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Richard P Sloan

Publications and source records attributed to Richard P Sloan.

16 recordsLinked to original sources
PubMed2006

Religious involvement and health outcomes among older persons in Taiwan.

We use data from a nationally representative, longitudinal survey of older Taiwanese to examine the relationship between religious involvement-including religious affiliation, religious attendance, beliefs, and religious practices-and self-reported measures of overall health status, mobility limitations, depressive symptoms, and cognitive function; clinical measures of systolic and diastolic blood pressure, serum interleukin-6, and 12-h urinary cortisol; and 4-year mortality. Frequency of religious attendance shows the strongest, most consistent association with health outcomes. But, with only one exception, this relationship disappears in the presence of controls for health behaviors, social networks, and prior health status. Religious attendance remains significantly associated with lower mortality even after controlling for prior self-assessed health status, but the coefficient is substantially reduced. Other aspects of religiosity are only sporadically associated with health and, in all cases, private religious practices and stronger beliefs are associated with worse health; again, this relationship disappears after controlling for prior health status. These results suggest that reverse causality may partly account for both the positive and negative correlations between religiosity and health. We find no significant associations between religious involvement and biological markers. Notably, even after controlling for prior health, participation in social activities has a more robust effect on health than religious attendance. Consequently, we question whether the purported health benefits are attributable to religion or to social activity in general.

Aged↗
PubMed2006

Science, medicine, and intercessory prayer.

Among the many recent attempts to demonstrate the medical benefits of religious activity, the methodologically strongest seem to be studies of the effects of distant intercessory prayer (IP). In these studies, patients are randomly assigned to receive standard care or standard care plus the prayers or "healing intentions" of distant intercessors. Most of the scientific community has dismissed such research, but cavalier rejection of studies of IP is unwise, because IP studies appear to conform to the standards of randomized controlled trials (RCTs) and, as such, would have a significant advantage over observational investigations of associations between religious variables and health outcomes. As we demonstrate, however, studies of IP fail to meet the standards of RCTs in several critical respects. They fail to adequately measure and control exposure to prayer from others, which is likely to exceed IP and to vary widely from subject to subject, and whose magnitude is unknown. This supplemental prayer so greatly attenuates the differences between the treatment and control groups that sample sizes are too large to justify studies of IP. Further, IP studies generally do not specify the outcome variables, raising problems of multiple comparisons and Type 1 errors. Finally, these studies claim findings incompatible with current views of the physical universe and consciousness. Unless these problems are solved, studies of IP should not be conducted.

Faith Healing↗
PubMed2005

The MANTRA II study.

Explore the source record for details and available documents.

Angioplasty, Balloon, Coronary↗
PubMed2005

New approach to the statistical analysis of cardiovascular data.

Fourier-based approaches to analysis of variability of R-R intervals or blood pressure typically compute power in a given frequency band (e.g., 0.01-0.07 Hz) by aggregating the power at each constituent frequency within that band. This paper describes a new approach to the analysis of these data. We propose to partition the blood pressure variability spectrum into more narrow components by computing power in 0.01-Hz-wide bands. Therefore, instead of a single measure of variability in a specific frequency interval, we obtain several measurements. The approach generates a more complex data structure that requires a careful account of the nested repeated measures. We briefly describe a statistical methodology based on generalized estimating equations that suitably handles this more complex data structure. To illustrate the methods, we consider systolic blood pressure data collected during psychological and orthostatic challenge. We compare the results with those obtained using the conventional methods to compute blood pressure variability, and we show that our approach yields more efficient results and more powerful statistical tests. We conclude that this approach may allow a more thorough analysis of cardiovascular parameters that are measured under different experimental conditions, such as blood pressure or heart rate variability.

Algorithms↗
PubMed2005

Socioeconomic status and health: is parasympathetic nervous system activity an intervening mechanism?

BACKGROUND: The link between socioeconomic status (SES) and health is widely recognized but the pathophysiologic mechanisms are not well understood. We tested the hypothesis that parasympathetic nervous system (PNS) regulation is one such mechanism. METHODS: In a cross-sectional study, electrocardiogram-derived RR interval variability (RRV), a non-invasive index of cardiac PNS regulation, and SES, measured as educational attainment and income, were collected in 756 subjects in the CARDIA study of heart disease in young adults. RESULTS: Relative to those with less than a high school education, those with high school to college and post-college education had 26% (beta = 0.233) and 43% (beta = 0.355) greater low frequency (LF) RRV, respectively, adjusted for age, sex, and race. For high frequency (HF) RRV, race interacted with income: relative to low income whites, intermediate and high income whites had 133 and 191% greater HF power, respectively, while intermediate and high income blacks had 32 and 44% greater HF RRV, respectively, relative to low income blacks. CONCLUSIONS: Numerous studies demonstrate that psychosocial stressors reduce cardiac parasympathetic regulation and that SES disparities are associated with increasing social stress proportional to the degree of disparity. Data from the current study suggest that PNS regulation may be a mechanism linking the stressful effects of low SES to increased morbidity and mortality.

Adult↗
PubMed2005

Religious attendance as a predictor of survival in the EPESE cohorts.

BACKGROUND: Interest has arisen in recent years in the relationship between religious involvement and health outcomes. Although most of the early literature consists of studies with methodological flaws, some recent well-conducted reports show that religious attendance is associated with reduced mortality in selected subgroups and populations. METHODS: In this study, we investigated the relationship between religious attendance and mortality using the 14,456 participants in the National Institute of Aging-funded 'Established Populations for Epidemiologic Studies of the Elderly'. RESULTS: Our analyses show that after controlling for important prognostic factors, frequent religious attendance was associated with increased survival in the entire cohort [risk ratio (RR) = 0.78, 95% Confidence interval (CI) 0.70-0.88]. However, stratified analyses show that this association exists for only two of the four sites. CONCLUSIONS: We conclude that the association between religious attendance and survival is not robust and may depend upon unknown confounders and covariates.

Aged↗
PubMed2004

Fetal heart rate reactivity differs by women's psychiatric status: an early marker for developmental risk?

OBJECTIVE: To determine whether there are differences in fetal heart rate (FHR) reactivity associated with women's psychiatric status. METHOD: In 57 women in their 36th to 38th week of pregnancy (mean age 27 +/- 6 years), electrocardiogram, blood pressure (BP), respiration (RSP), and FHR were measured during baseline and a psychological challenge (a Stroop color-word matching task). Subjects underwent the Structured Clinical Interview for DSM-IV (SCID) and completed the Spielberger State-Trait Anxiety Inventory prior to testing. RESULTS: There was a significant main effect of maternal diagnostic group on FHR reactivity during the Stroop task even after controlling for birth weight and women's BP reactivity (F4,44 = 2.68, p =.04). Fetuses of depressed women had greater heart rate increases compared to fetuses of women with anxiety disorders and those of healthy, low-anxiety women (post hoc comparisons using the Fisher protected least significant difference test; t = 4.12, p <.05; t = 4.72, p <.01, respectively). There was a similar pattern comparing fetuses of healthy, high-anxiety women to the same two groups (t = 3.29, p <.05; t = 3.99, p <.05, respectively). There were no group differences in FHR during a resting baseline period (F4,52 = 1.2, p =.35). CONCLUSIONS: Maternal mood disturbance is associated with alterations in children's physiological reactivity prior to birth.

Adult↗
PubMed2003

Deriving heart period variability from blood pressure waveforms.

International standards for calculating heart period variability (HPV) from a series of R-wave intervals (R-R) in an electrocardiographic (ECG) recording have been widely accepted. It is possible, and potentially useful in various settings, to use systolic blood pressure waveform intervals to estimate HPV, but the validity of HPV derived from blood pressure (BP) waveforms has not been established. To test the reliability between BP- and ECG-derived HPV indexes, we evaluated data from 234 healthy adults in four studies of HPV reactivity to stress. Study conditions included resting baseline, arithmetic, Stroop test, speech presentation, and orthostatic tilt. Continuous ECG and BP recordings were sampled at a rate of 500 Hz, scored by the same methods, and used to calculate heart rate and time- and frequency-domain measures of HPV. Overall, reliability between the two methods was very high for computing heart rate and HPV indexes. High-frequency HPV indexes were somewhat less reliably computed. In conclusion, in healthy adults, with the use of appropriate methods, BP waveforms can produce reliable indexes of HPV.

Adult↗
PubMed2003

Low arterial compliance in young African-American males.

Hypertension remains a common public health challenge because of its prevalence and increase in co-morbid cardiovascular diseases. Black males have disproportionate pathophysiological consequences of hypertension compared with any other group in the United States. Alterations in arterial wall compliance and autonomic function often precede the onset of disease. Accordingly, our purpose was to investigate whether differences exist in arterial compliance and autonomic function between young, healthy African-American males without evidence of hypertension and age- and gender-matched non-African-American males. All procedures were carried out noninvasively following rest. Arterial compliance was calculated as the integrated area starting at the well-defined nadir of the incisura of the dicrotic notch to the end of diastole of the radial artery pulse wave. Power spectral analysis of heart rate and blood pressure variability provided distributions representative of parasympathetic and sympathetic modulations and sympathovagal balance. Baroreflex sensitivity (BRS) was calculated using the sequence method. Thirty-two African-American and twenty-nine non-African-American males were comparable in anthropometrics and negative family history of hypertension. t-Tests revealed lower arterial compliance (5.8 +/- 2.4 vs. 8.6 +/- 4.0 mmHg. s; P = 0.0017), parasympathetic modulation (8.9 +/- 1.1 vs. 9.7 +/- 1.1 ln ms2; P = 0.0063), and BRS (13.7 +/- 7.3 vs. 21.1 +/- 8.5 ms/mmHg; P = 0.0007) and higher sympathovagal balance (2.9 +/- 3.2 vs. 1.5 +/- 1.1; P = 0.03) in the African-American group. In summary, differences exist in arterial compliance and autonomic balance in African-American males. These alterations may be antecedent markers of disease and valuable in the detection of degenerative cardiovascular processes in individuals at risk.

Adult↗
PubMed2003

Evaluation of blood pressure and baroreflex sensitivity by radial artery tonometry versus finger arteriolar photoplethysmography.

BACKGROUND: Published normative data of noninvasive blood pressures (BPs) and autonomic modulations have been primarily derived from the finger arteriole using the Finapres (Ohmeda Co., Englewood, CO), a device that is no longer manufactured. Currently, beat-to-beat BP are obtained from the radial artery using the Colin tonometer. METHODS: We compared BP and autonomic parameters in a crossover design between the two devices in 29 subjects during seated rest and a 0.1-Hz breathing protocol. In addition, we tested whether finger arteriolar BP differences were due to pressure changes exerted by the radial tonometer. RESULTS: Uniformly, BP measured at the radial artery were significantly higher than those from the finger arteriole. Radial BP (106 +/- 19.5 mm Hg) were higher than finger arteriolar BP (95.8 +/- 13.7 mm Hg) (P <.005). Tonometric baroreflex sensitivity (BRS) (24.0 +/- 18 msec/mm Hg) was higher compared to photoplethysmographic BRS (12.0 +/- 7.7 msec/mm Hg; P <.0003). Systolic BP (radial artery) (115 +/- 25 mm Hg) were higher compared to finger arteriolar BP (97.7 +/- 19 mm Hg; P <.0025) during breathing, as was BRS (25.9 +/- 11.6 msec/mm Hg v 21.5 +/- 11.6 msec/mm Hg; P <.05). Differences in the low frequency systolic BP (LF(SBP)), representative of sympathetic vasomotor modulation, between the two methods, whether absolute, normalized, or log-transformed were not observed. CONCLUSIONS: There were no differences in arteriolar BP values in the presence or absence of radial artery tonometric pressure. These findings indicate that differences exist in systolic BP and BRS using the tonometer (radial artery) versus the Finapres (Ohmeda Co.) (finger arteriole). Furthermore, these differences are not due to pressure exerted by the radial artery tonometer that supplies blood to the finger arteriole.

Adult↗
PubMed2003

Effects of women's stress-elicited physiological activity and chronic anxiety on fetal heart rate.

This study examined the effects of pregnant women's acute stress reactivity and chronic anxiety on fetal heart rate (HR). Thirty-two healthy third trimester pregnant women were instrumented to monitor continuous electrocardiography, blood pressure, respiration, and fetal HR. Subjects completed the trait anxiety subscale of the State Trait Anxiety Index, then rested quietly for a 5-minute baseline period, followed by a 5-minute Stroop color-word matching task and a 5-minute recovery period. Fetal HR changes during women's recovery from a stressful task were associated with the women's concurrently collected HR and blood pressure changes (r =.63, p <.05). Fetal HR changes during recovery, as well as during women's exposure to the Stroop task, were correlated with their mothers' trait anxiety scores (r =.39, p <.05 and r = -.52, p <.01, respectively). Finally, a combination of measures of women's cardiovascular activity during recovery and trait anxiety scores accounted for two thirds of the variance in fetal HR changes during the same recovery period (r =.69, p <.001). The results from this study link changes in fetal behavior with acute changes in women's cardiovascular activity after psychological stress and women's anxiety status. This indicates that variations in women's emotion-based physiological activity can affect the fetus and may be centrally important to fetal development.

Adult↗
PubMed2002

Temporal stability of acute stress-induced changes in leukocyte subsets and cellular adhesion molecules in older adults.

This study investigated the temporal stability of enumerative immune and catecholamine responses to acute psychosocial stress in 67 Alzheimer's caregivers ages 56-82 years (45 women and 22 men) who were required to prepare and deliver two 3-min speeches on three occasions at 2-week and 6-week intervals. All leukocyte subsets and adhesion molecules (CD62L and CD11a) changed significantly from rest to postspeak at each of the three testing sessions (p's <.0005). Responses showed moderate to high temporal stability across baseline and absolute task values (r's =.65-.96). Reliability was predictably lower for both forms of change scores (r's = -.16-.64). The level of temporal stability achieved is comparable to that seen previously in younger adults, indicating that acute psychosocial stress produces reliable changes in circulating leukocytes and cell adhesion molecules in older adults.

Aged↗
PubMed2002

Claims about religious involvement and health outcomes.

Claims about religion, spirituality, and health have recently appeared with increasing frequency, in both the popular media and professional journals. These claims have asserted that there are a great many studies in the literature that have examined relations between religious involvement and health outcomes and that the majority of them have shown that religious people are healthier. We examined the validity of these claims in two ways: (a) To determine the percentage of articles in the literature that were potentially relevant to such a claim, we identified all English-language articles with published abstracts identified by a Medline search using the search term religion in the year 2000, and (b) to examine the quality of the data in articles cited as providing supportfor such a claim, we examined all articles in the area of cardiovascular disease and hypertension cited by two comprehensive reviews of the literature. Of the 266 articles published in the year 2000 and identified by the Medline search, only 17% were relevant to claims of health benefits associated with religious involvement. About half of the articles cited in the comprehensive reviews were irrelevant to these claims. Of those that actually were relevant, many either had significant methodological flaws or were misrepresented, leaving only afew articles that could truly be described as demonstrating beneficial effects of religious involvement. We conclude that there is little empirical basis for assertions that religious involvement or activity is associated with beneficial health outcomes.

Cardiovascular Diseases↗
PubMedDate not supplied

Hostility, interpersonal interactions, and ambulatory blood pressure.

OBJECTIVE: This study examined aspects of the transactional model of hostility and health by investigating relationships among hostility, interpersonal interactions, and ambulatory blood pressure in a healthy community sample. MATERIALS AND METHODS: Participants included 65 female and 39 male healthy adults between the ages of 18 and 46 years. Ambulatory blood pressure (ABP) and diary data on mood and social interactions were obtained every 20 minutes for 1 day. Mixed models regression analyses were used to evaluate the relationships among hostility, interpersonal interactions, and ABP. RESULTS: Trait hostility was positively associated with the frequency and intensity of negative interactions and was negatively associated with the frequency and intensity of positive interactions. Interacting with others was associated with increases in systolic blood pressure (SBP) and diastolic blood pressure (DBP). The magnitude of the increase in blood pressure was positively associated with the degree to which the interaction was perceived as negative. Hostility was not directly associated with ABP/heart rate (HR) or ABP/HR responses during any interactions or negative interactions. However, there was an interaction between hostility and negative interaction intensity for DBP, suggesting that hostility moderates the effects of negative interactions on DBP. Specifically, increases in the intensity of negative interactions were associated with increases in DBP for participants with high, but not low, hostility. CONCLUSIONS: The results provide partial support for the notion that hostility may be associated with risk for cardiovascular disease through its effects on interpersonal interactions and their cardiovascular correlates.

Adolescent↗
PubMedDate not supplied

Risk factors, confounding, and the illusion of statistical control.

When experimental designs are premature, impractical, or impossible, researchers must rely on statistical methods to adjust for potentially confounding effects. Such procedures, however, are quite fallible. We examine several errors that often follow the use of statistical adjustment. The first is inferring a factor is causal because it predicts an outcome even after "statistical control" for other factors. This inference is fallacious when (as usual) such control involves removing the linear contribution of imperfectly measured variables, or when some confounders remain unmeasured. The converse fallacy is inferring a factor is not causally important because its association with the outcome is attenuated or eliminated by the inclusion of covariates in the adjustment process. This attenuation may only reflect that the covariates treated as confounders are actually mediators (intermediates) and critical to the causal chain from the study factor to the study outcome. Other problems arise due to mismeasurement of the study factor or outcome, or because these study variables are only proxies for underlying constructs. Statistical adjustment serves a useful function, but it cannot transform observational studies into natural experiments, and involves far more subjective judgment than many users realize.

Bias↗