Mixed-Methods Study of Disability Self-Management in Mexican Americans With Osteoarthritis

BACKGROUND

Health disparities in osteoarthritis (OA) outcomes exist both in the occurrence and treatment of functional limitation and disability for Mexican Americans. Although the effect of self-management of chronic illness is well established, studies demonstrate little attention to self-management of function or disability, despite the strong potential effect on both and, consequently, on patients' lives.

OBJECTIVE

The purpose of this study pilot was to develop and test key variable relationships for a measure of disability self-management among Mexican Americans.

METHODS

In this sequential, two-phased, mixed-methods, biobehavioral pilot study of Mexican American women and men with OA, a culturally tailored measure of disability self-management was created, and initial relationships among key variables were explored.

RESULTS

First, a qualitative study of 19 adults of Mexican American descent born in Texas (United States) or Mexico was conducted. The Mexican American Disability Self-Management Scale was created using a descriptive content analysis of interview data. The scale was tested and refined, resulting in 18 items and a descriptive frequency of therapeutic management efforts. Second, correlations between study variables were estimated: Disability and function were negatively correlated. Disability correlated positively with social support and activity effort. Disability correlated negatively with disability self-management, pain, and C-reactive protein. Function was positively correlated with age, pain, and depression. Liver enzymes (alanine transaminase) correlated positively with pain and anxiety.

DISCUSSION

This mixed-methods study indicates directions for further testing and interventions for disability outcomes among Mexican Americans.

First-interview response patterns of intensive longitudinal psychological and health data

Self-report data are essential in health psychology research where an individual's perception is critical to understanding one's health and psychological status. Intensive data collection over time, including daily diary assessments, is necessary in understanding within- and between-person variability in health and psychological processes over time. An "initial elevation or latent decline" (IELD) effect, inherent of self-report data, is increasingly acknowledged in the social psychology literature, but awareness of this effect in health psychology research is lacking, particularly in studies that emphasize within- and between-person variability in self-reports. The IELD effect is a pattern in which responses tend to be more extreme at the initial interview relative to subsequent responses. This paper illustrates the impact of IELD in applications of mixed-effects models based on observational self-reports and concludes that researchers take such effects into account in data analysis or in the research designing phase to help mitigate such effects.

Bayesian pattern-mixture models for dropout and intermittently missing data in longitudinal data analysis

Valid inference can be drawn from a random-effects model for repeated measures that are incomplete if whether the data are missing or not, known as missingness, is independent of the missing data. Data that are missing completely at random or missing at random are two data types for which missingness is ignorable. Given ignorable missingness, statistical inference can proceed without addressing the source of the missing data in the model. If the missingness is not ignorable, however, recommendations are to fit multiple models that represent different plausible explanations of the missing data. A popular choice in methods for evaluating nonignorable missingness is a random-effects pattern-mixture model that extends a random-effects model to include one or more between-subjects variables that represent fixed patterns of missing data. Generally straightforward to implement, a fixed pattern-mixture model is one among several options for assessing nonignorable missingness, and when it is used as the sole model to address nonignorable missingness, understanding the impact of missingness is greatly limited. This paper considers alternatives to a fixed pattern-mixture model for nonignorable missingness that are generally straightforward to fit and encourage researchers to give greater attention to the possible impact of nonignorable missingness in longitudinal data analysis. Patterns of both monotonic and non-monotonic (intermittently) missing data are addressed. Empirical longitudinal psychiatric data are used to illustrate the models. A small Monte Carlo data simulation study is presented to help illustrate the utility of such methods.

Alternative covariance structures in mixed-effects models: Addressing intra- and inter-individual heterogeneity

Mixed-effects models for repeated measures and longitudinal data include random coefficients that are unique to the individual, and thus permit subject-specific growth trajectories, as well as direct study of how the coefficients of a growth function vary as a function of covariates. Although applications of these models often assume homogeneity of the within-subject residual variance that characterizes within-person variation after accounting for systematic change and the variances of the random coefficients of a growth model that quantify individual differences in aspects of change, alternative covariance structures can be considered. These include allowing for serial correlations between the within-subject residuals to account for dependencies in data that remain after fitting a particular growth model or specifying the within-subject residual variance to be a function of covariates or a random subject effect to address between-subject heterogeneity due to unmeasured influences. Further, the variances of the random coefficients can be functions of covariates to relax the assumption that these variances are constant across subjects and to allow for the study of determinants of these sources of variation. In this paper, we consider combinations of these structures that permit flexibility in how mixed-effects models are specified to understand within- and between-subject variation in repeated measures and longitudinal data. Data from three learning studies are analyzed using these different specifications of mixed-effects models.

A latent variable mixed-effects location scale model that also considers between-person differences in the autocorrelation

In public health research an increasing number of studies is conducted in which intensive longitudinal data is collected in an experience sampling or a daily diary design. Typically, the resulting data is analyzed with a mixed-effects model or mixed-effects location scale model because they allow one to examine a host of interesting longitudinal research questions. Here, we introduce an extension of the mixed-effects location scale model in which measurement error of the observed variables is considered by a latent factor model and in which-in addition to the mean-or location-related effects-the residual variance of the latent factor and the parameters of the autoregressive process of this latent factor can differ between persons. We show how to estimate the parameters of the model with a maximum likelihood approach, whose performance is also compared with a Bayesian approach in a small simulation study. We illustrate the models using a real data example and end with a discussion in which we suggest questions for future research.

Longitudinal Effects of Sex, Aging, and Multiple Sclerosis Diagnosis on Function

BACKGROUND

A gap in research about the trajectories of function among men and women aging with functional limitations because of multiple sclerosis (MS) hinders ability to plan for future needs.

OBJECTIVES

Using a biopsychosocial model, we characterize how men and women with MS report changes over time in their function and test how person-level differences in age, diagnosis duration, and sex influence perceived function.

METHODS

A longitudinal study with multiple waves of surveys was used to collect data on participant perceptions of function, as well as demographic and contextual variables. Self-reported functional limitation was measured over a decade. The study participants were community residing with physician-diagnosed MS.

RESULTS

The people with MS had a diagnosis duration of about 13 years and were around 51 years of age, on average, at the start of the study. They were primarily women and non-Hispanic White. We analyzed the data using mixed-effects models. Subject-specific, functional limitation trajectories were described best with a quadratic growth model. Relative to men, women reported lower functional limitation and greater between-person variation and rates of acceleration in functional limitation scores.

DISCUSSION

Results suggest function progressed through two pathways for over a decade, particularly closer to diagnoses. Variability in trajectories between individuals based on sex and years since diagnosis of disease indicates that men and women with MS may experience perceptions of their function with age differently. This has implications for clinician advice to men and women with MS.

A Latent Variable Mixed-Effects Location Scale Model with an Application to Daily Diary Data

A mixed-effects location scale model allows researchers to study within- and between-person variation in repeated measures. Key components of the model include separate variance models to study predictors of the within-person variance, as well as predictors of the between-person variance of a random effect, such as a random intercept. In this paper, a latent variable mixed-effects location scale model is developed that combines a longitudinal common factor model and a mixed-effects location scale model to characterize within- and between-person variation in a common factor. The model is illustrated using daily reports of positive affect and daily stressors for a large sample of adult women.

Predicting romantic interest during early relationship development: A preregistered investigation using machine learning

There are massive literatures on initial attraction and established relationships. But few studies capture early relationship development: the interstitial period in which people experience rising and falling romantic interest for partners who could—but often do not—become sexual or dating partners. In this study, 208 single participants reported on 1,065 potential romantic partners across 7,179 data points over 7 months. In stage 1, we used random forests (a type of machine learning) to estimate how well different classes of variables (e.g., individual differences vs. target-specific constructs) predicted participants’ romantic interest in these potential partners. We also tested (and found only modest support for) the perceiver × target moderation account of compatibility: the meta-theoretical perspective that some types of perceivers experience greater romantic interest for some types of targets. In stage 2, we used multilevel modeling to depict predictors retained by the random-forests models; robust (positive) main effects emerged for many variables, including sociosexuality, sex drive, perceptions of the partner’s positive attributes (e.g., attractive and exciting), attachment features (e.g., proximity seeking), and perceived interest. Finally, we found no support for ideal partner preference-matching effects on romantic interest. The discussion highlights the need for new models to explain the origin of romantic compatibility.

Music Compared with Auditory Books: A Randomized Controlled Study Among Long-Term Care Residents with Alzheimer's Disease or Related Dementia

BACKGROUND

Over 5 million Americans age 65 years and older were diagnosed with Alzheimer's disease and/or related dementia (ADRD), a majority of whom exhibit behavioral and psychological symptoms leading to placement in long-term care settings. These facilities need nonmedical interventions, and music-based programs have received supportive evidence.

SETTING

Thirteen long-term care facilities were among a wave of facilities that volunteered to be trained and to administer a music-based intervention. The residents within were randomized into intervention or control groups (intervention/music, n = 103; control/audiobook, n = 55).

DESIGN

This team used a pragmatic trial to randomly embed music and control (audiobooks) into 13 long-term care facilities to compare the effects on agitation in people with ADRD.

METHODS

Measures included a demographic survey; the Mini-Mental Status Examination, used to assess cognitive status; and the Cohen-Mansfield Agitation Inventory with 4 subscales, used to measure agitation. These measures were implemented at baseline and every 2 weeks for 8 weeks. Mixed-effects models were used to evaluate change in agitation measures while addressing dependencies of scores within participants and facility.

RESULTS

Decreases in agitation were attributable to both music and audiobooks in 3 of 4 agitation subscales. In the fourth, physical agitation, which was not directed toward staff, initially, it decreased given music, and increased thereafter; and generally, it increased with the audiobooks.

CONCLUSION AND IMPLICATIONS

Both music and control audiobooks delivered by headphones after personalized selection reduced some aspects of agitation in residents diagnosed with ADRD. The effects of music were greater initially then diminished.

A new look at neurobehavioral development in rhesus monkey neonates (Macaca mulatta)

The Brazelton Neonatal Behavioral Assessment Scale (NBAS) evaluates a newborn infant's autonomic, motor, state, temperament, and social-attentional systems, which can help to identify infants at risk of developmental problems. Given the prevalence of rhesus monkeys being used as an animal model for human development, here we aimed to validate a standardized test battery modeled after the NBAS for use with nonhuman primates called the Infant Behavioral Assessment Scale (IBAS), employing exploratory structural equation modeling using a large sample of rhesus macaque neonates (n = 1,056). Furthermore, we examined the repeated assessments of the common factors within the same infants to describe any changes in performance over time, taking into account two independent variables (infant sex and rearing condition) that can potentially affect developmental outcomes. Results revealed three factors (Orientation, State Control, and Motor Activity) that all increased over the 1st month of life. While infant sex did not have an effect on any factor, nursery-rearing led to higher scores on Orientation but lower scores on State Control and Motor Activity. These results validate the IBAS as a reliable and valuable research tool for use with rhesus macaque infants and suggest that differences in rearing conditions can affect developmental trajectories and potentially pre-expose infants to heightened levels of cognitive and emotional deficiencies.

A Capabilities Approach to Environmental Impact on Nursing Home Resident Quality of Life

Nursing homes are the major provider of intermediate and long-term care outside of the hospital setting to individuals whose capacity for self-care is limited due to physical or cognitive impairments. Yet, despite their need for assistance, residents of nursing homes want to control their lives, set their routines, and do enjoyable things. The extent to which residents can maintain autonomy and dignity is important. The current study suggests an environmental gerontological framework, rooted in a capabilities approach, that can be used to consider environmental impact on quality of life in nursing homes. Using a cross-sectional survey of nursing home residents in Texas, environmental factors that might predict residents' quality of life as well as possible interactions of environmental factors and residents' characteristics that might predict well-being were examined. Environmental orientation and perception of social activities were important predictors of residents' quality of life, but geographic location and facility size were not important predictors. [Res Gerontol Nurs. 2017; 10(4):162-170.].

Cognitive reappraisal and expressive suppression: Links to racial-ethnic discrimination and adjustment among Latino/a and Asian-heritage college students

OBJECTIVE

We examined whether two key emotion regulation strategies, cognitive reappraisal and expressive suppression, moderated the relations between discrimination (i.e., foreigner objectification and general denigration) and adjustment.

METHODS

Participants were U.S. Latino/a and Asian-heritage college students (N = 1,279, 67% female, 72% U.S. born) from the Multi-Site University Study of Identity and Culture (MUSIC). Students completed online self-report surveys in 2009.

RESULTS

Multi-group path analysis demonstrated that a fully constrained model fit well for both Latino/a and Asian-heritage student data. The results showed that with increasing levels of denigration (but not foreigner objectification), the combination of lower cognitive reappraisal and higher expressive suppression was related to greater depressive symptoms, anxiety, and aggression.

CONCLUSIONS

Our findings highlight the importance of examining multiple emotion regulation strategies simultaneously-considering what strategies are available to individuals and in what combination they are used-to understand how best to deal with negative emotions resulting from experiencing discrimination.

Health Beliefs of Mexican Americans With Type 2 Diabetes

PURPOSE

The purpose of this study was to compare 2 culturally competent diabetes self-management interventions designed for Mexican Americans: an original extended program (24 hours of education, 28 hours of support groups) versus a shorter, more resource-efficient compressed strategy (16 hours of education, 6 hours of support groups). The effects of the interventions on health beliefs are compared.

METHODS

The authors recruited 216 persons between 35 and 70 years of age diagnosed with type 2 diabetes for at least 1 year. Intervention groups of 8 participants and 8 support persons were randomly assigned to 1 of the interventions.

RESULTS

Mean health belief scores on each subscale improved for both intervention groups. Both intervention groups reported significant improvements in perceptions of control of their diabetes. Improvements in health beliefs were more sustained at 12 months for individuals in the longer, extended program. The health belief subscale control was the most significant predictor of HbA1c levels at 12 months.

CONCLUSIONS

Both culturally competent diabetes self-management education interventions were effective in promoting more positive health beliefs. These findings on health beliefs indicate a dosage effect of the intervention and support the importance of ongoing contact through support groups to attain more sustainable improvements in health beliefs.

A Note on Recurring Misconceptions When Fitting Nonlinear Mixed Models

Nonlinear mixed-effects (NLME) models are used when analyzing continuous repeated measures data taken on each of a number of individuals where the focus is on characteristics of complex, nonlinear individual change. Challenges with fitting NLME models and interpreting analytic results have been well documented in the statistical literature. However, parameter estimates as well as fitted functions from NLME analyses in recent articles have been misinterpreted, suggesting the need for clarification of these issues before these misconceptions become fact. These misconceptions arise from the choice of popular estimation algorithms, namely, the first-order linearization method (FO) and Gaussian-Hermite quadrature (GHQ) methods, and how these choices necessarily lead to population-average (PA) or subject-specific (SS) interpretations of model parameters, respectively. These estimation approaches also affect the fitted function for the typical individual, the lack-of-fit of individuals' predicted trajectories, and vice versa.

Factorial Invariance of a Pan-Hispanic Familism Scale

This article considers the validity and factorial invariance of an attitudinal measure of familism. Using a large, nationally representative sample of U.S. Hispanics, the validity and factorial invariance of the measure was tested across country of origin (United States, Mexico, and Latin America) and the language in which the survey was conducted (Spanish and English). Results support the invariance of the measure in both group comparisons, suggesting that the measure assesses a quality of familism that persists across country of origin and language preference. Further, the results also support equality in mean factor levels across these groups.

Nonlinear latent curve models for multivariate longitudinal data

Latent curve models have become a useful approach to analyzing longitudinal data, due in part to their allowance of and emphasis on individual differences in features that describe change. Common applications of latent curve models in developmental studies rely on polynomial functions, such as linear or quadratic functions. Although useful for describing linear forms of change and some that are nonlinear, latent curve models based on polynomial functions are not suitable for describing many developmental processes that change in a nonlinear manner. This article considers nonlinear latent curve models that permit researchers to consider a variety of nonlinear functions to characterize developmental processes. An example is provided that considers simultaneous development of two behaviors.

Do "birds of a feather flock together" or do "opposites attract"? Behavioral responses and temperament predict success in pairings of rhesus monkeys in a laboratory setting

The growing recognition that social needs of primates in captivity must be addressed can present challenges to staff at primate facilities charged with implementing pair-housing solutions for animals. Unfortunately, there are few published papers that identify individual characteristics that might facilitate the social pairing process, and those that have looked at pre-pairing measures of behavior have produced mixed results. Using a database of n = 340 isosexual pairing attempts, we report that measures associated with responses to a standardized infant assessment protocol (the BioBehavioral Assessment program) predict success in pairing attempts that occurred years later. Behavioral responses to a brief separation and relocation, to a human intruder challenge, as well as ratings of temperament, were obtained from rhesus monkeys at 3-4 months of age. Logistic regression was used to identify potential predictors of success when animals were paired up to 10 years after the behavioral assessments. Among females, success was higher when members of a pair were more similar (i.e., a smaller difference scores) in patterns of emotional responding (Emotionality, Nervous temperament) during the infant assessments. In contrast, among males, success was higher when the pair had lower mean values for Gentle and Nervous temperament scores; when the members were younger; when pairs had a greater weight difference; and when they came from the same rearing background. Together, our results suggest that broad measures reflecting patterns of emotionality in response to challenge, which can be assessed in infancy (but which remain relatively stable throughout life) can be usefully employed to increase the likelihood of success in pairing attempts. Am. J. Primatol. 79:e22464, 2017. © 2015 Wiley Periodicals, Inc.

Overcoming Clinical Inertia: A Randomized Clinical Trial of a Telehealth Remote Monitoring Intervention Using Paired Glucose Testing in Adults With Type 2 Diabetes

Background

Type 2 diabetes mellitus is a worldwide challenge. Practice guidelines promote structured self-monitoring of blood glucose (SMBG) for informing health care providers about glycemic control and providing patient feedback to increase knowledge, self-efficacy, and behavior change. Paired glucose testing—pairs of glucose results obtained before and after a meal or physical activity—is a method of structured SMBG. However, frequent access to glucose data to interpret values and recommend actions is challenging. A complete feedback loop—data collection and interpretation combined with feedback to modify treatment—has been associated with improved outcomes, yet there remains limited integration of SMBG feedback in diabetes management. Incorporating telehealth remote monitoring and asynchronous electronic health record (EHR) feedback from certified diabetes educators (CDEs)—specialists in glucose pattern management—employ the complete feedback loop to improve outcomes.

Objective

The purpose of this study was to evaluate a telehealth remote monitoring intervention using paired glucose testing and asynchronous data analysis in adults with type 2 diabetes. The primary aim was change in glycated hemoglobin (A_1c)—a measure of overall glucose management—between groups after 6 months. The secondary aims were change in self-reported Summary of Diabetes Self-Care Activities (SDSCA), Diabetes Empowerment Scale, and Diabetes Knowledge Test.

Methods

A 2-group randomized clinical trial was conducted comparing usual care to telehealth remote monitoring with paired glucose testing and asynchronous virtual visits. Participants were aged 30-70 years, not using insulin with A_1c levels between 7.5% and 10.9% (58-96 mmol/mol). The telehealth remote monitoring tablet computer transmitted glucose data and facilitated a complete feedback loop to educate participants, analyze actionable glucose data, and provide feedback. Data from paired glucose testing were analyzed asynchronously using computer-assisted pattern analysis and were shared with patients via the EHR weekly. CDEs called participants monthly to discuss paired glucose testing trends and treatment changes. Separate mixed-effects models were used to analyze data.

Results

Participants (N=90) were primarily white (64%, 56/87), mean age 58 (SD 11) years, mean body mass index 34.1 (SD 6.7) kg/m2, with diabetes for mean 8.2 (SD 5.4) years, and a mean A_1c of 8.3% (SD 1.1; 67 mmol/mol). Both groups lowered A_1c with an estimated average decrease of 0.70 percentage points in usual care group and 1.11 percentage points in the treatment group with a significant difference of 0.41 percentage points at 6 months (SE 0.08, t₁₅₉=–2.87, P=.005). Change in medication (SE 0.21, t₁₅₇=–3.37, P=.009) was significantly associated with lower A_1c level. The treatment group significantly improved on the SDSCA subscales carbohydrate spacing (P=.04), monitoring glucose (P=.001), and foot care (P=.02).

Conclusions

An eHealth model incorporating a complete feedback loop with telehealth remote monitoring and paired glucose testing with asynchronous data analysis significantly improved A_1c levels compared to usual care.

Trial Registration

Clinicaltrials.gov NCT01715649; https://www.clinicaltrials.gov/ct2/show/NCT01715649 (Archived by WebCite at http://www.webcitation.org/6ZinLl8D0).

On Fitting a Multivariate Two-Part Latent Growth Model

A 2-part latent growth model can be used to analyze semicontinuous data to simultaneously study change in the probability that an individual engages in a behavior, and if engaged, change in the behavior. This article uses a Monte Carlo (MC) integration algorithm to study the interrelationships between the growth factors of 2 variables measured longitudinally where each variable can follow a 2-part latent growth model. A SAS macro implementing Mplus is developed to estimate the model to take into account the sampling uncertainty of this simulation-based computational approach. A sample of time-use data is used to show how maximum likelihood estimates can be obtained using a rectangular numerical integration method and an MC integration method.

Sensitivity Analysis of Multiple Informant Models When Data are Not Missing at Random

Missing data are common in studies that rely on multiple informant data to evaluate relationships among variables for distinguishable individuals clustered within groups. Estimation of structural equation models using raw data allows for incomplete data, and so all groups may be retained even if only one member of a group contributes data. Statistical inference is based on the assumption that data are missing completely at random or missing at random. Importantly, whether or not data are missing is assumed to be independent of the missing data. A saturated correlates model that incorporates correlates of the missingness or the missing data into an analysis and multiple imputation that may also use such correlates offer advantages over the standard implementation of SEM when data are not missing at random because these approaches may result in a data analysis problem for which the missingness is ignorable. This paper considers these approaches in an analysis of family data to assess the sensitivity of parameter estimates to assumptions about missing data, a strategy that may be easily implemented using SEM software.

The effects of birth timing and ambient temperature on the hypothalamic-pituitary-adrenal axis in 3-4 month old rhesus monkeys

Birth timing, a relative measure of the timing of births within a season, has been shown to be related to the ways mothers and infant interact as well as to infant behavior and physiology. Although effects of birth timing on the hypothalamic-pituitary-adrenal (HPA) axis have previously been associated with variation in social relationships, these effects could also be related to seasonal variation in climate conditions when the birth season is long. The current study examines the effects of birth timing and ambient temperature on the activity and regulation of the HPA axis in 3-4 month old rhesus monkeys (N=338). Subjects were part of a BioBehavioral Assessment in which infants were separated from their mothers and relocated to a novel testing environment for a period of 25h. Four blood samples were collected and assayed for cortisol concentrations and reflected HPA response to (1) 2h maternal separation and relocation, (2) 7h maternal separation and relocation (sustained challenge), (3) dexamethasone suppression, and (4) ACTH challenge. Nonlinear mixed modeling was used to examine the independent effects of birth timing and temperature on HPA axis activity and regulation over the study period. Results indicated that birth timing and ambient temperature both had significant, but opposing effects on the cortisol response to sustained challenge. Chronic exposure to low ambient temperatures was associated with higher cortisol levels. After controlling for the effect of ambient temperature, birth timing was positively associated with cortisol such that late-born infants exhibited higher cortisol concentrations than did early-born infants. These results highlight the fact that climate conditions, even mild, subtropical conditions, can have potentially important influences on the activity and development of the HPA axis.

Client predictors of short-term psychotherapy outcomes among Asian and white American outpatients

PURPOSE

To examine predictors of psychotherapy outcomes, focusing on client characteristics that are especially salient for culturally diverse clients.

METHOD

Sixty clients (31 women; 27 White Americans, 33 Asian Americans) participated in this treatment study. Client characteristics were measured at pretreatment, and outcomes were measured postfourth session via therapist ratings of functioning and symptomatology. Regression analyses were utilized to test for predictors of outcomes, and bootstrap analyses were utilized to test for mediators.

RESULTS

Higher levels of somatic symptoms predicted lower psychosocial functioning at posttreatment. Avoidant coping style predicted more negative symptoms and more psychological discomfort. Non-English language preference predicted worse outcomes; this effect was mediated by an avoidant coping style.

CONCLUSIONS

Language preference, avoidant coping style, and somatic symptoms predicted treatment outcome in a culturally diverse sample. Findings suggest that race/ethnicity-related variables may function through mediating proximal variables to affect outcomes.

Behavioral effects of prenatal ketamine exposure in rhesus macaques are dependent on MAOA genotype

Ketamine is an N-methyl-D-aspartate (NMDA) receptor antagonist that is used in anesthetic, abuse, and therapeutic contexts. Recent evidence suggests that ketamine may affect not only glutamate systems, but may also act on receptors in the dopamine and serotonin systems. Because monoamine neurotransmitters play important trophic roles in prenatal development, we hypothesized that the behavioral consequences of prenatal exposure to ketamine may be moderated by genotype of the promoter in the monoamine oxidase-A (MAOA) gene. Eighty-two infant rhesus monkeys were identified that had known dates of conception and exposures to ketamine during gestation. Animals were tested at 3-4 months of age on a battery of tests assessing responsiveness to maternal separation, recognition memory, and contact with novel objects. Animals were classified by putative activity levels for the MAOA genotype. The effects of prenatal ketamine exposure were seen only in the context of MAOA genotype. Greater exposure to ketamine resulted in increased activity, less willingness to perform in the memory task, and reduced emotionality and novel-object contact, but only for individuals with the low-activity genotype. Nearly all effects of ketamine were the result of first- and second-trimester exposure. MAOA genotype moderates the role of prenatal ketamine exposure at time points in gestation earlier than have been shown in past research, and is particularly evident for measures of emotionality. These results support the idea that ketamine's use might be best considered in light of individuals' genetic characteristics.

A randomized controlled trial of a wellness intervention for women with fibromyalgia syndrome

OBJECTIVE

To examine the effects of a wellness intervention, Lifestyle Counts, for women with fibromyalgia syndrome on the level of self-efficacy for health-promoting behaviours, health-promoting activity and perceived quality of life.

DESIGN

A randomized controlled single-blinded trial with treatment and attention-control groups.

SETTING

Community in the southwestern United States.

SUBJECTS

Convenience sample of 187 women (98 treatment, 89 attention control) with fibromyalgia syndrome (mean age = 53.08 years, SD 9.86).

INTERVENTION

The two-phase Lifestyle Counts intervention programme included lifestyle change classes for eight weeks, with goal-setting and telephone follow-up for three months. Participants in the attention-control group were offered an equivalent amount of contact in classes on general disease-related information and health education topics and unstructured follow-up phone calls. Participants were followed for a total of eight months after baseline.

OUTCOME MEASURES

Self-report instruments measuring self-efficacy for health behaviours, health-promotion behaviours and health-related quality of life (SF-36 and the Fibromyalgia Impact Questionnaire) were completed at baseline, two months (after the classes), five months (after telephone follow-up) and at eight months.

RESULTS

Both groups improved significantly (P<0.05) over time on the measures of self-efficacy, health behaviours, fibromyalgia impact and quality of life. There were significant group x time interactions for scores on the Health Promoting Lifestyle II subscales of physical activity and stress management.

CONCLUSIONS

The Lifestyle Counts wellness intervention holds promise for improving health-promoting behaviours and quality of life of women with fibromyalgia syndrome.

Co-immunization with IL-15 enhances cellular immune responses induced by a vif-deleted simian immunodeficiency virus proviral DNA vaccine and confers partial protection against vaginal challenge with SIVmac251

Simian immunodeficiency virus (SIV) infection of rhesus macaques is a valuable animal model for human immunodeficiency virus (HIV)-1 vaccine development. Our laboratory recently described the immunogenicity and limited efficacy of a vif-deleted SIVmac239 proviral DNA (SIV/CMVDelta vif) vaccine. The current report characterizes immunogenicity and efficacy for the SIV/CMVDelta vif proviral DNA vaccine when co-inoculated with an optimized rhesus interleukin (rIL)-15 expression plasmid. Macaques co-inoculated with rIL-15 and SIV/CMVDelta vif proviral plasmids showed significantly improved SIV-specific CD8 T cell immunity characterized by increased IFN-gamma ELISPOT and polyfunctional CD8 T cell responses. Furthermore, these animals demonstrated a sustained suppression of plasma virus loads after multiple low dose vaginal challenges with pathogenic SIVmac251. Importantly, SIV-specific cellular responses were greater in immunized animals compared to unvaccinated controls during the initial 12 weeks after challenge. Taken together, these findings support the use of IL-15 as an adjuvant in prophylactic anti-HIV vaccine strategies.

Personality and serotonin transporter genotype interact with social context to affect immunity and viral set-point in simian immunodeficiency virus disease

From the beginning of the AIDS epidemic, stress has been a suspected contributor to the wide variation seen in disease progression, and some evidence supports this idea. Not all individuals respond to a stressor in the same way, however, and little is known about the biological mechanisms by which variations in individuals' responses to their environment affect disease-relevant immunologic processes. Using the simian immunodeficiency virus/rhesus macaque model of AIDS, we explored how personality (Sociability) and genotype (serotonin transporter promoter) independently interact with social context (Stable or Unstable social conditions) to influence behavioral expression, plasma cortisol concentrations, SIV-specific IgG, and expression of genes associated with Type I interferon early in infection. SIV viral RNA set-point was strongly and negatively correlated with survival as expected. Set-point was also associated with expression of interferon-stimulated genes, with CXCR3 expression, and with SIV-specific IgG titers. Poorer immune responses, in turn, were associated with display of sustained aggression and submission. Personality and genotype acted independently as well as in interaction with social condition to affect behavioral responses. Together, the data support an "interactionist" perspective [Eysenck, H.J., 1991. Personality, stress and disease: an interactionist perspective. Psychol. Inquiry 2, 221-232] on disease. Given that an important goal of HIV treatment is to maintain viral set-point as low as possible, our data suggest that supplementing anti-retroviral therapy with behavioral or pharmacologic modulation of other aspects of an organism's functioning might prolong survival, particularly among individuals living under conditions of threat or uncertainty.

Depo-Provera abrogates attenuated lentivirus-induced protection in male rhesus macaques challenged intravenously with pathogenic SIVmac239

BACKGROUND

Progesterone administration prior to intravaginal challenge with pathogenic SIVmac239 decreases the protective efficacy of live attenuated vaccines in rhesus macaques.

METHODS

To determine if progesterone alters the efficacy of live attenuated vaccines through local or systemic effects, seven male rhesus macaques were immunized with SHIV89.6 and then challenged intravenously with SIVmac239. Three of these animals were treated with Depo-Provera 30 days prior to the SIV challenge.

RESULTS

The SHIV animals had significantly lower plasma viral RNA levels than the unimmunized control monkeys, but the Depo-Provera treated, SHIV-immunized animals did not. Despite the lack of protection, the Depo-Provera SHIV animals had strong SIV specific T-cell responses. However, altered patterns of NK frequency and CD38 T-cell expression prior to SIV challenge were observed in Depo-Provera SHIV animals.

CONCLUSIONS

Depo-Provera eliminates live-attenuated lentivirus vaccine efficacy in male rhesus monkeys through systemic effects on antiviral immunity and/or viral replication.

The development of interpersonal aggression during adolescence: the importance of parents, siblings, and family economics

Latent growth curve modeling employed data from a longitudinal study of 451 sibling families to examine parents, siblings, and family economics as factors in individual differences in the developmental course of interpersonal aggression during adolescence. Findings suggest that individual change in interpersonal aggression during adolescence can be predicted by the gender and aggression of one's sibling; predictions varied by the gender composition of the sibling dyad. Rates of parental hostility predicted levels of interpersonal aggression for both older (mean age = 12 years) and younger siblings (mean age = 15), and growth in aggression for younger siblings. Family economic pressure predicted interpersonal aggression of both siblings indirectly through parental hostility. Implications for future research and preventive interventions are discussed.

The Development of Interpersonal Aggression During Adolescence: The Importance of Parents, Siblings, and Family Economics

Latent growth curve modeling employed data from a longitudinal study of 451 sibling families to examine parents, siblings, and family economics as factors in individual differences in the developmental course of interpersonal aggression during adolescence. Findings suggest that individual change in interpersonal aggression during adolescence can be predicted by the gender and aggression of one's sibling; predictions varied by the gender composition of the sibling dyad. Rates of parental hostility predicted levels of interpersonal aggression for both older (mean age = 12 years) and younger siblings (mean age = 15), and growth in aggression for younger siblings. Family economic pressure predicted interpersonal aggression of both siblings indirectly through parental hostility. Implications for future research and preventive interventions are discussed.

Alveoli increase in number but not size from birth to adulthood in rhesus monkeys

Postnatal developmental stages of lung parenchyma in rhesus monkeys is about one-third that of humans. Alveoli in humans are reported to be formed up to 8 yr of age. We used design-based stereological methods to estimate the number of alveoli (N(alv)) in male and female rhesus monkeys over the first 7 yr of life. Twenty-six rhesus monkeys (13 males ranging in age from 4 to 1,920 days and lung volumes from 41.7 to 602 cm(3), 13 females ranging in age from 22 to 2,675 days and lung volumes from 43.5 to 380 cm(3)) were necropsied and lungs fixed, isotropically oriented, fractionated, sampled, embedded, and sectioned for alveolar counting. Parenchymal, alveolar, alveolar duct core air, and interalveolar septal tissue volumes increased rapidly during the first 2 yr with slowed growth from 2 to 7 yr. The rate of change was greater in males than females. N(alv) also showed consistent growth throughout the study, with increases in N(alv) best predicted by increases in lung volume. However, mean alveolar volume showed little relationship with age, lung volume, or body weight but was larger in females and showed a greater size distribution than in males. Alveoli increase in number but not volume throughout postnatal development in rhesus monkeys.

Adolescent alcohol use and adult alcohol disorders: a two-part random-effects model with diagnostic outcomes

Alcohol use is often analyzed by treating the behavior as a single dimension, such as focusing on frequency of use. Based on data from a longitudinal study, this report considers two distinct aspects of semi-continuous alcohol use data. A two-part random-effects model was used to evaluate change in the log-odds and frequency of use from about age 13 to about age 18 years. Change features were then related to the log-odds of later alcohol disorders. Results suggested differences in the two aspects of use over time and their relationships with later disorders. Most important for the purposes of this study, different methods of analyzing antecedents and consequences of alcohol use trajectories were shown to generate both similar and disparate findings.

Analyzing individual differences in sentence processing performance using multilevel models

The use of multilevel models is increasingly common in the behavioral sciences for analyzing hierarchically structured data, including repeated measures data. These models are flexible and easily implemented via a variety of commercially available statistical software programs. We consider their application in the context of an eye-movement experiment testing readers' responses to a semantic plausibility manipulation in temporarily ambiguous sentences. Multilevel models were used to study the relationship between working memory capacity and the extent to which readers were disrupted by syntactic misanalysis. This represented a cross-level interaction between an individual difference measure and a sentence-level characteristic. We compare a multilevel modeling approach to a standard approach based on ANOVA.

Exercise, functional limitations, and quality of life: A longitudinal study of persons with multiple sclerosis

OBJECTIVE

To explore the trajectories of functional limitations, health behaviors (exercise), and quality of life (QOL) and their interrelations over a 5-year time period in a sample of persons with multiple sclerosis (MS).

DESIGN

Descriptive longitudinal survey study.

SETTING

Southwestern United States.

PARTICIPANTS

Convenience sample of 611 people with MS (mean age at time 1, 49.4y). Ninety percent of the participants remained enrolled in the study. Response rates at each annual data collection ranged from 85% to 90% of eligible participants.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

A series of self-report instruments to measure functional limitations, exercise behaviors, and QOL were completed annually over a 5-year period.

RESULTS

Using multivariate latent curve modeling techniques, rates of change in functional limitations correlated negatively with rates of exercise behaviors and QOL ratings. The level of exercise behaviors at time 1 and rate of change in functional limitations were negatively related-suggesting that higher exercise levels at time 1 were related to slower accumulation of functional limitations over time.

CONCLUSIONS

Data analysis methods that allow examination of both the individual and group level of change are particularly appropriate when examining trajectories of change in persons with MS because of the highly individualized progression and presentation of the disease. Findings of this descriptive longitudinal study support the potential positive impact of exercise on the long-term progression of functional limitation and QOL for persons with MS.

Dosage effects of diabetes self-management education for Mexican Americans: the Starr County Border Health Initiative

OBJECTIVE

The objective of this study was to compare two diabetes self-management interventions designed for Mexican Americans: "extended" (24 h of education, 28 h of support groups) and "compressed" (16 h of education, 6 h of support groups). Both interventions were culturally competent regarding language, diet, social emphasis, family participation, and incorporating cultural beliefs.

RESEARCH DESIGN AND METHODS

We recruited 216 persons between 35 and 70 years of age diagnosed with type 2 diabetes >/=1 year. Intervention groups of eight participants and eight support persons were randomly assigned to the compressed or extended conditions. The interventions differed in total number of contact hours over the year-long intervention period, with the major difference being the number of support group sessions held. The same information provided in the educational sessions of the extended intervention was compressed into fewer sessions, thus providing more information during each group meeting.

RESULTS

The interventions were not statistically different in reducing HbA(1c); however, both were effective. A "dosage effect" of attendance was detected with the largest HbA(1c) reductions achieved by those who attended more of the extended intervention. For individuals who attended >/=50% of the intervention, baseline to 12-month HbA(1c) change was -0.6 percentage points for the compressed group and -1.7 percentage points for the extended group.

CONCLUSIONS

Both culturally competent diabetes self-management education interventions were effective in promoting improved metabolic control and diabetes knowledge. A dosage effect was evident; attending more sessions resulted in greater improvements in metabolic control.

Structured latent curve models for the study of change in multivariate repeated measures

This article considers a structured latent curve model for multiple repeated measures. In a structured latent curve model, a smooth nonlinear function characterizes the mean response. A first-order Taylor polynomial taken with regard to the mean function defines elements of a restricted factor matrix that may include parameters that enter nonlinearly. Similar to factor scores, random coefficients are combined with the factor matrix to produce individual latent curves that need not follow the same form as the mean curve. Here the associations between change characteristics in multiple repeated measures are studied. A factor analysis model for covariates is included as a means of relating latent covariates to the factors characterizing change in different repeated measures. An example is provided.

Monozygotic and dizygotic twins' retrospective and current bereavement-related behaviors: an evolutionary perspective

The present study compared bereavement responses of 325 monozygotic (MZ) and 176 dizygotic (DZ) adolescent and adult twins following the loss of their co-twins. A subset of twins completed the Grief Experience Inventory using a retrospective time frame, while a second subset completed it using a current time frame. It was hypothesized that MZ twins (in both retrospective and current groups) would report higher levels of grief-related behavior than DZ twins, consistent with Hamilton's (1964) concept of inclusive fitness. Discriminant function and profile analyses yielded supportive findings, but only for the retrospective MZ and DZ twin comparisons. Females in both groups expressed higher levels of bereavement-related behavior than males. Findings are discussed with reference to theoretical aspects of grief and mourning.

Psychobiological and evolutionary perspectives on coping and health characteristics following loss: a twin study

An analysis of coping, grief and health characteristics is reported for a bereaved monozygotic (MZ) and dizygotic (DZ) same-sex twin sample. The data were examined with reference to psychobiological and evolutionary perspectives on behavior. A Coping Scale, included as part of a comprehensive Twin Loss Survey (TLS), assessed coping with daily responsibilities and activities 1-2 months before the co-twin's death, 1-2 months following the co-twin's death and currently. A Grief Intensity Scale obtained judgments of grief 1-2 months following the loss, and currently. Information on physical symptoms was available from the Somatization Scale of the Grief Experience Inventory. Psychobiological and evolutionary perspectives specified hypotheses for two twin groups: one model was specified to reflect bereavement experiences immediately following loss of the co-twin (retrospective twin group); a second model represented present bereavement response (current twin group). Consistent with psychobiological theory, twins' social closeness showed a positive association with grief intensity which, in turn, affected somatic symptoms and coping efficacy in predicted directions. With respect to evolutionary psychological theory, the effect of zygosity on current grief implicated correlates of genetic relatedness as factors in the bereavement process.

Individual and contextual factors related to family practice residents' assessment and counseling for tobacco cessation

BACKGROUND

Tobacco use is the chief avoidable cause of death in the United States. Physicians, however, are not routinely assessing this risk and providing counseling for risk reduction. This study examines tobacco cessation counseling practices among family practice residents and explores the determinants of residents' smoking-counseling behaviors and counseling duration.

METHODS

One hundred ten family practice residents (response rate = 93.2%) from four Texas residency training programs completed a survey designed to assess tobacco cessation counseling practices.

RESULTS

A high proportion of residents reported that they usually or always assessed tobacco use (59.3%) and advised their patients to quit smoking (80.9%), with a lower proportion reporting specific counseling behaviors (7.3% - 21.9%), referrals (1.8%), or follow-up visits (1.8%). Year of residency, perceived effectiveness, and the interaction between perceived effectiveness and residency year were significantly associated with number of counseling behaviors, and year of residency and perceived effectiveness were significantly associated with counseling duration.

CONCLUSIONS

Faculty physicians should assist residents to implement the Public Health Service-sponsored clinical practice guideline for tobacco control. There is a need to increase behavioral skills and perceived effectiveness for assessing and counseling smokers among first-year residents.

Unique issues faced by deaf individuals entering substance abuse treatment and following discharge

Several barriers can frustrate a deaf individual's intention to enter a substance abuse treatment program. Because few specialized programs work with the Deaf, it is difficult to determine the factors that influence a deaf individual's desire to maintain sobriety following completion of a residential treatment program. A sample of 100 individuals was drawn from the Minnesota Chemical Dependency Program for Deaf and Hard of Hearing Individuals, a model hospital-based inpatient treatment program. The study participants were asked to complete pretreatment and posttreatment surveys upon admission and discharge, respectively, in addition to a follow-up survey, to help determine which background factors might be associated with different treatment outcomes for deaf and hard of hearing persons who completed treatment in the program. Results are presented for the pretreatment and posttreatment assessments, and for the follow-up survey. Study limitations are discussed and recommendations are given for future treatment programs serving deaf and hard of hearing individuals.

The impact of Put Prevention into Practice on selected clinical preventive services in five Texas sites

OBJECTIVE

To determine whether the implementation of the Put Prevention Into Practice (PPIP) office-based system would increase the delivery rates of specific clinical preventive services among demonstration clinics.

METHODS

Chart review was conducted before (n=372) and 33 to 39 months after (n=376) the implementation of the PPIP office-based system in two community health centers and three family practice residency programs in Texas. The population included all adult patients aged > or = 19 years who had presented to the clinic during the study periods.

RESULTS

Documentation of timely cholesterol screening increased from 70% to 84%; smoking assessment, from 56% to 80%; for women, up-to-date Papanicolaou smear, from 70% to 81%; annual mammograms (women aged > or =51), from 30% to 48%; and up-to-date tetanus-diphtheria immunizations, from 19% to 59%. For adults aged > or =66 years, documentation of pneumococcal immunization increased from 22% to 48%, while influenza immunizations improved, although not significantly (45% to 49%). Blood pressure screening was almost universal (99%) at baseline and at 33- to 39-month follow-up.

CONCLUSION

PPIP system changes were associated with an observed increase in delivery of selected clinical preventive services.