Population differences in associations of serotonin transporter promoter polymorphism (5HTTLPR) di- and triallelic genotypes with blood pressure and hypertension prevalence.

Based on prior research finding the 5HTTLPR L allele associated with increased cardiovascular reactivity to laboratory stressors and increased risk of myocardial infarction, we hypothesized that the 5HTTLPR L allele will be associated with increased blood pressure (BP) and increased hypertension prevalence in 2 large nationally representative samples in the United States and Singapore. METHODS: Logistic regression and linear models tested associations between triallelic (L'S', based on rs25531) 5HTTLPR genotypes and hypertension severity and mean systolic and diastolic blood pressure (SBP and DBP) collected during the Wave IV survey of the National Longitudinal Study of Adolescent to Adult Health (Add Health, N=11,815) in 2008-09 and during 2004-07 in 4196 Singaporeans. RESULTS: In US Whites, L' allele carriers had higher SBP (0.9 mm Hg, 95% CI=0.26-1.56) and greater odds (OR=1.23, 95% CI=1.10-1.38) of more severe hypertension than those with S'S' genotypes. In African Americans, L' carriers had lower mean SBP (-1.27mm Hg, 95% CI=-2.53 to -0.01) and lower odds (OR = 0.78, 95% CI=0.65-0.94) of more severe hypertension than those with the S'S' genotype. In African Americans, those with L'L' genotypes had lower DBP (-1.13mm Hg, 95% CI=-2.09 to -0.16) than S' carriers. In Native Americans, L' carriers had lower SBP (-6.05mm Hg, 95% CI=-9.59 to -2.51) and lower odds of hypertension (OR = 0.34, 95% CI=0.13-0.89) than those with the S'S' genotype. In Asian/Pacific Islanders those carrying the L' allele had lower DBP (-1.77mm Hg, 95% CI=-3.16 to -0.38) and lower odds of hypertension (OR = 0.68, 95% CI=0.48-0.96) than those with S'S'. In the Singapore sample S' carriers had higher SBP (3.02mm Hg, 95% CI=0.54-5.51) and DBP (1.90mm Hg, 95% CI=0.49-3.31) than those with the L'L' genotype. CONCLUSIONS: These findings suggest that Whites carrying the L' allele, African Americans and Native Americans with the S'S' genotype, and Asians carrying the S' allele will be found to be at higher risk of developing cardiovascular disease and may benefit from preventive measures.

Emotion regulation and emotional distress: The mediating role of hope on reappraisal and anxiety/depression in newly diagnosed cancer patients.

PURPOSE: A proportion of newly diagnosed cancer patients may experience anxiety and depression. Emotion suppression has been associated with poorer psychoemotional outcomes, whereas reappraisal may be an adaptive emotion regulation strategy. Few studies have examined potential mechanisms linking reappraisal to psychoemotional outcomes in cancer patients. This study aims to replicate findings on reappraisal and suppression and further examines if hope mediates the association between reappraisal and anxiety/depression in patients newly diagnosed with cancer. METHODS: Participants were 144 adult cancer patients (65.3% female, mean age = 48.96 years, SD = 9.23). Patients completed a set of study questionnaires, including the Emotion Regulation Questionnaire, Adult Hope Scale, and the Hospital Anxiety and Depression Scale. Path analysis was used to examine if hope mediated the association between reappraisal and anxiety/depression. RESULTS: Prevalence of anxiety was 39.6% and depression was 25.0%. Reappraisal and hope were correlated with lower anxiety and depression, whereas suppression was correlated with higher anxiety and depression. The hypothesized mediation model provided fit to the data, comparative fit index = 0.95, Tucker-Lewis index = 0.94, root-mean-square-error of approximation = 0.05. There was a significant indirect effect of reappraisal on anxiety and depression via hope, b = -0.95, SE = 0.42, 95% confidence interval = -1.77 to -0.12, whereas the direct effect of reappraisal was nonsignificant. CONCLUSION: The study findings suggest that hope mediated the association between reappraisal and anxiety/depression outcomes. Moreover, the high prevalence of anxiety and depression implies a need for healthcare providers to attend to the psychoemotional needs of newly diagnosed cancer patients.

Population frequencies of the Triallelic 5HTTLPR in six Ethnicially diverse samples from North America, Southeast Asia, and Africa.

Genetic differences between populations are potentially an important contributor to health disparities around the globe. As differences in gene frequencies influence study design, it is important to have a thorough understanding of the natural variation of the genetic variant(s) of interest. Along these lines, we characterized the variation of the 5HTTLPR and rs25531 polymorphisms in six samples from North America, Southeast Asia, and Africa (Cameroon) that differ in their racial and ethnic composition. Allele and genotype frequencies were determined for 24,066 participants. Results indicated higher frequencies of the rs25531 G-allele among Black and African populations as compared with White, Hispanic and Asian populations. Further, we observed a greater number of 'extra-long' ('XL') 5HTTLPR alleles than have previously been reported. Extra-long alleles occurred almost entirely among Asian, Black and Non-White Hispanic populations as compared with White and Native American populations where they were completely absent. Lastly, when considered jointly, we observed between sample differences in the genotype frequencies within racial and ethnic populations. Taken together, these data underscore the importance of characterizing the L-G allele to avoid misclassification of participants by genotype and for further studies of the impact XL alleles may have on the transcriptional efficiency of SLC6A4.

Cardiovascular responses to stress in Singapore and India.

BACKGROUND: Epidemiological studies have shown significant ethnic differences in coronary heart disease death rates with South Asians showing significantly greater coronary heart disease mortality than other groups. PURPOSE: This research examined ethnic differences in cardiovascular reactivity (CVR) among Chinese, Malays and Indians in Singapore as well as a sample of Indians living in India. METHODS: Experiment 1 examined differences across 303 Chinese, Malay and Indian undergraduates in Singapore, while Experiment 2 looked at differences in CVR between Indian participants from Singapore, and 145 Indians living in India. Systolic and diastolic blood pressure (SBP, DBP), heart rate (HR), cardiac index (CI) and total peripheral resistance index (TPRI) were measured during baselines and five laboratory tasks. RESULTS: Ethnicity main effects for SBP and CI reactivity were obtained in Experiment 1, with Indians showing significantly lower BP and CI reactivity than the Chinese and Malays. Significant main effects for sex were found with females showing lower reactivity than males for TPRI, and greater reactivity than males for HR and CI. Experiment 2 found that participants from India showed higher reactivity for SBP, HR and CI, while Indian participants from Singapore showed higher TPRI reactivity. These differences, however, often varied by task. CONCLUSIONS: These results point to differences in CVR among ethnic groups in Singapore as well as between Indians living in India and those living in Singapore. These differences may reflect cultural differences and need to be explored further with respect to their relationship to different rates of coronary heart disease among these groups.

Culture moderates the cardiovascular consequences of anger regulation strategy.

PURPOSE: This research examined cultural differences in experiential and cardiovascular outcomes of three anger regulation strategies (expression, suppression and reappraisal). METHODS: Forty-five Chinese and 45 Caucasian females participated in a laboratory experiment in which role play was used to induce anger. During this role play participants were instructed to either express or suppress their feelings or engage in cognitive reappraisal. Emotional experience was measured before and after the role play. Cardiovascular indices were measured continuously during the experiment. RESULTS: Significant interactions were obtained such that Caucasians showed stronger cardiovascular responses to suppression than expression of anger whereas the opposite was true for Chinese. CONCLUSIONS: These results demonstrate that physiological consequences of emotion regulation strategies vary by cultural background. Possible reasons as well as implications of these findings are discussed.

Ethnicity, gender, genotype, and anger as related to nocturnal dipping.

Bishop, Pek, and Ngau (2005) found a significant interaction in Singapore between anger and nocturnal dipping among Indians but not Chinese and Malays. The current study examines the role of 5-HTTLPR genotype in this relationship. Two hundred thirty-one undergraduates participated in up to 4 days of 24-h ambulatory monitoring, completed the State-Trait Anger Expression Inventory, and provided blood samples for genotyping of 5-HTTLPR. Results indicated individuals with two copies of the short allele (SS) showed reduced dipping when they were high in Outward Anger (OA) but increased dipping when they were low in OA. Further, for Indian men only, dipping was reduced for individuals having the SS genotype when they were low on Anger In and increased when they were high on Anger In. These data provide further evidence for the role of 5-HTTLPR in cardiovascular risk as well as ethnic differences in the 5-HTTLPR-phenotype relationship. They also provide further evidence for 5-HTTLPR as a "plasticity gene."

An S-shaped relationship between changes in appraisals and changes in emotions.

Previous research on appraisal theories of emotion has shown that emotions and appraisals are related but has not specified the nature of the relationships. This research examined the functional forms of appraisal-emotion relationships and demonstrated that for all seven appraisals studied, appraisals relate to emotions in an S-shaped (ogival) fashion: Changes in appraisals at extreme levels are associated with only small changes in emotions, but changes at moderate levels are associated with substantial changes in emotions. With a few exceptions, ogival relationships were found for the relationships between seven appraisals (Goal Achievement Expectancy, Agency, Control, Certainty, Fairness, Pleasantness, and Motive Congruence) and numerous relevant emotions across different sample-types, cultures, and methods.

Appraisal underpinnings of affective chronometry: the role of appraisals in emotion habituation.

In light of the lack of studies examining the cognitive components of affective chronometry, this research examined the appraisals associated with emotion habituation, using anger as the emotion of focus. Anger and its appraisals were assessed repeatedly over a day in the participants' naturalistic contexts. The trajectory of decline in anger over time after its first appearance was found to be a function of chronic coping styles. More importantly, the trajectories of anger-related appraisals generally corresponded to that of anger and were also moderated by coping styles in ways consistent with the moderating effects of coping styles on anger. Implications of these results for affective chronometry research and for appraisal research are discussed.

Perceived threat, risk perception, and efficacy beliefs related to SARS and other (emerging) infectious diseases: results of an international survey.

PURPOSE: To study the levels of perceived threat, perceived severity, perceived vulnerability, response efficacy, and self-efficacy for severe acute respiratory syndrome (SARS) and eight other diseases in five European and three Asian countries. METHOD: A computer-assisted phone survey was conducted among 3,436 respondents. The questionnaire focused on perceived threat, vulnerability, severity, response efficacy, and self-efficacy related to SARS and eight other diseases. RESULTS: Perceived threat of SARS in case of an outbreak in the country was higher than that of other diseases. Perceived vulnerability of SARS was at an intermediate level and perceived severity was high compared to other diseases. Perceived threat for SARS varied between countries in Europe and Asia with a higher perceived severity of SARS in Europe and a higher perceived vulnerability in Asia. Response efficacy and self-efficacy for SARS were higher in Asia compared to Europe. In multiple linear regression analyses, country was strongly associated with perceived threat. CONCLUSIONS: The relatively high perceived threat for SARS indicates that it is seen as a public health risk and offers a basis for communication in case of an outbreak. The strong association between perceived threat and country and different regional patterns require further research.

Avian influenza risk perception, Europe and Asia.

During autumn 2005, we conducted 3,436 interviews in European and Asian countries. We found risk perceptions of avian influenza to be at an intermediate level and beliefs of efficacy to be slightly lower. Risk perceptions were higher in Europe than in Asia; efficacy [corrected] beliefs were lower in Europe than in Asia.

Social support schemas, trait anger, and cardiovascular responses.

This study examined the influence of activated support schemas on cardiovascular reactivity (CVR) during an anger-recall interview. Eighty Chinese female undergraduates wrote about a supportive tie or a casual acquaintance and subsequently disclosed an anger-provoking event while their heart rate (HR), systolic blood pressure (SBP) and diastolic blood pressure (DBP) were measured. Compared to participants in the 'acquaintance' condition, those in the 'support' condition showed lower HR, SBP and DBP reactivity, as well as smaller state anger increases and less negative appraisals of the recalled anger event. Reactivity increased as a function of trait anger. High trait anger individuals also had greater increases in state anger and more negative appraisals of the recalled event compared to their low trait anger counterparts. Support schema activation reduced the effects of trait anger on CVR such that high trait anger individuals in the 'support' condition had significantly lower CVR compared to high trait anger individuals in the 'acquaintance' condition. These findings suggest that social support schemas may have beneficial effects even in the absence of actual, enacted support.

Blunted cardiovascular responses to daytime activities as related to reduced nocturnal blood pressure decline.

BACKGROUND: Individuals showing less than a 10% decline in blood pressure at night ("nondippers") are known to be at increased risk for hypertension and other cardiovascular conditions. PURPOSE: This research tested the assertion by Räikkönen et al. (1) that nondippers show blunted cardiovascular responses to activities during daytime hours. METHODS: Ambulatory blood pressure and impedance monitoring was performed with 149 young adults in Singapore. At each daytime blood pressure reading, participants completed a computerized questionnaire indicating location, posture, physical activities, feelings, and social interactions. RESULTS: Significant interactions between dipper status and feeling tired, location, posture, and physical activity provided qualified support for the blunting hypothesis. However, blunting of BP responses was not attributable to blunting of either cardiac output or total peripheral resistance responses. CONCLUSION: Nondippers appear to show blunted daytime responses to certain types of daytime activities. However, these effects are limited and appear to be the result of different mechanisms than those responsible for reduced nighttime blood pressure decline.

The use of ecological momentary assessment to test appraisal theories of emotion.

Although appraisal theories have received strong empirical support, there are methodological concerns about the research, including biased recall, heuristic responding, ethical issues, and weak and unrealistic induction of emotions in laboratories. To provide a more ecologically valid test of appraisal theories, the authors used ecological momentary assessment, in which the emotions and appraisals of Singaporean police officers were measured online over the course of an ordinary workday. The research focused on happiness. Support was obtained for predictions, demonstrating the generalizability of appraisal theories to a nonlaboratory setting and circumventing the shortcomings of previously used methodologies. Also, evidence was obtained that happiness was reported primarily in association with a specific combination of 3 relevant appraisals: high pleasantness, high perceived control, and low moral violation.

Ethnicity, sex, trait anger, and nocturnal blood pressure decline.

This study examined the relationship of trait anger to nocturnal blood pressure decline among Singaporean young adults. One hundred forty-nine participants (51 Chinese, 51 Malays, 47 Indians, 49.7% men) participated in 24-h ambulatory monitoring for blood pressure and hemodynamic measures. Significant interactions were obtained between ethnicity and trait anger for systolic blood pressure and mean arterial pressure such that trait anger was significantly and negatively related to nocturnal blood pressure decline for Indians whereas this was not true for Chinese or Malays. Significant sex x trait anger interactions were obtained for systolic blood pressure, diastolic blood pressure, and mean arterial pressure in which trait anger was negatively related to blood pressure decline for men but not for women. Overall the results suggest that trait anger is a significant factor affecting nocturnal blood pressure decline particularly among Indians and men.

The relationship of hostility, negative affect and ethnicity to cardiovascular responses: an ambulatory study in Singapore.

This study tested the hypotheses that ambulatory heart rate and blood pressure would be higher for individuals high but not low in hostility when they experienced negative affect or social stress and that this interaction would be stronger for Indians compared with other Singapore ethnic groups. Ambulatory blood pressure monitoring was done on 108 male Singapore patrol officers as they went about their daily duties. After each BP measurement participants completed a computerized questionnaire including items on emotional experience. Individuals high in hostility showed higher systolic blood pressure when reporting negative affect whereas this was not true for those low in hostility. Ethnic differences were obtained such that Indians showed an increase in mean arterial pressure when angered whereas MAP was negatively related to anger for Malays and unrelated for Chinese. Also a three-way interaction between ethnicity, hostility, and social stress indicated that hostility and social stress interacted in their effects on DBP for Indian participants but not for Chinese or Malays. Finally, a three-way interaction was obtained between ethnicity, hostility and negative affect for heart rate in which heart rate increased with increasing levels of negative affect for Chinese high in hostility and Malays low in hostility but decreased with increasing negative affect for all other participants. These data are consistent with higher CHD rates among individuals high in hostility and also provide additional evidence on ethnic differences in cardiovascular reactivity in Singapore.

SARS risk perception, knowledge, precautions, and information sources, the Netherlands.

Severe acute respiratory syndrome (SARS)-related risk perceptions, knowledge, precautionary actions, and information sources were studied in the Netherlands during the 2003 SARS outbreak. Although respondents were highly aware of the SARS outbreak, the outbreak did not result in unnecessary precautionary actions or fears.

Cardiovascular reactivity of Singaporean male police officers as a function of task, ethnicity and hostility.

OBJECTIVE: This research examined hemodynamic processes in cardiovascular reactivity (CVR) as a function of task, ethnicity and trait hostility. METHOD: One hundred and fourteen male patrol officers from the Singapore Police Force participated in this experimental study. Trait hostility was measured using the interpersonal hostility assessment technique to derive a hostile behavior index (HBI). Heart rate, blood pressure and hemodynamic measures were taken while participants performed three tasks: mental arithmetic, number reading and anger recall (AR). RESULTS: AR elicited the greatest blood pressure, vascular and cardiac output reactivity. HBI scores were positively related to systolic blood pressure reactivity during AR for Malays whereas this was not true for Indians and Chinese. Across tasks Indians with high HBI scores appeared to be cardiac reactors whereas the reactivity patterns for Malays and Chinese were undifferentiated. Self-report of negative mood was not related to CVR. CONCLUSION: These results are consistent with the higher rates of coronary heart disease deaths among Indians as well as the higher rates for hypertension among Malays in Singapore.