Kwok Leung Ong

Prevalence, Awareness, Treatment, and Control of Hypertension Among United States Adults 1999–2004

Detection of hypertension and blood pressure control are critically important for reducing the risk of heart attacks and strokes. We analyzed the trends in the prevalence, awareness, treatment, and control of hypertension in the United States in the period 1999–2004. We used the National Health and Nutrition Examination Survey 1999–2004 database. Blood pressure information on 14 653 individuals (4749 in 1999–2000, 5032 in 2001–2002, and 4872 in 2003–2004) aged ≥18 years was used. Hypertension was defined as blood pressure ≥140/90 mm Hg or taking antihypertensive medications. The prevalence of hypertension in 2003–2004 was 7.3±0.9%, 32.6±2.0%, and 66.3±1.8% in the 18 to 39, 40 to 59, and ≥60 age groups, respectively. The overall prevalence was 29.3%. When compared with 1999–2000, there were nonsignificant increases in the overall prevalence, awareness, and treatment rates of hypertension. The blood pressure control rate was 29.2±2.3% in 1999–2000 and 36.8±2.3% in 2003–2004. The age-adjusted increase in control rate was 8.1% (95% CI: 2.4 to 13.8%; P=0.006). The control rates increased significantly in both sexes, non-Hispanic blacks, and Mexican Americans. Among the ≥60 age group, the awareness, treatment, and control rates of hypertension had all increased significantly (P≤0.01). The improvement in blood pressure control is encouraging, although the prevalence of hypertension has not declined.

Diabetes Prevalence and Therapeutic Target Achievement in the United States, 1999 to 2006

OBJECTIVE Changes in the prevalence, treatment, and management of diabetes in the United States from 1999 to 2006 were studied using data from the National Health and Nutrition Examination Survey. METHODS Data on 17,306 participants aged 20 years or more were analyzed. Glycemic, blood pressure, and cholesterol targets were glycosylated hemoglobin less than 7.0%, blood pressure less than 130/80 mm Hg, and low-density lipoprotein (LDL) cholesterol less than 100 mg/dL, respectively. RESULTS The prevalence of diagnosed diabetes was 6.5% from 1999 to 2002 and 7.8% from 2003 to 2006 (P < .05) and increased significantly in women, non-Hispanic whites, and obese people. Although there were no significant changes in the pattern of antidiabetic treatment, the age-adjusted percentage of people with diagnosed diabetes achieving glycemic and LDL targets increased from 43.1% to 57.1% (P < .05) and from 36.1% to 46.5% (P < .05), respectively. Glycosylated hemoglobin decreased from 7.62% to 7.15% during this period (P < .05). The age-adjusted percentage achieving all 3 targets increased insignificantly from 7.0% to 12.2%. CONCLUSIONS The prevalence of diagnosed diabetes increased significantly from 1999 to 2006. The proportion of people with diagnosed diabetes achieving glycemic and LDL targets also increased. However, there is a need to achieve glycemic, blood pressure, and LDL targets simultaneously.

Prevalence, Treatment, and Control of Diagnosed Diabetes in the U.S. National Health and Nutrition Examination Survey 1999-2004

PURPOSE This study aimed to examine the trends in prevalence, treatment, and control of diagnosed diabetes in United States adults 20 years of age or older. METHODS Data from the National Health and Nutrition Examination Survey 1999-2004 were used. Glycemic, blood pressure, and total cholesterol target levels were defined as having glycosylated hemoglobin <7.0%, blood pressure <130/80 mm Hg, and total cholesterol <200 mg/dL, respectively. RESULTS The prevalence of diagnosed diabetes was 7.8% in 2003-2004 and increased significantly in people aged 40-59 years, women, non-Hispanic whites, and obese people in the period 1999-2004. Although there was no significant change in the pattern of antidiabetic treatment, the age-adjusted percentage of people with diagnosed diabetes achieving glycemic and blood pressure target levels increased from 35.8% to 57.1% (p = 0.002) and from 35.7% to 48.3% (p = 0.04), respectively. However, there were only insignificant increases in percentages of those persons achieving total cholesterol target level (from 48.8% to 50.4%) and those achieving all 3 target levels (from 7.5% to 13.2%). CONCLUSIONS In 1999-2004, the prevalence of diagnosed diabetes increased significantly in some subgroups of the population. However, the increases in percentages of people with diabetes achieving glycemic and blood pressure targets are encouraging, although there is room for improvement.

Gender Difference in Blood Pressure Control and Cardiovascular Risk Factors in Americans With Diagnosed Hypertension

Hypertension is an important risk factor for cardiovascular disease, which is the leading cause of death in women. We, therefore, analyzed gender-specific trends in the control of blood pressure and prevalence of 5 other cardiovascular risk factors (central obesity, elevated total cholesterol, low high-density lipoprotein cholesterol, hyperglycemia, and smoking) among adults with diagnosed hypertension in the United States. We included 3475 participants aged ≥18 years with diagnosed hypertension in the National Health and Nutrition Examination Survey 1999–2004. The age-adjusted prevalence of uncontrolled blood pressure was 50.8±2.1% in men and 55.9±1.5% in women, which were not significantly different and had not changed significantly with time. Central obesity, elevated total cholesterol level, and low high-density lipoprotein cholesterol were significantly more prevalent in women than in men (79.0±1.0%, 61.3±1.6%, and 39.7±1.6% versus 63.9±1.6%, 48.1±1.8%, and 35.6±1.7%, respectively; P<0.05). The age-adjusted proportion with ≥3 of the 6 risk factors studied was higher in women than in men (52.5±1.4% versus 40.9±1.8%; P<0.001), and this proportion decreased significantly by 7.7% in women from 1999–2000 to 2003–2004 (P<0.05) but not in men. Our study shows that blood pressure control in women with diagnosed hypertension was not significantly inferior compared with men and had not changed significantly in 1999–2004. However, women had higher prevalence of other concomitant cardiovascular risk factors. Although there is room for improvement in blood pressure control, our study has highlighted the importance of addressing concomitant cardiovascular risk factors in women with hypertension.

High Plasma Level of Fibroblast Growth Factor 21 Is an Independent Predictor of Type 2 Diabetes: A 5.4-year population-based prospective study in Chinese subjects

OBJECTIVE To investigate whether circulating levels of fibroblast growth factor 21 (FGF21), which previously has been shown to be elevated in obesity, could predict the development of type 2 diabetes in a 5.4-year, population-based, prospective study. RESEARCH DESIGN AND METHODS Baseline plasma FGF21 levels were measured using an enzyme-linked immunosorbent assay in 1,900 subjects from the Hong Kong Cardiovascular Risk Factor Prevalence Study (CRISPS). The prospective association of FGF21 with diabetes development over 5.4 years was analyzed using multiple logistic regression. RESULTS At baseline, plasma levels of FGF21 increased progressively with worsening dysglycemia from normal glucose tolerance, through prediabetes, to diabetes (global trend, P < 0.001). Of 1,292 subjects without diabetes at baseline, a high baseline FGF21 level was a strong independent predictor for diabetes development (odds ratio 1.792; P < 0.01), together with waist circumference and fasting plasma glucose levels. CONCLUSIONS Plasma FGF21 levels were significantly increased in subjects with prediabetes and diabetes and predicted the development of diabetes in humans.

Prevalence, Awareness, Treatment, and Control of Hypertension: United States National Health and Nutrition Examination Survey 2001–2002

The prevalence, awareness, treatment, and control of hypertension in the United States are analyzed using the National Health and Nutrition Examination Survey (NHANES) database covering the period 1988–2002. Mean body mass index was 26.1±0.1 kg/m2 in 1988–1991 and 27.9±0.2 kg/m2 in 2001–2002 (p<0.001). In the same period, the prevalence of diabetes mellitus increased from 5.0% to 6.5% (p=0.03). Diastolic blood pressure was 73.3±0.2 mm Hg in 1988–1991 and 71.6±0.4 mm Hg in 2001–2002 (p<0.001). Among the 18–39 years and 60 years and older age groups, the prevalence of hypertension increased significantly since 1988–1991. Multiple regression shows age, body mass index, and being non‐Hispanic black were significantly associated with hypertension. In the period 1988–2002, the percentage receiving treatment and the percentage with blood pressure controlled increased significantly. In 2001–2002, significantly more people with hypertension and diabetes reached a blood pressure target of <130/85 mm Hg. Overall, the control rates were low, especially among middle‐aged Mexican‐American men (8%).

Obesity susceptibility genetic variants identified from recent genome-wide association studies: implications in a chinese population.

CONTEXT Recent large-scale genome-wide association studies identified novel genetic variants associated with obesity and body mass index (BMI) in addition to the well-described FTO and MC4R genetic variants. OBJECTIVE This study aimed to examine 13 previously reported obesity and/or BMI-associated loci for associations with obesity in Chinese. DESIGN AND STUDY PARTICIPANTS This was a cross-sectional case-control study in 470 obese cases (BMI > or =27.5 kg/m(2)) and 700 normal-weight controls (18.5 < or = BMI < or = 23.0 kg/m(2)). RESULTS A significant association with obesity could be replicated (one tailed P < 0.05) in seven of the 13 single-nucleotide polymorphisms (SNPs) in the case-control study. These included GNPDA2 rs10938397 (P = 7.3 x 10(-4)); FTO rs8050136 (P = 8 x 10(-4)); MC4R rs17782313 (P = 1.2 x 10(-3)); KCTD15 rs29941 (P = 8 x 10(-3)); SFRS10-ETV5-DGKG rs7647305 (P = 0.023); SEC16B-RASAL2 rs10913469 (P = 0.041); and NEGR1 rs3101336 (P = 0.046). Combined genetic risk scores were calculated, and we observed ORs ranging from 1.17 to 1.23 for each unit increase in the genetic risk scores. Associations with obesity-related quantitative traits were analyzed separately for cases and controls. KCTD15 SNP rs29941 (P = 1 x 10(-3)) was significantly associated with fasting glucose in the control group, whereas only the FTO SNP rs8050136 was associated with BMI (P = 3.5 x 10(-3)) in the obese group. However, in an extension study of 1938 subjects from the population-based Hong Kong Cardiovascular Risk Factors Prevalence Study, rs8050136, rs10938397, and rs17782313 showed significant associations with BMI. CONCLUSION We have succeeded in replicating, in a Chinese population, the associations with obesity in seven SNPs reported in recent genome-wide association studies. Further functional and fine-mapping studies to elucidate the roles of these putative obesity-related genes and genetic variants are warranted.

Urotensin II : Its function in health and its role in disease

Urotensin II (U-II) is the most potent vasoconstrictor known, even more potent than endothelin-1. It was first isolated from the fish spinal cord and has been recognized as a hormone in the neurosecretory system of teleost fish for over 30 years. After the identification of U-II in humans and the orphan human G-protein-coupled receptor 14 as the urotensin II receptor, UT, many studies have shown that U-II may play an important role in cardiovascular regulation. Human urotensin II (hU-II) is an 11 amino acid cyclic peptide, generated by proteolytic cleavage from a precursor prohormone. It is expressed in the central nervous system as well as other tissues, such as kidney, spleen, small intestine, thymus, prostate, pituitary, and adrenal gland and circulates in human plasma. The plasma U-II level is elevated in renal failure, congestive heart failure, diabetes mellitus, systemic hypertension and portal hypertension caused by liver cirrhosis. The effect of U-II on the vascular system is variable, depending on species, vascular bed and calibre of the vessel. The net effect on vascular tone is a balance between endothelium-independent vasoconstriction and endothelium-dependent vasodilatation. U-II is also a neuropeptide and may play a role in tumour development. The development of UT receptor antagonists may provide a useful research tool as well as a novel treatment for cardiorenal diseases.

Association of genetic variants in the adiponectin gene with adiponectin level and hypertension in Hong Kong Chinese

OBJECTIVE Low plasma adiponectin level can predict the development of hypertension after 5 years in our population. We therefore investigated whether single-nucleotide polymorphisms (SNPs) in the adiponectin gene influenced plasma adiponectin level and whether they were associated with hypertension. DESIGN AND METHODS We genotyped 14 tagging SNPs in 1616 subjects with persistent normotensive or hypertensive status during a 6.4-year follow-up period in the Hong Kong Cardiovascular Risk Factor Prevalence Study-2 (CRISPS-2). Plasma adiponectin level was measured in 1385 subjects using in-house sandwich ELISA. RESULTS The minor G allele of the SNP rs266729 was significantly associated with higher odds of hypertension (odds ratio (95% confidence interval)=1.49 (1.13-1.95), P=0.0044) after adjusting for covariates. In stepwise multiple logistic regression, this SNP (P=0.006) was a significant independent factor of hypertension, together with age (P<0.001), body mass index (P<0.001), triglycerides (P=0.021), and insulin resistance index (P<0.001). Among the 14 SNPs, rs266729 (beta=-0.067, P=0.0037), -10677C>T (beta=0.069, P=0.0027), rs182052 (beta=-0.097, P<0.0001), and rs12495941 (beta=0.103, P<0.0001) were significantly associated with adiponectin level after adjusting for covariates. No significant sex interaction was found for the associations of SNPs with hypertension and adiponectin level. Similar results were obtained in haplotype analysis. CONCLUSION In our population, genetic variants in the adiponectin gene influenced plasma adiponectin levels, and one of them was associated with hypertension. This study has provided further evidence for a role of adiponectin in the development of hypertension.

Prevalence of the Metabolic Syndrome in the United States National Health and Nutrition Examination Survey 1999–2002 According to Different Defining Criteria

The authors studied the prevalence of the metabolic syndrome in the 1999‐2002 National Health and Nutrition Examination Survey (NHANES) according to the World Health Organization, National Cholesterol Education Program (NCEP), and International Diabetes Federation (IDF) definitions. There was 92.9% agreement between the NCEP and IDF definitions. The IDF prevalence was higher (p=0.001) due to more men fulfilling its criteria than the NCEPs (39.9+1.7% vs. 33.6+1.6%; p=0.007). If central obesity were not a prerequisite, the IDF prevalence would increase slightly to 40.3+1.1 %. Subjects categorized as having the metabolic syndrome under IDF but not NCEP tended to be men, younger, and leaner. Their prevalence of self‐reported coronary heart disease was not significantly different from that of other metabolic syndrome patients. Whether waist circumference is a prerequisite does not affect the diagnosis of the metabolic syndrome in the United States. The IDF definition identifies additional individuals at risk for cardiovascular disease.