Migration, blood pressure pattern, and hypertension: the Yi Migrant Study.

Rural-urban migration provides an ideal opportunity to examine the effects of environment and genes on blood pressure. The effect of migration on the Yi people of China was studied. The Yi people live in a remote mountain area in southwestern China. In 1989, blood pressure was measured in 14,505 persons (8,241 Yi farmers, 2,575 urban Yi migrants, and 3,689 Han urban residents) aged 15-89 years. Different patterns were seen for men and women. Among the men, Yi farmers had the lowest mean blood pressure, the least rise in blood pressure with age (systolic blood pressure, 0.13 mmHg/year; diastolic blood pressure, 0.23 mmHg/year), and the lowest prevalence of hypertension (0.66%). In contrast, both Yi migrant men and Han men had higher levels of mean blood pressure, rise in blood pressure with age (Yi migrants: systolic pressure, 0.33 mmHg/year; diastolic pressure, 0.33 mmHg/year; Han: systolic pressure, 0.36 mmHg/year; diastolic pressure, 0.23 mmHg/year), and prevalence of hypertension (Yi migrants, 4.25%; Han, 4.91%). Among the women, however, mean systolic pressure was higher in Yi farmers than in Yi migrants or in Han. Diastolic pressure was similar among the three groups. However, the Yi farmer women's age-related rise in blood pressure (systolic pressure, 0.06 mmHg/year; diastolic pressure, 0.14 mmHg/year) and their prevalence of hypertension (0.33%) were lower than those in the other two groups. Yi migrant women had an intermediate rise in blood pressure with age (systolic pressure, 0.37 mmHg/year; diastolic pressure, 0.23 mmHg/year) and prevalence of hypertension (2.40%). Han women had the greatest rise in blood pressure with age (systolic pressure, 0.56 mmHg/year; diastolic pressure, 0.36 mmHg/year) and the highest prevalence of hypertension (4.76%). For both men and women, the above differences were only partially explained by age, body mass index, heart rate, smoking, and alcohol use. This study, using standardized methods, demonstrates an important effect of migration on rise in blood pressure with age and on the prevalence of hypertension.     

四川省凉山彝族和汉族人群血压与胰岛素关系的研究

目的探讨不同民族人群血胰岛素与血压的关系，探讨是否胰岛素升高血压的作用存在民族差异。方法１９９６年１０～１２月，在凉山彝族自治州西昌市、布拖县和昭觉县的城镇和农村，整群抽样选择男性彝族农民、彝族移民和汉族居民作为研究对象，测量收缩压、舒张压、身高、体重和血胰岛素等指标。结果彝族农民的收缩压和舒张压水平显著低于彝族移民和汉族居民，彝族移民和汉族居民的收缩压和舒张压水平差异无显著性。彝族农民和彝族移民的血胰岛素水平差异无显著性，分别为９．０７８μＩＵ／ｍｌ和８．８９２μＩＵ／ｍｌ，但均显著高于汉族居民（６．５７７μＩＵ／ｍｌ）。多元回归分析结果表明，除彝族移民血胰岛素与收缩压呈弱相关外，各组人群血胰岛素与收缩压和舒张压均无显著性相关。结论进一步表明胰岛素与血压之间的联系尚不确定，提示血胰岛素影响血压的独立效应可能很小。     

高血压病低发区彝、汉族农民饮食调查及其血、尿生化指标研究

本文对高血压病低发区贵州威宁彝、汉族农民55人进行了饮食调查,并对173人作了有关营养的血、尿生化指标测定和分析。结果表明蛋白质、脂肪、碳水化合物等三大主要营养素与血压的关系尚不能找到一致规律,高钾低钠饮食可能与本组高血压低发有关,特别是摄入的和尿中Na/K比值与血压关系更为密切。钙与血压的关系比较复杂,若钙镁摄入量比例适度对高血压的防治具有意义。脂类代谢与血压可能存在一定内在联系,而吸烟程度与血压有较肯定的关系。     

Higher blood pressure among Inuit migrants in Denmark than among the Inuit in Greenland

STUDY OBJECTIVE: Previous studies of blood pressure among the Inuit have given inconsistent results and studies comparing Inuit migrants with those living in traditional Inuit areas are absent. The purpose of the study was to compare the blood pressure of the Inuit in Greenland with that of Inuit migrants in Denmark. DESIGN: Questionnaire, interview, and clinical examination in a cross sectional random population sample. SETTING: A population based survey among Inuit in Greenland and Inuit migrants in Denmark. Participants: 2046 Inuit aged >/or =18, 61% of the sample. MAIN RESULTS: Age and gender adjusted blood pressures were 117/72 mm Hg in Greenland and 127/81 mm Hg among the migrants (p<0.001). In both populations, blood pressure increased with age and body mass index, and was higher among men and non-smokers. In Greenland, blood pressure increased with the level of school education. The associations with Inuit heritage, alcohol, diet, and physical activity were not significant. The difference between the two populations persisted after adjusting for age, gender, body mass index, education, and smoking. Among those who had completed high school, there was no difference between the systolic blood pressure of the two populations while the difference for diastolic blood pressure was much less than for those with less education. CONCLUSIONS: Blood pressure was lower among the Inuit in Greenland than among the Inuit migrants in Denmark but the difference was absent (systolic pressure) or reduced (diastolic pressure) among the better educated. The results suggest that the blood pressure of the Inuit, especially Inuit men, may be responsive to factors related to the modern Western way of life.     

Salt and blood pressure in Belgium.

Blood pressure, pulse rate, body weight, and height were measured on two occasions in the inhabitants of a random 10% sample of households in a Belgian village. Twenty-four-hour urinary excretion of creatinine, sodium, and potassium was also determined. In subjects over the age of 19 there was a significant correlation for both systolic and diastolic pressure with age and body weight and, in women, also with pulse rate. After adjusting for these three variables, the systolic blood pressure in men was negatively correlated with the daily urinary potassium excretion, and the diastolic blood pressure in women negatively with the urinary sodium: creatinine ratio. The present data, obtained within one society, do not support a role for dietary sodium in the distribution of blood pressure within this population. Comparison of the present results with data from other countries does not refute the salt-genetic hypothesis but suggests also that a high potassium intake may lower blood pressure.     

Blood pressure and urinary cations in urban Bantu of Zaire

The 24-hour urinary excretion of sodium, potassium, calcium, and magnesium and their relationship to arterial blood pressure were investigated from December 1983 to May 1984 in a 10% random sample (n = 666) of urban Bantu of Kinshasa, Za?re. In youths aged 10-19 years, blood pressure averaged 109/60 mmHg, and the 24-hour urinary excretion of sodium, potassium, calcium, and magnesium averaged 84 mmol, 30 mmol, 483 mumol, and 2 mmol, respectively. After adjustment for age and body weight, a weak positive association became apparent between diastolic pressure and the urinary sodium to potassium ratio in girls and all youths. In adults aged greater than or equal to 20 years, blood pressure averaged 124/72 mmHg, and the 24-hour urinary excretion of sodium, potassium, calcium, and magnesium averaged 87 mmol, 33 mmol, 828 mumol, and 1.88 mmol, respectively. After adjustment for sex, age, body weight, and pulse rate in all adults, systolic pressure was significantly and positively correlated with urinary sodium excretion and negatively correlated with urinary potassium excretion, while diastolic pressure was weakly associated with urinary calcium excretion. In women, an independent and significant association was also observed between systolic pressure and 24-hour urinary sodium. When instead of the 24-hour urinary excretion of sodium and potassium, the sodium to potassium ratio was considered as an independent variable in multiple regression analysis, both systolic and diastolic pressure were independently and positively related to the sodium to potassium ratio in all adults. These results indicate that in this urban Bantu population, age and body weight are the major predictors of systolic pressure in youths and the major predictors of both systolic and diastolic pressure in adults. The sodium to potassium ratio did contribute to the prediction of blood pressure in girls and when, in youths as well as in adults, both sexes were considered together. Urinary calcium was associated with diastolic pressure only in all adults.     

四川彝族人群原发性高血压移民流行病学调查

目的比较四川省凉山彝族农民与移民原发性高血压患病率水平及其影响因素。方法2007-2008年对四川凉山地区(包括西昌市、金阳县、昭觉县、布拖县、喜德县、德阳县、宁南县)彝族人群进行问卷调查及血样生化检测,对原发性高血压可能危险因素进行多因素非条件Logistic回归分析。结果彝族农民原发性高血压患病率为3.19%,其中男性为4.73%,女性为1.92%。彝族移民原发性高血压患病率为15.10%,其中男性为17.74%,女性为10.83%。彝族农民和移民血压正常高值分别为12.53%(男性为16.05%,女性为9.68%)和25.93%(男性为32.65%,女性为16.52%)。年龄和糖尿病是彝族农民原发性高血压危险因素。年龄、超重或肥胖是彝族移民原发性高血压危险因素,而血压尿酸异常是其保护因素。结论彝族农民移居城镇后,生活环境发生变化,原发性高血压患病风险增加。     

Effects of alcohol consumption and other lifestyle behaviors on blood pressure for the middle-aged and elderly in the Guangxi Hei Yi Zhuang and Han populations.

Han is the largest group and Zhuang is the largest minority among the 56 ethnic groups in China. Geographically and linguistically, Zhuang can be classified into 43 ethnic subgroups, in which Hei Yi Zhuang is proved to be the most conservative subgroup. Little is known about the relationship between alcohol consumption and blood pressure levels in this population. Therefore, the present study was undertaken to compare the effects of alcohol consumption and other lifestyle behaviors on blood pressure levels for the middle-aged and elderly in the Guangxi Hei Yi Zhuang and Han populations. A total of 657 subjects of Hei Yi Zhuang aged 40 and older were surveyed by a stratified randomized cluster sampling. Information on demography, diet, and other lifestyle factors was collected by standard questionnaires. Anthropometric parameters and serum lipid levels were also obtained in all subjects. The results were compared with those in 520 participants of Han Chinese from the same region. The levels of systolic blood pressure and pulse pressure in Hei Yi Zhuang were higher than those in Han (P < .01-.001). Hypertension was positively correlated with sex (male), age, physical activity, alcohol consumption, serum triglyceride levels, and total energy, total fat, and salt intakes, and negatively associated with educational level in Hei Yi Zhuang (P < .05-.001), whereas positively correlated with sex (male), age, physical activity, alcohol consumption, body mass index, waist circumference, serum total cholesterol levels, and total energy, total fat, and salt intakes, and negatively associated with educational level in Han (P < .05-.001). The difference in blood pressure levels between the two ethnic groups might result from different dietary habit, lifestyle, sodium intake, educational level, physical activity, and even genetic factors.     

Nutrition and blood pressure among elderly men and women (Dutch Nutrition Surveillance System)

Associations between blood pressure and nutrition-related variables (body mass index, dietary intake, and 24-hr excretion of sodium, potassium, magnesium, and calcium in the urine) were investigated in men (n = 138) and women (n = 117) 65-79 years old not using drugs known to affect blood pressure and not on a diet. Among men, body mass index was positively and creatinine clearance was inversely associated with systolic blood pressure, whereas body mass index and urinary sodium:potassium ratio were positively associated with diastolic blood pressure. Among women, both age and urinary calcium:creatinine ratio were positively associated with systolic as well as diastolic blood pressure. Coffee consumption was positively correlated with blood pressure and urinary calcium:creatinine ratio among the women. From the results it appears that, besides "normal" weight, increased potassium intake and urinary excretion may exert a protective effect among elderly men against hypertension when sodium exposure is relatively high. The positive association between urinary calcium:creatinine ratio and blood pressure among the women may be partly due to coffee consumption.     

不同民族高血压流行病学因素的调查研究

本文通过对贵州省威宁县不同民族高血压抽样普查,发现回、汉、彝三民族高血压标化患病率分别为4.04%、1.51%、0.70%,三者间存在显著差异。为查明差异的主要原因及对高血压病因作一初步探索,在同一地区对三民族膳食。儿童血压及儿童发育状况作了调查。结果提示,三民族血压差异的根本原因以遗传基因的不同可能性最大,部分环境因素(如钠、钾、维生素C)可能通过遗传因素间接地发生影响。其中,儿童发育。高钾、高维生素C的摄入可能为影响彝族儿童及成人血压的主要原因,而回族则可能和遗传因素有关。     

A prospective study of familial aggregation of blood pressure in young children.

In a prospective study, we evaluated familial aggregation of blood pressure in a sample of 175 normotensive families with children 3 to 6 yr old. Systolic and diastolic blood pressure measurements of parents and children were correlated at 1, 2, and 3 yr intervals. Spearman rank-order correlation coefficients between parents and children were significant for mother-son pairs. In particular, mother-son blood pressure correlation coefficients were significant for systolic blood pressure across all 3 yr and for diastolic blood pressure during yr 2. Further analyses were performed adjusting for body mass index (BMI), age, physical activity, sodium intake, potassium intake, and parental smoking status, and alcohol use. The Spearman correlation coefficients for mother-son pairs remained significant for yr 1 and 3 after adjusting for these blood pressure correlates. These results are consistent with cross-sectional studies and suggest that both genetic and environmental contributions to blood pressure status are important in young children.     

Longitudinal analysis of the relationship between blood pressure and migration: the Tokelau Island Migrant Study

The Pacific atoll population of Tokelau has been followed since 1968 to assess the health consequences of migration to a western society. The blood pressure of a cohort of 532 adults who were still living in Tokelau in 1976 (nonmigrants) are compared with those of a cohort of 280 adults who had migrated to New Zealand (migrants). Significant differences between migrants and nonmigrants were detected in the rates of change of both systolic and diastolic pressures in men, and in the rates of change of diastolic pressures in women. The age-, body mass, and blood pressure-corrected rates of change were greater in migrants than in nonmigrants, and greater in men than in women. Blood pressures tend to rise 1 mmHg/year faster among male migrants than among male nonmigrants, and about 0.4 mmHg/year faster among female migrants than among female nonmigrants. These findings have clear implications for the health of migrants.     

Blood pressure and its correlates in an African tribe in urban and rural environments.

As part of a longitudinal study of migrants who move from a subsistence farming rural society to Nairobi, blood pressures and associated factors were measured in cross sectional studies of members of the Luo tribe in their traditional rural environment and in the urban environment of Nairobi. Blood pressures in Nairobi correlated with duration of urban residence. In the rural area men showed a negligible rise in blood pressure with age, and both sexes showed a significantly smaller rise than in the urban area. Although mean weights of the rural group were smaller, this did not account for all the urban/rural differences in blood pressures. Nevertheless, mean urinary sodium concentration and sodium ratios (sodium/potassium and sodium/creatinine) were significantly higher in the urban group whereas mean urinary potassium concentration and potassium/creatinine ratio were significantly lower. Perhaps the ratio of sodium to potassium in the diet contributes to the different blood pressure profiles of these two populations.     

Isolated systolic hypertension in 14 communities

In the Hypertension Detection and Follow-up Program, 158,906 individuals from 14 communities around the United States had their blood pressure measured in their homes in 1972-1973. Of the total population screened, 2.4% had isolated systolic hypertension (systolic blood pressure greater than or equal to 160 mmHg and diastolic blood pressure less than 90 mmHg). Isolated systolic hypertension was present for 0.5% of those aged 30-39 years and 6.8% among those aged 60-69 years. The prevalence in blacks and women was greater than the prevalences in both whites and men. The prevalence among those taking antihypertensive medications at the time of screening was 6.1%, and 1.9% among those not on antihypertensive medications. From the individuals with "normal" diastolic blood pressure on the single home measurement (less than 90 mmHg), a random sample of 5,032 individuals were followed for mortality for eight years. Prevalence of isolated systolic hypertension was similar in this sample to that in the total. Among those not on antihypertensive medications, 8-year life table all-cause mortality rates adjusted for age, race, and sex were 17.6% for those with systolic blood pressure greater than or equal to 160 mmHg and 7.7% for those with systolic blood pressure greater than 160 mmHg. Among this population, all of whom had a diastolic blood pressure less than 90 mmHg, a multiple logistic analysis adjusting for baseline treatment status, age, race, sex, education, smoking, weight, pulse, physical activity, and systolic blood pressure revealed that each millimeter increase in systolic blood pressure was associated with approximately a 1% increase in mortality over the eight years of follow-up (p less than 0.05). Isolated systolic hypertension is both relatively common and a significant risk factor for subsequent mortality.     

Increased blood pressure in adolescents who were small for gestational age at birth: a cohort study in Brazil.

BACKGROUND: This paper studies the relationship between birthweight for gestational age and blood pressure in adolescents aged 14-15 years in southern Brazil. METHODS: A sample of 1076 adolescents belonging to a cohort of over 6000 children born in 1982 in Pelotas, southern Brazil, was studied in 1997. All households in a sample of 25% of the city's census tracts were visited and all adolescents born in 1982 were interviewed, weighed, and their blood pressures were measured twice. Data from the adolescents were linked to the database through their names and dates of births. RESULTS: High diastolic and systolic pressure (defined as >95th percentile) were significantly more frequent among adolescents who were born below the 10th percentile of birthweight for gestational age. No association was found between high blood pressure and low birthweight or preterm births. In a multiple linear regression analysis, the association between birthweight for gestational age and blood pressure was not statistically significant after adjusting for age, sex, skin colour and family income. However, when the current body mass index and height were added to the model both diastolic and systolic pressure were significantly associated with birthweight for gestational age, and adolescents who were small for gestational age at birth presented a mean elevation of 3.08 mmHg for diastolic pressure and 2.89 mmHg for systolic pressure. CONCLUSIONS: There is an inverse association between birthweight for gestational age and blood pressure during adolescence. This association, however, is only disclosed when the negative confounding effect of the body mass index is controlled for. The same association is not found when the effects of birthweight and gestational age on blood pressure are analysed separately. It appears therefore that the elevation of blood pressure during adolescence only occurs when there was intra-uterine growth retardation.     

彝族、汉族居民高血压流行病学分析

目的了解四川省凉山州冕宁县彝族地区彝、汉族当地人群高血压的流行病学特征,为凉山彝族地区高血压防治干预提供科学依据。方法采用分层、整群、多阶段随机抽样方法对冕宁县10个乡镇1 388名汉族、677名彝族共计2 065名当地居民进行高血压患病率调查。结果彝族居民高血压患病率为14.62%,标化率为15.29%,血压水平收缩压(SBP)为(119.99±14.55)mm Hg,舒张压(DBP)为(74.06±8.49)mm Hg,汉族居民的患病率为14.19%,标化率15.60%,血压水平为SBP为(118.06±15.91)mm Hg,DBP(74.39±9.70)mm Hg;2个民族血压水平和高血压患病率差异均无统计学意义(P0.05);但同一民族不同性别间差异有统计学意义(P0.01)。随着年龄的增长,高血压患病率呈明显的增高趋势。高血压患病率还与教育程度和劳动强度密切相关。结论冕宁县彝族居民高血压患病率与汉族居民差异无统计学意义。     

Blood pressure and excretion of sodium, potassium, calcium and magnesium in 8- and 9-year old boys from 19 European centres

We have measured systolic and diastolic blood pressure and excretions of sodium, potassium, calcium and magnesium in groups of about 50 8- and 9-year-old boys from 19 European centres using standardized methods for the measurement of blood pressure and collection of urine, and by carrying out all analyses in one laboratory. Weight, height, pulse rate and environmental temperature were also studied. Mean systolic blood pressure ranged from 91 to 105 mm Hg and diastolic blood pressure from 51 to 66 mm Hg. Mean 24-h excretion of sodium was between 91 and 146 mmol/d, that of potassium between 29 and 60 mmol/d, that of calcium between 1.5 and 2.6 mmol/d and that of magnesium between 2.7 and 4.2 mmol/d. Mean sodium excretion tended to be lower and potassium excretion tended to be higher in the boys from the north-western parts of Europe. Relations between either systolic or diastolic blood pressure and electrolyte excretions were generally weak or absent. Most remarkable is that only the association between mean diastolic blood pressure and 24-h magnesium excretion (partial regression coefficient (b +/- s.e., -5.04 +/- 2.08 mm Hg/mmol/d) was statistically significant after adjusting for differences in creatinine excretion and environmental temperature. Mean systolic blood pressure was not significantly related with any of the variables measured. The partial regression coefficient (b +/- s.e.) for diastolic blood pressure on weight was 0.186 +/- 0.062 mm Hg/kg, on height 0.165 +/- 0.056 mm Hg/cm, on pulse rate 0.364 +/- 0.100 mm Hg/beats per min and on outside temperature -0.25 +/- 0.07 mm Hg/degrees C.     

广西黑衣壮族人群高血压患病率调查

目的了解广西黑衣壮族人群高血压的患病情况及其影响因素。方法采用整群抽样方法对1068名≥20岁黑衣壮族人群的血压、身高、体重、体重指数、血脂及载脂蛋白进行测定,并将其结果与933名当地的汉族人群作比较。结果广西黑衣壮族人群高血压的患病率为25.2%,而当地的汉族人群为17.3%(P<0.001);黑衣壮族人群单纯收缩期高血压的患病率也明显高于汉族人群(12.5%vs.3.9%,P<0.001);黑衣壮族人群平均收缩压和脉压水平也显著高于汉族人群(分别为125.20mmHg±18.62mmHgvs.121.88mmHg±15.99mmHg,P<0.001和48.64mmHg±14.75mmHgvs.44.98mmHg±11.12mmHg,P<0.001;1mmHg=0.133kPa)。黑衣壮族人群高血压患病率与甘油三酯、性别和年龄呈显著正相关;而汉族人群高血压患病率则与总胆固醇、性别、年龄和饮酒呈显著正相关。黑衣壮族和汉族人群高血压的知晓率为8.6%vs.21.1%(P<0.001),治疗率4.5%vs.15.5%(P<0.001),控制率1.9%vs.10.6%(P<0.001)。结论广西黑衣壮族人群高血压患病率显著高于汉族人群,可能与其特殊的地理环境、生活方式、过多钠盐的摄入、低文化程度以及遗传因素等有关。高血压知晓率、治疗率和控制率较低,必须采取干预措施。     

Body weight, blood pressure, and electrolyte excretion of young adults from six ethnic groups in Hawaii

There is positive correlation between high dietary intake of sodium and prevalence of hypertensive disease. Dietary potassium shows a negative correlation with this prevalence. Racial background of subjects may affect such relationships. This is a study of the relationships between ethnicity and blood pressure in young adults of six ethnic groups in Hawaii. Body weight, electrolyte excretion, which may reflect intake, and blood pressure of the subjects are reported here. Caucasians and Hawaiians and part-Hawaiian young adults tended to be taller and heavier than the Chinese, Filipinos, Japanese, and Koreans. Both systolic and diastolic pressures were significantly higher in males than in females (all races combined). No significant differences between sexes or races were found in urinary excretion of sodium and potassium or in urinary sodium:potassium ratios. Body weight and Quetelet's Index but not sodium:potassium ratio correlated significantly with diastolic pressure.     

Effects of volume expansion and contraction on potassium homeostasis in normal and hypertensive humans

To investigate the role of potassium on blood pressure we measured serum potassium, urinary excretion of potassium and sodium, fractional excretion of potassium, urinary sodium:potassium ratio, plasma renin activity, aldosterone, and norepinephrine during dynamic maneuvers in normotensive and hypertensive subjects. After baseline measurements, we expanded intravascular volume with infusion of intravenous saline and then induced sodium and volume depletion by diuretic administration during a low sodium salt diet. These studies were performed in 431 normotensive and 478 hypertensive subjects enabling evaluation of the effects of age, race, and sex, as well as blood pressure, on the results. Among normotensives, we found that white subjects had significantly P less than 0.05) higher levels of serum and urine potassium, fractional potassium excretion and lower urinary sodium:potassium ratios than black subjects and that males had the same patterns of differences compared to females. Similar, but less consistent racial differences were seen among the hypertensive subjects. We also observed significant (P less than .05) correlations between urinary potassium excretion and body weight in both normal and hypertensive groups. In normal subjects, a significant correlation was observed between the urinary sodium:potassium ratio and blood pressure that was not seen in the hypertensives. The latter, however, displayed a significant (P less than .05) inverse relationship between serum potassium and blood pressure. Multiple regression analysis revealed that urinary potassium excretion was influenced by age, race, sex, body weight, blood pressure, creatinine clearance, renin, and aldosterone. These observations reveal important relationships between potassium homeostasis and blood pressure control that deserve further study.