Blood pressure response to orthostatic and mental challenge in African-American women taking oral contraceptives.

BACKGROUND: Contraceptive use among women with an elevated risk of cardiovascular disease and stroke has generated little concern among primary care physicians. African Americans in the southeastern region of the United States are particularly vulnerable to hypertension but are often neglected in research studies of cardiovascular disease. The current study examines the effect of oral contraceptive use by African-American women on blood pressure response to orthostatic and mental challenges. METHODS: One hundred African-American women between the ages of 19 and 29 years were recruited from the student populations of Meharry Medical College and Flask University in Tennessee for a study of oral contraceptive use and blood pressure. Of 95 subjects on whom complete data were collected, 31 were taking oral contraceptives (OCs). As a measure of orthostatic challenge, each subject's blood pressure was monitored by a Dinamap automated instrument while she moved from a supine to sitting to standing position. To test blood pressure reactivity to mental challenge, a subset of 34 subjects (10 OC users and 24 nonusers) were monitored while they attempted to perform a frustrating cognitive task on a computer. RESULTS: There were no differences between users and nonusers of oral contraceptives with respect to the amount of change in blood pressure associated with either the orthostatic or mental challenge. Levels of systolic blood pressure and mean arterial pressure, however, were consistently higher in subjects using oral contraceptives (P < .05) under both testing conditions. Systolic blood pressure levels were 6.7 mm Hg to 9.7 mm Hg higher in OC users during each of the three conditions of orthostatic challenge and 4.4 mm Hg to 7.4 mm Hg higher during each of the four periods of mental challenge. Among OC users, mean arterial pressure levels were 2.9 mm Hg to 4.7 mm Hg higher during orthostatic challenge and 5.0 mm Hg to 8.3 mm Hg higher during mental challenge. CONCLUSIONS: While absolute levels of systolic blood pressure never exceeded 126 mm Hg under either testing condition, the difference in blood pressure levels between the OC users and nonusers warrants concern about the long-term effects of oral contraceptive use among African-American women. Although all OC users in this study were taking low-dose formulations, OC use did not eliminate the risk of elevated blood pressure in this population. Our findings suggest that caution is warranted and that alternative birth control methods should be advised for African-American women who have additional risk factors for cardiovascular disease.

Factors associated with elective Norplant removal in black and white women.

Premature removal of contraceptive implants (Norplant [levonorgestrel implants], Wyeth-Ayerst Laboratories, Philadelphia, Pennsylvania) is a cause of a sizable national medical expenditure in the United States. Understanding the factors that influence the decision to remove the implants and being able to predict which users are likely to elect discontinuation prematurely could provide useful information for counseling patients as they are considering contraceptive implants so that potentially enormous long-term savings could be achieved. This study surveyed 98 women who had Norplant inserted and removed between January 1991 and December 1994. Data were collected from chart review, and when necessary, a questionnaire was used to extract information not found in the chart. The chi-squared statistic and t-test were used to compare demographic variables. All but one subject received comprehensive pre-implant counseling. The main reason given for electively removing the Norplant prematurely was irregular menstrual bleeding (60%). Pre-implant counseling did not influence the decision for removal. These results indicate the importance of clarifying patients' doubts regarding menstrual bleeding irregularities during follow-up visits rather than relying on the information patients received during preimplant counseling.

PIP: Premature removal of contraceptive implants (Norplant) is a cause of a sizable national medical expenditure in the US. Understanding the factors that influence the decision to remove the implants and being able to predict which users are likely to elect discontinuation prematurely could provide useful information for counseling patients as they are considering contraceptive implants so that potentially enormous long-term savings could be achieved. This study surveyed 98 women who had Norplant inserted and removed between January 1991 and December 1994. Data were collected from chart review, and, when necessary, a questionnaire was used to extract information not found in the chart. The chi-squared statistic and t-test were used to compare demographic variables. All but one subject received comprehensive pre-implant counseling. The main reason given for electively removing the Norplant prematurely was irregular menstrual bleeding (60%). Pre-implant counseling did not influence the decision for removal. These results indicate the importance of clarifying patients' doubts regarding menstrual bleeding irregularities during follow-up visits rather than relying on the information patients received during pre-implant counseling.

Skin tone, hostility, and blood pressure in young normotensive African Americans.

Several studies have found a positive relationship between darkness of skin tone and blood pressure in African Americans. This has raised speculation about the relative contributions of genetic and/or psychosocial factors in the mediation of this relationship. Using a laboratory stress protocol, we performed cardiovascular reactivity testing with 42 male and 40 female African-American college students after pre-testing them on measures of hostility using four psychometric scales derived from the Minnesota Multiphasic Personality Inventory (MMPI). Skin tone measures were obtained with a reflectance spectrophotometer. In the combined sample of males and females, we found a weak but statistically significant positive relationship between darker skin tone and systolic blood pressure (p = 0.03). However, males were significantly darker than females (p = .005) suggesting that the skin tone and blood pressure relationship is an artifact of gender. No differences in patterns of cardiovascular habituation or levels of hostility were found between dark and light subjects. Discussion of these results focuses on the weak statistical relationship found in this and other studies and the specificity of previous findings based on educational and socioeconomic factors.

Condemnation of homosexuality in the black community: a gender-specific phenomenon?

While it is commonly accepted that homosexuality finds less tolerance in the black community, little or no research has addressed this issue empirically. In the context of an epidemiological investigation of AIDS-related attitudes, 2006 state employees were surveyed to compare the condemnatory orientation of blacks and whites towards homosexuality. One item measured endorsement of a hostile proposition concerning the deleterious impact of AIDS on the homosexual population. Greater relative endorsement was found of the proposition by blacks confirming the hypothesis that less social tolerance of homosexuality exists in the black community. Analyses of gender, educational achievement, religious preference, and marital status revealed that the racial difference in condemnation of homosexuality was derived almost exclusively from a difference in attitude between black and white females. The primary source of this difference may stem from the black female perception that homosexuality exacerbates the developing problem of a decreasing pool of available black males already affected by integration, racially disproportionate incarceration rates, and relatively high rates of premature death among black males from heart disease, cancer, AIDS, substance abuse, and violence.

The relationship of blood pressure to a brief measure of anger during routine health screening.

A brief questionnaire (12 items) was developed to assess aspects of anger that could be expeditiously obtained during health screenings where medical students and residents can acquire valuable research and clinical experience simultaneously. Blood pressures were measured immediately upon sitting and after 3 minutes in 179 subjects who attended a health fair in Nashville. The questionnaire was administered after both blood pressure measurements were acquired. Scores on the measure of anger correlated significantly (P = .0009) with resting systolic blood pressure (SBP) in both blacks and whites while a measure of "John Henryism" showed no correlation with blood pressure in either group (P = .81). The findings are consistent with the literature in supporting a connection between anger and blood pressure but do not support the relationship between John Henryism and blood pressure.

Racial differences in affirmation of personal habit change to prevent HIV infection.

METHODS: In the context of an epidemiological investigation of AIDS-related knowledge, attitudes, and practices, 2,006 employees of the Tennessee Mental Health and Mental Retardation residential facilities were surveyed to test the hypothesis that blacks have been differentially sensitized to their disproportionate level of HIV vulnerability. RESULTS: We found that blacks were significantly more likely than whites to affirm personal habit changes to prevent HIV infection (P less than 0.00001) and significantly more likely to reject the notion that AIDS is not a threat to rural areas of the United States (P less than 0.00001). CONCLUSION: These data were interpreted to be suggestive evidence that blacks have been effectively sensitized to the disproportionate threat of AIDS to the black community and may represent an increased receptivity of blacks to the adoption of HIV preventive practices.

Calcium attenuates cardiovascular reactivity to sodium and stress in blacks.

The roles of dietary and behavioral factors in the etiology of hypertension are not well understood. Vulnerability to hypertension is thought to be affected by a complex interaction of nutritional, genetic, neurophysiological, and psychosocial influences. We studied cardiovascular reactivity to sodium and stress in a group of 29 normotensive young men who were vulnerable to hypertension by virtue of familial and/or racial factors. Subjects with positive and negative parental histories of hypertension were provided all meals for five days during which blood pressure was monitored before each meal. Two groups were given 300 mEq/day dietary sodium with either 1100 mg/day or 410 mg/day dietary calcium. A third group consumed a 10mEq sodium diet with low dietary calcium. On the fifth day of the diet all subjects were tested for cardiovascular reactivity using a modified Stroop test as a mentally challenging task. Adaptation of systolic blood pressure (SBP) from the first to the fifth breakfast was most pronounced in subjects consuming high calcium with high sodium. Perseveration of SBP reactivity to repeated mental challenge was found in subjects who consumed high sodium with low calcium and in subjects with positive parental histories of hypertension. The perseverative phenomenon was particularly well-defined in subjects who had the highest urinary excretion of calcium. Our findings suggest a prophylactic influence of dietary calcium and its retention on cardiovascular reactivity to sodium and stress. We also elucidate a theoretical proposition concerning the role of neurophysiological inhibitory capacity in the transition from normotension to the chronic dysregulatory state of essential hypertension.

Manifest hostility may affect habituation of cardiovascular reactivity in blacks.

In a study of cardiovascular reactivity to dietary manipulation of sodium and calcium, we pretested 30 young black normotensive males who were equally divided by positive and negative parental histories of hypertension with a 12-item anger questionnaire we devised and the Cook-Medley Hostility, Manifest Hostility, Overcontrolled Hostility, and Inhibited Hostility scales of the Minnesota Multiphasic Personality Inventory. Contrary to expectations, we found no correlation of resting blood pressure or cardiovascular reactivity to repeated mental demands with the two measures of inhibited hostility. We did, however, find resistance to habituation of cardiovascular reactivity in subjects with high Manifest Hostility and positive family histories of essential hypertension. Our findings suggest that vulnerability to hypertension may be revealed by the perseveration of blood pressure reactivity to repeated mental challenge. We propose that the perseveration of blood pressure reactivity is a disinhibitory phenomenon caused by a difficulty in the management of multiple inhibitory demands that disrupts the natural course of habituation and could be an important etiologic factor in essential hypertension.

Contrasting perceptions of distress by research personnel and their spinal cord injured subjects.

Theoretical approaches to the understanding of psychological adjustment in spinal cord injury have recently experienced a re-examination which seriously questions the traditional "stage theory" of adjustment. Despite limited empirical validation at best, the stage theory has not only enjoyed an unchallenged popularity amongst rehabilitation professionals but often has been imposed upon new SCI patients as a necessary criterion for hospital discharge. Experienced professionals have also been shown to exaggerate the distress of their SCI patients and these misperceptions tend to progressively worsen with length of clinical experience. The present study replicated and extended this tendency amongst research personnel and their SCI subjects. Staff members tended to over-estimate depression, anxiety, and social discomfort while under-estimating the optimism of their SCI subjects. Recommendations are made for the use of a questionnaire to measure their distress. Also, suggestions are made regarding the potential clinical utility of assessing the contrasting perceptions of distress by SCI patients and significant people in their rehabilitation and social environments.

Learned control of coronary blood flow.

Mongrel dogs with chronically implanted electromagnetic flow probes on the left coronary artery were curarized and trained to decrease coronary blood flow in order to avoid and escape from stress. Each of four animals learned to consistently decrease coronary flow with increasing independence from changes in other cardiovascular dynamics. One animal achieved dramatic decreases suggestive of profound coronary vasoconstriction. The results may have important implications for the understanding of ischemic heart disease.