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Urine cultures have poor specificity for catheter-associated urinary tract infections (CAUTIs). We evaluated the effect of a urine-culture stewardship program on urine culture utilization and CAUTI in adult intensive care units (ICUs).
Design:
A quasi-interventional study was performed from 2015 to 2017.
Setting and patients:
The study cohort comprised 21,367 patients admitted to the ICU at a teaching hospital.
Intervention:
The urine culture stewardship program included monthly 1-hour discussions with ICU house staff emphasizing avoidance of “pan-culture” for sepsis workup and obtaining urine culture only if a urinary source of sepsis is suspected. The urine culture utilization rate metric (UCUR; ie, no. urine cultueres/catheter days ×100) was utilized to measure the effect. Monthly UCUR, catheter utilization ratio (CUR), and CAUTI rate were reported on an interactive quality dashboard. To ensure safety, catheterized ICU patients (2015–2016) were evaluated for 30-day readmission for UTI. Time-series data and relationships were analyzed using Spearman correlation coefficients and regression analysis.
Results:
Urine culture utilization decreased from 3,081 in 2015 to 2,158 in 2016 to 1,218 in 2017. CAUTIs decreased from 78 in 2015 to 60 in 2016 and 28 in 2017. Regression analysis over time showed significant decreases in UCUR (r, 0.917; P < .0001) and CAUTI rate (r, 0.657; P < .0001). The co-correlation between UCUR and CAUTI rate was (r, 0.625; P < .0001) compared to CUR and CAUTI rate (r, 0.523; P = .004). None of these patients was readmitted with a CAUTI.
Conclusions:
Urine culture stewardship program was effective and safe in reducing UC overutilization and was correlated with a decrease in CAUTIs. Addition of urine-culture stewardship to standard best practices could reduce CAUTI in ICUs.
Environmental risk factors for dementia are poorly understood. Aluminium and fluorine in drinking water have been linked with dementia but uncertainties remain about this relationship.
Aims
In the largest longitudinal study in this context, we set out to explore the individual effect of aluminium and fluoride in drinking water on dementia risk and, as fluorine can increase absorption of aluminium, we also examine any synergistic influence on dementia.
Method
We used Cox models to investigate the association between mean aluminium and fluoride levels in drinking water at their residential location (collected 2005–2012 by the Drinking Water Quality Regulator for Scotland) with dementia in members of the Scottish Mental Survey 1932 cohort who were alive in 2005.
Results
A total of 1972 out of 6990 individuals developed dementia by the linkage date in 2012. Dementia risk was raised with increasing mean aluminium levels in women (hazard ratio per s.d. increase 1.09, 95% CI 1.03–1.15, P < 0.001) and men (1.12, 95% CI 1.03–1.21, P = 0.004). A dose-response pattern of association was observed between mean fluoride levels and dementia in women (1.34, 95% CI 1.28–1.41, P < 0.001) and men (1.30, 95% CI 1.22–1.39, P < 0.001), with dementia risk more than doubled in the highest quartile compared with the lowest. There was no statistical interaction between aluminium and fluoride levels in relation with dementia.
Conclusions
Higher levels of aluminium and fluoride were related to dementia risk in a population of men and women who consumed relatively low drinking-water levels of both.
Anxiety and depression are both important correlates of cognitive function. However, longitudinal studies investigating how they covary with cognition within the same individual are scarce. We aimed to simultaneously estimate associations of between-person differences and within-person variability in anxiety and depression with cognitive performance in a sample of non-demented older people.
Methods
Participants in the Lothian Birth Cohort 1921 study, a population-based narrow-age sample (mean age at wave 1 = 79 years, n = 535), were examined on five occasions across 13 years. Anxiety and depression were measured with the Hospital Anxiety and Depression Scale (HADS) and cognitive performance was assessed with tests of reasoning, logical memory, and letter fluency. Data were analyzed using two-level linear mixed-effects models with within-person centering.
Results
Divergent patterns were observed for anxiety and depression. For anxiety, between-person differences were more influential; people who scored higher on HADS anxiety relative to other same-aged individuals demonstrated poorer cognitive performance on average. For depression, on the other hand, time-varying within-person differences were more important; scoring higher than usual on HADS depression was associated with poorer cognitive performance relative to the average level for that participant. Adjusting for gender, childhood mental ability, emotional stability, and disease burden attenuated these associations.
Conclusions
The results from this study highlight the importance of addressing both between- and within-person effects of negative mood and suggest that anxiety and depression affect cognitive function in different ways. The current findings have implications for assessment and treatment of older age cognitive deficits.
The present study concerns the relation of mental and bodily characteristics to one another during ageing. The ‘common cause’ theory of ageing proposes that declines are shared across multiple, seemingly-disparate functions, including both physical and intellectual abilities. The concept of ‘reserve’ suggests that healthier cognitive (and perhaps bodily) functions from early in life are protective against the effects of senescence across multiple domains. In three waves of physical and cognitive testing data from the longitudinal Lothian Birth Cohort 1936 (n = 1,091 at age 70 years; n = 866 at 73; n = 697 at 76), we used multivariate growth curve modeling to test the ‘common cause’ and ‘reserve’ hypotheses. Support for both concepts was mixed: although levels of physical functions and cognitive functions were correlated with one another, physical functions did not decline together, and there was little evidence for shared declines in physical and mental functions. Early-life intelligence, a potential marker of system integrity, made a significant prediction of the levels, but not the slopes, of later life physical functions. These data suggest that common causes, which are likely present within cognitive functions, are not as far-reaching beyond the cognitive arena as has previously been suggested. They also imply that bodily reserve may be similar to cognitive reserve in that it affects the level, but not the slope, of ageing-related declines.
Approximately half of the variation in wellbeing measures overlaps with variation in personality traits. Studies of non-human primate pedigrees and human twins suggest that this is due to common genetic influences. We tested whether personality polygenic scores for the NEO Five-Factor Inventory (NEO-FFI) domains and for item response theory (IRT) derived extraversion and neuroticism scores predict variance in wellbeing measures. Polygenic scores were based on published genome-wide association (GWA) results in over 17,000 individuals for the NEO-FFI and in over 63,000 for the IRT extraversion and neuroticism traits. The NEO-FFI polygenic scores were used to predict life satisfaction in 7 cohorts, positive affect in 12 cohorts, and general wellbeing in 1 cohort (maximal N = 46,508). Meta-analysis of these results showed no significant association between NEO-FFI personality polygenic scores and the wellbeing measures. IRT extraversion and neuroticism polygenic scores were used to predict life satisfaction and positive affect in almost 37,000 individuals from UK Biobank. Significant positive associations (effect sizes <0.05%) were observed between the extraversion polygenic score and wellbeing measures, and a negative association was observed between the polygenic neuroticism score and life satisfaction. Furthermore, using GWA data, genetic correlations of -0.49 and -0.55 were estimated between neuroticism with life satisfaction and positive affect, respectively. The moderate genetic correlation between neuroticism and wellbeing is in line with twin research showing that genetic influences on wellbeing are also shared with other independent personality domains.
Tests requiring the pronunciation of irregular words are used to estimate premorbid cognitive ability in patients with clinical diagnoses, and prior cognitive ability in normal ageing. However, scores on these word-reading tests correlate with scores on the Mini-Mental State Examination (MMSE), a widely used screening test for possible cognitive pathology. This study aimed to test whether the word-reading tests’ correlations with MMSE scores in healthy older people are explained by childhood IQ or education.
Method
Wechsler Test of Adult Reading (WTAR), National Adult Reading Test (NART), MMSE scores and information about education were obtained from 1024 70-year-olds, for whom childhood intelligence test scores were available.
Results
WTAR and NART were positively correlated with the MMSE (r ≈ 0.40, p < 0.001). The shared variance of WTAR and NART with MMSE was significantly attenuated by ~70% after controlling for childhood intelligence test scores. Education explained little additional variance in the association between the reading tests and the MMSE.
Conclusions
MMSE, which is often used to index cognitive impairment, is associated with prior cognitive ability. MMSE score is related to scores on WTAR and NART largely due to their shared association with prior ability. Obtained MMSE scores should be interpreted in the context of prior ability (or WTAR/NART score as its proxy).
Epidemiological studies have reported inverse associations between various single healthy diet indices and lower levels of systemic inflammation, but rarely are they examined in the same sample. The aim of the present study was to investigate the potential relationships between biomarkers of systemic inflammation (C-reactive protein (CRP) and fibrinogen) and overall foods (dietary patterns), single foods (fruits and vegetables), and specific nutritive (antioxidants) and non-nutritive (flavonoids) food components in the same narrow-age cohort of older adults. The dietary intake of 792 participants aged 70 years from the Lothian Birth Cohort 1936 was assessed using a 168-item FFQ. Models were adjusted for age, sex, childhood cognitive ability, lifestyle factors and history of disease. Using logistic regression analyses, CRP (normal v. elevated) was favourably associated (at P< 0·05) with the ‘health-aware’ (low-fat) dietary pattern (unstandardised β = (0·200, OR 0·82, 95 % CI 0·68, 0·99) and fruit intake (unstandardised β = (0·100, OR 0·91, 95 % CI 0·82, 0·99), including flavonoid-rich apples (unstandardised β = (0·456, OR 0·63, 95 % CI 0·439, 0·946). Using linear regression analyses, fibrinogen (continuous) was inversely associated (at P< 0·05) with the Mediterranean dietary pattern (standardised β = (0·100), fruit intake (standardised β = (0·083), and combined fruit and vegetable intake (standardised β = (0·084). We observed no association between food components (antioxidant nutrients or specific flavonoid subclasses) and inflammatory markers. In the present cross-sectional study, nutrient-dense dietary patterns were associated with lower levels of systemic inflammation in older people. The results are consistent with dietary guidelines that promote a balanced diet based on a variety of plant-based foods.
People with dementia are extremely vulnerable in hospital and unscheduled admissions should be avoided if possible.
Aims
To identify any predictors of general hospital admission in people with dementia in a well-characterised national prospective cohort study.
Method
A cohort of 730 persons with dementia was drawn from the Scottish Dementia Research Interest Register (47.8% female; mean age 76.3 years, s.d. = 8.2, range 50–94), with a mean follow-up period of 1.2 years.
Results
In the age- and gender-adjusted multivariable model (n = 681; 251 admitted), Neuropsychiatric Inventory score (hazard ratio per s.d. disadvantage 1.21, 95% CI 1.08–1.36) was identified as an independent predictor of admission to hospital.
Conclusions
Neuropsychiatric symptoms in dementia, measured using the Neuropsychiatric Inventory, predict non-psychiatric hospital admission of people with dementia. Further studies are merited to test whether interventions to reduce such symptoms might reduce unscheduled admissions to acute hospitals.
We examined the associations between serum cholesterol measures, statin use, and cognitive function measured in childhood and in old age. The possibility that lifelong (trait) cognitive ability accounts for any cross-sectional associations between cholesterol and cognitive performance in older age, seen in observational studies, has not been tested to date.
Methods:
Participants were 1,043 men and women from the Lothian Birth Cohort 1936 Study, most of whom had participated in a nationwide IQ-type test in childhood (Scottish Mental Survey of 1947), and were followed up at about age 70 years. Serum cholesterol measures included total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), triglycerides, and cholesterol:HDL cholesterol ratio. Cognitive outcome measures were age 70 IQ (using the same test as at age 11 years), general cognitive ability (g), processing speed, memory, and verbal ability.
Results:
Higher TC, higher HDL-C, and lower triglycerides were associated with higher age 70 cognitive scores in most cognitive domains. These relationships were no longer significant after covarying for childhood IQ, with the exception a markedly attenuated association between TC and processing speed, and triglycerides and age 70 IQ. In the fully adjusted model, all conventionally significant (p < 0.05) effects were removed. Childhood IQ predicted statin use in old age. Statin users had lower g, processing speed, and verbal ability scores at age 70 years after covarying for childhood IQ, but significance was lost after adjusting for TC levels.
Conclusions:
These results suggest that serum cholesterol and cognitive function are associated in older age via the lifelong stable trait of intelligence. Potential mechanisms, including lifestyle factors, are discussed.
Reports of attitudes to aging from older people themselves are scarce. Which life course factors predict differences in these attitudes is unknown.
Methods:
We investigated life course influences on attitudes to aging in healthy, community-dwelling people in the UK. Participants in the Lothian Birth Cohort 1936 completed a self-report questionnaire (Attitudes to Aging Questionnaire, AAQ) at around age 75 (n = 792, 51.4% male). Demographic, social, physical, cognitive, and personality/mood predictors were assessed, around age 70. Cognitive ability data were available at age 11.
Results:
Generally positive attitudes were reported in all three domains: low Psychosocial Loss, high Physical Change, and high Psychological Growth. Hierarchical multiple regression found that demographic, cognitive, and physical variables each explained a relatively small proportion of the variance in attitudes to aging, with the addition of personality/mood variables contributing most significantly. Predictors of attitudes to Psychosocial Loss were high neuroticism; low extraversion, openness, agreeableness, and conscientiousness; high anxiety and depression; and more physical disability. Predictors of attitudes to Physical Change were: high extraversion, openness, agreeableness, and conscientiousness; female sex; social class; and less physical disability. Personality predictors of attitudes to Psychological Growth were similar. In contrast, less affluent environment, living alone, lower vocabulary scores, and slower walking speed predicted more positive attitudes in this domain.
Conclusions:
Older people's attitudes to aging are generally positive. The main predictors of attitude are personality traits. Influencing social circumstances, physical well-being, or mood may result in more positive attitudes. Alternatively, interventions to influence attitudes may have a positive impact on associated physical and affective changes.
Evidence from observational studies to date suggests that healthy dietary patterns are associated with better cognitive performance in later life. We examined the extent to which childhood intelligence quotient (IQ) and socioeconomic status account for this association.
Methods:
Analyses were carried out on 882 participants in the Lothian Birth Cohort 1936 Study. Four dietary patterns were extracted using principal components analysis of a food frequency questionnaire, namely “Mediterranean-style,” “health aware,” “traditional,” and “sweet foods.” Cognitive function was assessed at the age of 70 years, including general (g) cognitive ability, processing speed, memory, and verbal ability.
Results:
Before adjustment for childhood IQ and socioeconomic status, the “Mediterranean-style” dietary pattern was associated with significantly better cognitive performance (effect size as partial eta-square (ηp2) range = 0.005 to 0.055), and the “traditional” dietary pattern was associated with poorer performance on all cognitive domains measured in old age (ηp2 = 0.009 to 0.103). After adjustment for childhood IQ (measured at the age of 11 years) and socioeconomic status, statistical significance was lost for most associations, with the exception of verbal ability and the “Mediterranean-style” pattern (National Adult Reading Test (NART) ηp2 = 0.006 and Wechsler Test of Adult Reading (WTAR) ηp2 = 0.013), and the “traditional” pattern (NART ηp2 = 0.035 and WTAR ηp2 = 0.027).
Conclusions:
Our results suggest a pattern of reverse causation or confounding; a higher childhood cognitive ability (and adult socioeconomic status) predicts adherence to a “healthy” diet and better cognitive performance in old age. Our models show no direct link between diet and cognitive performance in old age; instead they are related via the lifelong-stable trait of intelligence.
We describe the current, 9-spacecraft Interplanetary Network (IPN). The IPN detects about325 gamma-ray bursts per year, of which about 100 are not localized by any other missions.We give some examples of how the data, which are public, can be utilized.
Clinical depression is associated with reductions in white-matter integrity in several long tracts of the brain. The extent to which these findings are localized or related to depressive symptoms or personality traits linked to disease risk remains unclear.
Method
Members of the Lothian Birth Cohort 1936 (LBC936) were assessed in two waves at mean ages of 70 and 73 years. At wave 1, they underwent assessments of depressive symptoms and the personality traits of neuroticism and extraversion. Brain diffusion magnetic resonance imaging (MRI) data were obtained at the second wave and mood assessments were repeated. We tested whether depressive symptoms were related to reduced white-matter tract fractional anisotropy (FA), a measure of integrity, and then examined whether high neuroticism or low extraversion mediated this relationship.
Results
Six hundred and sixty-eight participants provided useable data. Bilateral uncinate fasciculus FA was significantly negatively associated with depressive symptoms at both waves (standardized β=0.12–0.16). Higher neuroticism and lower extraversion were also significantly associated with lower uncinate FA bilaterally (standardized β=0.09–0.15) and significantly mediated the relationship between FA and depressive symptoms.
Conclusions
Trait liability to depression and depressive symptoms are associated with reduced structural connectivity in tracts connecting the prefrontal cortex with the amygdala and anterior temporal cortex. These effects suggest that frontotemporal disconnection is linked to the etiology of depression, in part through personality trait differences.
Symptoms of anxiety and depression are common in older people, but the relative importance of factors operating in early and later life in influencing risk is unclear, particularly in the case of anxiety.
Method
We used data from five cohorts in the Healthy Ageing across the Life Course (HALCyon) collaborative research programme: the Aberdeen Birth Cohort 1936, the Caerphilly Prospective Study, the Hertfordshire Ageing Study, the Hertfordshire Cohort Study and the Lothian Birth Cohort 1921. We used logistic regression to examine the relationship between factors from early and later life and risk of anxiety or depression, defined as scores of 8 or more on the subscales of the Hospital Anxiety and Depression Scale, and meta-analysis to obtain an overall estimate of the effect of each.
Results
Greater neuroticism, poorer cognitive or physical function, greater disability and taking more medications were associated in cross-sectional analyses with an increased overall likelihood of anxiety or depression. Associations between lower social class, either in childhood or currently, history of heart disease, stroke or diabetes and increased risk of anxiety or depression were attenuated and no longer statistically significant after adjustment for potential confounding or mediating variables. There was no association between birth weight and anxiety or depression in later life.
Conclusions
Anxiety and depression in later life are both strongly linked to personality, cognitive and physical function, disability and state of health, measured concurrently. Possible mechanisms that might underlie these associations are discussed.
Previous studies have suggested a link between flavonoid intake and better cognitive function in later life but have not been able to control for possible confounding by prior intelligence quotient (IQ). The aim of the present study was to address this issue in a cross-sectional survey of 1091 men and women born in 1936, in whom IQ was measured at age 11 years. At the age of 70 years, participants carried out various neuropsychological tests and completed a FFQ. Associations between test scores and nutrient intake were assessed by linear regression with adjustment for potentially confounding variables. Total fruit, citrus fruits, apple and tea intakes were initially found to be associated with better scores in a variety of cognitive tests, but the associations were no longer statistically significant after adjusting for confounding factors, including childhood IQ. Flavanone intake was initially found to be associated with better scores in verbal fluency (P = 0·003, with standardised regression coefficient 0·10), but, again, the association was no longer statistically significant after adjusting for confounding factors. These findings do not support a role for flavonoids in the prevention of cognitive decline in later life. Studies of diet and cognitive function should include measurement of potential confounding variables, including prior IQ wherever possible.
Background: The Hospital Anxiety and Depression Scale (HADS) is widely used but evaluation of its psychometric properties has produced equivocal results. Little is known about its structure in non-clinical samples of older people.
Methods: We used data from four cohorts in the HALCyon collaborative research program into healthy aging: the Caerphilly Prospective Study, the Hertfordshire Ageing Study, the Hertfordshire Cohort Study, and the Lothian Birth Cohort 1921. We used exploratory factor analysis and confirmatory factor analysis with multi-group comparisons to establish the structure of the HADS and test for factorial invariance between samples.
Results: Exploratory factor analysis showed a bi-dimensional structure (anxiety and depression) of the scale in men and women in each cohort. We tested a hypothesized three-factor model but high correlations between two of the factors made a two-factor model more psychologically plausible. Multi-group confirmatory factor analysis revealed that the sizes of the respective item loadings on the two factors were effectively identical in men and women from the same cohort. There was more variation between cohorts, particularly those from different parts of the U.K. and in whom the HADS was administered differently. Differences in social-class distribution accounted for part of this variation.
Conclusions: Scoring the HADS as two subscales of anxiety and depression is appropriate in non-clinical populations of older men and women. However, there were differences between cohorts in the way that individual items were linked with the constructs of anxiety and depression, perhaps due to differences in sociocultural factors and/or in the administration of the scale.
For any integers $d,n \geq 2$, let $X \subset \mathbb{P}^{n}$ be a non-singular hypersurface of degree $d$ that is defined over the rational numbers. The main result in this paper is a proof that the number of rational points on $X$ which have height at most $B$ is $O(B^{n - 1 + \varepsilon})$, for any $\varepsilon > 0$. The implied constant in this estimate depends at most upon $d$, $\varepsilon$ and $n$.
The investigation described here is an experimental study directed toward determining flow field and surface friction characteristics of a cylindrical wall jet. The flow configuration is obtained by placing a cylindrical rod along the axis of a converging nozzle. The flow field thus produced consists of a developing turbulent boundary layer co-existing with an outer fluid layer that mixes freely with quiescent surroundings. Direct measurements of fluid friction at the rod surface, performed with a hot-film element, revealed a significant effect of transverse surface curvature on the local friction factor. Velocity profiles at various axial stations exhibited similarity in the outer mixing layer, but not in the boundary layer adjacent to the surface. Representations of the velocity field in terms of law of the wall variables and defect-law variables revealed significant transverse curvature effects. The measured wall-jet velocity profiles could be satisfactorily represented in terms of a law of the wake, wherein the wake function depends on a transverse curvature parameter. In the outer mixing layer, the eddy viscosity data correspond closely to those of free jets.