Carotid Intima-Media Thickness and the Risk of Sudden Cardiac Death: The ARIC Study and the CHS.

Background Sudden cardiac death (SCD) is associated with severe coronary heart disease in the great majority of cases. Whether carotid intima-media thickness (C-IMT), a known surrogate marker of subclinical atherosclerosis, is associated with risk of SCD in a general population remains unknown. The objective of this study was to investigate the association between C-IMT and risk of SCD. Methods and Results We examined a total of 20 862 participants: 15 307 participants of the ARIC (Atherosclerosis Risk in Communities) study and 5555 participants of the CHS (Cardiovascular Health Study). C-IMT and common carotid artery intima-media thickness was measured at baseline by ultrasound. Presence of plaque was judged by trained readers. Over a median of 23.5 years of follow-up, 569 participants had SCD (1.81 cases per 1000 person-years) in the ARIC study. Mean C-IMT and common carotid artery intima-media thickness were associated with risk of SCD after adjustment for traditional risk factors and time-varying adjustors: hazard ratios (HRs) with 95% CIs for fourth versus first quartile were 1.64 (1.15-2.63) and 1.49 (1.05-2.11), respectively. In CHS, 302 participants developed SCD (4.64 cases per 1000 person-years) over 13.1 years. Maximum C-IMT was associated with risk of SCD after adjustment: HR (95% CI) for fourth versus first quartile was 1.75 (1.22-2.51). Presence of plaque was associated with 35% increased risk of SCD: HR (95% CI) of 1.37 (1.13-1.67) in the ARIC study and 1.32 (1.04-1.68) in CHS. Conclusions C-IMT was associated with risk of SCD in 2 biracial community-based cohorts. C-IMT may be used as a marker of SCD risk and potentially to initiate early therapeutic interventions to mitigate the risk.

Disability and recovery of independent function in obstructive lung disease: the cardiovascular health study.

BACKGROUND: Chronic obstructive lung disease frequently leads to disability. Older patients may experience transitions between states of disability and independence over time. OBJECTIVE: To identify factors associated with transition between states of disability and independent function in obstructive lung disease. METHODS: We analyzed data on 4,394 participants in the Cardiovascular Health Study who completed prebronchodilator spirometry. We calculated the 1-year probability of developing and resolving impairment in ≥1 instrumental activity of daily living (IADL) or ≥1 activity of daily living (ADL) using transition probability analysis. We identified factors associated with resolving disability using relative risk (RR) regression. RESULTS: The prevalence of IADL impairment was higher with moderate (23.9%) and severe (36.9%) airflow obstruction compared to normal spirometry (22.5%; p < 0.001). Among participants with severe airflow obstruction, 23.5% recovered independence in IADLs and 40.5% recovered independence in ADLs. In the adjusted analyses, airflow obstruction predicted the development of IADL, but not ADL impairment. Participants with severe airflow obstruction were less likely to resolve IADL impairment [RR 0.67 and 95% confidence interval (CI) 0.49-0.94]. Compared to the most active individuals (i.e. who walked ≥28 blocks per week), walking less was associated with a decreased likelihood of resolving IADL impairment (7-27 blocks: RR 0.81 and 95% CI 0.69-0.86 and <7 blocks: RR 0.73 and 95% CI 0.61-0.86). Increased strength (RR 1.16 and 95% CI 1.05-1.29) was associated with resolving IADL impairment. CONCLUSIONS: Disability is common in older people, especially in those with severe airflow obstruction. Increased physical activity and muscle strength are associated with recovery. Research is needed on interventions to improve these factors among patients with obstructive lung disease and disability.

Effects of respiratory and non-respiratory factors on disability among older adults with airway obstruction: the Cardiovascular Health Study.

BACKGROUND: High rates of disability associated with chronic airway obstruction may be caused by impaired pulmonary function, pulmonary symptoms, other chronic diseases, or systemic inflammation. METHODS: We analyzed data from the Cardiovascular Health Study, a longitudinal cohort of 5888 older adults. Categories of lung function (normal; restricted; borderline, mild-moderate, and severe obstruction) were delineated by baseline spirometry (without bronchodilator). Disability-free years were calculated as total years alive and without self-report of difficulty performing &γτ;1 Instrumental Activities of Daily Living over 6 years of follow-up. Using linear regression, we compared disability-free years by lung disease category, adjusting for demographic factors, body mass index, smoking, cognition, and other chronic co-morbidities. Among participants with airflow obstruction, we examined the association of respiratory factors (FEV1 and dyspnea) and non-respiratory factors (ischemic heart disease, congestive heart failure, diabetes, muscle weakness, osteoporosis, depression and cognitive impairment) on disability-free years. RESULTS: The average disability free years were 4.0 out of a possible 6 years. Severe obstruction was associated with 1 fewer disability-free year compared to normal spirometry in the adjusted model. For the 1,048 participants with airway obstruction, both respiratory factors (FEV1 and dyspnea) and non-respiratory factors (heart disease, coronary artery disease, diabetes, depression, osteoporosis, cognitive function, and weakness) were associated with decreased disability-free years. CONCLUSIONS: Severe obstruction is associated with greater disability compared to patients with normal spirometery. Both respiratory and non-respiratory factors contribute to disability in older adults with abnormal spirometry.

Bidirectional relationship between cognitive function and pneumonia.

RATIONALE: Relationships between chronic health conditions and acute infections remain poorly understood. Preclinical studies suggest crosstalk between nervous and immune systems. OBJECTIVES: To determine bidirectional relationships between cognition and pneumonia. METHODS: We conducted longitudinal analyses of a population-based cohort over 10 years. We determined whether changes in cognition increase risk of pneumonia hospitalization by trajectory analyses and joint modeling. We then determined whether pneumonia hospitalization increased risk of subsequent dementia using a Cox model with pneumonia as a time-varying covariate. MEASUREMENTS AND MAIN RESULTS: Of the 5,888 participants, 639 (10.9%) were hospitalized with pneumonia at least once. Most participants had normal cognition before pneumonia. Three cognition trajectories were identified: no, minimal, and severe rapid decline. A greater proportion of participants hospitalized with pneumonia were on trajectories of minimal or severe decline before occurrence of pneumonia compared with those never hospitalized with pneumonia (proportion with no, minimal, and severe decline were 67.1%, 22.8%, and 10.0% vs. 76.0%, 19.3%, and 4.6% for participants with and without pneumonia, respectively; P < 0.001). Small subclinical changes in cognition increased risk of pneumonia, even in those with normal cognition and physical function before pneumonia (ß = -0.02; P < 0.001). Participants with pneumonia were subsequently at an increased risk of dementia (hazard ratio, 2.24 [95% confidence interval, 1.62-3.11]; P = 0.01). Associations were independent of demographics, health behaviors, other chronic conditions, and physical function. Bidirectional relationship did not vary based on severity of disease, and similar associations were noted for those with severe sepsis and other infections. CONCLUSIONS: A bidirectional relationship exists between pneumonia and cognition and may explain how a single episode of infection in well-appearing older individuals accelerates decline in chronic health conditions and loss of functional independence.

Obesity is associated with a lower resting oxygen saturation in the ambulatory elderly: results from the cardiovascular health study.

BACKGROUND: The contribution of obesity to hypoxemia has not been reported in a community-based study. Our hypothesis was that increasing obesity would be independently associated with lower SpO2 in an ambulatory elderly population. METHODS: The Cardiovascular Health Study ascertained resting SpO2 in 2,252 subjects over age 64. We used multiple linear regression to estimate the association of body mass index (BMI) with SpO2 and to adjust for potentially confounding factors. Covariates including age, sex, race, smoking, airway obstruction (based on spirometry), self reported diagnosis of emphysema, asthma, heart failure, and left ventricular function (by echocardiography) were evaluated. RESULTS: Among 2,252 subjects the mean and median SpO2 were 97.6% and 98.0% respectively; 5% of subjects had SpO2 values below 95%. BMI was negatively correlated with SpO2 (Spearman R = -0.27, P < .001). The mean difference in SpO2 between the lowest and highest BMI categories (< 25 kg/m(2) and ≥ 35 kg/m(2)) was 1.33% (95% CI 0.89-1.78%). In multivariable linear regression analysis, SpO2 was significantly inversely associated with BMI (1.4% per 10 units of BMI, 95% CI 1.2-1.6, for whites/others, and 0.87% per 10 units of BMI, 95% CI 0.47-1.27, for African Americans). CONCLUSIONS: We found a narrow distribution of SpO2 values in a community-based sample of ambulatory elderly. Obesity was a strong independent contributor to a low SpO2, with effects comparable to or greater than other factors clinically associated with lower SpO2.

Effects of friendship closeness in an adolescent group HIV prevention intervention.

Although many interventions for youth rely, explicitly or implicitly, on group effects, sparse theoretical or empirical attention has been paid to the rationale for choosing a small-group design. The present study assesses the role of friendship closeness among youth in prevention intervention groups in shaping their HIV risk-related attitudes, intentions, perceived self-efficacy and perceived norms. Data from an experimental test of a group HIV prevention intervention are used to assess the relationship of friendship on cognitive outcomes at posttest and 6-month follow-up, in a multilevel regression design. Friendship among group members was assessed at baseline and post-intervention, for youth in the experimental intervention and in a control, career exploration, condition. Level of friendship within the group was positively related to attendance and enjoyment of the intervention in the control group only. Most cognitive outcomes were unaffected by individual or group levels of friendship closeness, but those effects observed were opposite to those desired. Friendly groups were no more likely to converge in their cognitions over time than were less-friendly groups. The need for more research on the effects of friendship on intervention outcomes, and for multilevel analyses of group effects, are discussed.

Replicating a teen HIV/STD preventive intervention in a multicultural city.

Although there are now several adolescent HIV and STD preventive interventions of demonstrated efficacy in the literature, little is understood about the portability of these interventions. This study replicated Stanton's Focus on Kids intervention, developed for inner city African American adolescents, in a different population, transferring it to a multicultural city. Despite careful replication of the original study's procedures, youth in the preventive intervention condition of the replication study did not improve in attitudes, perceived norms, self-efficacy, or intentions toward sexual initiation, condom use, or abstinence compared with a carefully matched control condition. We discuss several possible reasons for this failure to replicate, concluding that the most likely reason is the lower rates of sexual activity among youth in the replication city.

Condom use, frequency of sex, and number of partners: multidimensional characterization of adolescent sexual risk-taking.

Sexual health research often relies on single risk indicators. However multi-variable composites may better capture the underlying construct of risk-taking. Latent Profile Analysis identified subgroups based on condom use consistency, partner numbers, and sex frequency among 605 adolescents. Three profiles were identified for each of grades 8 to 10 (Condom Users, Few Partners, and Risk-Takers) and 4 in grades 11 and 12 (Condom Users, One Partner Two Partners, and Risk-Takers). Inconsistent condom use groups reported more non-condom (and often less effective) birth control use and STD and pregnancy histories. Females had greater representation in the Few Partners, One Partners, and Two Partners groups, which also contained increasing proportions of participants in each subsequent year. Males had greater representation in the Risk-Takers group. A profile approach to measurement has methodological advantages, can add to substantive knowledge, and can inform content, timing, and targets of sexual health interventions.

Teens speak out about HIV/AIDS: focus group discussions about risk and decision-making.

PURPOSE: To better understand the factors teens consider when making decisions regarding sex and condom use. METHODS: Twenty-one same-sex focus groups were conducted with a total of 92 male and female teens from a range of high school programs; schools were selected based on the range of programs and diversity of students enrolled. Focus group moderators facilitated groups using a set of open-ended key questions about sexual decision-making and HIV/AIDS for each group; discussion on a specific topic area continued until no new information was generated. Group discussions were tape-recorded and transcribed, and themes were identified through independent content analysis of the transcriptions and assistant moderator notes. RESULTS: Although teens acquire HIV/AIDS knowledge in school and are aware of positive and negative outcomes of engaging in sexual behavior, many times the information does not seem salient or personally relevant and thus is not used in making decisions related to having sex. In general, results indicate that boys and girls seem to have different ideas/reasons for having or not having sex. Boys relate to the physical nature of sex, whereas girls relate to the emotional aspects. Teens report being bored with AIDS education, but suggest needing information that is more relevant for them. CONCLUSIONS: Attempts should be made to make HIV education more relevant for teens so that they use the information they have when making decisions about safer sexual behavior. Different approaches may be needed for boys and girls.

Children's beliefs about smoking.

Children's beliefs about smoking were examined in a multi-ethnic urban sample of 4th through 7th grade children. Results showed that, relative to those in earlier grades, children in higher grades held more positive beliefs about the positive outcomes of smoking and the long-term negative consequences of smoking, but there was no association between grade level and beliefs about the immediate negative consequences of smoking. Children in higher grades also perceived more favorable norms toward smoking. There were few gender or race/ethnicity differences at these ages in children's beliefs about smoking. These outcome and normative beliefs were related to smoking behavior. Of the nine beliefs about the effects of smoking, all but two were significantly related to smoking behavior.