Interarm differences in seated systolic and diastolic blood pressure: the Hypertension Genetic Epidemiology Network study

OBJECTIVE: To examine whether blood pressure (BP) differs between arms in hypertensive siblings and randomly selected volunteers, and whether this difference is explained by cardiovascular risk factors. METHODS: The Hypertension Genetic Epidemiology Network recruited 2395 hypertensive siblings and 854 volunteers. BP was measured six times (three measurements per arm) in seated participants using a Dinamap monitor. The average of three measurements was calculated per arm and the difference taken between arms (i.e. interarm BP differences). RESULTS: The mean age of the subjects was 56 years, and about one-half of the sample was male. More than one-half of the sample was African-American. The mean diastolic BP was equal in the two arms in the random sample (68.8 versus 68.7 mmHg) and in hypertensive siblings (73.4 versus 73.1 mmHg), as was systolic BP (random, 119.6 versus 119.3 mmHg; hypertensives, 130.8 versus 130.7 mmHg). The mean interarm diastolic and systolic BP differences were 2.96 +/- 2.51 and 4.61 +/- 4.10 mmHg, respectively, in the random sample and were 3.09 +/- 2.73 and 5.35 +/- 4.98 mmHg, respectively, in hypertensive siblings. Few (random, 1.6%; hypertensives, 2.8%) had interarm diastolic BP differences > 10 mmHg, but 9.2% of the random sample and 14.2% of hypertensive siblings had systolic BP differences > 10 mmHg. Obesity, higher heart rate, and higher systolic BP were associated with larger interarm BP differences. These results have implications for blood pressure measurement in research settings and in screening programs.     

Interarm blood pressure differences predict target organ damage in type 2 diabetes

Patients with type 2 diabetes mellitus are at high risk for atherosclerotic disease, and proper blood pressure measurement is mandatory. The authors examined the prevalence of an interarm difference (IAD) in blood pressure and its association with cardiovascular risk factors and organ damage (nephropathy, retinopathy, left ventricular hypertrophy, and vascular damage) in a large diabetic population. A total of 800 consecutive patients with type 2 diabetes mellitus were evaluated with an automated simultaneous bilateral device (men: 422 [52.8%]; mean age: 68.1±12.2 years). Diabetic patients with systolic IAD ≥5 and systolic IAD ≥10 mm Hg showed an increased risk of having vascular damage (adjusted odds ratios: 1.73 and 2.49, respectively) and higher pulse pressure. IAD is highly prevalent in patients with diabetes, is associated with vascular damage, even for IAD ≥5 mm Hg, and should be accurately obtained to avoid underdiagnosis and undertreatment of hypertension.     

Neutropenia in human immunodeficiency virus infection: data from the women's interagency HIV study

BACKGROUND: Neutropenia is well described in individuals infected with human immunodeficiency virus (HIV) and occurs in approximately 10% to 50% of cases. Neither the effect of highly active antiretroviral therapy (HAART) on neutrophil counts nor the significance of neutropenia in terms of survival has previously been evaluated. METHODS: The prevalence of neutropenia among 1729 HIV-infected women, followed up as part of the Women's Interagency HIV Study, was evaluated. The CD4 lymphocyte counts, HIV-1 RNA levels, and complete blood cell counts, including absolute neutrophil counts, were obtained at 6-month intervals. RESULTS: Neutropenia was common among HIV-infected women; at baseline, 44% had neutrophil counts less than 2000/microL, whereas 7% had counts less than 1000/microL. During 7.5 years of follow-up, neutrophil counts less than 2000/microL occurred on at least 1 occasion in 79%, whereas absolute neutrophil counts less than 1000/microL were documented in 31%. Worsening HIV disease parameters, such as lower CD4 cell counts (P<.001) and higher HIV-1 RNA levels (P<.001), were associated with development of neutropenia. Resolution of neutropenia was associated with higher CD4 cell counts (P<.001) and use of HAART (P=.007). We found that HAART, without zidovudine, was associated with protection against development of neutropenia. On multivariate analysis, neutropenia was not found to be associated with decreased survival among HIV-infected women. CONCLUSIONS: Worsening HIV disease parameters are associated with neutropenia in HIV-infected women. Treatment with HAART, without zidovudine in the regimen, protects against development of neutropenia, whereas HAART use and higher CD4 cell counts are associated with resolution of neutropenia. Neutropenia is not associated with decreased survival in HIV-infected women.     

Factors associated with incident self-reported AIDS among women enrolled in the women's interagency HIV study (WIHS). WIHS Collaboratorive Study Group

We evaluated factors associated with incident self-reported AIDS diagnoses among HIV-infected women in the Women's Interagency HIV Study (WIHS). Baseline information included age, race/ethnicity, HIV risk category, site of enrollment, years of education, cigarette smoking, CD4 cell count, and HIV viral load. Baseline and follow-up data on self-reported AIDS were analyzed using chi-square, Kaplan-Meier, and Cox proportional hazard models. Among the 1397 HIV-infected women who reported being free of clinical AIDS at baseline, 335 women (24%) reported an incident AIDS diagnosis during follow-up. In stratified Kaplan-Meier analyses, the development of self-reported AIDS was significantly associated with baseline CD4 cell count and viral load (p<0.01). In multivariate Cox proportional hazard analyses, women were statistically more likely to report AIDS if they had CD4 cell counts below 195 cells/mm3 (p<0.01), HIV RNA >4000 copies/ml (p<0.01), were current smokers (p<0.01), and had "no identifiable risk" for acquisition of HIV (p = 0.03). Self-reports of a clinical AIDS diagnosis may not always be accurate, but laboratory markers of HIV disease indicate that those women who self-report such diagnoses have greater immunodeficiency and a higher viral load when compared with those who report no AIDS-defining diagnoses.     

A study of inter-arm blood pressure differences in primary care

OBJECTIVES: To investigate whether there are inter-arm blood pressure differences that are of clinical importance to general practice. DESIGN AND SETTING: Pragmatic study with randomised order of use of left or right arm carried out in routine surgeries in an inner city and suburban general practice. SUBJECTS: There were 237 patients presenting opportunistically for blood pressure measurement to a nurse or general practitioner. MAIN OUTCOME MEASURES: 95% limits of agreement between measurements on the left and right arm and bias between arms. RESULTS: Large inter-arm blood pressure differences exist reflected in wide 95% limits of agreement; -16 mm Hg to 24 mm Hg for the right minus the left arm diastolic blood pressure. There is a small but statistically significant bias to the right arm blood pressure measuring higher than the left (3.7 mm Hg diastolic, 2.4 to 5 mm Hg 95% confidence intervals). An interarm difference of 10 mm Hg or greater for diastolic blood pressure occurred in 40% of subjects and a difference of 20 mm Hg or more for systolic blood pressure occurred in 23% of subjects. CONCLUSIONS: In a primary care setting blood pressure should be measured routinely in both arms. If one arm is to be preferred for pragmatic clinical purposes, then this should be the right arm.     

Gender differences in the regulation of blood pressure

Men are at greater risk for cardiovascular and renal disease than are age-matched, premenopausal women. Recent studies using the technique of 24-hour ambulatory blood pressure monitoring have shown that blood pressure is higher in men than in women at similar ages. After menopause, however, blood pressure increases in women to levels even higher than in men. Hormone replacement therapy in most cases does not significantly reduce blood pressure in postmenopausal women, suggesting that the loss of estrogens may not be the only component involved in the higher blood pressure in women after menopause. In contrast, androgens may decrease only slightly, if at all, in postmenopausal women. In this review the possible mechanisms by which androgens may increase blood pressure are discussed. Findings in animal studies show that there is a blunting of the pressure-natriuresis relationship in male spontaneously hypertensive rats and in ovariectomized female spontaneously hypertensive rats treated chronically with testosterone. The key factor in controlling the pressure-natriuresis relationship is the renin-angiotensin system (RAS). The possibility that androgens increase blood pressure via the RAS is explored, and the possibility that the RAS also promotes oxidative stress leading to production of vasoconstrictor substances and reduction in nitric oxide availability is proposed.     

Sex differences in ambulatory blood pressure monitoring

Purpose

Referral to ambulatory blood pressure monitoring may have bearing upon blood pressure control and prognosis. We describe sex-related differences in referral for ambulatory monitoring and their prognostic impact.

Methods

Between 1991 and 2005, 3957 patients were monitored in our ambulatory monitoring service, of whom 2114 (53%) were women. Demographic and clinical data were analyzed according to sex.

Results

Age (58 ± 15 vs 52 ± 17 years, respectively) and body mass index (27.5 ± 4.9 vs 26.9 ± 4.0 kg/m², respectively) were higher in women than men. Treatment for hypertension was more prevalent in women (62% vs 53%, respectively). Clinic systolic blood pressure (148 ± 24 vs 146 ± 20 mm Hg, respectively) and clinic pulse pressure (65 ± 22 vs 59 ± 18 mm Hg, respectively) were higher in women compared with men. In women, the white-coat effect was increased, compared with men; 5.2 ± 12.4% vs 1.5 ± 10.7% systolic, and 5.4 ± 11.2% vs 3.6 ± 10.3% diastolic. Consequently, women had lower ambulatory blood pressure than men. In women, 24-hour blood pressure was 136 ± 17/76 ± 10 vs 140 ± 15/81 ± 10 mm Hg in men, awake blood pressure 141 ± 17/80 ± 11 vs 144 ± 15/84 ± 10 mm Hg, and sleep blood pressure was 125 ± 19/67 ± 10 vs 127 ± 18/71 ± 11 mm Hg. Age-adjusted ambulatory blood pressure also was lower in women. Ambulatory heart rate was higher in women (P <.0001). Kaplan-Meier survival did not differ by sex (P = .66), despite older age and higher clinic blood pressure.

Conclusions

The results might imply that referral was driven by the physicians' overall patient risk perception. The greater magnitude of white-coat effect in women, and correspondingly lower ambulatory blood pressure, might in part account for similar mortality in the face of older age and higher clinic blood pressure.     

A longitudinal study of ethnic differences in ambulatory blood pressure patterns in youth

BACKGROUND: Many studies demonstrated an ethnic difference in ambulatory blood pressure (BP) patterns. We examined: 1) the stability of this difference; 2) demographic and anthropometric characteristics that predict the difference over 2 years; and 3) the clinical significance of the difference. METHODS: Recordings were performed 2 years apart on 94 African American and 92 European American youths with a positive family history of hypertension, aged 14 +/- 2 years at initial testing. RESULTS: African Americans had higher nighttime systolic BP (SBP) on the initial (109 +/- 9 v 105 +/- 8 mm Hg; P < .001) and follow-up (110 +/- 10 v 105 +/- 8 mm Hg; P < .0001) visits despite similar daytime SBP. This was associated with greater left ventricular mass/height2.7 (LVM/height2.7) during the initial (31 +/- 8 v 28 +/- 6 g/height2.7; P < .01) and follow-up (32 +/- 8 v 28 +/- 8 g/height2.7; P < .02) visits. Sex accounted for 17% (P < .0001) of the variance of follow-up daytime SBP in African Americans, and age for an additional 10% (P < .001). In comparison, initial height accounted for 11% (P < .001) of the variance in European Americans. Sex accounted for 18% (P < .0001) of the variance of follow-up nighttime SBP in African Americans, age for an additional 12% (P < .0001), and initial LVM/height2.7 an additional 6% (P < .02). In contrast, sex accounted for 13% of the variance of follow-up nighttime SBP in European Americans, and initial height accounted for an additional 8% (P < .004). CONCLUSIONS: The pattern of higher nighttime BP despite similar daytime BP in African Americans is stable over time, with sex as the most important predictor of nighttime BP in both groups. This study provides confirmatory data on the clinical significance of the differences.     

Introversion associated with large differences between screening blood pressure and home blood pressure measurement: The Ohasama study

OBJECTIVE: To explore the effect of personality on screening blood pressures measured in clinical settings and home blood pressure measurements. METHODS: From 1997 to 1999, 699 participants underwent screening and home blood pressure measurements and completed the Japanese version of the short-form Eysenck personality questionnaire. An increased screening blood pressure was defined as screening blood pressure > or = 140/90 mmHg and an increased home blood pressure was defined as home blood pressure > or = 135/85 mmHg. RESULTS: Participants with lower extroversion scores (i.e., introversion) showed a greater difference between screening and home systolic blood pressure. The association between introversion and differences was statistically significant, even after adjustment for other possible factors (younger age, female, wide screening pulse pressure, never smoked, and no antihypertensive medication). The adjusted means of SBP differences were 7.3 and 4.4 mmHg among the lowest and highest extroversion quartiles, respectively (P for trend = 0.02). Other personality scores (psychoticism or neuroticism) were not associated with screening and home blood pressure differences. The incorporation of an extroversion score in the basic model consisting of the above factors that affected the difference between screening and home blood pressure slightly improved the prediction of a high home blood pressure. The area under the receiver operating characteristic curve increased by 0.037 among participants with high screening blood pressure and 0.006 for those with normal screening blood pressure compared with the basic model. CONCLUSION: Physicians may need to be aware of 'introverted' patients who have high blood pressure in clinic settings, because they have the potential for 'white-coat' hypertension.     

The relative value of CD4 cell count and quantitative HIV-1 RNA in predicting survival in HIV-1-infected women: results of the women's interagency HIV study.

OBJECTIVES: To determine factors associated with survival and to assess the relative strength of CD4 cell count and HIV-1 RNA in predicting survival in a cohort of HIV-1-infected women. DESIGN: Prospective cohort, enrolled during 1994-1995, with median follow-up of 29 months RESULTS: Of 1769 HIV-infected women 252 died. In multivariate analyses, lower CD4 cell count, higher quantitative plasma HIV-1 RNA, and the presence of a self-reported AIDS-defining (Class C) condition were significantly associated with shorter survival: the relative hazard (RH) of dying was 1.17, 3.27, and 8.46, respectively for women with baseline CD4 cell count of 200-349, 50-199, and < 50 x 10(6) cells/l, compared with women with CD4 cell count of > or = 350 x 10(6) cells/l. Compared with women with HIV-1 RNA levels of < 4000 copies/ml plasma, the RH of dying for women with baseline quantitative HIV-1 RNA measurements of 4000-20,000, 20,000-100,000, 100,000-500,000 and > 500,000 copies/ml, was 2.19, 2.17, 3.16, and 7.25, respectively. CD4 cell count had as strong a prognostic value as HIV-1 RNA level, particularly among participants with more advanced immunodeficiency. When the analysis was adjusted to eliminate the distortion created by having disproportionately sized strata of the categorized variables, the relative hazard of death associated with CD4 cell count became even larger in comparison with that for HIV-1 RNA. Eliminating from the analysis all follow-up time during which participants could have received highly active antiretroviral therapy did not change these findings. Age was not a predictor of survival after adjustment for covariates. CONCLUSIONS: CD4 cell count and HIV-1 RNA had similar prognostic value in this cohort of HIV-1-infected women. Even in the presence of a low viral burden, a substantially decreased CD4 cell count remained a strong predictor of mortality.     

Ethnic differences in blood pressure and hypertensive complications during pregnancy: the Generation R study

The aim was to investigate ethnic differences in blood pressure levels in each trimester of pregnancy and the risk of gestational hypertensive disorders and the degree to which such differences can be explained by education and lifestyle-related factors. The study included 6215 women participating in a population-based prospective cohort study from early pregnancy onward in Rotterdam. Ethnicity was assessed at enrollment. Blood pressure was measured in each trimester. Information about gestational hypertensive disorders was available from medical charts. Lifestyle factors included smoking, alcohol, caffeine intake, folic acid supplementation, sodium and energy intake, body mass index, and maternal stress. Associations and explanatory pathways were investigated using linear and logistic regression analysis. Dutch pregnant women had higher systolic blood pressure levels as compared with women in other ethnic groups in each trimester of pregnancy. Compared with Dutch women, Turkish and Moroccan women had lower diastolic blood pressure levels in each trimester. These differences remained after adjusting for education and lifestyle factors. Turkish and Moroccan women had a lower risk of gestational hypertension as compared with Dutch women (odds ratio, 0.32 [95% CI, 0.18-0.58] and odds ratio, 0.28 [95% CI, 0.14-0.58]), and Cape Verdean women had an elevated risk of preeclampsia (odds ratio, 2.22 [95% CI, 1.22-4.07]). Differences could not be explained by education or lifestyle. Substantial ethnic differences were observed in blood pressure levels and risk of gestational hypertensive disorders in each trimester of pregnancy, and a wide range of variables could not explain these differences.     

Prognostic significance of between-arm blood pressure differences

Blood pressure (BP) recordings often differ between arms, but the extent to which these differences are reproducible and whether the differences have prognostic importance is unknown. We enrolled 421 consecutive patients from a medicine and a renal clinic at a veterans' hospital. Three BP recordings were obtained in each arm using an oscillometric device in a sequential manner and repeated in 1 week. Patients were followed for all-cause mortality 相似文献   

Ethnic differences in sleep quality accompany ethnic differences in night-time blood pressure dipping

BACKGROUND: African Americans exhibit a smaller nocturnal decrease in blood pressure (BP) than whites, and there are also reports of poorer sleep quality among African Americans. We examined the contribution of sleep quality to ethnic differences in BP dipping in African American and white male and female college students. We hypothesized that African Americans would exhibit blunted nocturnal BP dipping compared to whites, which would be partly accounted for by poorer sleep quality among African Americans. METHODS: Forty-three African American and 46 white college students aged 18 to 25 years completed an ambulatory BP protocol that included wrist actigraphy, which was used in conjunction with participant self-reports of sleep times for analyses of sleep quality. RESULTS: Although daytime and night-time BP did not differ according to ethnicity, African Americans had a smaller dip in systolic BP (P < .01), and African American women had a smaller dip in diastolic BP than whites (P < .01). Whites were more likely to be classified as a dipper (71%) than African Americans (41%) (P < .01). African Americans, compared to whites, spent less time in bed, were asleep for a shorter period of time, took longer to fall asleep, exhibited poorer sleep efficiency, and were awakened a higher percentage of the time by the inflation of the BP cuff (F > or = 4.85, P < .05). However, sleep quality did not appear to contribute to ethnic differences in diastolic BP dipping. CONCLUSIONS: Sleep quality accompanied ethnic differences in systolic and diastolic BP dipping, but did not account for these differences.     

Ethnic differences in the association of birth weight and blood pressure: the Georgia cardiovascular twin study

BACKGROUND: African Americans (AAs) not only have higher blood-pressure levels, but also an increased risk of low weight at birth, compared with European Americans (EAs). In light of fetal programming theories, it has been suggested that ethnic differences in blood pressure originate in utero. However, most previous studies in biethnic samples have not found a significant inverse association between birth weight and blood pressure in AAs. METHODS: In 562 EA and 465 AA adolescent twins of the Georgia Cardiovascular Twin Study, we investigated the potential ethnic difference in the association of blood pressure and birth weight, with the ability to control for potential confounding by familial factors. RESULTS: Blood-pressure levels were significantly higher in AAs compared to EAs, independent of birth weight (P < .01). After adjustment for parental factors and body mass index, the difference in systolic blood pressure per kg birth weight was -1.1 mm Hg (95% confidence interval, -2.7 to 0.48, P = .17) in EAs, and -2.5 mm Hg (95% confidence interval, -4.7 to -0.40, P = .02) in AAs. A significant ethnic interaction was revealed in paired analysis, where the inverse association remained in AAs, but not in EAs. Associations with diastolic blood pressure were generally weaker and nonsignificant. CONCLUSIONS: We showed that low birth weight was associated with an elevated systolic blood pressure in AAs, independent of familial factors. The results also suggest that the association between birth weight and blood pressure may be more pronounced in AAs in adolescence.     

Racial differences in ambulatory blood pressure monitoring-derived 24 h patterns of blood pressure in adolescents.

BACKGROUND: Many pathologic conditions are characterized by a blunted nocturnal decline in blood pressure. OBJECTIVE: To review the evidence that African Americans display a similar pattern and examine factors associated with the pattern. METHOD: We reviewed published racial comparisons of patterns of ambulatory blood pressure in adults and youths. RESULTS: Authors of 15 studies reported finding blunted nocturnal declines in African Americans and authors of two studies did not. Authors of studies of Africans in Africa and of blacks from other countries reported normal nocturnal declines. Both intake of sodium and indexes of body size have been related to nocturnal blood pressure in African-American youths. This pattern is related to greater than normal target-organ changes. CONCLUSION:; We conclude that the race of a patient should be considered when evaluating a 24h pattern of blood pressure in an adolescent; and the blunted nocturnal decline displayed by many African-American adolescents is the result of a gene-environment interaction and therefore is susceptible to modification through changes in diet, level of activity, and other environmental factors.