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1.
Although an inverse relationship between body mass index (BMI) and baroreflex sensitivity (BRS) was found, the effect of waist circumference (WC) on BRS is still inconclusive. The contradictory results of previous studies may be related to the heterogeneity and relatively small sample size of the subjects examined. The aim of this population-based study was to investigate whether the influence of increased WC is more detrimental to BRS than BMI. A total of 760 community dwellers were recruited and they were classified into Q1 (n = 189), Q2 (n = 183), Q3 (n = 192) and Q4 (n = 196) groups, based on WC quartiles. Spontaneous BRS was determined by spectral α coefficient method. Valsalva ratio was the longest RR interval after release of Valsalva maneuver divided by the shortest RR interval during maneuver. Cardiac autonomic function was calculated by power spectrum of heart rate in low and high frequency (LF, 0.04–0.15 Hz; HF, 0.15–0.40 Hz), and LF/HF ratio in supine position for five minutes. There were significant differences in spontaneous BRS and Valsalva ratio among different WC groups. In multivariate analysis, obesity was inversely associated with spontaneous BRS and Valsalva ratio. However, these inverse relationships became insignificant after further adjustment for WC quartiles. In contrast, Q4 vs. Q1, Q3 vs. Q1 and Q2 vs. Q1 of WC were inversely related to spontaneous BRS. Q4 vs. Q1 and Q3 vs. Q1 of WC were negatively associated with the Valsalva ratio. In conclusion, increased and even high-normal WC had a stronger adverse effect on BRS than BMI, independent of cardio-metabolic risk factors.  相似文献   
2.
AimsTo explore the association between WWI and the incidence of HTN in the Rural Chinese Cohort Study.Methods and ResultsWe examined data for 10,338 non-hypertensive participants (39.49% men) aged ≥ 18 years from the Rural Chinese Cohort Study who completed a baseline examination during 2007–2008 and follow-up during 2013–2014. WWI was calculated as waist circumference (cm) divided by the square root of weight (kg). Multiple logistic regression models were used to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for the probability of HTN across four WWI categories. Restricted cubic splines analysis was used to model the dose–response association of WWI and HTN. A total of 2078 participants had HTN during a median follow-up of 6 years. After adjusting for potential confounders, as compared with the lowest WWI category (<9.94 cm/√kg), with WWI 9.94 to 10.42, 10.42 to 10.91 and ≥ 10.91 cm/√kg, the ORs (95% CIs) for HTN were 1.12 (0.93–1.35), 1.40 (1.17–1.69) and 1.50 (1.24–1.82), respectively. Results of the sensitivity analyses were robust. The ORs were generally consistent on subgroup analysis by sex, smoking status, systolic blood pressure and diastolic blood pressure. Multiple logistic regression models with restricted cubic splines showed a non-linear positive association between WWI and HTN (Pnonlinearity < 0.001).ConclusionThe highest WWI category was significantly associated with increased risk of HTN. Our findings may facilitate the development and promotion of obesity prevention strategies aimed at reducing the risk of HTN and provide evidence for healthcare policy in rural China.  相似文献   
3.
BACKGROUND: The HOXA1 gene plays a major role in brainstem and cranial morphogenesis. The G allele of the HOXA1 A218G polymorphism has been previously found associated with autism. METHODS: We performed case-control and family-based association analyses, contrasting 127 autistic patients with 174 ethnically matched controls, and assessing for allelic transmission disequilibrium in 189 complete trios. RESULTS: A, and not G, alleles were associated with autism using both case-control (chi(2) = 8.96 and 5.71, 1 df, p <.005 and <.025 for genotypes and alleles, respectively), and family-based (transmission/disequilibrium test chi(2) = 8.80, 1 df, p <.005) association analyses. The head circumference of 31 patients carrying one or two copies of the G allele displayed significantly larger median values (95.0th vs. 82.5th percentile, p <.05) and dramatically reduced interindividual variability (p <.0001), compared with 166 patients carrying the A/A genotype. CONCLUSIONS: The HOXA1 A218G polymorphism explains approximately 5% of the variance in the head circumference of autistic patients and represents to our knowledge the first known gene variant providing sizable contributions to cranial morphology. The disease specificity of this finding is currently being investigated. Nonreplications in genetic linkage/association studies could partly stem from the dyshomogeneous distribution of an endophenotype morphologically defined by cranial circumference.  相似文献   
4.
AIMS: Different criteria have been proposed by the World Health Organization (WHO) and by the Third Report of the National Cholesterol Education Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults (ATPIII) for the diagnosis of the metabolic syndrome. Its identification is of particular importance for coronary risk assessment. METHODS: The prevalence of the metabolic syndrome was determined according to the two different proposals in 1569 consecutive subjects with Type 2 diabetes. RESULTS: By the WHO proposal, 81% of cases (95% confidence interval, 79-83) were labelled as metabolic syndrome. Microalbuminuria had the highest specificity (99%) and visceral obesity the highest sensitivity (93%). Seventy-eight per cent of patients (95% CI, 76-80) fulfilled the ATPIII criteria for metabolic syndrome, low HDL-cholesterol having the highest specificity (95%), elevated blood pressure having the highest sensitivity. According to both proposals, 1113 patients were positive; 183 were concordantly negative, indicative of a fairly good agreement (k statistics, 0.464). Subjects only positive for the WHO proposal were more frequently males, had a lower BMI and a higher arterial pressure. Only subjects identified by the ATPIII proposal had a significantly higher prevalence of previously detected coronary heart disease. CONCLUSIONS: Minimum criteria for the metabolic syndrome are met in most patients with Type 2 diabetes. Correct identification of the syndrome is important for an integrated approach to reduce the high costs and the associated disabilities. The ATPIII proposal more clearly identifies the burden of coronary heart disease associated with the metabolic syndrome.  相似文献   
5.
Physical inactivity, excess adiposity and premature mortality   总被引:5,自引:0,他引:5  
The purpose of this report is to review the evidence that physical inactivity and excess adiposity are related to an increased risk of all‐cause mortality, and to better identify the independent contributions of each to all‐cause mortality rates. A variance‐based method of meta‐analysis was used to summarize the relationships from available studies. The summary relative risk of all‐cause mortality for physical activity from the 55 analyses (31 studies) that included an index of adiposity as a covariate was 0.80 [95% confidence interval (CI) 0.78–0.82], whereas it was 0.82 [95% CI 0.80–0.84] for the 44 analyses (26 studies) that did not include an index of adiposity. Thus, physically active individuals have a lower risk of mortality by comparison to physically inactive peers, independent of level of adiposity. The summary relative risk of all‐cause mortality for an elevated body mass index (BMI) from the 25 analyses (13 studies) that included physical activity as a covariate was 1.23 [95% CI 1.18–1.29], and it was 1.24 [95% CI 1.21–1.28] for the 81 analyses (36 studies) that did not include physical activity as a covariate. Studies that used a measure of adiposity other than the BMI show similar relationships with mortality, and stratified analyses indicate that both physical inactivity and adiposity are important determinants of mortality risk.  相似文献   
6.
老年2型糖尿病患者胰岛素抵抗相关指标的检测和意义   总被引:1,自引:1,他引:0  
目的:探讨老年2型糖尿病胰岛素抵抗(IR)及其相关性,为老年2型糖尿病的合理防治提供临床依据。方法:选择120例老年2型糖尿病患者,按胰岛素敏感指数(HOMA)胰岛素抵抗(HOMA-IR)50百分位点将患者分为两组:胰岛素相对敏感组(HOMA-IR<3.56)和胰岛素相对抵抗组(HOMA-IR≥3.56),比较体重指数(BMI)、腰/臀比(WHR)、血压、血生化学检查等指标。用年龄>40岁,<60岁的2型糖尿病患者做对照组。结果:两组老年患者在年龄、性别、舒张压、空腹血糖、胆固醇、高密度脂蛋白、糖化血红蛋白、HOMA胰岛β细胞功能方面无差异;但BMI、WHR、收缩压、甘油三脂、空腹胰岛素、HOMA-IR差异具有显著性。多线性回归分析后,只有腰/臀比、收缩压、甘油三脂、HOMA-IR存在统计学差异。老年患者与对照组相比,IR发生率明显增加,且两者腰/臀比、收缩压、甘油三脂方面也差异显著。结论:IR与老年2型糖尿病密切相关,是临床防治糖尿病的重要靶点。  相似文献   
7.
北京城区居民体质指数与慢性病危险因素关系分析   总被引:9,自引:0,他引:9  
对 1 995~ 1 998年营养与食品安全所老年与临床营养室在北京地区慢性病社区防治研究中积累的1 2 4 6例 2 5~ 74岁居民的部分体检资料进行分析 ,观察不同人群体质指数 (BMI)、腰围 (WC)水平与慢性疾病相关因素 血清总胆固醇 (TC)、高密度脂蛋白胆固醇 (HDL C)、甘油三酯 (TG)、收缩压 (SBP)、舒张压 (DBP)、血糖 (FBG)及与高血压、高脂血症、糖尿病的检出率的关系。结果 :该人群超重及肥胖率男性为 41 7%及1 4 6 % ,女性为 32 0 %及 2 0 4%。超重及肥胖组高血压、高脂血症、糖尿病的检出率明显高于BMI正常组。相关分析结果表明BMI、WC与TC、TG、SBP、DBP呈显著正相关 ;与HDL C、HDL C TC呈显著负相关 ,WC与FBG呈显著正相关。提示为早期预防慢性病 ,应对BMI>2 4的人群给予充分关注  相似文献   
8.
目的观察以宗四维牵引和熏腰蒸气疗法治疗腰椎间盘突出症的临床疗效。方法应用仰卧纵轴骨盆牵引,俯卧骨盆牵引同时外展患肢牵引,仰卧屈曲双下肢悬吊牵引,俯卧过伸双下肢悬吊牵引,根据患者椎曲的改变类型辩证施治;牵引后进行熏腰蒸气治疗。结果腰椎间盘突出症治疗有效率为93%,无效率7%。  相似文献   
9.
Head circumference is considered an important parameter of brain growth and development. Syndrome-specific standards for head circumference in Williams-Beuren syndrome (WBS) are not available to date, although mental retardation is a leading manifestation in the syndrome. Therefore, we investigated head growth in 63 girls (251 measurements) and 88 boys (298 measurements) with WBS between birth and adulthood. Most measurements in both sexes were from the first 4 years of life (n = 162 in girls and n = 189 in boys). Mean (±SD) head circumference at birth was 33.39 ± 1.38 cm and 34.02 ± 1.44 cm for term girls and boys, respectively. Although head growth in WBS girls and boys was at a slower velocity, the pattern of head circumference was similar to that in the normal population. After the age of 3 months, head circumference started to fall below the normal mean in girls (0.5–2 cm). In boys, mean head circumference was below the normal mean already at 1 month of age (2 cm). The deficit increased to 3 cm from 6 months to 4 years. Adult OFC was 52.85 ± 1.75 cm (n = 16) compared to 55.70 ± 1.83 cm (n = 46; P < 0.00001) in WBS women and 55.51 ± 1.68 cm (n = 30) compared to 57.87 ± 1.29 cm (n = 31; P < 0.00001) in WBS men. During development, microcephaly is only seen in about one third of WBS patients. © 1994 Wiley-Liss, Inc.  相似文献   
10.
OBJECTIVE—To analyse the distributions of and generate growth charts for stature and occipitofrontal circumference (OFC) in neurofibromatosis 1 (NF1) patients.
DESIGN—Cross sectional database survey.
SETTING—The National Neurofibromatosis Foundation International Database (NFDB) includes clinical information on NF1 patients from 14 participating centres in North America.
SUBJECTS—A total of 569 white, North American, NF1 patients, 55% female and 45% male.
MAIN OUTCOME MEASURES—Stature and OFC measurements of NF1 patients were compared to age and sex matched population norms using z score standardisation and centile curves.
RESULTS—The distributions of stature and OFC are shifted and unimodal among NF1 patients; 13% of patients have short stature (2 standard deviations below the population mean) and 24% have macrocephaly (OFC 2 standard deviations above the population mean).
CONCLUSIONS—Alterations of stature and OFC are not limited to NF1 patients with frank short stature or macrocephaly.


Keywords: neurofibromatosis 1; stature; occipitofrontal circumference; macrocephaly  相似文献   
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