Predictors of survival in Alzheimer's disease

Alzheimer's disease (AD) is associated with greater mortality and reduced survival among individuals with Alzheimer's disease as compared to those without dementia. It is uncertain how these survival estimates change when the clinical signs and/or symptoms of comorbid conditions are present in individuals' with Alzheimer's disease. Cardiovascular risk factors such as hypertension, hyperlipidemia, congestive heart failure, coronary artery disease, and diabetes mellitus are common conditions in the aged population. Independently, these factors influence mortality and may have an additive effect on reduced survival in an individual with concomitant Alzheimer's disease. The bulk of the evidence from previous research efforts suggests an association between vascular co-morbidities and Alzheimer's disease incidence, but their role in survival remains to be elucidated. The objective of this proposed study was to examine the effects of cardiovascular comorbidities on the survival experience of individuals with probable Alzheimer's disease in order to identify prognostic factors for life expectancy following onset of disease. This study utilized data from the Baylor College of Medicine Alzheimer's Disease Center (ADC) longitudinal study of Alzheimer's disease and other memory disorders. Individuals between the ages of 55-69, 70-79, and ≥80 had a median survival from date of onset of 9.2 years, 8.0 years, and 7.2 years, respectively (p<0.001) and 5.5 years, 4.3 years, and 3.4 years from diagnosis. Sex was the strongest predictor of death from onset of AD, with females having a 30 percent lower risk compared to males. These findings further support the notion that age (both from onset and from diagnosis) and sex are the strongest predictors of survival among those with AD. ^

Hormone therapy and physical activity as predictors of lung cancer risk and survival: The California Teachers Study

Cigarette smoking is responsible for the majority of lung cancer cases worldwide; however, a proportion of never smokers still develop lung cancer over their lifetime, prompting investigation into additional factors that may modify lung cancer incidence, as well as mortality. Although hormone therapy (HT), physical activity (PA), and lung cancer have been previously examined, the associations remain unclear. This study investigated exposure to HT and PA that may modulate underlying mechanisms of lung cancer etiology and progression among women by using existing, de-identified data from the California Teachers Study (CTS).^ The CTS cohort, established in 1995–1996, has 133,479 active and retired female teachers and administrators, recruited through the California State Teachers Retirement System, and followed annually for cancer diagnosis, death, and change of address. Each woman enrolled in the CTS returned a questionnaire covering a wide variety of issues related to cancer risk and women's health, including recent and past HT use and physical activity, as well as active and environmental cigarette smoke exposure. Complete data to assess the associations between HT and lung cancer risk and survival were available for 60,592 postmenopausal women. Between 1995 and 2007, 727 of these women were diagnosed with invasive lung cancer; 441 of these died. Complete data to assess the associations between PA and lung cancer risk and survival were available for 118,513 women. Between 1995 and 2007, 853 of these women were diagnosed with invasive lung cancer; 516 of these died.^ After careful adjustment for smoking habits and other potential confounders, no measure of HT use was associated with lung cancer risk; however, any HT use (vs. no use) was associated with a decrease in lung-cancer-specific mortality. Specifically, among women who only used estrogen (E-only), decreases in lung cancer mortality were seen for recent use, but not for former use; no association was observed for estrogen plus progestin (E+P). Furthermore, among former users of HT, a statistically significant decrease in lung cancer mortality was observed for E-only use within 5 years prior to baseline, but not for E-only use >5 years prior to baseline. Neither long-term recreational PA nor recent recreational PA alone were associated with lung cancer risk; however, among women with a BMI<25 and ever smokers, high long-term moderate+strenuous PA was associated with a decrease in lung cancer risk. Women with non-local disease showed a decrease in lung cancer mortality associated with increasing duration of strenuous long-term activity, and 1.50-3.00 h/wk/y of recent moderate or recent strenuous PA. Long-term moderate PA was associated with decreased lung cancer mortality in never smokers, whereas recent moderate PA was associated with increased lung cancer mortality in current smokers. ^ Placing our findings in the context of the current literature, HT does not appear to be associated with lung cancer risk and previous studies reporting a protective effect of HT use on lung cancer risk may be subject to residual confounding by smoking. Looking at our findings regarding PA overall, the evidence still remains inconclusive regarding whether or not physical activity influence lung cancer risk or mortality. Our results suggest that recreational PA may associated with decreased lung cancer risk among women with BMI<25 and ever smoking-women; however, residual confounding by smoking should be strongly considered. To our knowledge, this is the first study to investigate lifetime recreational PA and lung cancer mortality among women. Our results contribute to the growing body of knowledge regarding non-smoking-related risk factors for lung cancer incidence and mortality among women. Given the potential clinical and interventional significance, further study and validation of these findings is warranted.^

Role of {\it Mycobacterium avium-intracellulare\/} complex infection in AIDS mortality

Disseminated MAC (dMAC) is the third most prevalent opportunistic infection in AIDS patients. In order to understand the role MAC infection plays in affecting survival of AIDS patients, a cohort of 203 suspected dMAC veterans seen at the Houston Veterans Affairs Medical Center between August 14, 1987 and December 31, 1991 were analyzed. The criteria for suspected dMAC infection was HIV+ men having a CD4+ level $\le$200 cells/mm$\sp3,$ on zidovudine treatment $\ge$1 month and who had any of the following: (a) a confirmed respiratory MAC infection, (b) fever $\ge$101$\sp\circ\rm F$ for $\ge$48 hours, (c) unexplained weight loss of 10 lbs or $\ge$10% BW over 3 months or (d) Hgb $\le$7.5 g/dl or decrease in Hgb $\ge$3.0 g/dl, while on 500-600 mg/day AZT. The study was conducted before the commencement of an effective MAC anti-mycobacterial therapy, so the true course of MAC infection was seen without the confounder of a therapeutic regimen. Kaplan-Meier and Cox regression survival analysis was used to compare 45 MAC culture positive and 118 MAC culture negative veterans. The 1 year survival rate of veterans with documented dMAC infection was 0.37 compared to 0.50 for veterans not acquiring dMAC infection. Significant differences between subgroups were also seen with the variables: PCP prophylaxis, the AIDS indicator disease Candida esophagitis, CD4+ lymphocyte level, CD4 percent lymphocyte level, WBC level, Hgb and Hct levels. Using multivariate modeling, it was determined that PCP prophylaxis (RR = 6.12, CI 2.24-16.68) was a predictor of survival and both CD4% lymphocytes $\le$6.0% (RR = 0.33, CI 0.17-0.68) and WBC level $\le$3000 cells/mm$\sp3$ (RR = 0.60, CI 0.39-0.93) were predictors of mortality. CD4+ level $\le$50 cells/mm$\sp3$ was not a significant predictor of mortality. Although MAC culture status was a significant predictor of mortality in the univariate model, a positive dMAC culture was not a significant predictor of AIDS mortality in the multivariate model. A positive dMAC culture, however, did affect mortality in a stratified analysis when baseline laboratory values were: CD8+ lymphocytes $>$600 cells/mm$\sp3,$ Hgb $>$11.0 g/dl, Hct $>$31.0% and WBC level $>$3000 cells/mm$\sp3.$ ^

Genetic Predictors of Clinical Outcomes in Non-Small Cell Lung Cancer Patients

Lung cancer is the leading cause of cancer-related mortality in the US. Emerging evidence has shown that host genetic factors can interact with environmental exposures to influence patient susceptibility to the diseases as well as clinical outcomes, such as survival and recurrence. We aimed to identify genetic prognostic markers for non-small cell lung cancer (NSCLC), a major (85%) subtype of lung cancer, and also in other subgroups. With the fast evolution of genotyping technology, genetic association studies have went through candidate gene approach, to pathway-based approach, to the genome wide association study (GWAS). Even in the era of GWAS, pathway-based approach has its own advantages on studying cancer clinical outcomes: it is cost-effective, requiring a smaller sample size than GWAS easier to identify a validation population and explore gene-gene interactions. In the current study, we adopted pathway-based approach focusing on two critical pathways - miRNA and inflammation pathways. MicroRNAs (miRNA) post-transcriptionally regulate around 30% of human genes. Polymorphisms within miRNA processing pathways and binding sites may influence patients’ prognosis through altered gene regulation. Inflammation plays an important role in cancer initiation and progression, and also has shown to impact patients’ clinical outcomes. We first evaluated 240 single nucleotide polymorphisms (SNPs) in miRNA biogenesis genes and predicted binding sites in NSCLC patients to determine associations with clinical outcomes in early-stage (stage I and II) and late-stage (stage III and IV) lung cancer patients, respectively. First, in 535 early-stage patients, after correcting multiple comparisons, FZD4:rs713065 (hazard ratio [HR]:0.46, 95% confidence interval [CI]:0.32-0.65) showed a significant inverse association with survival in early stage surgery-only patients. SP1:rs17695156 (HR:2.22, 95% CI:1.44-3.41) and DROSHA:rs6886834 (HR:6.38, 95% CI:2.49-16.31) conferred increased risk of progression in the all patients and surgery-only populations, respectively. FAS:rs2234978 was significantly associated with improved survival in all patients (HR:0.59, 95% CI:0.44-0.77) and in the surgery plus chemotherapy populations (HR:0.19, 95% CI:0.07-0.46).. Functional genomics analysis demonstrated that this variant creates a miR-651 binding site resulting in altered miRNA regulation of FAS, providing biological plausibility for the observed association. We then analyzed these associations in 598 late-stage patients. After multiple comparison corrections, no SNPs remained significant in the late stage group, while the top SNP NAT1:rs15561 (HR=1.98, 96%CI=1.32-2.94) conferred a significantly increased risk of death in the chemotherapy subgroup. To test the hypothesis that genetic variants in the inflammation-related pathways may be associated with survival in NSCLC patients, we first conducted a three-stage study. In the discovery phase, we investigated a comprehensive panel of 11,930 inflammation-related SNPs in three independent lung cancer populations. A missense SNP (rs2071554) in HLA-DOB was significantly associated with poor survival in the discovery population (HR: 1.46, 95% CI: 1.02-2.09), internal validation population (HR: 1.51, 95% CI: 1.02-2.25), and external validation (HR: 1.52, 95% CI: 1.01-2.29) population. Rs2900420 in KLRK1 was significantly associated with a reduced risk for death in the discovery (HR: 0.76, 95% CI: 0.60-0.96) and internal validation (HR: 0.77, 95% CI: 0.61-0.99) populations, and the association reached borderline significance in the external validation population (HR: 0.80, 95% CI: 0.63-1.02). We also evaluated these inflammation-related SNPs in NSCLC patients in never smokers. Lung cancer in never smokers has been increasingly recognized as distinct disease from that in ever-smokers. A two-stage study was performed using a discovery population from MD Anderson (411 patients) and a validation population from Mayo Clinic (311 patients). Three SNPs (IL17RA:rs879576, BMP8A:rs698141, and STK:rs290229) that were significantly associated with survival were validated (pCD74:rs1056400 and CD38:rs10805347) were borderline significant (p=0.08) in the Mayo Clinic population. In the combined analysis, IL17RA:rs879576 resulted in a 40% reduction in the risk for death (p=4.1 × 10-5 [p=0.61, heterogeneity test]). We also validated a survival tree created in MD Anderson population in the Mayo Clinic population. In conclusion, our results provided strong evidence that genetic variations in specific pathways that examined (miRNA and inflammation pathways) influenced clinical outcomes in NSCLC patients, and with further functional studies, the novel loci have potential to be translated into clinical use.

Subjective well -being as predictor of mortality, heart disease, and obesity: Prospective evidence from the Alameda County Study

Based on the World Health Organization's (1965) definition of health, understanding of health requires understanding of positive psychological states. Subjective Well-being (SWB) is a major indicator of positive psychological states. Up to date, most studies of SWB have been focused on its distributions and determinants. However, study of its consequences, especially health consequences, is lacking. This dissertation research examined Subjective Well-being, as operationally defined by constructs drawn from the framework of Positive Psychology, and its sub-scores (Positive Feelings and Negative Feelings) as predictors of three major health outcomes—mortality, heart disease, and obesity. The research used prospective data from the Alameda County Study over 29 years (1965–1994), based on a stratified, randomized, representative sample of the general public in Alameda County, California (Baseline N = 6928). ^ Multivariate analyses (Survival analyses using sequential Cox Proportional Hazard models in the cases of mortality and heart disease, and sequential Logistic Regression analyses in the case of obesity) were performed as the main methods to evaluate the associations of the predictors and the health outcomes. The results revealed that SWB reduced risks of all-cause mortality, natural-cause mortality, and cardiovascular mortality. Positive feelings not only had an even stronger protective effect against all-cause, natural-cause and cardiovascular mortality, but also predicted decreased unnatural-cause mortality which includes deaths from suicide, homicide, accidents, mental disorders, drug dependency, as well as alcohol-related liver diseases. These effects were significant even after adjusted for age, gender, education, and various physical health measures, and, in the case of cardiovascular mortality, obesity and health practices (alcohol consumption, smoking, and physical activities). However, these two positive psychological indicators, SWB and positive feelings, did not predict obesity. And negative feelings had no significant effect on any of the health outcomes evaluated, i.e., all-cause mortality, natural- and unnatural-cause mortality, cardiovascular mortality, or obesity, after covariates were controlled. These findings were discussed (1) in comparison with relevant existing studies, (2) in terms of their implications in health research and promotion, (3) in terms of the independence of positive and negative feelings, and (4) from a Positive Psychology perspective and its significance in Public Health research and practice. ^

Activity of anidulafungin in a murine model of Candida krusei infection: evaluation of mortality and disease burden by quantitative tissue cultures and measurement of serum (1,3)-beta-D-glucan levels.

Experience with anidulafungin against Candida krusei is limited. Immunosuppressed mice were injected with 1.3 x 10(7) to 1.5 x 10(7) CFU of C. krusei. Animals were treated with saline, 40 mg/kg fluconazole, 1 mg/kg amphotericin B, or 10 and 20 mg/kg anidulafungin for 5 days. Anidulafungin improved survival and significantly reduced the number of CFU/g in kidneys and serum beta-glucan levels.

Intensive Family Preservation in Children's Mental Health: Predictors of Placement

This article examines the predictors of placement following IFPSfor a sample of child mental health service recipients and their families. Risk and protective factors vary depending on the time frame under consideration. Immediately following service, children 's level of Social/Legal functioning, a previous group home placement, and the presence of mental health problems for other family members increase risk of placement, while the number of follow-up services serves to lessen risk. Three to six months after service, the presence of a child behavior presenting problem and a projected placement in foster care serve as protective factors, while two service targets, alcohol monitoring and time management, serve to increase risk. Appropriate use of results for program design and for structuring access to services is discussed.

Resting and reactive blood pressure as predictors of ambulatory blood pressure in older hypertensive adults

Background. A review of the literature suggests that Hypertension (HTN) in older adults is associated with sympathetic stimulation that results in increasing blood pressure (BP) reactivity. If clinical assessment of BP captured sympathetic stimulation, it would be valuable for hypertension management. ^ Objectives. The study examined whether reactive change scores from a short BPR protocol, resting blood pressure (BP), or resting pulse pressure (PP) is a better predictor of 24 hour ambulatory BP and BP load in cardiac patients. ^ Method. The study used a single-group design, with both an experimental clinical component and an observational field component. Both components used repeated measurement methods. The study population consisted of 45 adult patients with a mean age of 64.6 ± 8.5 years who were diagnosed with cardiac disease and who were taking anti-hypertensive medication. Blood pressure reactivity was operationalized with a speech protocol. During the speech protocol, BP was measured with an automatic device (Dinamap 825XT) while subjects talked about their health and about their usual day. Twenty-four hour ambulatory BP measurement (Spacelabs 90207 monitor) followed the speech protocol. ^ Results. Resting SBP and resting PP were significant predictors of 24-hour SBP, and resting SBP was a significant predictor of SBP load. No predictors were significant of 24-hour DBP or DBP load. ^ Conclusions. Initial resting BP and PP may be used in clinical settings to assess hypertension management. Future studies are necessary to confirm the ability of resting BP to predict ABP and BP load in older, medicated hypertensives. ^

Predictors of weight stability in women and men: The aerobic center longitudinal study, 1987--1995

It is estimated that more than half the U.S. adult population is overweight or obese as classified by a body mass index of 25.0–29.9 or ≥30 kg/m 2, respectively. Since the current treatment approaches for long-term maintenance of weight loss are lacking, the National Institutes of Health state that an effective approach may be to focus on weight gain prevention. There is a limited body of literature describing how adults maintain a stable weight as they age. It is hypothesized that weight stability is the result of a balance between energy consumption and energy expenditure as influenced by diet, lifestyle, behavior, genetics and environment. The purpose of this research was to examine the dietary intake and behaviors, lifestyle habits, and risk factors for weight change that predict weight stability in a cohort of 2101 men and 389 women aged 20 to 8 7 years in the Aerobic Center Longitudinal Study regardless of body weight at baseline. At baseline, participants completed a maximal exercise treadmill test to determine cardiorespiratory fitness, a medical history questionnaire, which included self-reported measures of weight, dietary behaviors, lifestyle habits, and risk factors for weight change, a three-day diet record, and a mail-back version of the medical history questionnaire in 1990 or 1995. All analyses were performed separately for men and women. Results from multivariate regression analyses indicated that the strongest predictor of follow-up weight for men and women was previous weight, accounting for 87.0% and 81.9% of the variance, respectively. Age, length of follow-up and eating habits were also significant predictors of follow-up weight in men, though these variables only explained 3% of the variance. For women, length of follow-up and currently being on a diet were significantly associated with follow-up weight but these variables explained only an additional 2% of the variance. Understanding the factors that influence weight change has tremendous public health importance for developing effective methods to prevent weight gain. Since current weight was the strongest predictor of previous weight, preventing initial weight gain by maintaining a stable weight may be the most effective method to combat the increasing prevalence of overweight and obesity. ^

Predictors of participation in genetic testing for hereditary breast and ovarian cancer

Up to 10% of all breast and ovarian cancers are attributable to mutations in cancer susceptibility genes. Clinical genetic testing for deleterious gene mutations that predispose to hereditary breast and ovarian cancer (HBOC) syndrome is available. Mutation carriers may benefit from following high-risk guidelines for cancer prevention and early detection; however, few studies have reported the uptake of clinical genetic testing for HBOC. This study identified predictors of HBOC genetic testing uptake among a case series of 268 women who underwent genetic counseling at The University of Texas M. D. Anderson Cancer Center from October, 1996, through July, 2000. Women completed a baseline questionnaire that measured psychosocial and demographic variables. Additional medical characteristics were obtained from the medical charts. Logistic regression modeling identified predictors of participation in HBOC genetic testing. Psychological variables were hypothesized to be the strongest predictors of testing uptake—in particular, one's readiness (intention) to have testing. Testing uptake among all women in this study was 37% (n = 99). Contrary to the hypotheses, one's actual risk of carrying a BRCA1 or BRCA2 gene mutation was the strongest predictor of testing participation (OR = 15.37, CI = 5.15, 45.86). Other predictors included religious background, greater readiness to have testing, knowledge about HBOC and genetic testing, not having female children, and adherence to breast self-exam. Among the subgroup of women who were at ≥10% risk of carrying a mutation, 51% (n = 90) had genetic testing. Consistent with the hypotheses, predictors of testing participation in the high-risk subgroup included greater readiness to have testing, knowledge, and greater self-efficacy regarding one's ability to cope with test results. Women with CES-D scores ≥16, indicating the presence of depressive symptoms, were less likely to have genetic testing. Results indicate that among women with a wide range of risk for HBOC, actual risk of carrying an HBOC-predisposing mutation may be the strongest predictor of their decision to have genetic testing. Psychological variables (e.g., distress and self-efficacy) may influence testing participation only among women at highest risk of carrying a mutation, for whom genetic testing is most likely to be informative. ^

Genetic predictors of bladder cancer with an emphasis on methylation-related genes

Although tobacco exposure remains the prevailing risk factor for bladder cancer (BC), only a small percentage of exposed individuals develop cancer, suggesting that tobacco-related carcinogenesis is modulated by genetic susceptibility and possibly by DNA methylation-related events. Methylation patterns established by DNA methyltransferases (DNMTs) are influenced by dietary folate and genetic polymorphisms in the methylene-tetrahydrofolate reductase gene (MTHFR). Therefore, we hypothesized that DNA methylation-related genes, such as DNMT3B and MTHFR, might modulate BC risk. ^ In a study of 514 Caucasian BC cases and 498 healthy Caucasian controls examining the DNMT3B C46359T polymorphism, CC genotype was found to be a risk factor in women (Odds Ratio (OR) = 1.79), but not in men. This risk was further increased among women who were never smokers, consumed low dietary folate, and had adverse variants of MTHFR. In addition, higher DNMT3B expression among smokers was a risk factor (OR = 4.27) and correlated with genetic variants of the DNMT3B C46359T polymorphism, providing salient evidence for the risk associated with the CC variant. This suggests that the DNMT3B CC variant may confer a predisposition toward aberrant de novo methylation of CpG islands in critical tumor suppressor genes. ^ The convergence of alterations in DNMT3B, associated with promoter methylation, and reduced dietary folate consumption, accompanying global hypomethylation and genetic instability, may act synergistically to promote bladder carcinogenesis, especially in women. The results of this study unveiled new gender-specific paradigms of BC risk for women and demonstrated that this risk can be modified by folate consumption as well as polymorphisms in the folate pathway. ^

Sociodemographic characteristics as predictors of successful smoking cessation among a group of Hispanic Spanish speaking smokers

Few studies have examined predictors of smoking abstinence among Hispanic groups. The purpose of this dissertation was to examine the relations of sociodemographic characteristics and smoking related factors with smoking abstinence among a group of Hispanic Spanish speaking smokers. This study utilized previously collected data from Hispanic Spanish-speaking smokers (N = 246) who participated in a study entitled Smoking Cessation Services for Hispanic Smokers in Texas. ^ The first study examined sociodemographic characteristics and smoking related mechanisms that predicted smoking abstinence among this group. Two of the characteristics were related to smoking abstinence, marital status and acculturation level. Being unmarried increased the likelihood of being abstinent at the 12 week assessment (OR = 1.80). Those in the high acculturation group were twice as likely to be abstinent (OR = 2.24). Of the smoking related mechanisms, those with higher positive reinforcement expectancies were less likely to be abstinent (OR = .86), as were those with a higher level of affiliative attachment (OR = .86), a higher level of craving (OR = .78) and a higher tolerance to the effect of smoking (OR = .74). The second study was to examine the relationship of objective measures of socioeconomic status (SES) (income, education, or employment) with smoking abstinence among this group. This study also compared the relationship of a subjective measure of SES (Social Status Ladder) to smoking abstinence. None of the objective measures of SES were related to smoking abstinence at the 12 week assessment. The subjective measure of SES did predict smoking abstinence (OR = 1.9) indicting that those that rated themselves ≤4 on the SES scale were more likely to be abstinent. ^ Although this group was recruited using various methods across the state of Texas, the fact that they preferred to interact with the counselor in Spanish may limit the study findings. The results of this study highlight the need for research to examine specific subgroups of people and understand the special circumstances that influence their health behaviors. Furthering our knowledge of the relations between sociodemographic characteristics and smoking cessation could lead to interventions that reduce disparities in smoking cessation. ^

Psychosocial and environmental predictors of calcium intake, physical activity and bone health among adolescent girls

Objectives. The purpose of this study was to identify the psychosocial and environmental predictors and the pathways they use to influence calcium intake, physical activity and bone health among adolescent girls. Methods. A secondary data analysis using a cross-sectional and longitudinal study design was implemented to examine the associations of interest. Data from the Incorporating More Physical Activity and Calcium in Teens (IMPACT) study collected in 2001-2003 were utilized for the analyses. IMPACT was a 1½ year nutrition and physical activity intervention study conducted among 718 middle-school girls in central Texas. Hierarchical regression modeling and Structural Equation Modeling (SEM) were used to determine the psychosocial predictors of calcium intake, physical activity and bone health at baseline. Hierarchical regression was used to determine if psychosocial factors at baseline were significant predictors of calcium intake and physical activity at follow-up. Data was adjusted for included BMI, lactose intolerance, ethnicity, menarchal status, intervention and participation in 7th grade PE/athletics. Results. Results of the baseline regression analysis revealed that calcium self-efficacy and milk availability at home were the strongest predictors of calcium intake. Friend engagement in physical activity, physical activity self-efficacy and participation in sports teams were the strongest predictors of physical activity. Finally, physical activity outcome expectations, social support and participation in sports teams were significant predictors of stiffness index at baseline. Results of the baseline SEM path analysis found that outcome expectations and milk availability at home directly influenced calcium intake. Knowledge and calcium self-efficacy indirectly influenced calcium intake with outcome expectations as the mediator. Physical activity self-efficacy and social support had significant direct and indirect influence on physical activity with participation in sports teams as the mediator. Participation in sports teams had a direct effect on both physical activity and stiffness index. Results of regression analysis for baseline predicting follow-up showed that participation in sports teams, self-efficacy, outcome expectations and social support at baseline were significant predictors of physical activity at follow-up. Conclusion. Results of this study reinforce the relevance of addressing both, psychosocial and environmental factors which are critical when developing interventions to improve bone health among adolescent girls. ^

Predictors of HIV testing among injection drug users

The current analysis examined the association of several demographic and behavioral variables with prior HIV testing within a population of injection drug users (IDUs) living in Harris County, Texas in 2005 (n=563). After completing the initial univariate analyses of all potential predictors, a multivariable model was created. This model was designed to guide future intervention efforts. Data used in this analysis were collected by the University of Texas School of Public Health in association with the Houston Department of Health and Human Services for the first IDU cycle of the National HIV Behavioral Surveillance System. About 76% of the IDUs reported previously being tested for HIV. Demographic variables that displayed a significant association with prior testing during the univariate analyses include age, race/ethnicity, birth outside the United States, education level, recent arrest, and current health insurance coverage. Several drug-related and sexual behaviors also demonstrated significant associations with prior testing, including age of first injection drug use, heroin use, methamphetamine use, source of needles or syringes, consistent use of new needles, recent visits to a shooting gallery or similar location, previous alcohol or drug treatment, condom use during their most recent sexual encounter, and having sexual partners who also used injection drugs. Additionally, the univariate analyses revealed that recent use of health or HIV prevention services was associated with previously testing for HIV. The final multivariable model included age, race/ethnicity, recent arrest, previous alcohol or drug treatment, and heroin use. ^

Psychosocial job characteristics as predictors of overall health: Results from a community-based cross-sectional study conducted in southeast Texas in 2001 and 2002

Stress at the workplace exposes people to increased risk for poor physical and/or mental health. Recently psychological and social disadvantages have been proven to place the worker at risk for mental or physical health outcomes. The overall purpose of this study was to study full time employed study subjects and (1) describe the various psychosocial job characteristics in a population of low income individuals stratified by race/ethnicity residing in Houston and Brownsville, Texas and (2) examine the associations between psychosocial job characteristics and physical, mental, and self rated health. It was observed that having a low level of education is associated with having very little or no control, security, and social support at the workplace. Being Mexican American was associated with having good job control, job security, job social support and having a less demanding job. Furthermore, the psychosocial job characteristics were associated with mental health outcomes but not with physical and self rated health. ^