Pulse pressure and mean arterial pressure in relation to ischemic stroke among patients with uncontrolled hypertension in rural areas of China

Prevalence of elevated mean arterial pressure and how fitness moderates its association with BMI in youth

OBJECTIVE

Cardiorespiratory fitness is known to be cardioprotective and its association with the components of the metabolic syndrome in children is becoming clearer. The aim of the present study was to examine the extent to which cardiorespiratory fitness may offset the weight-related association with mean arterial pressure (MAP) in schoolchildren.

DESIGN

Cross-sectional study.

SETTINGS

Schoolchildren from the East of England, U.K.

SUBJECTS

A total of 5983 (48% females) schoolchildren, 10 to 16 years of age, had height, weight and blood pressure measured by standard procedures and cardiorespiratory fitness assessed by the 20 m shuttle-run test. Participants were classified as fit or unfit using internationally accepted fitness cut-off points; and as normal weight, overweight or obese based on BMI, again using international cut-off points. Age-adjusted ANCOVA was used to determine the main effects and interaction of fitness and BMI on MAP Z-score. Logistic regression models were used to estimate odds ratios of elevated MAP.

RESULTS

Prevalence of elevated MAP in schoolchildren was 14.8% overall and 35.7% in those who were obese-unfit. Approximately 21% of participants were overweight and 5% obese, while 23% were classified as unfit. MAP generally increased across BMI categories and was higher in the aerobically unfit participants. Obese-fit males had lower MAP compared with obese-unfit males (P < 0.001); this trend was similar in females (P = 0.05).

CONCLUSIONS

Increasing fitness level may have a positive impact on the weight-related elevations of MAP seen in obese and overweight schoolchildren.

Neuropeptide Y promoter polymorphism modifies effects of a weight-loss diet on 2-year changes of blood pressure: the preventing overweight using novel dietary strategies trial

Neuropeptide Y (NPY) is implicated in the regulation of blood pressure (BP), and NPY pathways in the hypothalamus are sensitive to dietary fat. We evaluated the potential effect of a functional variant rs16147 located in the NPY gene promoter region on the association between 2-year diet intervention and change in multiple BP measures in the randomized Preventing Overweight Using Novel Dietary Strategies Trial. The NPY rs16147 was genotyped in 723 obese adults who were randomly assigned to 1 of 4 diets differing in the target percentages of energy derived from fat, protein, and carbohydrate. The changes of 4 BP phenotypes, including systolic BP, diastolic BP, pulse pressure, and mean arterial pressure, during 2-year diet intervention were analyzed. In the total participants and participants with hypertension, we observed significant and consistent interactions between rs16147 genotype and dietary fat intake on changes in multiple BP phenotypes at 2 years (all P for interactions <0.05). The risk allele (C allele) was associated with a greater reduction of BP phenotypes in response to low-fat diet, whereas an opposite genetic effect was observed in response to high-fat diet. In addition, the C allele was related to greater changes in 4 BP phenotypes in hypertensive compared with nonhypertensive participants. Our data suggest that NPY rs16147 may modulate the association between dietary fat intake and changes in BP phenotypes, and the C allele exerts a long-term beneficial effect on lowering BP in response to low-fat diet in obese and hypertensive subjects.

Uric acid is an important predictor for hypertensive early atherosclerosis

INTRODUCTION

The association between hyperuricemia and cardiovascular disease in hypertensive subjects is controversial. Attempts to elucidate the possible association between hyperuricemia and early atherosclerosis in hypertensive patients may provide alternative prevention or therapy targets for future cardiovascular events.

METHODS

A total of 67 hypertensive and 30 healthy subjects underwent B-mode ultrasonography to measure carotid intima media thickness (C-IMT). All biochemical analyses were assessed by local laboratories using standard laboratory methods.

RESULTS

C-IMT, serum uric acid (UA) levels, and mean arterial blood pressure (MBP) levels were significantly higher in hypertensive population compared to healthy subjects (P<0.001). Among hypertensive subjects, high sensitivity C-reactive protein (hs-CRP), C-IMT, and proteinuria levels were significantly higher in hyperuricemic patients compared to normouricemic participants (for all, P<0.05). Age (r=0.28, P=0.02), MBP (r=0.34, P=0.04), hs-CRP (r=0.58, P=0.006), proteinuria (r=0.58, P=0.007), estimated glomerular filtration rate (r=-0.35, P=0.02), and UA (r=0.31, P=0.02) levels were significantly associated with C-IMT levels. Multiple linear regression analysis using C-IMT as a dependent variable showed that age (beta=0.84, P=0.03) and UA levels (beta=-0.87, P=0.02) were independently associated with C-IMT.

CONCLUSION

Hyperuricemia is an independent predictor for early atherosclerosis in hypertensive subjects with normal renal function. Therefore, the optimal control of UA may provide further benefits in preventing atherosclerosis and hypertensive end-organ injury.

Decreased glomerular filtration rate is associated with mortality and cardiovascular events in patients with hypertension: a prospective study

Background

Few studies reported the associations between decreased glomerular filtration rate (GFR) and mortality, coronary heart disease (CHD), and stroke in hypertensive patients. We aim to assess the associations between GFR and mortality, CHD, and stroke in hypertensive patients and to evaluate whether low GFR can improve the prediction of these outcomes in addition to conventional cardiovascular risk factors.

Methods and Findings

This is an observational prospective study and 3,711 eligible hypertensive patients aged ≥5 years from rural areas of China were used for the present analysis. The associations between eGFR and outcomes, followed by a median of 4.9 years, were evaluated using Cox proportional hazards models adjusting for other potential confounders. Low eGFR was independently associated with risk of all-cause mortality, cardiovascular mortality, and incident stroke [multivariable adjusted hazard ratios (95% confidence intervals) for eGFR <60 ml/min/1.73 m² relative to eGFR ≥90 ml/min/1.73 m² were 1.824 (1.047–3.365), 2.371 (1.109–5.068), and 2.493 (1.193–5.212), respectively]. We found no independent association between eGFR and the risk of CHD. For 4-year all-cause and cardiovascular mortality, integrated discrimination improvement (IDI) was positive when eGFR were added to traditional risk factors (1.51%, P = 0.016, and 1.99%, P = 0.017, respectively). For stroke and CHD events, net reclassification improvements (NRI) were 5.9% (P = 0.012) and 1.8% (P = 0.083) for eGFR, respectively.

Conclusions

We have established an inversely independent association between eGFR and all-cause mortality, cardiovascular mortality, and stroke in hypertensive patients in rural areas of China. Further, addition of eGFR significantly improved the prediction of 4-year mortality and stroke over and above that of conventional risk factors. We recommend that eGFR be incorporated into prognostic assessment for patients with hypertension in rural areas of China.

Limitations

We did not have sufficient information on atrial fibrillation to control for the potential covariate. These associations should be further confirmed in future.

The relationship between serum uric acid and spirometric values in participants in a health check: the Takahata study

BACKGROUND

Tissue hypoxia induces the degradation of adenosine triphosphate, resulting in the production of uric acid (UA). Patients with chronic obstructive pulmonary disease (COPD) have been reported to have high serum levels of UA (sUA), compared with control subjects. However, the relationship between sUA levels and spirometric measures has not been investigated in detail in a general population.

METHODS

Subjects aged 40 years or older (n = 2,917), who had participated in a community-based annual health check in Takahata, Japan, in 2004 and 2005, were enrolled in the study. These subjects performed spirometry, their blood pressure was measured, and a blood sample was taken.

RESULTS

sUA levels were significantly higher in males than in females. Percent predicted forced vital capacity [FVC %predicted] (r = -0.13) and forced expiratory volume in 1 s [FEV(1) %predicted] (r = -0.118) were inversely correlated with sUA levels in females but not in males. Univariate regression analysis indicated that age, body mass index (BMI), ethanol intake, mean blood pressure (BP), and serum creatinine (sCr) were significantly associated with sUA levels in males. In females, age, BMI, mean BP, hemoglobin A1c, sCr, FVC %predicted, and FEV(1) %predicted were significantly associated with sUA levels. Multiple linear regression analysis showed that for both genders, FVC %predicted and FEV(1) %predicted were predictive for sUA levels, independently of the other clinical parameters. Subjects with lung restriction had higher sUA levels than subjects without lung restriction. In addition, subjects with moderate and severe airflow limitation had higher sUA levels than subjects without airflow limitation or those with mild airflow limitation.

CONCLUSION

FVC %predicted and FEV(1) %predicted were significantly associated with sUA levels in a general population.

Blood pressure re-screening for healthy adults: what is the best measure and interval?

Blood pressure (BP) screening is important to identify those at risk of cardiovascular disease, but there has been little data on the appropriate interval of screening. We aimed to evaluate the optimal interval and the best measure for BP re-screening by estimating the long-term, true change variance ('signal') and short-term, within-person variance ('noise'). Study design was a cohort study from 2005 to 2008. Target population was Japanese healthy adults not taking antihypertensive medication at baseline, in a teaching hospital. We measured annually the systolic BP (SBP) and the diastolic BP (DBP), and calculated the pulse pressure (PP) and the mean arterial pressure (MAP). A total of 15,055 individuals (51% male) with a mean age of 49 years had annual check-ups. Short-term coefficient of variation was lowest for MAP at 5.2%, followed by SBP (5.7%) and DBP (5.8%), and highest for PP (12%). After 3 years, the 'signal' of true BP changes of only SBP and MAP equaled the 'noise' of BP measurement; however, it was larger for those with higher initial BPs. SBP or MAP appears to be a better screening measure. The optimal interval should be 3 years or more, with SBP<130 mm Hg and 2 years for those with SBP ≥ 130 mm Hg.

The International Fitness Scale (IFIS): usefulness of self-reported fitness in youth

BACKGROUND

We examined: (i) the usefulness of the International Fitness Scale (IFIS) to correctly rank adolescents into physical fitness levels; (ii) the capacity of the IFIS for predicting cardiovascular disease (CVD) risk; and (iii) the reliability of the IFIS in adolescents.

METHODS

The study comprised 3059 adolescents (aged 12.5-17.5 years) from nine European countries (HELENA study). Blood samples were collected in one-third of the participants (randomly selected, n = 981). Test-retest reliability of the IFIS was studied in a separate sample of 277 adolescents. Physical fitness-cardiorespiratory fitness (CRF), muscular fitness (MF), speed-agility (SP-AG), flexibility and overall fitness-was self-reported using 5-point Likert-scale questions (1 = very poor, 5 = very good) and measured using standard field-based tests. The CVD risk factors measured included total/central adiposity indices and mean arterial pressure, total and high density lipoprotein cholesterol, triglycerides, insulin resistance (HOMA) and C-reactive protein.

RESULTS

Analysis of covariance showed that adolescents reporting better fitness had higher measured fitness levels for all the variables studied (all P < 0.001), regardless of gender, age and weight status. Adolescents reporting very good overall fitness, CRF and SP-AG had a healthier cardiovascular profile in eight out of nine CVD risk factors studied. Perfect agreement (same test-retest answer) was observed in 65% of the adolescents and perfect-acceptable agreement (same answer or ±1) in 97% of the adolescents.

CONCLUSIONS

(i) The IFIS is able to correctly rank adolescents according to their measured physical fitness levels; (ii) adolescents reporting a good/very good overall fitness, CRF or SP-AG have a more favorable cardiovascular profile; and (iii) The IFIS is reliable in adolescents.

Ankle blood pressure and pulse pressure as predictors of cerebrovascular morbidity and mortality in a prospective follow-up study

Background and Objective. We examined the association of elevated ankle blood pressure (ABP), together with exercise blood pressure, with incident cerebrovascular (CV) morbidity and mortality in a prospective follow-up study of 3,808 patients. The results were compared with pulse pressure, another indicator of arterial stiffness. Methods. Patients with normal ankle and exercise brachial blood pressures were taken as the reference group. Pulse pressure was considered as quartiles with the lowest quartile as the reference category. Results. A total of 170 subjects had a CV event during the follow-up. Multivariate adjusted hazard ratio of a CV event was 2.24 (95% CI 1.43–3.52, P < .0001) in patients with abnormal ABP. The pulse pressure was significant only in the model adjusted for age and sex. Conclusion. The risk of a future CV event was elevated already in those patients among whom elevated ABP was the only abnormal finding. As a risk marker, ABP is superior to the pulse pressure.

Profile and predictor of health-related quality of life among hypertensive patients in south-western Nigeria

Background

The health-related quality of life (HRQOL) of hypertensives may be influenced by blood pressure, adverse effects of drugs used to treat hypertension, or other factors, such as the labelling effect, or beliefs and attitudes about illness and treatment. There is paucity of information on the determinants of HRQOL among black hypertensives especially in the developing countries such as Nigeria. This study describes the HRQOL and its determinants among black patients diagnosed and treated for Hypertension in Nigeria.

Methods

The study was a cross sectional in design that involved 265 hypertensive patients receiving treatment at the medical outpatient unit of the Federal Medical Centre Abeokuta, Nigeria. They were all consecutive patients that presented at the hospital during the period of the study who meet the inclusion criteria and consented to participate in the study. Demographic data, disease characteristics such as symptoms and signs and recent drug history were obtained from the patients and their hospital records as documented by the physician. The SF-36 questionnaire was administered once by interview to the participants to measure their HRQOL. Descriptive statistics was used in summarizing the demographic data and hypertension related histories of the participants. Multiple linear regression was used to model for the influence of socio demographic and clinical variables of the hypertensives on their HRQOL.

Results

Physical functioning domain mean score was far below average (33.53 ± 29.65). Role physical and role emotional domains were a little above average (54.7 ± 40.4, 51.1 ± 40.6 respectively). Role Physical (p = 0.043), Role Emotional (p = 0.003), Vitality (p = 0.014) and Mental Health (p = 0.034) domain mean scores for patients with controlled BP were significantly higher than patients with uncontrolled BP. The overall HRQOL was significantly better in the group of hypertensives with controlled blood pressure (p = 0.014). Increasing blood pressure (p = 0.005) and symptom count (p < 0.001), the presence of stroke (p = 0.008) and visual impairment (p = 0.015) were significant negative predictors of the overall HRQOL.

Conclusion

This study provides evidence for a model that links patients' status with regard to biology (blood pressure), symptoms, and functionality (HRQOL) and may prove useful in guiding follow-up of patients who receive treatment for hypertension. Identification of patient's symptoms, blood pressure, complication/comorbidity and changes in functioning may help clinicians increase their effectiveness in helping patients maintain adherent behaviour with drug and non drug interventions in chronic diseases such as hypertension.