and the only significant predictor of new falls (OR = 1.11; 95% CI 1.03–1.21; p = 0.011) compared to traditional SART variables in models adjusted for multiple covariates. No SART-related variables resulted significant predictors of cognitive decline, defined as a decrease of at least 2 points in the Mini-Mental State Examination (MMSE) score.

Conclusion

This multimodal visualisation and the new threshold approach could help clinicians to easily develop relevant hypotheses, and better identify subjects at higher risk of future mobility decline.

57 POTENTIALLY INAPPROPRIATE MEDICATION USE AND MORTALITY IN PATIENTS WITH COGNITIVE IMPAIRMENT

Background

Potentially inappropriate medications (PIMs are associated with falls, hospitalisation, and cognitive decline. Few studies have investigated the association between PIMs related to cognitive impairment (PIMCog) and mortality in dementia or mild cognitive impairment (MCI).

Methods

This was a retrospective observational study. Patients diagnosed with MCI or dementia (DSM-IV criteria) presenting to a tertiary-referral memory clinic from 2013–2019 were eligible. The primary outcome was all-cause death. Secondary outcomes were vascular death and non-vascular death defined according to formal certification. The primary exposure variable of interest was PIMCog, defined as any medication in the Beers 2015 or STOPP criteria, classified as potentially inappropriate for patients with cognitive impairment. Anticholinergic burden was measured using the anticholinergic cognitive burden (ACB) scale. Polypharmacy was defined as ≥5 medications. Cox proportional hazard models were used to calculate hazard ratios (HRs) and 95% confidence intervals (95% CIs).

Results

There were 418 patients included (n = 261 dementia, n = 157 MCI). The median age was 79 (interquartile range {IQR} 74–82) and median follow-up was 809 days (IQR 552–1,571). One or more PIMCog was prescribed in 141 patients (33.4%). PIMCog use was associated with all-cause mortality after adjustment for age, sex, dementia severity, Charlson Co-morbidity Index, chronic obstructive pulmonary disease, congestive cardiac failure, and peripheral vascular disease (HR 1.96, 95% CI 1.24–3.09). PIMCog use was associated with vascular death (HR 3.28, 95% CI 1.51–7.11) but not with non-vascular death (HR 1.40 95% CI: 0.78–2.52). Neither an ACB ≥3 (HR 0.87, 95% CI: 0.46–1.64) or polypharmacy (HR 1.87, 95% CI: 0.67–5.24) were associated with death.

Conclusion

The burden of PIMCog use in patients with cognitive impairment is high. PIMCog use is independently associated with all-cause mortality and vascular death. This is a potential modifiable risk factor for death in patients with neurocognitive disorders. Further research is required to independently validate this finding.

81 LONGER CHAIR-STAND TIME IS ASSOCIATED WITH ORTHOSTATIC INTOLERANCE IN AN OLDER IRISH POPULATION

Background

Hospital admissions for orthostatic hypotension (OH) have risen more than two-fold in the past ten years. OH can lead to orthostatic intolerance (OI), and both OH and OI are common causes of falls and injuries in older persons. Sarcopenia is also common in older persons and associated with adverse health outcomes. The 5-chair stand test (5-CST) can be used as a marker of sarcopenia and a cut-off of 15 s has been proposed. We hypothesized that those with a worse performance on the 5-CST would be at greater risk of OH and sought to investigate this in an older Irish population cohort study.

Methods

5-CST was measured in keeping with a standardised protocol. Beat-to-beat blood pressure was measured with the Finometer device according to the active stand protocol. Multivariable logistic regressions were performed to investigate the associations between OH at 40 seconds after standing (OH40), OI (dizziness after standing), and 5-CST time. Potential confounders were controlled for in the model including age, sex, education, body mass index and medications.

Results

Data from 3,119 participants were available for analysis. Mean age was 63.8 years, 55% were female, 25% took longer than 15s on the 5-CST and mean baseline blood pressure was 141/76 mmHg. Proportion of OH40 was 12.5% and 4.4% reported OI. In the multivariable model, OH40 was not independently associated with 5-CST time after controlling for age (p > 0.05). Worse performance on the chair stands test was however an independent predictor of OI (odds ratio 1.06, p = 0.039).

Conclusion

Longer time taken on the 5-CST, a marker of sarcopenia, was an independent predictor of OI in a large population study. The relationship between sarcopenia and orthostatic blood pressure response is not well elucidated. We plan to further investigate this area in a future clinical cohort.

123 ACUTE-PHASE BED-REST DURATION WAS ASSOCIATED WITH LOWER GRIP STRENGTH IN A POST-COVID-19 COHORT

Background

Though age-related muscle loss is traditionally associated with older cohorts, strong evidence suggests a life-spanning precipitation of decreasing muscle mass and strength beginning as early as the fourth decade of life, with established deleterious consequences for later-life morbidity and mortality. Periods of low activity and bed rest (LA/BR) can further compound this depletion of muscle strength. Our aim was to examine such associations in a post-COVID-19 cohort.

Methods

Participants reporting ongoing symptomatology and fatigue post COVID-19 underwent assessments of grip strength via hand-held dynamometry (2 measures on each hand). Demographics of COVID-19 illness, including time since diagnosis, duration of LA/BR during acute illness, and levels of fatigue were captured via self-reported questionnaires. Independent predictors of mean grip strength were investigated using a linear regression model.

Results

Forty-nine participants underwent assessments (69% female, mean age 44(12) years). At the time of assessment, days post COVID-19 diagnosis ranged from 39–522 (mean 262(140)). The mean self-reported period of LA/BR during the acute illness was 15(18) days. In general, participants reported significant levels of fatigue (median Chalder Fatigue Scale score 22(8)). Mean grip strength was 41.3(6.3) Kg for men and 22.8(6.7) Kg for women. When predictors of grip strength were investigated, an increased duration of LA/BR was found to be associated with lower grip strength, independently of age, gender, time since COVID-19 diagnosis, and self-reported fatigue (Beta = −0.158, 95% Confidence Interval − 0.242 to −0.074, p = 0.001).

Conclusion

In this cohort, every day of LA/BR during acute COVID-19 illness was independently associated with subsequent lower grip strength of approximately 150 g. These results underscore the importance of early mobilization and discouraging bed rest in the acute phase of COVID-19. Patients who are isolating should be encouraged to maintain physical activity and muscle strength as part of a modified isolation-friendly rehabilitation programme.

78 HIGHER NEUROVASCULAR SIGNAL ENTROPY IS ASSOCIATED WITH ACCELERATED BRAIN AGEING

Background

Often chronological age is not the most accurate marker of an individual’s health status since ageing is a heterogeneous process across individuals. Machine learning can be used to quantify the relationship between structural brain MRI data and chronological age, to estimate an individual’s ‘brain age’, which, when subtracted from chronological age, provides a brain predicted-age difference score (BrainPAD) [1]. BrainPAD reflects the biological ageing of the brain. Increased complexity in neurovascular signals has been shown to be associated with poorer cognitive performance and physical frailty [2]. The aim of this study was to investigate associations between the complexity of frontal-lobe oxygenation (tissue saturation index (TSI)) data and BrainPAD in a cohort of older community-dwelling adults.

Methods

To calculate BrainPAD, machine learning was applied to 1,359 T1-weighted MRI brain scans from various open-access repositories, and this model was subsequently applied to MRI data acquired from the study cohort. TSI was non-invasively measured in the left frontal lobe using near-infrared spectroscopy. TSI data were acquired continuously during five minutes of supine rest and the last minute was utilized in this analysis. The complexity of TSI signals was quantified using sample entropy (SampEn). Multivariable linear regression was employed, controlling for age, sex, education, antihypertensive medications, diabetes, cardiovascular conditions, smoking, alcohol, depression, BMI, physical activity, and blood pressure.

Results

Complete data were available for 397 individuals (age: 67.9 ± 7.7 years; 53.7% female). An increase in TSI SampEn of 0.1 was associated with an increase in BrainPAD of 0.9 years (P = 0.007, 95%CIs: 0.3 to 1.6). Similar results were found with and without the inclusion of chronological age in the models.

Conclusion

This study reports significant associations between higher complexity in peripherally measured frontal lobe oxygenation concentration and accelerated brain ageing.

References

1. Boyle R. et al. Brain Imaging and Behavior. 15,327–345 (2021) https://doi.org/10.1007/s11682-020-00260-3.

2. Knight S. et al. Entropy. 23(1):4 (2021) https://doi.org/10.3390/e23010004.

509 POTENTIALLY INAPPROPRIATE MEDICATION USE AND MORTALITY IN PATIENTS WITH COGNITIVE IMPAIRMENT

Introduction

Potentially inappropriate medications (PIMsare associated with falls, hospitalisation, and cognitive decline. Few studies have investigated the association between PIMsrelated to cognitive impairment (PIMCog) and mortality in dementia or mild cognitive impairment (MCI).

Methods

This was a retrospective observational study. Patients diagnosed with MCI or dementia (DSM-IV criteria) presenting to a tertiary-referral memory clinic from 2013–2019 were eligible. The primary outcome was all-cause death. Secondary outcomes were vascular death and non-vascular death defined according to formal certification. The primary exposure variable of interest was PIMCog, defined as any medication in the Beers 2015 or STOPP criteria, classified as potentially inappropriate for patients with cognitive impairment. Anticholinergic burden was measured using the anticholinergic cognitive burden (ACB) scale. Polypharmacy was defined as ≥5 medications. Cox proportional hazard models were used to calculate hazard ratios (HRs) and 95% confidence intervals (95% CIs).

Results

There were 418 patients included (n = 261 dementia, n = 157 MCI). The median age was 79 (interquartile range {IQR} 74–82) and median follow-up was 809 days (IQR 552–1,571). One or more PIMCog was prescribed in 141 patients (33.4%). PIMCog use was associated with all-cause mortality after adjustment for age, sex, dementia severity, Charlson Co-morbidity Index, chronic obstructive pulmonary disease, congestive cardiac failure, and peripheral vascular disease. (HR 1.96, 95% CI 1.24–3.09). PIMCog use was associated with vascular death (HR 3.28, 95% CI 1.51–7.11) but not with non-vascular death (HR 1.40 95% CI: 0.78–2.52). Neither an ACB ≥3 (HR 0.87, 95% CI: 0.46–1.64) or polypharmacy (HR 1.87, 95% CI: 0.67–5.24) were associated with death.

Conclusion

The burden of PIMCog use in patients with cognitive impairment is high. PIMCog use is independently associated with all-cause mortality and vascular death. This is a potential modifiable risk factor for death in patients with neurocognitive disorders. Further research is required to independently validate this finding.

Disseminating Cultural Neuropsychology Research: Five Key Recommendations for Skill Development

Objective

Cultural neuropsychology has been called upon to meet the demand for more empirical tools and frameworks to use with our diverse populations. While much is being done, we have largely been “playing a game of catch-up” (Manly, 2008) and researchers have been encouraged to reinvent their approaches (Suchy, 2016). In this regard, one area of opportunity is promoting the development of cultural neuropsychology research dissemination.

Method

Relevant literature and professional experiences were used to identify cultural neuropsychology research dissemination barriers and solutions.

Outcomes

(1) Researches should use empirically supported knowledge dissemination frameworks to guide their approaches (Wilson et al., 2010). (2) Care should be taken to report study variables in internationally compatible/meaningful units (e.g., education, socioeconomic status; UNESCOIS, 2012). Researchers are also encouraged to find opportunities to comment on the purposeful exclusion of “North-American” variables (e.g., ethnicity) as well as the lessons learned from research “failures” (Hruschka et al., 2018). (3) Findings should be presented in ways that make clinical application easily comprehensible and implementable, even for those not specializing in cultural neuropsychology (e.g., use clear titles, clarify “insider” knowledge). (4) Researchers can and should negotiate with journals to make available the translated manuscripts and supplemental materials to improve research accessibility. (5) Professional collaboration and research visibility are fundamental to the success of dissemination (Tripathy et al., 2017).

Discussion

Neuropsychologists are eager for more culturally informed and clinically applicable research. Thus, cultural neuropsychology researchers focusing on developing their dissemination skills in these five highlighted areas are well positioned to increase the impact of their work and promote growth within cultural neuropsychology specifically, and neuropsychology broadly.

References

Hruschka, D. J., Munira, S., Jesmin, K., Hackman, J., & Tiokhin, L. (2018). Learning from failures of protocol in cross-cultural research. Proceedings of the National Academy of Sciences, 115(45), 11428-11434. Manly, J. J. (2008). Critical issues in cultural neuropsychology: profit from diversity. Neuropsychological Review, 18(3), 179-183. Suchy, Y. (2016). Population-based norms in crisis. The Clinical Neuropsychologist, 30(7), 973-974. Tripathy, J. P., Bhatnagar, A., Shewade, H. D., Kumar, A. M. V., Zachariah, R., & Harries, A. D. (2017). Ten tips to improve the visibility and dissemination of research for policy makers and practitioners. Public Health Action, 7(1), 10-14. UNESCO Institute for Statistics. (2012). International Standard Classification of Education: ISCED 2011. Montreal: UNESCO Institute for Statistics. Wilson, P. M., Petticrew, M., Calnan, M. W., & Nazareth, I. (2010). Disseminating research findings: what should researchers do? A systematic scoping review of conceptual frameworks. Implementation Science, 5(1), 91.

Diaphragmatic eventration presenting as a recurrent diaphragmatic hernia

Diaphragmatic eventration is an uncommon condition, usually discovered incidentally in asymptomatic patients. Even in symptomatic patients, the diagnosis can be challenging and should be considered among the differential diagnoses of diaphragmatic hernia. The correct diagnosis can often only be made in surgery. We describe the case of a 31-year-old patient with diaphragmatic eventration that was misdiagnosed as a recurrent congenital diaphragmatic hernia and review the corresponding literature.

Chinese whispers in the post anaesthesia care unit (PACU)

We audited verbal handover of information by anaesthetists to recovery room nurses based on Situation, Background, Assessment and Recommendation. In Audit A, 100 handovers for elective procedures were included. For audit B, a second cohort of 100 patients was examined post educational session. There was an improvement in handover of medical background (46.15% Audit A, 77% Audit B, p < 0.001) and allergy status (42% Audit A, 56% Audit B, p = 0.048). Handing over immediate postoperative instructions remained unchanged (58% Audit A, 59% Audit B) and there was a 4% decline in verbal handover of instructions for ward care. Nurse satisfaction with handovers improved by 12%. We conclude that a structured process of information transfer, led to improved handover of immediate care. Further education focussed on the importance of instructions for the ward to maintain continuity of care is recommended.

Site differences in mild cognitive dysfunction (MCD) among patients with systemic lupus erythematosus (SLE)

Background

Mild cognitive dysfunction (MCD) is common in patients with systemic lupus erythematosus (MCD-SLE) but few studies have investigated potential site differences.

Methods

SLE patients from Denver, CO, and New York, NY, were enrolled in two different cognition studies employing similar screening methods. Using the resulting neuropsychological scores, cognitive impairment was calculated using a cognitive impairment index (CII).

Results

The rate of MCD-SLE was 24% at the Denver, CO, site and 60% at the New York, NY, site. The mean CII was 2.6 ± 2.3 versus 4.4 ± 2.7, respectively ( p = 0.005). The NY participants had a significantly longer disease duration ( p = 0.13) and higher American College of Rheumatology SLE criteria scores ( p > 0.001). NY participants had a higher frequency of impairment in semantic verbal fluency ( p = 0.005), visuomotor speed ( p = 0.013), and motor sequencing ( p = 0.001). A correlation was found between cognitive impairment and SLE disease duration ( p = 0.03).

Conclusions

The rate of MCD-SLE was greater in SLE patients from New York, NY, compared to patients in the Denver, CO, area. The greater duration of disease and higher prevalence of medical complications in the NY group might contribute to this difference. Findings suggest that MCD-SLE may differ by site, but future studies that better evaluate site or selection bias are recommended.

Infant feeding and allergy prevention: a review of current knowledge and recommendations. A EuroPrevall state of the art paper

The relationship between infant feeding patterns and the later development of food allergies has been the focus of much debate and research over the last decade. National recommendations have been made by many countries on how to feed infants to reduce the risk of food allergy but due to the lack of firm evidence the recommendations differ widely. This review has been developed as part of EuroPrevall, a European multicentre research project funded by the European Union, to document the differing feeding recommendations made across Europe, to investigate the current evidence base for any allergy prevention feeding recommendations and to identify areas where further research is needed. This review will also provide information which, when combined with the infant feeding data collected as part of EuroPrevall, will give an indication of compliance to national feeding guidelines which can be utilised to assess the effectiveness of current dissemination and implementation strategies.

Urinary lactic acid dehydrogenase activity and the site of urinary tract infections

A report that elevated urinary lactic acid dehydrogenase (LDH) isoenzyme 5 activity is a reliable tool for separating patients with upper from those with lower urinary tract infections (UTIs) led us to study urinary LDH enzyme activity in girls having bladder washout studies to localize the site of infection. Urinary LDH isoenzyme 5 activity in 64 instances of lower UTI was 16.1 +/- 3.3%, a value not significantly different than that of 18.2 +/- 12.6% found in 26 instances of upper tract infection (t = 0.8726, P = 0.1928). The data show that LDH isoenzyme 5 activity is of no value for localization of the site of a UTI. The data of these studies also showed that urinary LDH enzyme activity clearly separates girls with UTIs from those without infections, but it is unlikely that this finding will be of value in diagnosis or management.

Vascular trauma

Civilian vascular trauma is not uncommon. Prompt treatment with modern vascular surgical techniques produces good results.

Elevated serum creatinine levels in three patients treated with phenacemide

Three adolescent patients with severe seizure disorders were treated with phenacemide. All three patients showed elevated serum creatinine and normal blood urea nitrogen values while on phenacemide. Simultaneous urea and creatinine clearance studies performed on each patient demonstrated normal urea clearances and decreased creatinine clearances. Inulin clearance performed in one patient was normal. The medication was discontinued in two of the patients because of co-existing neutropenia. Serum creatinine values returned to normal after phenacemide treatment was terminated. The elevation in serum creatinine values with phenacemide appears to be dose related, reversible, and unrelated to impairment of glomerular filtration.

Wegener granulomatosis in pediatric patients

Wegener granulomatosis is more easily recognized as a distinct clinical entity than other vasculitides because the initial clinical features frequently include granulomatous vasculitis of the upper and lower respiratory tract and glomerulonephritis. Although the disease has been lethal in the past, prolonged survival and avoidance of end-stage kidney disease can now be expected when cyclophosphamide therapy is introduced early in the course. We report four children with Wegener granulomatosis in whom the initial clinical findings suggested Henoch-Schönlein purpura. In two of the patients Wegener granulomatosis was not recognized until after end-stage kidney disease had developed. The course in these patients emphasizes the need for attention to even scant evidence of inflammation of the upper or lower respiratory tract in patients with glomerulonephritis. Appropriate diagnostic studies may then lead to recognition of Wegener granulomatosis and the prompt institution of appropriate treatment.

Follow-up studies on children with severe dietary chloride deficiency during infancy

Ten children who had severe dietary chloride deficiency during early infancy have grown normally during their first 4 to 5 years. With the exception of one child who did not get into the sitting position alone until he was 9 1/2 months of age, the patients reached the usual developmental milestones of the first 2 years during the expected age intervals. Developmental and psychological testing indicates that all of the children have at least average ability. However, three children have shown behavior patterns that may interfere with successful school performance. Serum creatinine and urea nitrogen concentrations appear to be normal as does renal concentrating capacity. During a 4-year follow-up, one child has shown persistent and a second intermittent microscopic hematuria.

Serum C-reactive protein and the site of urinary tract infections

Elevated surum levels of C-reactive protein have been found regularly in girls with acute clinical pyelonephritis but only infrequently in those with clinical cystitis. Based on these data, the suggestion has been made that elevated serum CRP concentrations may be useful in identifying patients with upper urinary tract infections. In a study in which the bladder washout test was used to localize the site of urinary tract infections, we identified nine girls with renal bacteriuria who did not have clinical findings suggesting acute pyelonephritis; four of these girls had serum CRP concentrations less than 10 micrograms/ml. Twenty-eight girls had bladder washout-proven lower urinary tract infections; three of these had serum CRP values greater than 30 micrograms/ml. These studies show that an elevated serum CRP concentration is not accurate in localizing the site of a urinary tract infection in girls who do not have clinical signs of acute pyelonephritis.

Localization of the site of urinary tract infections with the bladder washout test

The data from 100 bladder washout studies on pediatric patients have been analyzed to derive criteria for interpretation of this test and to define the limitations of this procedure in localization of the site of urinary tract infections. Using the bladder washout test, infection of the upper urinary tract is characterized by an abrupt increase in the concentration of bacteria in urinary specimens collected following urinary bladder sterilization. Infection limited to the lower urinary tract is characterized by scant if any bacterial growth in the specimens of urine collected following bladder sterilization. The site of infection may be incorrectly localized to the lower urinary tract or classified as not determined in patients with scant or intermittent renal bacteriuria.

The dietary chloride deficiency syndrome

Chronic depletion of body chloride developed in a group of infants ingesting a diet consisting almost exclusively of chloride deficient Neo-Mull-Soy. Ten of the 12 infants were on this diet three to five months before loss of appetite, failure to thrive, muscle weakness, and lethargy led to a diagnostic evaluation. The outstanding laboratory features were severe hypokalemic metabolic alkalosis, low urinary chloride concentrations (< 10 mEq/liter), and erythrocyturia. There was marked decrease in weight for age in all 12 infants. Head circumference for age had decreased in five of six and length for age in five of ten infants for whom earlier measurements were available. The biochemical abnormalities reverted to normal following dietary supplementation with either sodium or potassium chloride. Appetite, affect, and muscle strength improved, and weight gain resumed. Head circumference for age has moved toward the percentile level present prior to starting Neo-Mull-Soy in all instances. With one exception, length measurements show a similar pattern. The erythrocyturia has decreased or vanished. Chloride deficiency led to contraction of the extracellular volume and the substitution of poorly reabsorbable anions for readily reabsorbable chloride. These alterations caused development of the negative hydrogen ion and potassium balances which led to the hypokalemic metabolic alkalosis.