BACKGROUND:Cardiovascular risk-prediction models are used in clinical practice to identify and treat high-risk populations, and to communicate risk effectively. We assessed the validity and utility of four cardiovascular risk-prediction models in an Asian population of a middle-income country.
METHODS:Data from a national population-based survey of 14,863 participants aged 40 to 65 years, with a follow-up duration of 73,277 person-years was used. The Framingham Risk Score (FRS), SCORE (Systematic COronary Risk Evaluation)-high and -low cardiovascular-risk regions and the World Health Organization/International Society of Hypertension (WHO/ISH) models were assessed. The outcome of interest was 5-year cardiovascular mortality. Discrimination was assessed for all models and calibration for the SCORE models.
RESULTS:Cardiovascular risk factors were highly prevalent; smoking 20%, obesity 32%, hypertension 55%, diabetes mellitus 18% and hypercholesterolemia 34%. The FRS and SCORE models showed good agreement in risk stratification. The FRS, SCORE-high and -low models showed good discrimination for cardiovascular mortality, areas under the ROC curve (AUC) were 0.768, 0.774 and 0.775 respectively. The WHO/ISH model showed poor discrimination, AUC=0.613. Calibration of the SCORE-high model was graphically and statistically acceptable for men (χ(2) goodness-of-fit, p=0.097). The SCORE-low model was statistically acceptable for men (χ(2) goodness-of-fit, p=0.067). Both SCORE-models underestimated risk in women (p<0.001).
CONCLUSIONS:The FRS and SCORE-high models, but not the WHO/ISH model can be used to identify high cardiovascular risk in the Malaysian population. The SCORE-high model predicts risk accurately in men but underestimated it in women.
KEYWORDS:Cardiovascular disease prevention; Mortality; Risk prediction; Risk score; Validation
Irregular atrial pressure, defective folate and cholesterol metabolism contribute to the pathogenesis of hypertension. However, little is known about the combined roles of the methylenetetrahydrofolate reductase (MTHFR), apolipoprotein-E (ApoE) and angiotensin-converting enzyme (ACE) genes, which are involved in metabolism and homeostasis. The objective of this study is to investigate the association of the MTHFR 677 C>T and 1298A>C, ACE insertion-deletion (I/D) and ApoE genetic polymorphisms with hypertension and to further explore the epistasis interactions that are involved in these mechanisms. A total of 594 subjects, including 348 normotensive and 246 hypertensive ischemic stroke subjects were recruited. The MTHFR 677 C>T and 1298A>C, ACE I/D and ApoEpolymorphisms were genotyped and the epistasis interaction were analyzed. The MTHFR 677 C>T and ApoE polymorphisms demonstrated significant associations with susceptibility to hypertension in multiple logistic regression models, multifactor dimensionality reduction and a classification and regression tree. In addition, the logistic regression model demonstrated that significant interactions between the ApoE E3E3, E2E4, E2E2 and MTHFR 677 C>T polymorphisms existed. In conclusion, the results of this epistasis study indicated significant association between the ApoE and MTHFR polymorphisms and hypertension.
Pulmonary hypertension is frequently associated with atrial septal defect and various connective tissue disorders. This case describes a 74-year-old woman who presented with symptoms of heart failure and concomitant involvement of salivary glands and keratoconjunctivitis. An echocardiogram demonstrated ostium secundum atrial septal defect with left to right shunt and severe pulmonary hypertension. Laboratory investigations confirmed the diagnosis of Sjögren's syndrome (SS) with positive anti-nuclear factor and centromere SS-A/Ro pattern. Anti-Ro (SS-A) was found positive. Atrial septal defect was closed through transcatheter route with significant improvement in clinical outcome. This case report suggests a possible association of atrial septal defect with primary Sjögren's syndrome in an adult patient.
There are increasing researches about non-communicable disease such as elevated blood pressure among people living with HIV before and after initiation of highly active antiretroviral therapy (HAART). This cross-sectional study was designed to determine the prevalence of hypertension and associated risk factors among 340 HIV-infected patients on antiretroviral therapy at a Malaysian public hospital providing HIV-related treatment. Data on socioeconomic background, anthropometry, medical history and dietary intake of the patients were collected. Hypertension is defined as blood pressure >=130/85 (mm Hg). Prevalence of hypertension was 45.60% (n=155) of which 86.5% of the hypertensive group were male (n=134). The results showed that increase in age (OR 1.051, 95% confidence interval (CI) 1.024-1.078), higher body mass index (OR 1.18, 95%CI 1.106-2.71), bigger waist circumference (OR 1.18, 95%CI 1.106-2.71), higher waist-hip ratio (OR 1.070, 95%CI 1.034-1.106), higher fasting plasma glucose (OR 1.332, 95%CI 0.845-2.100) and percentage energy intake from protein >15 (OR 2.519, 95%CI 1.391-4.561) were significant risk factors for hypertension (p<0.001). After adjusting for other variables, increasing age (adjusted odds ratio (aOR) 1.069 95%CI 1.016-1.124, p=0.010), being male (aOR 3.026, 95%CI 1.175-7.794, p=0.022) and higher body mass index (aOR 1.26, 95%CI 1.032-1.551, p=0.024) were independently associated with hypertension. None of the antiretroviral therapy and immunologic factors was linked to hypertension. In conclusion hypertension among PLHIV was linked to the well-known risk factors such as age, gender and body mass index. With HAART, people can live longer by making monitoring and control of some reversible factors, especially excessive weight gain for maintaining quality of life.
The sympathetic nervous system plays a major role in blood pressure regulation. Beta 2 (β2) adrenoceptor gene polymorphisms have been associated with hypertension in different populations with conflicting results. We examined the association of three common polymorphisms, Arg16Gly, Gln27Glu, and Thr164Ile, of the β2 adrenoceptor gene in Malaysian hypertensive subjects. A total of 160 hypertensive and control subjects were recruited. Systolic blood pressure (SBP), diastolic blood pressure (DBP), and anthropometric measurements were obtained from each subject. Biochemical analyses of lipid profiles were conducted with an autoanalyzer. DNA samples were extracted from blood and buccal cells. Genotyping was accomplished with polymerase chain reaction-restriction fragment length polymorphism. SBP, DBP, body mass index, and biochemical factors all differed significantly between case and control subjects (P < 0.05). The genotype frequencies of Arg16Arg, Arg16Gly, and Gly16Gly were 22.5, 70, and 7.5% among cases and 33.1, 63.1, and 3.8% among controls, respectively. The genotype frequencies of Gln27Gln, Gln27Glu, and Glu27Glu among cases were 41.1, 50, and 1.9% compared to 77.5, 20.6, and 1.9% among controls, respectively. In this study, the Gln27Glu polymorphism was significantly associated with Malaysian hypertensive subjects (P < 0.05). Therefore, the Gln27Glu polymorphism of the β2 adrenoceptor could be a risk factor associated with hypertension among Malaysians.
PURPOSE: This study aimed to understand hypertensive patients' perceptions of and adherence to prescribed medication.
METHODS: A qualitative research study based on 23 purposely selected participants from a community health clinic in Malaysia. The participants underwent in-depth semi-structured interviews, and the data were analyzed using qualitative content analysis method.
RESULTS: The participants were presented with six types of perceptions of medication. The majority of the participants had negative perceptions of Western medicine (WM), self-adjusted their prescribed medication with complementary and alternative medicine (CAM) and concealed their self-adjusting habits from their doctors. Participants who thought positively of WM took their prescribed medication regularly. Most of the participants perceived the nature of WM as not being curative because of its side effects. Patients have the right to choose their preferred medication when they understand their illness.
CONCLUSION: Local health care systems should provide patients with alternative health services that suit their requests.
KEYWORDS: Adherence; Complementary and alternative medicine; Hypertension; Qualitative research
Study site: Klinik kesihatan, Selangor, Malaysia
The coexistence of hypertension and diabetes results in the rapid development of nephropathy. Hydrogen sulfide (H2S) is claimed to control the vascular and renal functions. This study tested the hypothesis that exogenous H2S lowers the blood pressure and decreases the progression of nephropathy in spontaneously hypertensive rats (SHR) that were diabetic. Eighteen SHR were divided into three groups: SHR, SHR diabetic, and SHR diabetic treated with a group of Wistar-Kyoto rats serving as normotensive nondiabetic control. Diabetes was induced with streptozotocin (STZ) in two groups and one diabetic group received sodium hydrosulfide (NaHS), a H2S donor for 5 weeks. Blood pressure was measured in conscious and anesthetized states and renal cortical blood perfusion in acute studies. Plasma and urinary H2S levels, creatinine concentrations, and electrolytes were measured on three different occasions throughout the 35-day period. Diabetic SHR had higher blood pressure, lower plasma and urinary H2S levels, and renal dysfunction as evidenced by increased plasma creatinine, creatinine clearance, and decreased urinary sodium-to-potassium ratio and renal cortical blood perfusion. NaHS reduced blood pressure, increased H2S levels in plasma and urinary excretion, and reversed the STZ-induced renal dysfunction. The findings of this study suggest that the administration of exogenous H2S lowers the blood pressure and confers protection against the progression of STZ-induced nephropathy in SHR.
Study design: A cross-sectional study was conducted in all states of Malaysia to determine the prevalence, awareness, treatment and control of hypertension. A stratified two-stage cluster sampling design with proportional allocation was used.
Methods: Trained nurses obtained two blood pressure measurements from each subject. Hypertension was defined as mean systolic blood pressure >140 mmHg, diastolic blood pressure >90 mmHg, or a self-reported diagnosis of hypertension and taking antihypertensive medication. All data were analysed using Stata 9.2 software and took the complex survey design into account. A two-sided P-value of <0.05 was considered to be statistically significant.
Results: The overall prevalence of hypertension for subjects aged 15 years was 27.8% (95% confidence interval (CI) 26.9-28.8). The prevalence of hypertension was significantly higher in males (29.6%, 95% CI 28.3-31.0) compared with females (26.0%, 95% CI 25.0-27.1). Multivariate logistic regression showed that the odds of having hypertension increased with increasing age, in males, in subjects with a family history of hypertension, with increasing body mass index, in non-smokers and with decreasing levels of education. Only 34.6% of the subjects with hypertension were aware of their hypertensive status, and 32.4 were taking antihypertensive medication. Amongst the latter group, only 26.8% had their blood pressure under control. The prevalence of hypertension amongst those aged 30 years has increased from 32.9% in 1996 to 40.5% in 2004.
Conclusion: In Malaysia, the prevalence of hypertension is high, but levels of awareness, treatment and control are low. There is an urgent need for a comprehensive integrated population-based intervention programme to ameliorate the growing problem of hypertension in Malaysians.
Two hundred and seventeen diabetic patients attending the eye clinic were examined to determine the prevalence of retinal changes, and the association between diabetic retinopathy and risk factors. A detailed fundus examination was done, after dilating the pupils, using 90 D lens and slitlamp biomicroscope. Diabetic retinopathy was detected in 112 patients (51.6%). Background retinopathy was seen in 40 out of 217 (18.4%), pre-proliferative retinopathy in 11 (5.1%), proliferative retinopathy in 61 (28.1%) and maculopathy in 58 (26.7%) patients. Factors significantly associated with occurrence of retinopathy were duration of diabetes, presence of hypertension and presence of systemic complications (diabetic foot ulcer, lower limb amputation, nephropathy, and peripheral neuropathy).
Study site: Eye clinic, University Malaya Medical Centre (UMMC), Kuala Lumpur, Malaysia
The use and reasons for use of Complementary Medicine (CM) amongst hypertensive patients attending the Hypertension/ Diabetes/ Asthma Clinic in Greentown Health Clinic, Ipoh was assessed. One hundred and twenty patients were selected by systematic random sampling (1:5) over a 2-week period commencing 26/04/04. Data was obtained from interviews, questionnaires and medical records. Twenty seven percent were on CM. Most commonly used CM was herbal medicine. Majority of those using CM for BP control were Malays. The Chinese and Indians were using CM mainly for other health problems. Ninety six percent were using both CM and conventional therapy concurrently. Therefore doctors should enquire about CM usage during patient assessment to prevent possible drug interactions.
The hypertensive patient with type 2 diabetes is especially at risk of adverse cardiovascular events. The United Kingdom Prospective Diabetes Study (UKPDS) and Hypertension Optimal Treatment (HOT) studies suggested that treatment to a lower target blood pressure resulted in better prevention of clinical disease in these patients. Most trials comparing antihypertensive drugs have shown only minimal differences between the various agents. The evidence from the trials suggests that diuretics, beta-blockers, calcium channel blockers (CCBs), angiotensin-converting enzyme (ACE) inhibitors, and the angiotensin-receptor antagonists (ARBs) will all successfully reduce adverse clinical events. The largest of the comparative hypertensive drug trials, the Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial (ALLHAT), demonstrated that a diuretic has a better hypotensive effect, and was more successful in preventing many aspects of cardiovascular disease compared with CCBs and ACE inhibitors. The importance of good blood pressure control and the general equivalence of antihypertensive drugs were again shown in the Valsartan Antihypertensive Long-term Use Evaluation (VALUE) trial, which compared an ARB with a CCB. Choice of antihypertensive agent should be individualized and guided by the presence of concomitant clinical disease and the need to protect any specific target organ system in the diabetic hypertensive. Diuretics, being potent hypotensive drugs with clearly demonstrated clinical benefit, should form part of the antihypertensive regimen of most diabetic hypertensives. ACE inhibitors and ARBs are especially useful in preventing nephropathy. Most patients will require a combination of antihypertensive drugs to achieve tight blood pressure control of under 130/80 mm Hg in the diabetic hypertensive. The clinician should concentrate on seeking this lower target blood pressure rather than be excessively concerned about which is the best antihypertensive agent.
Human Immunodeficiency Virus (HIV)-related pulmonary hypertension is a relatively rare disease that can affect HIV sufferers. This is almost always associated with a poor outcome and death. An 18 month-old girl, probably the youngest on record, was diagnosed to have pulmonary hypertension (PHT) and retrospectively found to have HIV infection. Sildenafil was used to control her PHT and she remains alive even after 2 years.
In view of the high anti-oxidative potential oftocotrienol, the role of the tocotrienol-rich fraction (TRF) of palm oil in preventing pregnancy induced hypertension (PIH) was explored in a randomized double-blind placebo-controlled clinical trial in an urban teaching hospital. Healthy primigravidae were randomized to receive either oral TRF 100 mg daily or placebo, from early second trimester until delivery. Out of 299 women, 151 were randomized into the TRF arm and 148 into the placebo arm. A total of 15 (5.0%) developed PIH. Although there was no statistically significant difference in the incidence of PIH (4/151 or 2.6% in the TRF arm vs. 11/148 or 7.4% in the placebo arm, p = 0.058) between the two arms, there was a tendency towards a lower incidence of PIH in the TRF arm compared to the placebo arm. With TRF supplementation, the relative risk (RR) of PIH was 0.36 (95% CI 0.12-1.09). In conclusion, although TRF from palm oil does not statistically significantly reduce the risk of development of PIH in the population studied, the 64% reduction in incidence of PIH is substantial. The findings warrant further clinical trials, particularly in high risk populations.
The study was conducted to determine whether the clinical targets for the control of diabetes recommended by American Diabetes Association can be met in the context of routine diabetes practice. This cross-sectional study was undertaken on 211 type 2 diabetic patients at the Outpatients Diabetes Clinic, Hospital Universisti Sains Malaysia (HUSM) Kubang Kerian, Kelantan between the year 2001-2002. Patients' physical examination and their medical history as well as their family history were obtained by administering a structured questionnaire. Samples of patients' venous blood during fasting were taken and analysed for plasma glucose, glycated haemoglobin and lipid profile. Analysis showed that many patients had comorbidities or complications. A large number of them had poor glycaemic control (73%). Systolic and diastolic blood pressures of 75% and 85% subjects were > or = 130 and > or = 80 mmHg, respectively. Body Mass Index (BMI) values of 66% of the patients were outside the clinical target (BMI > or = 25 in male and > or = 24 kg/m2 in female). The lipid profile showed that 96% of the patients had at least one lipid value outside the clinical target level. In this study, 70% of the patients had total cholesterol > or = 5.2 mmol/L, 87% had LDL cholesterol > or = 2.6 mmol/L, 57% had HDL cholesterol less than the normal range, < or = 1.15 mmol/L in men and < or = 1.4 mmol/L in women, while 46% had triglycerides > or = 1.71 mmol/L. Complications of diabetes were observed in 48% of the total number of patients. As for the patients' systolic blood pressure, age and duration of diabetes were found to have significant effects. Older subjects with a longer duration of diabetes were more hypertensive. Variables that had significant effects on BMI were age, duration of diabetes, glycaemic control and gender. Younger females and newly diagnosed subjects with better glycaemic control (A1C < 7%) were found to have higher BMI values. The overall clinical targets were suboptimal. The prevalence of hyperlipidaemia and hypertension was high. It is imperative that better treatment strategies and methods be adopted to enhance diabetes control and reduce long-term complications of the disease.
Study site: Outpatients Diabetes Clinic, Hospital Universisti Sains Malaysia (HUSM)
This cross-sectional study was aimed to identify the predictors of medication noncompliance in hypertensive patients. The study was conducted at the Family Medicine Clinic, Hospital Universiti Sains Malaysia, Kelantan, Malaysia, which is a university-based teaching hospital. All hypertensive patients aged 40 or over-registered from January to June 2004, who had been on treatment for at least 3 months, were screened. Previously validated self-administered questionnaires were used to assess the compliance and psychosocial factors. A total of 240 hypertensive patients were recruited in the study. Of these, 55.8% were noncompliant to medication. Logistic regression showed that age (adjusted odds ratio (OR): 0.96; 95% confidence interval (CI): 0.92-0.997; P: 0.035), patient satisfaction (adjusted OR: 0.97; 95% CI: 0.93-0.998; P: 0.036) and medication barrier (adjusted OR: 0.95; 95% CI: 0.91-0.987; P: 0.009) were significant predictors of medication noncompliance. Therefore, younger age, poor patient satisfaction and medication barrier were identified as independent psychosocial predictors of medication noncompliant in hypertensive patients.
Essential hypertension is a major public health concern worldwide where its prevalence accounts for various cerebrovascular diseases. A common molecular variant of angiotensinogen (AGT), the precursor of potent vasoactive hormone angiotensin II, has been incriminated as a marker for genetic predisposition to essential hypertension in some ethnics. This case-control study was designed not only to determine the association of the AGT M235T gene variants with essential hypertension, but also its relationship to Plasma Renin Activity (PRA) in subjects attending the Health Clinic, Kuala Lumpur, Malaysia.
Hypertension is prevalent in 75-80% of hemodialysis patients and remains the most controversial prognostic marker in end stage kidney disease patients. In contrast to the general population where systolic blood pressure of ≤120 mm Hg is considered normal, a debate remains regarding the ideal target blood pressure in hemodialysis patients. Using the PUBMED and EMBASE databases, the research studies that evaluated the relationship between blood pressure measurements and mortality in hemodialysis patients were searched. Thirteen studies were identified from different regions of the world. Five studies reported low predialysis systolic blood pressure as a prognostic marker of mortality. Other studies showed varying results and reported postdialysis systolic blood pressure as well as ambulatory blood pressure as better predictors of mortality and emphasized their optimized control. One study in this review concluded that there is no direct relationship between mortality and blood pressure if the patients are on anti-hypertensive medications. The observed all-cause mortality varied from 12% to 36%, whereas the cardiovascular mortality varied from 16% to 60%. On the basis of studies included in the current review, a low predialysis systolic blood pressure (<120 mm Hg) is shown to be a widely accepted prognostic marker of mortality while ambulatory blood pressure best predicts CV mortality. Therefore, we recommend that apart from routine BP (pre, post and intradialysis) monitoring in centers, assessment of ambulatory BP must be mandatory for all patients to reduce CV mortality in hemodialysis patients.
Antioxidant protection provided by different doses of alpha-tocopherol was compared by determining nitric oxide synthase (NOS) activity in blood vessels of spontaneously hypertensive rats (SHR) treated with alpha-tocopherol. SHR were divided into four groups namely hypertensive control (C), treatment with 17 mg of alpha-tocopherol/kg diet (alpha1), 34 mg of alpha-tocopherol/kg diet (alpha2), and 170 mg of alpha-tocopherol/kg diet (alpha3). Wister Kyoto (WKY) rats were used as normal control (N). Blood pressure were recorded from the tail by physiography every other night for the duration of the study period of 3 months. At the end of the trial, animals were sacrificed. The NOS activity in blood vessels was measured by [3H]arginine radioactive assay and the nitrite concentration in plasma by spectrophotometry at wavelength 554 nm using Greiss reagent. Analysis of data was done using Student's t test and Pearson's correlation. The computer program Statistica was used for all analysis. Results of our study showed that for all the three alpha-tocopherol-treated groups, blood pressure was significantly (P < .001) reduced compared to the hypertensive control and maximum reduction of blood pressure was shown by the dosage of 34 mg of alpha-tocopherol/kg diet (C: 209.56 +/- 8.47 mm Hg; alpha2: 128.83 +/- 17.13 mm Hg). Also, NOS activity in blood vessels of SHR was significantly lower than WKY rats (N: 1.54 +/- 0.26 pmol/mg protein, C: 0.87 +/- 0.23 pmol/mg protein; P < .001). Although alpha-tocopherol in doses of alpha1, alpha2, and alpha3 increased the NOS activity in blood vessels, after treatment only that of alpha2 showed a statistical significance (P < .01). Plasma nitrite concentration was significantly reduced in SHR compared to normal WKY rats (N: 54.62 +/- 2.96 mol/mL, C: 26.24 +/- 2.14 mol/mL; P < .001) and accordingly all three groups showed significant improvement in their respective nitrite level (P < .001). For all groups, NOS activity and nitrite level showed negative correlation with blood pressure. It was significant for NOS activity in hypertensive control (r = -0.735, P = .038), alpha1 (r = -0.833, P = .001), and alpha2 (r = -0.899, P = .000) groups. For plasma nitrite, significant correlation was observed only in group alpha1 (r = -0.673, P = .016) and alpha2 (r = -0.643, P = .024). Only the alpha2 group showed significant positive correlation (r = 0.777, P = .003) between NOS activity and nitrite level. In conclusion it was found that compared to WKY rats, SHR have lower NOS activity in blood vessels, which upon treatment with antioxidant alpha-tocopherol increased the NOS activity and concomitantly reduced the blood pressure. There was correlation of lipid peroxide in blood vessels with NOS and nitric oxide, which implies that free radicals may be involved in the pathogenesis of hypertension.
We describe what we believe is the first reported case of a sublingual hematoma secondary to severe hypertension. The patient, a 77-year-old woman, experienced a spontaneous hematoma of the floor of the mouth, tongue, and sublingual space that eventually caused an airway obstruction. We performed an emergency tracheostomy under local anesthesia and then evacuated the hematoma through an incision along the floor of the mouth. The patient recovered uneventfully.
We determine the prevalence and determinants of clustering of hypertension, abnormal glucose tolerance, hypercholesterolaemia and overweight in Malaysia. A national probability sample of 17,392 individuals aged 30 years or older had usable data. 61% of adults had at least one risk factor, 27% had 2 or more risk factors. The observed frequency of 4 factors cluster was 6 times greater than that expected by chance. Indian and Malay women were at particular high risk of risk factors clustering. Individuals with a risk factor had 1.5 to 3 times higher prevalence of other risk factors. Ordinal regression analyses show that higher income, urban residence and physical inactivity were independently associated with risk factors clustering, lending support to the hypotheses that risk factors clustering is related to lifestyle changes brought about by modernisation and urbanisation. In conclusion, risk factor clustering is highly prevalent among Malaysian adults. Treatment and prevention programme must emphasise the multiple risk factor approach.
Study name: National Health and Morbidity Survey (NHMS-1996)