Association of early childhood abdominal circumference and weight gain with blood pressure at 36 months of age: secondary analysis of data from a prospective cohort study

To assess whether changes in measures of fat distribution and body size during early life are associated with blood pressure at 36 months of age.

Breaking up prolonged sitting reduces resting blood pressure in overweight/obese adults

To compare the effect of 7 h of prolonged sitting on resting blood pressure with a similar duration of sitting combined with intermittent brief bouts of light-intensity or moderate-intensity physical activity.

Classification of electrocardiogram and auscultatory blood pressure signals using machine learning models

In this paper, two real-world medical classification problems using electrocardiogram (ECG) and auscultatory blood pressure (Korotkoff) signals are examined. A total of nine machine learning models are applied to perform classification of the medical data sets. A number of useful performance metrics which include accuracy, sensitivity, specificity, as well as the area under the receiver operating characteristic curve are computed. In addition to the original data sets, noisy data sets are generated to evaluate the robustness of the classifiers against noise. The 10-fold cross validation method is used to compute the performance statistics, in order to ensure statistically reliable results pertaining to classification of the ECG and Korotkoff signals are produced. The outcomes indicate that while logistic regression models perform the best with the original data set, ensemble machine learning models achieve good accuracy rates with noisy data sets.

Corticomotor excitability is increased following an acute bout of blood flow restriction resistance exercise

We used transcranial magnetic stimulation (TMS) to investigate whether an acute bout of resistance exercise with blood flow restriction (BFR) stimulated changes in corticomotor excitability (motor evoked potential, MEP) and short-interval intracortical inhibition (SICI), and compared the responses to two traditional resistance exercise methods. Ten males completed four unilateral elbow flexion exercise trials in a balanced, randomized crossover design: (1) heavy-load (HL: 80% one-repetition maximum [1-RM]); (2) light-load (LL; 20% 1-RM) and two other light-load trials with BFR applied; (3) continuously at 80% resting systolic blood pressure (BFR-C); or (4) intermittently at 130% resting systolic blood pressure (BFR-I). MEP amplitude and SICI were measured using TMS at baseline, and at four time-points over a 60 min post-exercise period. MEP amplitude increased rapidly (within 5 min post-exercise) for BFR-C and remained elevated for 60 min post-exercise compared with all other trials. MEP amplitudes increased for up to 20 and 40 min for LL and BFR-I, respectively. These findings provide evidence that BFR resistance exercise can modulate corticomotor excitability, possibly due to altered sensory feedback via group III and IV afferents. This response may be an acute indication of neuromuscular adaptations that underpin changes in muscle strength following a BFR resistance training programme.

Impact of nurse-mediated management on achieving blood pressure goal levels in primary care: insights from the Valsartan intensified primary carE reduction of blood pressure study

BACKGROUND: Blood pressure targets in individuals treated for hypertension in primary care remain difficult to attain.

AIMS: To assess the role of practice nurses in facilitating intensive and structured management to achieve ideal BP levels.

METHODS: We analysed outcome data from the Valsartan Intensified Primary carE Reduction of Blood Pressure Study. Patients were randomly allocated (2:1) to the study intervention or usual care. Within both groups, a practice nurse mediated the management of blood pressure for 439 patients with endpoint blood pressure data (n=1492). Patient management was categorised as: standard usual care (n=348, 23.3%); practice nurse-mediated usual care (n=156, 10.5%); standard intervention (n=705, 47.3%) and practice nurse-mediated intervention (n=283, 19.0%). Blood pressure goal attainment at 26-week follow-up was then compared.

RESULTS: Mean age was 59.3±12.0 years and 62% were men. Baseline blood pressure was similar in practice nurse-mediated (usual care or intervention) and standard care management patients (150 ± 16/88 ± 11 vs. 150 ± 17/89 ± 11 mmHg, respectively). Practice nurse-mediated patients had a stricter blood pressure goal of ⩽125/75 mmHg (33.7% vs. 27.3%, p=0.026). Practice nurse-mediated intervention patients achieved the greatest blood pressure falls and the highest level of blood pressure goal attainment (39.2%) compared with standard intervention (35.0%), practice nurse-mediated usual care (32.1%) and standard usual care (25.3%; p<0.001). Practice nurse-mediated intervention patients were almost two-fold more likely to achieve their blood pressure goal compared with standard usual care patients (adjusted odds ratio 1.92, 95% confidence interval 1.32 to 2.78; p=0.001).

CONCLUSION: There is greater potential to achieve blood pressure targets in primary care with practice nurse-mediated hypertension management.

Characterising the extent of misreporting of high blood pressure, high cholesterol, and diabetes using the Australian Health Survey

BACKGROUND: Measuring and monitoring the true prevalence of risk factors for chronic conditions is essential for evidence-based policy and health service planning. Understanding the prevalence of risk factors for cardiovascular disease (CVD) in Australia relies heavily on self-report measures from surveys, such as the triennial National Health Survey. However, international evidence suggests that self-reported data may substantially underestimate actual risk factor prevalence. This study sought to characterise the extent of misreporting in a large, nationally-representative health survey that included objective measures of clinical risk factors for CVD.

METHODS: This study employed a cross-sectional analysis of 7269 adults aged 18 years and over who provided fasting blood samples as part of the 2011-12 Australian Health Survey. Self-reported prevalence of high blood pressure, high cholesterol and diabetes was compared to measured prevalence, and univariate and multivariate logistic regression analyses identified socio-demographic characteristics associated with underreporting for each risk factor.

RESULTS: Approximately 16 % of the total sample underreported high blood pressure (measured to be at high risk but didn't report a diagnosis), 33 % underreported high cholesterol, and 1.3 % underreported diabetes. Among those measured to be at high risk, 68 % did not report a diagnosis for high blood pressure, nor did 89 % of people with high cholesterol and 29 % of people with high fasting plasma glucose. Younger age was associated with underreporting high blood pressure and high cholesterol, while lower area-level disadvantage and higher income were associated with underreporting diabetes.

CONCLUSIONS: Underreporting has important implications for CVD risk factor surveillance, policy planning and decisions, and clinical best-practice guidelines. This analysis highlights concerns about the reach of primary prevention efforts in certain groups and implications for patients who may be unaware of their disease risk status.

Origin of aberrant blood pressure and sympathetic regulation in diet-induced obesity

High fat diet (HFD)-induced hypertension in rabbits is neurogenic and caused by the central action of leptin, which is thought to be dependent on activation of α-melanocortin-stimulating hormone (α-MSH) and neuropeptide Y-positive neurons projecting to the dorsomedial hypothalamus (DMH) and ventromedial hypothalamus (VMH). However, leptin may act directly in these nuclei. Here, we assessed the contribution of leptin, α-MSH, and neuropeptide Y signaling in the DMH and VMH to diet-induced hypertension. Male New Zealand white rabbits were instrumented with a cannula for drug injections into the DMH or VMH and a renal sympathetic nerve activity (RSNA) electrode. After 3 weeks of an HFD (13.3% fat; n=19), rabbits exhibited higher RSNA, mean arterial pressure (MAP), and heart rate compared with control diet-fed animals (4.2% fat; n=15). Intra-VMH injections of a leptin receptor antagonist or SHU9119, a melanocortin 3/4 receptor antagonist, decreased MAP, heart rate, and RSNA compared with vehicle in HFD rabbits (P<0.05) but not in control diet-fed animals. By contrast, α-MSH or neuropeptide Y injected into the VMH had no effect on MAP but produced sympathoexcitation in HFD rabbits (P<0.05) but not in control diet-fed rabbits. The effects of the leptin antagonist, α-MSH, or neuropeptide Y injections into the DMH on MAP or RSNA of HFD rabbits were not different from those after vehicle injection. α-MSH into the DMH of control diet-fed animals did increase MAP, heart rate, and RSNA. We conclude that the VMH is the likely origin of leptin-mediated sympathoexcitation and α-MSH hypersensitivity that contribute to obesity-related hypertension.

Coronary angiography observations: evidence-based or ritualistic practice?

Objective: The purposes of this study were to describe the incidence and occurrence of femoral artery bleeding during the first 6 hours after coronary angiography and to determine whether there is a relationship between  current postangiogram observation protocols and the detection of  complications.

Design: This was a prospective descriptive study.

Setting: The study was conducted in 3 university hospitals in Melbourne, Australia.

Patients: Subjects included 55 patients representing the complication rate of 1075 patients, mean age 61 years (SD, 12), 69% male.

Results: About 5.1% of patients had 1 or more incidents of bleeding  requiring manual compression. In 4.2% of patients, bleeding occurred within 6 hours of angiography. Bleeding occurred a median of 2.02 hours (Q1 = 45 minutes, Q3 = 4.31 hours) after angiography. Patients without pressure bandaging bled a median of 1.32 hours (Q1 = 36.50 minutes, Q3 = 2.59 hours) after angiography. Patients with pressure bandaging bled a median of 4.75 hours (Q1 = 2.25 hours, Q3 = 7.28 hours) after angiography. In 40.6% of cases, bleeding was detected through the patient’s call for assistance, and in 59.4% of cases nurses noted bleeding while checking the puncture site. Postcatheter observations were recorded 23.70 (SD, 14.60) minutes before the bleeding incident. There were no significant changes in vital signs, systolic blood pressure (P > .05), diastolic blood pressure (P > .05), or pulse (P > .05) before or during a bleeding episode. All were within normal parameters. No neurovascular assessment anomalies were detected.

Conclusion: The use of pressure bandaging has a significant effect on the incidence and pattern of bleeding. Routine vital sign measurement has no relevance in detecting local complications after angiography. The most significant complication is bleeding that requires manual compression. Detection is through frequent puncture site observation and patient recognition and communication.

Benefits of a year-long workplace weight loss program on cardiovascular risk factors

Objective: To assess the effectiveness of a year-long workplace weight loss program in reducing risk factors of coronary heart disease.

Design: A randomised, controlled study of low fat (25% of dietary energy) diet- and/or moderate exercise-induced weight loss interventions in free-living, middle-aged men. Compliance was monitored from food and activity diaries at monthly blood pressure measurement sessions. Blood was sampled and body composition determined from dual energy X-ray absorptiometry before and after 12 months.

Subjects and setting: Fifty-eight overweight men (mean [+ or -] SD age: 43.4 [+ or -] 5.7 years; BMI 29.0 [+ or -] 2.6 kg/[m.sup.2]), recruited from a national corporation, were instructed into diet (n = 18) exercise (a 21) or control (n = 19) groups over 12 months; 16 control subjects combined diet and exercise (n = 16) for the subsequent 12 months.

Main outcome measures: At 12 months, weight, total and regional fat and lean mass, dietary energy and percentage dietary fat intake, physical activity indices, systolic and diastolic blood pressure, serum insulin, blood lipids and lipoproteins.

Statistical analyses: Differences between groups were tested using analysis of variance with Scheffe post hoc test. Differences between pre- and post-intervention variables were tested using Students' paired t-tests. Pearson's correlation coefficient and univariate linear regression identified association between dependent variables, multiple stepwise regression identified specific predictors.

Results: Weight loss with either diet or exercise resulted in a reduction in systolic blood pressure (-3.3 [+ or -] 1.7%), diastolic blood pressure (-4.8 [+ or -] 1.3%) and LDL cholesterol (-3.9 [+ or -] 2.8%), a rise in HDL cholesterol (+10.0 [+ or -] 3.8%) and a change in the LDL/HDL ratio (-8.9 [+ or -] 3.5%). Abdominal fat loss (-26.8 [+ or -] 3.6% after diet; -16.6 [+ or -] 4.5% after exercise; -21.0 [+ or -] 4.7% after diet and exercise) was the strongest predictor of change in blood pressure: twenty percent abdominal fat loss predicted a percentage fall of 2.4 [+ or -] 0.05% in systolic blood pressure and 5.4 [+ or -] 0.07% in diastolic blood pressure. Greater abdominal fat loss was associated with the greatest decrease in serum insulin (P < 0.05).

Conclusion: Modest changes in diet and exercise effected by a low cost workplace-based education program achieved weight loss, loss of abdominal fat, reduced blood pressure and serum insulin and improved blood lipid concentrations. (Nutr Diet 2002;59:87-96)

Long-term effects of a reduced fat diet intervention on cardiovascular disease risk factors in individuals with glucose intolerance

The long-term effects on cardiovascular disease risk factors of a reduced fat (RF), ad libitum diet were compared with usual diet (control, CD) in glucose intolerance individuals.

Participants were 136 adults aged ≥40 years with ‘glucose intolerance’ (2 h blood glucose 7–11.0 mmol/l) detected at a Diabetes Survey who completed at 1 year intervention study of reduced fat, ad libitum diet versus usual diet. They were re-assessed at 2, 3 and 5 years. Main outcome measures were blood pressure, serum concentrations of total cholesterol, HDL and LDL cholesterol, total cholesterol:HDL ratio, triglycerides and body weight.

The reduced fat diet lowered total cholesterol (P<0.01), LDL cholesterol (P≤0.05), total cholesterol:HDL ratio (P≤0.05), body weight (P<0.01) and systolic blood pressure (P≤0.05) initially and diastolic blood pressure (P<0.01) long-term. No significant changes occurred in HDL cholesterol or triglycerides. In the more compliant 50% of the intervention group, systolic and diastolic blood pressure levels and body weight were lower at 1, 2 and 3 years (P<0.05).

It was concluded that a reduced fat ad libitum diet has short-term benefits for cholesterol, body weight and systolic blood pressure and long-term benefits for diastolic blood pressure without significantly effecting HDL cholesterol and triglycerides despite participants regaining their lost weight.

Interrelationship between anxiety, lifestyle self-reports and fitness in a sample of Hong Kong University students

Although anxiety in university students has been well documented, the influence of lifestyle and fitness status in relation to anxiety has not been investigated from a cultural perspective previously. To make recommendations regarding the avoidance or management of anxiety in this anxiety-prone cohort that are rationally based, this preliminary investigation examined the interrelationship between anxiety, lifestyle self-reports and aerobic fitness in Hong Kong Chinese University students. The State Trait Anxiety Inventory (Form Y-2) and a lifestyle questionnaire were completed by 213 students. Female students were more anxious than male students. Subjects with high anxiety reported more deleterious lifestyle behaviours including higher salt consumption and lower levels of exercise; in addition to more frequent symptoms of anxiety such as headaches and daytime somnolence. The extremes of this sample were stratified into a low anxiety group ( n =17) and a high anxiety group ( n =14) to compare their fitness status. Although both groups had below normal aerobic capacity, the higher systolic blood pressure observed for the high anxiety group is consistent with signs of anxiety, or greater deconditioning in this group or both. The results of this study have highlighted anxiety as a concern in Hong Kong University students and identified some lifestyle and fitness correlates. Understanding lifestyle and pathophysiological correlates of anxiety in Hong Kong University students that may have a cultural basis, is a crucial step toward averting or managing anxiety when these students are studying either in Hong Kong or abroad.

Changing risk behaviours for non-communicable disease in New Zealand working men - is workplace intervention effective?

Aims. To evaluate the effectiveness of a health promotion
programme targeting dietary behaviours and physical
activity among male hourly-paid workers and to explore
demographic and attitudinal influences on dietary patterns
at baseline.
Methods. A controlled field trial compared workers at one
intervention and one control worksite. The intervention
comprised nutrition displays in the cafeteria and monthly
30-minute workshops for six months. Key outcome
measures at six and twelve-months were self-reported
dietary and lifestyle behaviours, nutrition knowledge, body
mass index (BMI), waist circumference and blood pressure.
Results. 132 men at the intervention site and 121 men at the
control site participated in the study and a high retention rate
(94% at 6-months and 89% at 12-months) was achieved. At
baseline, 40% of the total sample (253) were obese, 30% had
elevated blood pressure, 59% indicated an excessive fat intake
and 92% did not meet the recommended vegetable and fruit
intake. The intervention reduced fat intake, increased
vegetable intake and physical activity, improved nutrition
knowledge and reduced systolic blood pressure when
compared to the control site. There was no difference in
change in mean BMI or waist circumference. Reduction in
BMI was associated with reduction in fat intake.
Discussion. Low intensity workplace intervention can
significantly improve reported health behaviours and
nutrition knowledge although the impact on more
objective measures of risk was variable. A longer duration
or more intensive intervention may be required to achieve
further reduction in risk factors.

An index of diet and eating patterns is a valid measure of diet quality in an Australian population

Diet indices represent an integrated approach to assessing eating patterns and behaviors. The aim of this study was to develop a comprehensive food-based dietary index to reflect adherence to healthy eating recommendations, evaluate the construct validity of the index using nutrient intakes, and evaluate this index in relation to sociodemographic factors, health behaviors, risk factors, and self-assessed health status. Data were analyzed from adult participants of the Australian National Nutrition Survey who completed a 108-item FFQ and a food habits questionnaire (n = 8220). The dietary guideline index (DGI) consisted of 15 items reflecting the dietary guidelines, including dietary indicators of vegetables and legumes, fruit, total cereals, meat and alternatives, total dairy, beverages, sodium, saturated fat, alcoholic beverages, and added sugars. Diet quality was incorporated using indicators relating to whole-grain cereals, lean meat, reduced/low fat dairy, and dietary variety. We investigated associations between the DGI score, sociodemographic factors, health behaviors, chronic disease risk factors, and nutrient intakes. We found associations between the DGI scores and sex, age, income, area-level socioeconomic disadvantage, smoking, physical activity, waist:hip ratio, systolic blood pressure (males only), and self-assessed health status (females only) (all P < 0.05). Higher DGI scores were associated with lower intakes of energy, total fat, and saturated fat and higher intakes of fiber, β-carotene, vitamin C, folate, calcium, and iron (P < 0.05). This food-based dietary index is able to discriminate across a variety of sociodemographic factors, health behaviors, and self-assessed health and reflects intakes of key nutrients.

Television time and continuous metabolic risk in physically active adults

Purpose: Among Australian adults who met the public health guideline for the minimum health-enhancing levels of physical activity, we examined the dose-response associations of television-viewing time with continuous metabolic risk variables.

Methods: Data were analyzed on 2031 men and 2033 women aged >= 25 yr from the 1999-2000 Australian Diabetes, Obesity and Lifestyle study without clinically diagnosed diabetes or heart disease, who reported at least 2.5 h·wk-1 of moderate- to vigorous-intensity physical activity. Waist circumference, resting blood pressure, and fasting and 2-h plasma glucose, triglycerides, and high-density-lipoprotein cholesterol (HDL-C) were measured. The cross-sectional associations of these metabolic variables with quartiles and hours per day of self-reported television-viewing time were examined separately for men and for women. Analyses were adjusted for age, education, income, smoking, diet quality, alcohol intake, parental history of diabetes, and total physical activity time, as well as menopausal status and current use of postmenopausal hormones for women.

Results: Significant, detrimental dose-response associations of television-viewing time were observed with waist circumference, systolic blood pressure, and 2-h plasma glucose in men and women, and with fasting plasma glucose, triglycerides, and HDL-C in women. The associations were stronger in women than in men, with significant gender interactions observed for triglycerides and HDL-C. Though waist circumference attenuated the associations, they remained statistically significant for 2-h plasma glucose in men and women, and for triglycerides and HDL-C in women.

Conclusions: In a population of healthy Australian adults who met the public health guideline for physical activity, television-viewing time was positively associated with a number of metabolic risk variables. These findings support the case for a concurrent sedentary behavior and health guideline for adults, which is in addition to the public health guideline on physical activity.

Prevalence, detection and drug treatment of hypertension in a rural Australian population : the Greater Green Triangle Risk Factor Study 2004

Background: Hypertension is an important risk factor for cardiovascular disease; however, limited findings are available on its detection and management in rural Australia.

Aim: To assess the prevalence, awareness and treatment of hypertension in a rural South-East Australian population.

Methods: Three cross-sectional surveys in Limestone Coast, Corangamite Shire and Wimmera regions during 2004–2006 using a random population sample (n = 3320, participation rate 49%) aged 25–74 years. Blood pressure was measured by trained nurses. Information on history of hypertension and medication was obtained by questionnaires. Hypertension was defined as systolic blood pressure ≥140 mmHg and/or diastolic blood pressure ≥90 mmHg and/or on antihypertensive drug treatment.

Results: Overall, one-third of participants had hypertension; of these, two-thirds, 54% (95% confidence interval (CI) 47–60) of men and 71% (95% CI 65–77) of women, were aware of their condition. Half of the participants with hypertension were treated and nearly half of these were controlled. Both treatment and control were more common in women (60%, 95% CI 54–67 and 55%, 95% CI 47–64) compared with men (42%, 95% CI 36–49 and 35%, 95% CI 26–44). Monotherapy was used by 55% (95% CI 48–61) of treated hypertensives. Angiotensin-converting enzyme inhibitors were the most frequently used class of antihypertensive drugs in men, whereas angiotensin-converting enzyme inhibitors, angiotensin receptor antagonists and diuretics were all widely used among women.

Conclusion: This study emphasizes suboptimal detection and treatment of hypertension, especially in men, in rural Australia.