2016 Consensus statement on prevention of atherosclerotic cardiovascular disease in the Hong Kong population

INTRODUCTION

In Hong Kong, the prevalence of atherosclerotic cardiovascular disease has increased markedly over the past few decades, and further increases are expected. In 2008, the Hong Kong Cardiovascular Task Force released a consensus statement on preventing cardiovascular disease in the Hong Kong population. The present article provides an update on these recommendations.

PARTICIPANTS

A multidisciplinary group of clinicians comprising the Hong Kong Cardiovascular Task Force-10 cardiologists, an endocrinologist, and a family physician-met in September 2014 and June 2015 in Hong Kong.

EVIDENCE

Guidelines from the American College of Cardiology/American Heart Association, the European Society of Hypertension/European Society of Cardiology, and the Eighth Joint National Committee for the Management of High Blood Pressure were reviewed.

CONSENSUS PROCESS

Group members reviewed the 2008 Consensus Statement and relevant international guidelines. At the meetings, each topical recommendation of the 2008 Statement was assessed against the pooled recommendations on that topic from the international guidelines. A final recommendation on each topic was generated by consensus after discussion.

CONCLUSIONS

It is recommended that a formal risk scoring system should be used for risk assessment of all adults aged 40 years or older who have at least one cardiovascular risk factor. Individuals can be classified as having a low, moderate, or high risk of developing atherosclerotic cardiovascular disease, and appropriate interventions selected accordingly. Recommended lifestyle modifications include adopting a healthy eating pattern; maintaining a low body mass index; quitting smoking; and undertaking regular, moderate-intensity physical activity. Pharmacological interventions should be selected as appropriate after lifestyle modification.

Adverse systemic arterial function in patients with selenium deficiency

BACKGROUND

Experimental studies have shown that selenium is involved in the synthesis of selenoproteins which might contribute to cardiovascular protection. However, the relationship between selenium deficiency and vascular function in clinical context remains unknown.

OBJECTIVE

To investigate for any relationship between selenium deficiency and systemic arterial function in patients with high risk of vascular events.

DESIGN

Cross-sectional study.

SETTING AND PARTICIPANTS

306 consecutive patients with high risk for cardiovascular events (coronary artery disease 35%, acute/ recurrent ischemic stroke 40%, diabetes mellitus 54%) followed up at internal medicine outpatient clinics.

MEASUREMENTS

Non-invasive brachial-ankle pulse wave velocity (PWV) was determined using vascular profiling system (VP-2000). Long-term intake of selenium was determined by a validated food frequency questionnaire.

RESULTS

Mean daily selenium intake was 59.5 ± 52.1 mcg/day, and mean PWV was 1782.4 ± 418.4 cm/s. Patients with selenium intake <10th percentile had significantly higher PWV as compared to patients with intake ≥ 10th percentile (1968.2 ± 648.9 cm/s versus 1762.2 ± 381.6 cm/s, P=0.010). After adjusting for potential confounders including age, gender, history of hypertension, hyperlipidemia, diabetes and cardiovascular disease, smoking status, use of cardiovascular medications, waist-hip ratio, education/ financial status, physical activity, calorie intake and intake of antioxidant vitamins, deficient selenium intake <10th percentile remained independently predictive of increased PWV by +363.4 cm/s [95% CI: 68.1 to 658.6, P=0.016, relative increase 21%].

CONCLUSIONS

Selenium deficiency is associated with adverse arterial function in patients with high risk for vascular events.

Cost-effectiveness analysis of applying the Cholesterol and Recurrent Events (CARE) study protocol in Hong Kong

OBJECTIVE

To determine the cost-effectiveness of secondary prevention with pravastatin in Hong Kong patients with coronary heart disease and average cholesterol levels.

DESIGN

Cost-effectiveness analysis based on published results of the CARE study.

PATIENTS

Men and women post-myocardial infarction with average cholesterol levels.

MAIN OUTCOME MEASURES

Cost-effectiveness analysis: cost per life saved, cost per fatal or non-fatal coronary event prevented, cost per procedure prevented, and cost per fatal or non-fatal stroke prevented. Cost-utility analysis: gross cost and net cost per quality-adjusted life year gained calculated using two alternative models.

RESULTS

Cost per life saved or death prevented was HK$4,442,350 (non-discounted); cost per fatal or non-fatal cardiac event prevented HK$1,146,413; cost per procedure prevented HK$732,759; and cost per fatal or non-fatal stroke prevented HK$2,961,566. Net cost per quality adjusted life year gained was HK$73,218 and HK$65,280 non-discounted, respectively using the two alternative models.

CONCLUSIONS

The results of this study can assist in prioritising the use of health care resources in Hong Kong but should be considered alongside the benefits and costs of alternative interventions for coronary heart disease.

Increase in plasma adrenomedullin in patients with heart failure characterised by diastolic dysfunction

OBJECTIVE

To investigate the relation between plasma adrenomedullin and the severity of diastolic dysfunction in patients with heart failure.

DESIGN

Prospective study.

SETTING

University teaching hospital.

PATIENTS

77 patients (mean (SEM) age 66.3 (1.2) years; 75% male) who were being followed in the outpatient clinic after admission to hospital for acute heart failure.

INTERVENTIONS

Same day echocardiography with Doppler studies; determination of venous adrenomedullin concentration by radioimmunoassay.

MAIN OUTCOME MEASURES

Plasma adrenomedullin concentration and its correlation with systolic and diastolic function.

RESULTS

31 patients (40%) had isolated diastolic dysfunction (ejection fraction > 50%), and the remaining 46 had a depressed ejection fraction (< 50%). Of the patients with diastolic dysfunction, 17 had a restrictive filling pattern. In all but one of these there was coexisting systolic failure (chi(2) = 10.7, p = 0.001). Patients with systolic heart failure and a restrictive filling pattern (group 1, n = 16) had a higher plasma adrenomedullin than those with systolic failure and a non-restrictive filling pattern (group 2, n = 30) or with isolated diastolic heart failure and a non-restrictive filling pattern (group 3, n = 30) (mean (SEM): 91.7 (21.1) v 38.4 (8.8) v 34.0 (6.5) pmol/l, both p < 0.05). All heart failure values were higher (p < 0.01) than the control value (6.9 (1.2) pmol/l). Ejection fraction and left ventricular dimensions were similar in groups 1 and 2. Plasma adrenomedullin did not correlate with ejection fraction or New York Heart Association functional class. Stepwise multiple regression analysis showed that the presence of a restrictive filling pattern was the only independent variable associated with a high plasma adrenomedullin.

CONCLUSIONS

Plasma adrenomedullin concentrations in patients with heart failure are determined by the presence of diastolic dysfunction, and are especially raised in the presence of a restrictive filling pattern. There appears to be no correlation with systolic dysfunction.

Comparison of digoxin versus low-dose amiodarone for ventricular rate control in patients with chronic atrial fibrillation

1. Rapid ventricular rate (VR) and rhythm irregularity during atrial fibrillation (AF) impair cardiac performance. Although digoxin has been widely used in patients with AF, its efficacy for the control of VR and rhythm irregularity is unsatisfactory. Whether low-dose amiodarone is more effective remains unclear. 2. We randomized 16 patients (13 male, three female; mean (+/-SD) age 63 +/- 9 years) with chronic AF to receive either digoxin or amiodarone for 24 weeks. At baseline and at 12 and 24 weeks follow up, Holter monitor recording and cardiopulmonary exercise test were performed to assess VR and rhythm irregularity control and exercise capacity. 3. Seven and nine patients received digoxin and amiodarone, respectively. After 12 and 24 weeks treatment, both digoxin and amiodarone significantly decreased the mean ambulatory VR and the VR during peak exercise compared with baseline (all P < 0.05). At 24 weeks, there were no significant differences between digoxin and amiodarone in the percentage reduction in VR during ambulatory (27 +/- 13 vs. 25 +/- 12%, respectively; P = 0.8) and peak exercise (13 +/- 12 vs. 12 +/- 10%%, respectively; P = 0.6). 4. The rhythm irregularity, as measured by SD of RR intervals and the root mean square of the SD of RR intervals, and the exercise capacity, as measured by exercise workload, maximal oxygen consumption (VO2), minute ventilation, ventilatory equivalent and oxygen pulse, were not significantly changed after treatment with digoxin or amiodarone (all P > 0.05). 5. Quality of life, determined by SF-36 questionnaire, and AF symptomatology, as measured by the AF Symptom Checklist, were also not significantly changed after treatment with digoxin or amiodarone (all P > 0.05). 6. In conclusion, digoxin and low-dose amiodarone had similar efficacy in the control of VR during ambulatory activity and exercise. However, both were less efficacious during exercise and did not significantly affect rhythm irregularity, exercise capacity, quality of life and AF symptomatology in patients with chronic AF.

Genetic and clinical features of hemoglobin H disease in Chinese patients

BACKGROUND

Normally, one pair of each of the two alpha-globin genes, alpha1 and alpha2, resides on each copy of chromosome 16. In hemoglobin H disease, three of these four alpha-globin genes are affected by a deletion, a mutation, or both. We studied the alpha1-globin gene abnormalities and the clinical and hematologic features of Chinese patients with hemoglobin H disease in Hong Kong.

METHODS

We assessed the clinical features, hematologic values, serum ferritin levels, and liver function of 114 patients with hemoglobin H disease. We also performed echocardiography and magnetic resonance imaging of the liver and examined the two pairs of alpha-globin genes.

RESULTS

Hemoglobin H disease in 87 of the 114 patients (76 percent) was due to the deletion of three of the four alpha-globin genes (--/-alpha), a combination termed the deletional type of hemoglobin H. The remaining 27 patients (24 percent) had the nondeletional type of hemoglobin H disease, in which two alpha-globin genes are deleted and a third is mutated (--/alphaalphaT). All 87 patients with the deletional type of hemoglobin H were double heterozygotes in whom there was a deletion of both alpha-globin genes from one chromosome, plus a deletion of the alpha1 or alpha2 gene from the other chromosome (--/alpha- or --/-alpha). A variety of mutated alpha-globin genes was found in the patients with nondeletional type of hemoglobin H disease. Patients with the nondeletional type of the H disease had more symptoms at a younger age, more severe hemolytic anemia, and larger spleens and were more likely to require transfusions than patients with deletional hemoglobin H disease. The severity of iron overload was not related to the genotype.

CONCLUSIONS

Chinese patients in Hong Kong with the nondeletional type of hemoglobin H disease have more severe disease than those with the deletional type of the disease. Iron overload is a major cause of disability in both forms of the disease.

Diastolic blood pressure is related to urinary sodium excretion in hypertensive Chinese patients

We studied 70 Hong Kong Chinese patients with untreated hypertension and 47 normotensive controls. Blood pressure measurements and 24-h urine collection were performed for each patient, and were repeated 12 weeks later in 14 hypertensive patients who remained untreated. Twenty-two hypertensive patients underwent ambulatory blood pressure monitoring. The primary hypothesis tested was a correlation between diastolic blood pressure and 24-h urinary sodium excretion. In the hypertensive patients, diastolic blood pressure correlated with 24-h urinary sodium excretion (r=0.41, p<0.001), even after adjustment for age, gender, body mass index, ethanol intake and season (r=0.34, p=0.02). In normotensive controls, diastolic blood pressure did not correlate with sodium excretion (r=0.21, p=0.16). A correlation between diastolic blood pressure and sodium excretion was also observed in the patients who underwent ambulatory blood pressure monitoring (r=0.47, p=0.026), and in repeat measurements in untreated patients (r=0.60, p=0.02). Systolic blood pressure did not correlate with sodium excretion, although it increased with patient age (0.6+/-0.1 mmHg/year, p<0.001). In a multiple regression analysis with diastolic blood pressure as the dependent variable, the regression coefficient was 0.06+/-0.02 mmHg/mmol Na. The regression coefficients for ambulatory diastolic blood pressure and diastolic pressure repeated at 12 weeks were 0.07+/-0.03 and 0. 09+/-0.04 mmHg/mmol Na, respectively. Urinary sodium excretion was related to diastolic blood pressure in our hypertensive patients, accounting for 17% of the variance of diastolic blood pressure.

Clinical predictors of morbidity and mortality in patients with myocardial infarction or revascularization who underwent cardiac rehabilitation, and importance of diabetes mellitus and exercise capacity

This investigation was a prospective, follow-up study to assess whether baseline clinical and investigational parameters were predictors of cardiovascular morbidity and mortality in patients enrolled into the cardiac rehabilitation program. A cohort of 418 patients (70% were men) with coronary heart disease was followed up 3.2 +/- 1.1 years. Two hundred twenty-seven of them (54%) had a recent myocardial infarction (MI), with a thrombolytic rate of 54%. Percutaneous transluminal coronary angioplasty (PTCA) was performed in 45% of patients. The covariates assessed include age, gender, smoking habit, body mass index, the presence of hypertension or diabetes mellitus, exercise habit, site and severity of MI, status of thrombolytic therapy, peak creatine phosphokinase, plasma lipid profiles, ejection fraction, PTCA performed, number of diseased coronary arteries, and exercise capacity. Low-density lipoprotein cholesterol decreased significantly (3.2 +/- 1.0 vs 2.7 +/- 0.7 mmol/L, p < 0.001). The cumulative mortality was 13%. In a univariate model, the parameters that significantly predict mortality included older age, diabetes, low exercise capacity (< or = 4 metabolic equivalents) 3-vessel disease, those without PTCA performed, and a low ejection fraction. In the Cox proportional-hazards model analysis, the independent factors were coexisting diabetes (chi-square 6.1, p = 0.01) and a low metabolic equivalent (chi-square 6.5, p = 0.01). One hundred six patients were rehospitalized for nonfatal cardiovascular events that included unstable angina (48%), heart failure (21%), acute MI (6%), symptomatic arrhythmia (6%), and severe hypertension (1%). Factors that independently predicted rehospitalization were low exercise capacity (p = 0.02) and the presence of diabetes (chi-square 4.8, p = 0.03). Diabetes was also associated with more episodes of hospital admission (2.3 +/- 2.1 vs 1.6 +/- 1.4, p = 0.04) and a longer cumulative hospital stay (25.5 +/- 34.6 vs 11.4 +/- 19.6 days, p = 0.02). Thus, in patients with MI or after PTCA receiving conventional medical therapy, the cardiac rehabilitation program should focus on aggressive diabetic control and enhancement of exercise capacity.

Screening for diseases in elderly persons: the correlation between physical checkup findings and chief complaints

BACKGROUND

The effectiveness of a physical checkup program for screening for diseases in the elderly, in terms of correlation with their chief complaints has not been previously evaluated.

OBJECTIVE AND METHODS

The study was to examine the correlation between physical checkup findings and chief complaints of elderly people. Study subjects were over 65 years of age. There were 792 males and 373 females. They all attended a 2-day physical checkup program at Taichung Veterans General Hospital from January 1, 1994, to December 31, 1995.

RESULTS

The results showed a significant difference (p<0.05) between male (12.0%) and female (16.8%) subjects in the relationship of clinical findings to chief complaints. When the locations of chief complaints were compared, those concerning the neck and the limbs corresponded well to our clinical findings. However, there were differences between female and male subjects (42.4 and 24.4%, respectively; p<0.01) in this aspect. There was a good relationship (p<0.05) between physical checkup findings and complaints of lower back pain (75.2%), upper abdominal pain (46.2%) and knee joint pain (38.3%). However, we found that 43.7% of physical checkup findings were not linked to chief complaints.

CONCLUSIONS

The results suggest that additional appropriate clinical tests may improve the effectiveness of physical checkups and thus result in health benefits for elderly persons.

HpaII polymorphism in the atrial natriuretic peptide gene and hypertension

This was an association study of genetic polymorphisms to compare the distribution of the genotypes and alleles of the HpaII polymorphism of the atrial natriuretic peptide (ANP) gene in hypertensive patients and normotensive controls. The setting was an outpatient clinic run by a University Department handling referrals from primary care. The patient cohort was composed of 217 subjects, consisting of 109 healthy controls and 108 patients with newly diagnosed or documented hypertension. The genomic DNA was extracted from peripheral blood leukocytes, amplified by polymerase chain reaction, and digested with the restriction enzyme HpaII. H1 and H2 alleles were identified after electrophoresis. The main outcome measures were to identify the frequencies of ANP genotypes and alleles in hypertensive patients and normotensive controls. The H1H1, H1H2, and H2H2 genotypes occurred in 1%, 19%, and 80% of controls and 3%, 18%, and 80% of hypertensive patients, respectively. The frequencies of the H1 and H2 alleles were 0.11 and 0.89 in controls and 0.12 and 0.88 in hypertensive patients. The frequencies of the ANP genotypes and alleles did not differ significantly between controls and hypertensive patients. Our findings differed from previous reports and suggested that this polymorphism is not associated with hypertension in this population.

Fosinopril reduces left ventricular mass in untreated hypertensive patients: a controlled trial

AIMS

Left ventricular hypertrophy is a powerful predictor of cardiovascular morbidity and mortality. We tested the hypothesis that fosinopril, an angiotensin-converting enzyme inhibitor, reduces left ventricular mass in hypertensive patients.

METHODS

Thirty-three patients with untreated mild essential hypertension were randomised to treatment with oral fosinopril (10 mg-20 mg daily) or placebo for 12 weeks. The primary outcome measure was the change in left ventricular mass index determined by echocardiography.

RESULTS

Diastolic blood pressure changed from 95.5+/-2.1 mmHg at baseline to 96.6+/-2.8 mmHg at the final visit in control patients and changed from 96.6+/-2.3 mmHg to 91.5+/-3.0 mmHg in patients treated with fosinopril (P= 0.04). Systolic blood pressure changed from 147.4+/-3.2 mmHg at baseline to 152.7+/-4.4 mmHg at the final visit in control patients and changed from 157.6+/-5.1 mmHg to 149.1+/-6.1 mmHg in patients treated with fosinopril (P=0.02). Fosinopril reduced diastolic pressure by 6.3 (95%CI 0.3-12.4) mmHg and systolic pressure by 13.3 (95%CI 2.7-23.8) mmHg compared with placebo. The left ventricular mass index changed from 110.0+/-8.3 gm(-2) to 113.1+/-8.7 g m(-2) in the control patients and changed from 120.8+/-5.8 g m(-2) to 109.0+/-7.5 g m(-2) in patients treated with fosinopril (P=0.02). Fosinopril reduced left ventricular mass index by 14.9 (95%CI 2.2-27.6) g m(-2) compared with placebo. There was no significant change in the left ventricular systolic or diastolic function, nor were there any significant changes in plasma electrolytes and renal function.

CONCLUSIONS

Treatment with fosinopril for 12 weeks reduced left ventricular mass significantly in hypertensive patients.

Decrease with age in frequency of the homozygous deletional angiotensin-converting enzyme genotype in hypertensive patients

1. Angiotensin-converting enzyme (ACE) genotypes in hypertensive patients were studied in order to delineate their cardiovascular risk due to the ACE gene. We hypothesized that the distribution of ACE genotypes may change with age because of the risk of myocardial infarction associated with the homozygous deletional (DD) genotype. 2. A total of 223 subjects were recruited from the Hypertension Outpatient Clinic of the Sai Ying Pun Hospital with consent. They consisted of 75 patients with newly diagnosed or documented hypertension, 46 patients with ischaemic heart disease and 102 normal controls. Genomic DNA was extracted from peripheral leucocytes and amplified by polymerase chain reaction. Insertion (I) or deletion (D) alleles were identified after electrophoresis. The frequencies of ACE genotypes and alleles were measured in three age groups: < 50 years, 50-59 years and > or = 60 years. 3. A significant correlation between ACE genotype and age was found (P = 0.03). The relative frequency of the D allele in those under 50 years of age was similar in controls and hypertensive patients (0.40 vs 0.41; P = 0.94), but was significantly lower in patients > or = 50 years compared with those patients < 50 years of age (0.22 vs 0.41; P = 0.01). 4. The observed decrease in frequency of the DD genotype in older hypertensive patients is consistent with the increase in cardiovascular risk associated with the D allele and raises the possibility that the DD genotype may increase the risk of premature death, at least in the population studied.

Amlodipine, felodipine, and isradipine in the treatment of Chinese patients with mild-to-moderate hypertension

Optimal treatment of hypertension requires the use of effective antihypertensive drugs. Calcium channel blockers are widely used in the treatment of hypertension and appear to be particularly efficacious in ethnic Chinese patients. The aim of this open-label study was to prospectively investigate the efficacy and tolerability of three dihydropyridine calcium channel blockers in sequence, using the same protocol for each. After 2 weeks of placebo treatment, 73 males and 45 females (mean age, 45 +/- 10 years; mean weight, 67 +/- 10 kg) with essential hypertension (diastolic blood pressure, 95 to 115 mm Hg) were treated with amlodipine (n = 41), felodipine (n = 38), or isradipine (n = 39) for 8 weeks, with dose titration after 4 weeks. Mean seated systolic and diastolic blood pressure decreased by 23/17, 30/17, and 20/15 mm Hg after 8 weeks of treatment with amlodipine, felodipine, and isradipine, respectively. These reductions were all statistically significant. Blood pressure was controlled (defined as diastolic pressure < 90 mm Hg at the final visit or a decrease from baseline of > or = 10 mm Hg) in 85%, 74%, and 74% of patients receiving amlodipine, felodipine, and isradipine, respectively. There were no significant changes in heart rate, plasma lipid levels, or serum biochemistry markers with any of the three treatments. No serious adverse events occurred, but mild adverse effects, including headaches, flushing, tachycardia, dizziness, and edema, were reported; 1 (2%), 6 (16%), and 5 (13%) patients receiving amlodipine, felodipine, and isradipine, respectively, withdrew from the study (P < 0.05). The results of this study indicate that all three drugs are highly effective in lowering blood pressure and are well tolerated in Chinese patients with mild-to-moderate hypertension.

M235T polymorphism of the angiotensinogen gene and hypertension in Chinese

OBJECTIVES

To compare the distributions of the genotypes and alleles of the M235T polymorphism of the angiotensinogen gene for hypertensive patients and normotensive controls.

DESIGN

A study of association of genetic polymorphisms.

SETTING

An outpatient clinic run by a university department handling referrals from primary care.

PATIENTS

Two hundred and four subjects, 103 normal controls and 101 patients with newly diagnosed or documented hypertension.

METHOD

Genomic DNA was extracted from peripheral blood leucocytes, amplified by polymerase chain reaction and digested with the restriction enzyme Tth 111 I. Methionine (M) and threonine (T) alleles were identified after electrophoresis.

MAIN OUTCOME MEASURES

Prevalences of angiotensinogen genotypes and alleles for hypertensive patients and controls.

RESULTS

MM, TM and TT genotypes occurred in 3, 24 and 73% of controls and 1, 22 and 77% of hypertensive patients, respectively. The prevalences of the M and T alleles were 0.15 and 0.85 among controls and 0.12 and 0.88 among hypertensive patients. The prevalences of the angiotensinogen genotypes and alleles for controls and hypertensive patients did not differ significantly.

CONCLUSIONS

Our findings differed from previous reports and suggested that this polymorphism is not associated with hypertension in this population.

Plasma concentration of brain natriuretic peptide is related to diastolic function in hypertension

1. The plasma brain natriuretic peptide (BNP) concentration is elevated in patients with essential hypertension and normal systolic function. This may be related to left ventricular hypertrophy or diastolic dysfunction, both of which commonly occur in hypertension. 2. Echocardiography was performed on 32 patients with newly diagnosed untreated mild-to-moderate hypertension (19 men, 13 women; mean +/- SD age 51 +/- 15 years; diastolic blood pressure 99 +/- 12 mmHg; systolic blood pressure 153.2 +/- 18.0 mmHg; plasma creatinine 86 +/- 15 mumol/L; creatinine clearance 92.2 +/- 20.5 mL/min; left ventricular mass index 116 +/- 28 g/m2; left ventricular ejection fraction 66 +/- 9%). A 15 mL peripheral venous blood sample was obtained at the time of echocardiography for radioimmunoassay of BNP. 3. Sixteen patients had abnormal Doppler transmittal flow (E/A ratio < 1) and a higher median plasma BNP concentration compared with those patients with E/A > or = 1 (12.9 vs 5.9 pmol/L, respectively; P = 0.006). The plasma BNP level correlated significantly with E/A ratio (r = -0.50; P = 0.035). Multivariate analysis showed that the E/A ratio is related to plasma BNP, independent of age and blood pressure. 4. Our results suggest that the plasma BNP level is influenced by diastolic dysfunction. Further studies are needed to determine whether assay of plasma BNP helps to identify patients with diastolic dysfunction.

Relative efficacy and tolerability of lacidipine and amlodipine in patients with mild-to-moderate hypertension: a randomized double-blind study

Calcium channel blockers are increasingly used in the treatment of hypertension. Newer calcium channel blockers of the dihydropyridine group have longer elimination half-lives (t1/2) that permit once-daily dosage and are generally better tolerated than their parent compound. In this study, the efficacy and safety of lacidipine and amlodipine were compared in 65 patients with mild-to-moderate hypertension attending the hypertension outpatient clinic of a teaching hospital in a randomized double-blind cross-over trial with dose titration. Lacidipine and amlodipine both significantly reduced systolic blood pressure (SBP: by 19.2 +/- 13.5 and 22.3 +/- 15.3 mm Hg, respectively) and diastolic BP (DBP: 13.3 +/- 4.2 and 12.3 +/- 5.3 mm Hg, respectively) 24 h postdose. There were no significant differences in their antihypertensive effects. The incidence of adverse events (AE) was 3% for lacidipine and 8% for amlodipine. The incidence of withdrawal from the study due to side effects was 0% for lacidipine and 3% for amlodipine. These results suggest that lacidipine is well-tolerated, and is as effective as amlodipine as a once-daily antihypertensive agent.

Collagen induces cytokine production by synovial fluid mononuclear cells in rheumatoid arthritis

Synovial fluid (SF) mononuclear cells (MNC) from 13 patients with rheumatoid arthritis (RA) and 12 patients with other arthritic diseases (OD) including osteoarthritis (OA), gout and spondyloarthritis (SA) were cultured in the presence of collagen types I and II or lipopolysaccharide (LPS) for 24 h. Interleukin-1 (IL-1), IL-6 and tumor necrosis factor-alpha (TNF-alpha) in the SF and culture supernatants were assayed using ELISA. The results showed that one-half of the RA patients with high SF monocyte count had high SF IL-6 levels that coincided with the high spontaneous release of IL-6 by SF MNC. In the other RA patients with lower SF monocyte count, type II collagen induced significantly higher IL-1 beta than the medium control levels by SF MNC (P < 0.01) or that of the other diseases (P < 0.01). Similarly, type II collagen-induced IL-6 and TNF-alpha production rose significantly (P < 0.01) from SF MNC of RA but less from OD (P < 0.05). In addition, type I collagen could also induce IL-1, IL-6 and TNF-alpha in these samples from RA and OD patients but was less potent than type II collagen. Our results indicate that collagen-induced cytokines may be important in the pathogenesis of the disease.

Effects of physiological increments in human alpha-atrial natriuretic peptide and human brain natriuretic peptide in normal male subjects

1. Brain natriuretic peptide, closely related to atrial natriuretic peptide in structure, may be an important circulating hormone. Its physiological role is unclear. First, we studied the effects of incremental infusions of brain natriuretic peptide in six healthy men on plasma brain natriuretic peptide levels and the pharmacokinetics of brain natriuretic peptide. Synthetic human brain natriuretic peptide-32 was infused intravenously, at an initial rate of 0.4 pmol min-1 kg-1, doubling every 15 min until the dose rate reached 6.4 pmol min-1 kg-1, at which rate the infusion was maintained for 30 min. 2. The brain natriuretic peptide infusion raised the brain natriuretic peptide-like immunoreactivity from 1.4 +/- 0.5 pmol/l to 21.4 +/- 7.6 pmol/l. Brain natriuretic peptide-like immunoreactivity after the end of infusion was consistent with a bi-exponential decay, with half-lives of 2.1 min and 37 min. 3. Next, we studied the effects of low-dose infusion of brain natriuretic peptide to mimic physiological increments in the circulating levels in comparison with atrial natriuretic peptide. Six dehydrated male subjects received intravenous infusions of atrial natriuretic peptide and brain natriuretic peptide, separately and in combination, in a randomized double-blind, placebo-controlled, four-part cross-over design. Atrial natriuretic peptide and brain natriuretic peptide were given at the rate of 0.75 and 0.4 pmol min-1 kg-1, respectively, for 3 h. The control infusion consisted of the vehicle. 4. Analysis of variance showed that atrial natriuretic peptide and atrial natriuretic peptide plus brain natriuretic peptide, but not brain natriuretic peptide alone, increased urinary flow and decreased urinary osmolality significantly.(ABSTRACT TRUNCATED AT 250 WORDS)

Plasma brain natriuretic peptide and C-type natriuretic peptide in essential hypertension

OBJECTIVES

To study the relationship between hypertension and the plasma levels of brain natriuretic peptide (BNP) and C-type natriuretic peptide (CNP), and to determine whether the plasma levels of BNP and CNP are correlated.

DESIGN

A cross-sectional study of the plasma levels of BNP and CNP in hypertensive patients and normotensive controls matched for age and sex was performed.

SETTING

The hypertension research clinic in a teaching hospital and well-person risk factor screening clinics in general practice health centres.

PARTICIPANTS

Fifty-four subjects (29 hypertensive, 25 normotensive controls) took part in the study after giving their informed consent. Hypertensive patients (n = 19) were paired with normotensive controls (n = 19) matched for age and sex to form a subgroup before analysis of the plasma.

METHODS

The plasma levels of BNP and CNP were determined by specific radioimmunoassays.

RESULTS

The mean plasma concentration of BNP was significantly higher in the hypertensive group than in the paired controls. In contrast, the mean plasma concentration of CNP was not significantly different in the hypertensive group than in the paired controls. Multiple regression analysis of all 54 subjects showed that the plasma level of BNP correlated significantly with age and systolic blood pressure, whereas the plasma level of CNP correlated significantly with sex, heart rate and alcohol intake. The CNP levels did not correlate significantly with either systolic or diastolic blood pressure, or with plasma brain natriuretic levels.

CONCLUSIONS

Hypertension is associated with raised BNP but not CNP plasma levels.