Early-life antibiotic use and subsequent diagnosis of food allergy and allergic diseases.

BACKGROUND: Antibiotic use in early life has been linked to disruptions in the microbiome. Such changes can disturb immune system development. Differences have been observed in the microbiota of children with and without allergies, but there have been few studies on antibiotic use and allergic disease. OBJECTIVE: We evaluated associations of early-life antibiotic use with subsequent occurrence of food allergy and other allergies in childhood using electronic health record data. METHODS: We used longitudinal data on 30 060 children up to age 7 years from Geisinger Clinic's electronic health record to conduct a sex- and age-matched case-control study to evaluate the association between antibiotic use and milk allergy, non-milk food allergies, and other allergies. For each outcome, we estimated conditional logistic regression models adjusting for race/ethnicity, history of Medical Assistance, and mode of birth delivery. Models were repeated separately for penicillins, cephalosporins and macrolides. RESULTS: There were 484 milk allergy cases, 598 non-milk food allergy cases and 3652 other allergy cases. Children with three or more antibiotic orders had a greater odds of milk allergy (Odds Ratio; 95% Confidence interval) (1.78; 1.28-2.48), non-milk food allergy (1.65; 1.27-2.14), and other allergies (3.07; 2.72-3.46) compared with children with no antibiotic orders. Associations were strongest at younger ages and differed by antibiotic class. CONCLUSIONS AND CLINICAL RELEVANCE: We observed associations between antibiotic orders and allergic diseases, providing evidence of a potentially modifiable clinical practice associated with paediatric allergic disease. Differences by antibiotic class should be further explored, as this knowledge could inform paediatric treatment decisions.

Antibiotic use and childhood body mass index trajectory.

BACKGROUND/OBJECTIVES: Antibiotics are commonly prescribed for children. Use of antibiotics early in life has been linked to weight gain but there are no large-scale, population-based, longitudinal studies of the full age range among mainly healthy children. SUBJECTS/METHODS: We used electronic health record data on 163 820 children aged 3-18 years and mixed effects linear regression to model associations of antibiotic orders with growth curve trajectories of annual body mass index (BMI) controlling for confounders. Models evaluated three kinds of antibiotic associations-reversible (time-varying indicator for an order in year before each BMI), persistent (time-varying cumulative orders up to BMIj) and progressive (cumulative orders up to prior BMI (BMIj-1))-and whether these varied by age. RESULTS: Among 142 824 children under care in the prior year, a reversible association was observed and this short-term BMI gain was modified by age (P<0.001); effect size peaked in mid-teen years. A persistent association was observed and this association was stronger with increasing age (P<0.001). The addition of the progressive association among children with at least three BMIs (n=79 752) revealed that higher cumulative orders were associated with progressive weight gain; this did not vary by age. Among children with an antibiotic order in the prior year and at least seven lifetime orders, antibiotics (all classes combined) were associated with an average weight gain of approximately 1.4 kg at age 15 years. When antibiotic classes were evaluated separately, the largest weight gain at 15 years was associated with macrolide use. CONCLUSIONS: We found evidence of reversible, persistent and progressive effects of antibiotic use on BMI trajectories, with different effects by age, among mainly healthy children. The results suggest that antibiotic use may influence weight gain throughout childhood and not just during the earliest years as has been the primary focus of most prior studies.

Sexual network position and risk of sexually transmitted infections.

OBJECTIVES: A population-based sexual network study was used to identify sexual network structures associated with sexually transmitted infection (STI) risk, and to evaluate the degree to which the use of network-level data furthers the understanding of STI risk. METHODS: Participants (n = 655) were from the baseline and 12-month follow-up waves of a 2001-2 population-based longitudinal study of sexual networks among urban African-American adolescents. Sexual network position was characterised as the interaction between degree (number of partners) and two-reach centrality (number of partners' partners), resulting in the following five positions: confirmed dyad, unconfirmed dyad, periphery of non-dyadic component, centre of star-like component and interior of non-star component. STI risk was measured as laboratory-confirmed infection with gonorrhoea and/or chlamydia. RESULTS: Results of logistic regression models with generalised estimating equations showed that being in the centre of a sexual network component increased the odds of infection at least sixfold compared with being in a confirmed dyad. Individuals on the periphery of non-dyadic components were nearly five times more likely to be infected than individuals in confirmed dyads, despite having only one partner. Measuring network position using only individual-based information led to twofold underestimates of the associations between STI risk and network position. CONCLUSIONS: These results demonstrate the importance of measuring sexual network structure using network data to fully capture the probability of exposure to an infected partner.

A new method for predicting recovery after stroke.

BACKGROUND AND PURPOSE: Several prognostic factors have been identified for outcome after stroke. However, there is a need for empirically derived models that can predict outcome and assist in medical management during rehabilitation. To be useful, these models should take into account early changes in recovery and individual patient characteristics. We present such a model and demonstrate its clinical utility. METHODS: Data on functional recovery (Barthel Index) at 0, 2, 4, 6, and 12 months after stroke were collected prospectively for 299 stroke patients at 2 London hospitals. Multilevel models were used to model recovery trajectories, allowing for day-to-day and between-patient variation. The predictive performance of the model was validated with an independent cohort of 710 stroke patients. RESULTS: Urinary incontinence, sex, prestroke disability, and dysarthria affected the level of outcome after stroke; age, dysphasia, and limb deficit also affected the rate of recovery. Applying this to the validation cohort, the average difference between predicted and observed Barthel Index was -0.4, with 90% limits of agreement from -7 to 6. Predicted Barthel Index lay within 3 points of the observed Barthel Index on 49% of occasions and improved to 69% when patients' recovery histories were taken into account. CONCLUSIONS: The model predicts recovery at various stages of rehabilitation in ways that could improve clinical decision making. Predictions can be altered in light of observed recovery. This model is a potentially useful tool for comparing individual patients with average recovery trajectories. Patients at elevated risk could be identified and interventions initiated.

A population-based perspective of changes in health-related quality of life after myocardial infarction in older men and women.

This study analyzes changes in health-related quality-of-life (HQL) outcomes following myocardial infarction (MI) from a population-based perspective. Data came from a representative sample of 2812 men and women 65 years and older living in New Haven, CT. All subjects were interviewed at baseline in 1982, and again in 1985 and 1988. HQL outcomes included self-rated health, depressive symptoms, and physical and social functioning. Pooled logistic regression models were used to estimate the risk for decline in HQL outcomes due to MI. Of the 203 MIs during follow-up, 111 (55%) survived until the next interview to provide post-MI data on outcomes. In bivariate analysis, MI patients were more likely than subjects without MI to show a decline in physical functioning (26.4% vs. 11.9%, P = .001) and social functioning (31.4% vs. 20.8%), P = .06). There were no differences in self-rated health (26.3% vs. 26.9%), but MI patients were less likely to show an increase in depression (9.1%) vs. 15.8%, P = .08). These associations remained mostly unchanged after adjustment for CHD risk factors. The effect of MI on physical and social functioning was much stronger among patients with a recent MI (<1 year ago) than those whose MI had occurred more than a year before post-MI assessment. While a substantial proportion of MI patients experience a significant decline in quality of life-related outcomes, only some of these declines occur more frequently among MI patients than in the population at large. This effect may also be limited to the immediate post-MI period. Results from this analysis are discussed in terms of the "burden of illness" within a defined population due to MI.

Driving cessation and increased depressive symptoms: prospective evidence from the New Haven EPESE. Established Populations for Epidemiologic Studies of the Elderly.

OBJECTIVES: The purpose of this study was to determine the association between driving cessation and depressive symptoms among older drivers. Previous efforts in this area have focused on the factors associated with cessation, not the consequences of having stopped. DESIGN: Cohort study. SETTING: Urban community. PARTICIPANTS: A driving survey was administered in 1989 to surviving noninstitutionalized members of the New Haven Established Populations for Epidemiologic Studies of the Elderly (EPESE) cohort. Of 1316 respondents, 502 were active drivers as of 1988, 92 had stopped driving between 1982 and 1987, and the remainder had either never driven or had stopped before 1982. MEASUREMENTS: Information about independent and dependent variables other than driving status came from the in person EPESE interviews in 1982, 1985, and 1988, except for medical conditions, which were updated yearly. Depressive symptoms were assessed by the Centers for Epidemiologic Studies-Depression (CES-D) scale. Analyses focused on the changes in depressive symptoms before and after driving cessation. Repeated measures multivariable analysis accounted for the effect of cessation on the outcome adjusting for the potential confounding due to sociodemographic and health-related factors. RESULTS: Individuals who stopped driving exhibited substantial increases in depressive symptoms during the 6-year interval. Driving cessation was among the strongest predictors of increased depressive symptoms (Coefficient 2.464, SE 0.758, P = .001) even when adjusting for sociodemographic and health-related factors. CONCLUSIONS: Driving cessation was associated with an increase in depressive symptoms even when accounting for sociodemographic and health-related factors. These consequences need to be taken into account when advising older drivers and when developing alternative transportation strategies.

The quality and quantity of social support: stroke recovery as psycho-social transition.

The impact of various types and amounts of social support is examined in the context of recovery from first stroke. We conceptualize the rehabilitation process as a psychosocial transition. In a longitudinal design, 44 patients were followed for 6 months following first stroke. Growth-curve analysis (repeated measures MANOVA) was utilized to examine the impact of three types of social support on changes in functional status during recovery. While all three types of support (emotional, instrumental and informational) were shown to be significantly related to recovery of functional capacity, substantial differences were found in the nature of those effects. The impact of social support does not appear during the first month of rehabilitation, indicating the importance of longitudinal designs and longer observation. Patients reporting high level of emotional support showed dramatic improvement despite having the lowest baseline functional status. Instrumental support is most closely related to positive outcomes when provided in moderate amounts. Unlike the other two types, the effect of informational support is mediated by disease severity.

Beyond single indicators of social networks: a LISREL analysis of social ties among the elderly.

While the health promoting influences of social networks have been shown in a number of studies, little attention has been paid to measurement issues within the field of epidemiology. The purpose of this paper is to propose a new set of measures of social networks for use in epidemiological research on the elderly. We use confirmatory factor analysis to test a multidimensional model of social networks using data from a large epidemiologic study of community-dwelling adults age 65 and over (U.S.A.). Confirmatory factor analysis conducted using LISREL showed that our model provides a good fit to the data after several adjustments for correlated measurement error were introduced. Based on this analysis, we developed new measures of four dimensions and a summary index of social networks. Bivariate relationships between our new measures and several sociodemographic variables of interest are also presented.

Conjugating the "tenses" of function: discordance among hypothetical, experimental, and enacted function in older adults.

Within the field of aging, the conceptualization and measurement of functioning has been dominated by the disability model. In this paper, one limitation of that model is described by calling attention to a distinction between three "tenses" of functioning. Inadequate attention has been paid to the distinction between the capacity to function in the abstract (hypothetical tense) and actual performance in daily life (enacted tense). Failure to attend to this distinction has obscured considerable discordance between what people say they are able to do in standard functional disability assessments, and what they actually do at home. To illustrate this point, data from the MacArthur Studies of Successful Aging comparing the hypothetical to the enacted tenses are presented. These data show a consistent pattern of discordance between these two tenses.

Change in productive activity in late adulthood: MacArthur studies of successful aging.

Both cross-sectional comparisons and patterns of change in productive activities among members of the MacArthur Successful Aging cohort were examined. The data came from a three-site longitudinal study of community-dwelling adults aged 70-79. The highest functioning cohort (n = 1,192) was found to be significantly more productive than a comparison group of medium- and low-functioning respondents at baseline in four of five domains examined. In longitudinal models, we tested several hypotheses regarding the determinants of change in levels of productive activity over a three-year period. Overall, 15.1 percent (n = 162) of the cohort became less productive, while another 12.7 percent (n = 136) became more productive. Risk factors for decline in productivity included hospital admission and stroke. Age, functional disability, marriage, and increased mastery were protective against declines. Conversely, Blacks, those who were more satisfied with life at baseline, and those reporting increased mastery were more likely to increase their productivity.

The effects of negative life events on alcohol consumption among older men and women.

We examined the effect of selected negative life events on changes in alcohol consumption in a prospective cohort study of community-dwelling persons 65 years of age and older. Using the Tension Reduction Hypothesis (TRH) as a framework, we tested the hypothesis that exposure to negative life events leads to increased alcohol consumption at follow-up (1985) after controlling for baseline alcohol consumption (1982) and covariates found to be associated with alcohol use. In addition, we modeled the interaction between exposure to events and baseline alcohol consumption. Among men, four of the eleven events tested were associated with higher alcohol consumption but only as interaction effects. Another two events were associated with decreased alcohol consumption. Among women, four significant interaction effects and two main effects were found in the expected direction. Two additional events were found to be associated with decreased drinking at follow-up. In general, alcohol consumption declined in the aggregate over the three-year period. Implications for the TRH are discussed.

Disability as a function of social networks and support in elderly African Americans and Whites: the Duke EPESE 1986--1992.

OBJECTIVES: We examined the association of structural and functional aspects of social relationships with change in disability, and the degree to which race modifies these associations. METHODS: Data are from a population-based sample of 4,136 African Americans and Whites aged > or = 65 living in North CAROLINA: Disability data were collected during seven consecutive yearly interviews and summarized in two outcome measures. Measures of social relationships included five measures representing network size, extent of social interaction, and specific type of relationships, as well as instrumental and emotional support. Weighted proportional odds models were fitted to model disability as a function of baseline social network and support variables, and the interaction of each variable with follow-up time. RESULTS: Network size and social interaction showed significant negative associations with disability risks, which did not vary by race, or as a function of time. Social interaction with friends was associated with a reduced risk for disability, but social interaction with children or relatives was not related to disability. Instrumental support was associated with a significantly increased disability risk, with a greater adverse effect among Whites than African AMERICANS: Emotional support was not associated with disability, but a protective effect for ADL disability was found after controlling for its intercorrelation with instrumental support. DISCUSSION: The findings provide further evidence for the role of social relationships in the disablement process, although not all types of social relationships may be equally beneficial. Furthermore, these associations may be more complex than simple causal effects. There were few racial differences in the association of social relationships with disability, with the possible exception of instrumental support, which may allude to possible sociocultural differences in the experience of instrumental support exchanges.

Consequences of driving cessation: decreased out-of-home activity levels.

OBJECTIVES: Increasing age, socioeconomic factors, and declining function and health have been linked to driving cessation, but little is known about the consequences of stopping driving. This study was designed to test the hypothesis that driving cessation leads to a decline in out-of-home activity levels. METHODS: In 1989 a survey of driving practices was administered to surviving noninstitutionalized members of the New Haven Established Populations for Epidemiologic Studies of the Elderly (EPESE) cohort. Of 1,316 respondents, 502 were active drivers as of 1988, 92 had stopped driving between 1982 and 1987, and 722 never drove or stopped before 1982. Information on sociodemographic and health-related variables came from in-home EPESE interviews in 1982, 1985, and 1988, and from yearly phone interviews. Activity was measured at all three in-home interviews, and an activity measure was created based on self-reported participation in nine out-of-home activities. A repeated measures random-effects model was used to test the effect of driving cessation on activity while controlling for potential confounders. RESULTS: Driving cessation was strongly associated with decreased out-of-home activity levels (coefficient-1.081, standard error 0.264, p < .001) after adjustment for sociodemographic and health-related factors. DISCUSSION: The potential consequences of driving limitations or cessation should be taken into account when advising older drivers and developing alternative transportation strategies to help maintain their mobility.

Social networks and disability transitions across eight intervals of yearly data in the New Haven EPESE.

OBJECTIVES: There is considerable evidence that social networks are strongly related to survival and other health outcomes. However, findings regarding the effect of social networks on disability outcomes have been inconsistent. This study examines this relationship with respect to the risk of developing disability and recovering from disability. METHODS: Data come from a community-based sample of the New Haven population aged 65 years and older, with nine annual interviews conducted between 1982 and 1991. Disability was measured by a 6-item index of activities of daily living (ADL), and a 3-item Rosow-Breslau index, with disability defined as impairment in one or more tasks on each measure. Social network variables were constructed for each of four domains of ties: children, relatives, friends, and a confidant, and a summary measure of total social networks. A Markov model was used to estimate one-year disability transitions averaged across all 8 intervals, after controlling for sociodemographic and health-related variables. RESULTS: Total social networks was associated with a significantly reduced risk of developing ADL disability (beta = -0.009, p < .01), and a significantly increased likelihood of ADL recovery (beta = 0.017, p < .01). Emotional and instrumental support did not affect the protective effect of social networks against disability, but partially accounted for their effect on enhanced recovery. Network variables related to relatives and friends were significantly associated with disability and recovery risks, but those related to children or a confidant were not. The associations with disability transitions as measured by the Rosow-Breslau index were generally smaller and nonsignificant. DISCUSSION: The findings lend further support for the role of social relationships in important health outcomes in old age. They suggest that being "embedded" in a social network of relatives and friends reduces risk for ADL disability, and enhances recovery from ADL disability.

Stressful life events and depressive symptoms among the elderly. Evidence from a prospective community study.

We examined the effect of a series of common stressful life events on change in depressive symptoms among the elderly. The subjects were 1,962 noninstitutionalized people 65 years of age or older from the New Haven EPESE project. Multivariate regression models revealed that 8 of 11 stressful life events examined predicted change in depressive symptoms at follow-up (1985) after controlling for baseline depressive symptoms age, socioeconomic factors, functional status, and chronic conditions. In addition, the total number of stressful life events was significantly associated with higher CES-D depression scores. A dose-response relationship between cumulative life event stress and change in depressive symptoms was also shown. These results suggest that certain common life event stressors may have an impact on mental health, both singly and in combination.

Psychosocial intervention in stroke: Families in Recovery from Stroke Trial (FIRST).

A family-focused psychosocial intervention for stroke survivors is described and illustrated with case studies. It is designed to improve functional recovery through four specific pathways: increased knowledge, efficacy, and control through stroke education; optimized social support; increased network cohesion; and improved problem-solving abilities. Rationales for these pathways are presented and methods of implementing them discussed.

Population based study of social and productive activities as predictors of survival among elderly Americans.

OBJECTIVES: To examine any association between social, productive, and physical activity and 13 year survival in older people. DESIGN: Prospective cohort study with annual mortality follow up. Activity and other measures were assessed by structured interviews at baseline in the participants' homes. Proportional hazards models were used to model survival from time of initial interview. SETTING: City of New Haven, Connecticut, United States. PARTICIPANTS: 2761 men and women from a random population sample of 2812 people aged 65 and older. MAIN OUTCOME MEASURE: Mortality from all causes during 13 years of follow up. RESULTS: All three types of activity were independently associated with survival after age, sex, race/ethnicity, marital status, income, body mass index, smoking, functional disability, and history of cancer, diabetes, stroke, and myocardial infarction were controlled for. CONCLUSIONS: Social and productive activities that involve little or no enhancement of fitness lower the risk of all cause mortality as much as fitness activities do. This suggests that in addition to increased cardiopulmonary fitness, activity may confer survival benefits through psychosocial pathways. Social and productive activities that require less physical exertion may complement exercise programmes and may constitute alternative interventions for frail elderly people.