Blood pressure survey on the Navajo Indian reservation

Acculturation to Western society as a risk factor for high blood pressure: a meta-analytic review

OBJECTIVE

A number of studies have documented that acculturation to western society is related to an increase in blood pressure (BP). Although there is evidence that higher socioeconomic status appears related to better cardiovascular health, increasing acculturation to western society appears related to worse cardiovascular health. The purpose of this meta-analysis was to investigate the association between acculturation and BP.

METHODS

Literature searches yielded 125 relevant research manuscripts, which were coded by teams of two independent raters. This study was conducted in 2003 and 2004, and research databases such as MEDLINE and PsychINFO were searched through 2004. Measures of association (effect sizes) were extracted for both systolic blood pressure (SBP) and diastolic blood pressure (DBP) readings. Random effects models were used to analyze the resulting data.

RESULTS

The overall effect sizes associated with acculturation were 0.28 for SBP and 0.30 for DBP, with increasing acculturation to western society related to higher BP. More acculturated individuals had an average of 4 mm Hg higher BP than less acculturated individuals, which is similar to the effect sizes of known risk factors for high BP such as diet and physical activity. The effects of acculturation on BP appear to be universal, with similar effect sizes found across all regions of the world. Change in BP due to acculturation was not related to body mass index (BMI) or cholesterol but was related to length of residence in the new culture, with the largest effect sizes seen on initial entry and then decreasing rapidly within the first few years. Sudden cultural changes, such as migration from rural to urban settings, resulted in the largest effect sizes, which finding supports the hypothesis that the stress of cultural change is important role in the acculturation effect.

CONCLUSIONS

Acculturation to western society is associated with higher BP, and the distress associated with cultural change appears to be more influential than changes in diet or physical activity. Future studies would benefit from investigating how cultural change affects health and examining whether some non-Western cultural values and practices are health protective.

Comorbidity of Alcohol Abuse and Dependence with Medical Conditions in 2 American Indian Reservation Communities

BACKGROUND

The objective was to examine the association of self-reported Diagnostic and Statistical Manual-IV edition alcohol abuse and dependence with medical conditions among American Indians (AIs).

METHODS

We analyzed data previously collected in a large epidemiological study of members of 2 culturally distinct AI tribes from the Southwest (SW; n = 1,446) and the Northern Plains (NP; n = 1,638) living on or near their reservations. Associations of combined self-reported alcohol abuse and alcohol dependence with 19 medical conditions were examined through multinomial logistic regression.

RESULTS

Medical conditions that had significant relationships with alcohol abuse/dependence were sprains and strains [odds ratio (OR) 2.04, p < 0.001], hearing and vision problems (OR 2.05, p < 0.001), kidney and bladder problems (OR 1.55, p < 0.01), head injuries (OR 2.20, p < 0.001), pneumonia/tuberculosis (OR 1.49, p < 0.01), dental problems (OR 1.89, p < 0.001), and liver problems/pancreatitis (OR 2.18, p < 0.001). The total count of medical conditions was also significantly related to alcohol abuse/dependence, with a higher count being associated with the outcome (OR 1.17, p < 0.001).

CONCLUSIONS

In this community-based study of rural AIs, diverse medical conditions were associated with alcohol abuse and dependence. Further research should examine, and confirm, the nature, extent, and tribal variation of the medical consequences of alcohol abuse and dependence in these unique populations.

The epidemiology of atherosclerosis and its risk factors among Native Americans

In the past, the rates of risk factors for atherosclerosis and cardiovascular disease (CVD) as well as the manifestations of coronary heart disease, stroke, and peripheral vascular disease in Native Americans have been relatively low compared to the general United States population. However, over the past several decades the rates of these CVD-associated risk factors have markedly increased with the concomitant development of a significant and alarming rise in the manifestations of atherosclerosis.

Uranium mining and lung cancer among Navajo men in New Mexico and Arizona, 1969 to 1993

Navajo men who were underground miners have excess risk of lung cancer. To further characterize the long-term consequences of uranium mining in this high-risk population, we examined lung cancer incidence among Navajo men residing in New Mexico and Arizona from 1969 to 1993 and conducted a population-based case-control study to estimate the risk of lung cancer for Navajo uranium miners. Uranium mining contributed substantially to lung cancer among Navajo men over the 25-year period following the end of mining for the Navajo Nation. Sixty-three (67%) of the 94-incident lung cancers among Navajo men occurred in former uranium miners. The relative risk for a history of mining was 28.6 (95% confidence interval, 13.2-61.7). Smoking did not account for the strong relationship between lung cancer and uranium mining. The Navajo experience with uranium mining is a unique example of exposure in a single occupation accounting for the majority of lung cancers in an entire population.

The epidemic of obesity in American Indian communities and the need for childhood obesity-prevention programs

American Indians of all ages and both sexes have a high prevalence of obesity. The high prevalence of diabetes mellitus in American Indians shows the adverse effects that obesity has in these communities. Obesity has become a major health problem in American Indians only in the past 1-2 generations and is believed to be associated with the relative abundance of high-fat foods and the rapid change from active to sedentary lifestyles. Intervention studies are urgently needed in American Indian communities to develop and test effective strategies for weight reduction. The poor success rate of adult obesity treatment programs in the general population points to the need to develop prevention approaches aimed toward children. Because eating and physical activity practices are formed early in life and may be carried into adulthood, prevention programs that encourage increased physical activity and healthful eating habits targeted toward young people need to be developed and tested. To be most effective, interventions must be developed with full participation of the American Indian communities.

Hypertension in Alaska Natives: association with overweight, glucose intolerance, diet and mechanized activity

OBJECTIVE

Determine the prevalence of hypertension in Alaska Natives and evaluate risk factors.

DESIGN

Population-based univariate and multivariate analysis of blood pressure in 1124 Alaska Natives over 20 years of age.

RESULTS

The sample had mean: age 45 years, body mass index 27, systolic pressure 123 mmHg and diastolic pressure 73 mmHg. The age-adjusted rate of hypertension > or = 160/95 mmHg was 9.1% and 6.8% among Athabascan Indians and Yup'ik Eskimos, respectively. After controlling for age and sex there was significantly more hypertension among Athabascan Indians (OR = 1.53, CI = 1.07-2.2, p = 0.019) compared to Yup'ik Eskimos. Race was significantly associated with blood pressure > or = 140/90 when controlled for age and overweight (p = 0.01, OR = 0.78, CI = 0.69-0.95). The presence of hypertension was significantly associated with the following: intake of non-indigenous food (p = 0.01); mechanized activities (p = 0.01); and glucose intolerance in both women (p = 0.043) and men (p = 0.001). Multiple regression analysis revealed age (OR = 1.06, CI = 1.05-1.08) and overweight in both men (OR = 3.02, CI = 1.85-4.93) and women (OR = 2.76, CI = 1.81-4.19) to be significantly associated with BP > or = 140/90.

CONCLUSION

Hypertension is no longer rare in Alaska Natives and is associated with overweight, non-indigenous diet, mechanized activities, and glucose intolerance.

Risk factors for coronary heart disease among Navajo Indians: findings from the Navajo Health and Nutrition Survey

Coronary heart disease was uncommon among the Navajo in the past, but appears to have increased substantially over the last few decades. The 1991-1992 Navajo Health and Nutrition Survey, which included interviews and examinations of 303 men and 485 women between the ages of 20 and 91 y, is the first population-based examination of coronary heart disease risk factors in this tribe. Coronary heart disease risk characteristics were common, particularly overweight (men, 35%; women, 62%), hypertension (men, 23%; women, 14%) and diabetes mellitus (men, 17%; women, 25%). Among 20- to 39-y-olds, a large proportion of men reported that they currently smoked cigarettes (23%); use of chewing tobacco or snuff was also prevalent among these 20- to 39-y-old men (37%) and women (31%). Although serum concentrations of total cholesterol were fairly comparable to those seen in the general U.S. population, fasting serum triglyceride concentrations were high (median: men, 132 mg/dL; women, 137 mg/dL), and concentrations of HDL cholesterol were low, particularly among women (median: men, 42 mg/dL; women, 44 mg/dL). Body mass index was associated with levels of most risk factors, and, independently of the level of overweight, a truncal pattern of body fat was related to adverse lipid levels among men. A large proportion of men (20%) and women (30%) reported not having participated in physical activity during the preceding month. Lessons learned from past intervention activities among the Navajo, particularly those for diabetes, may be useful in managing these risk factors to reduce the future burden of coronary heart disease.

Weight, body image, and weight control practices of Navajo Indians: findings from the Navajo Health and Nutrition Survey

Historically, the Navajo exhibited a low prevalence of overweight, but a number of small studies over the past few decades indicate that the prevalence is increasing. In the population-based Navajo Health and Nutrition Survey conducted in 1991-92, overweight was defined as a body mass index (BMI, kg/m2) at or above the 85th percentile (BMI > 27.8 for men, > 27.3 for women) of the Second National Health and Nutrition Examination Survey. One third of men age 20 and 39 and one half of men age 40 and 59, but fewer than 10% of men age 60 and older were overweight. Two thirds or more of women in all age groups were overweight. Nineteen percent of the participants underestimated their weight status (underweight, appropriate, overweight) relative to their BMI category and 17% overestimated their weight status. Women overestimated their weight status more often than men (P < 0.05), and participants age 20-39 overestimated their weight status more often than older participants (P < 0.001). Men and women age 60 and older preferred heavier body shape models as ideals of health more often than younger participants (P < 0.001). Nearly half of the participants, regardless of their weight status, reported that they were trying to lose weight; most reported using diet and exercise. Because overweight is an important risk factor for many chronic diseases, including diabetes mellitus, cardiovascular disease and cancer, primary prevention of overweight and weight management for adults are recommended to prevent an increase in the burden of chronic disease among the Navajo.

Prevalence of hypertension among Navajo Indians: findings from the Navajo Health and Nutrition Survey

Hypertension and other chronic diseases are becoming increasingly important health problems for many Native American people, including the Navajo. A community-based survey that included three standardized measurements of blood pressures, was conducted during 1991-92 on the Navajo Reservation. Among the 780 adults examined, the overall age-standardized prevalence of hypertension, defined as an elevated systolic (> or = 140 mm Hg) or diastolic (> or = 90 mm Hg) blood pressure, or possession of prescription antihypertensive medications, was 19% (24% among men and 15% among women). The prevalence of hypertension increased with age and relative weight, and among men, was associated with diabetes mellitus. Among women, hypertension was associated with a central distribution of body fat, cigarette smoking, self-reported diabetes mellitus and impaired glucose tolerance. Although only 50% of the persons found to have elevated blood pressure at the examination reported they had been previously told that they had hypertension, persons who had been previously diagnosed with hypertension had a slightly higher rate (approximately 60%) of blood pressure control than that seen in the general U.S. population. On the basis of these results, the prevalence of hypertension among the Navajo appears to have substantially increased since the 1930s. Improved prevention and management of hypertension, especially for overweight and diabetic individuals, may reduce morbidity and mortality from cardiovascular and renal disease.

An epidemiologic review of dietary intake studies among American Indians and Alaska Natives: implications for heart disease and cancer risk

PURPOSE

Dietary factors play an important role in the occurrence of heart disease and cancer. While American Indians and Alaska Natives (AIANs) have unique heart disease and cancer mortality profiles, little is known about the effect of diet on heart disease and cancer risk in these populations. This paper reviews existing nutritional intake data from adult AIANs, and considers the potential impact of diet on heart disease and cancer in these communities.

METHODS

A review of the literature was conducted using the Medline database system and other reference materials. Studies documenting nutrient intakes only were included in this review. Studies were limited to those among healthy, non-pregnant adults.

RESULTS

A total of twelve reports from 1959 to 1996 were found. Sample sizes for the studies ranged from 20 to 575 subjects. Most studies were done among women, and a variety of nutritional assessment techniques (24 hour recall, food frequency questionnaire, multiple-day food record) were used. Most studies also had limited nutrient intake data, especially for dietary fiber and vitamin E. The majority of studies reported moderately high intakes of fat and saturated fat, and low intakes of polyunsaturated fat and fiber.

CONCLUSIONS

Based on the limited data, diet may play an important role in the heterogeneity of heart disease and cancer mortality in AIAN communities. More research is needed to assess the impact of diet on heart disease and cancer risk, including more longitudinal data, and data to assess the validity and reliability of traditional methods of dietary assessment.

Urinary findings and renal function in adult Navajo Indians and associations with type 2 diabetes

We screened a sample of adult Navajo Indians for signs of renal disease that might underlie their increasing rates of renal failure. Nondiabetics had modest rates of hypertension, which was more common in males and increased with age. Microscopic hematuria was very common, and only a fraction was associated with progressive nephropathy. Microalbuminuria, mostly undetected by routine dipstick, was present in 14.6% of subjects; overt albuminuria was present in 2%. Increasing albuminuria was related to renal insufficiency, which was more common in males. Hypertension was associated with greater then threefold increases in both albuminuria and renal insufficiency. Cardiovascular disease was uncommon and had no discernible relationship to albuminuria. Most diabetic patients (58.4%) had hypertension, with equal rates for males and females. Fully half of all diabetic patients had unsatisfactory blood pressure levels at screening. Rates and patterns of hematuria were like those of nondiabetics. Microalbuminuria was present in 36.1% and overt albuminuria in 17.9%, four and eight times the rates in matched nondiabetics, respectively; these differences persisted after controlling for blood pressure. Renal insufficiency was associated with progressive albuminuria and was present in 10.6%, with equal rates in males and females. Hypertension, albuminuria, and renal insufficiency, but not hematuria, increased with increasing diabetes duration. Hypertension was associated with a twofold increase in albuminuria, a threefold increase in overt albuminuria, and an eightfold increase in renal insufficiency. Cardiovascular disease had no detectable association with microalbuminuria, but had a strong relationship to overt albuminuria. The high rates of hematuria are not well explained. It probably has nonrenal as well as renal origins, the latter including mesangial proliferative glomerulonephritis. The impressive rates of albuminuria among diabetic patients mark a large reservoir of renal disease and fore-shadow even larger burdens of end-stage renal disease and cardiovascular disease in the near future. Improved detection and treatment of hypertension is needed to slow the progression of renal disease in nondiabetics and diabetics, together with screening and treatment protocols for albuminuric diabetic patients. Prevention of albuminuria probably involves population-based modification of blood pressure and metabolic profiles.

Hypertension in adult American Indians. The Strong Heart Study

Hypertension is a primary risk factor for cardiovascular disease in the United States. Although cardiovascular disease is the leading cause of death among American Indians, the prevalence of hypertension, its awareness and control, and its association with other cardiovascular disease risk factors and physiological variables have not been well studied in this population. The Strong Heart Study is a longitudinal study of cardiovascular disease and its risk factors in American Indians. Participants (2703 women and 1846 men) were members of 13 tribes in central Arizona, southwestern Oklahoma, and regions of South and North Dakota. At least 1500 individuals between 45 and 74 years of age participated from each center in a baseline clinical examination conducted between July 1989 and January 1992. The examination consisted of a personal interview and physical examination that included an oral glucose tolerance test and three consecutive blood pressure measurements. This study reports data from the baseline examination on the prevalence of hypertension and correlates of blood pressure. Results indicated that despite the high frequency of diabetes and obesity, prevalence rates of hypertension in Arizona and Oklahoma were similar to those in the US population in the Third National Health and Nutrition Examination Survey (NHANES III), and rates among South/North Dakota participants were significantly lower (P < .0001). Blood pressure was higher in individuals with diabetes (P < .0001) and was significantly correlated with age (P < .0001) and albuminuria (P < .0001) but only weakly related to obesity. There was no independent relation between blood pressure and insulin. Blood pressure seems to be less affected by obesity and hyperinsulinemia in American Indians compared with other populations. Nevertheless, hypertension should be aggressively treated and controlled in American Indians because it is a known precursor to morbidity and mortality associated with diabetes and cardiovascular disease.

Inaccuracy of self-reported weights and heights among American Indian adolescents

To determine the accuracy of self-reported weights and heights and of relative weight status in a sample of American Indian adolescents, a survey was conducted in middle and high schools on or near three Indian reservations-Navajo, Choctaw, and Blackfeet. Self-reported weights and heights were compared with measured weights and heights. Participants were 12 through 19 years old. (N = 806, 47.4% male). Overall, both boys and girls underreported weight (mean difference = self-reported - measured mean values)(-3.4 +/- 13.1 and -4.6 +/- 13.0 lb, respectively) and overreported height (0.6 +/- 2.1 and 0.2 +/- 2.6 in, respectively) However, underweight boys and girls overreported weight (normal: -1.6 +/- 7.9 and -1.4 +/- 6.3; overweight: -7.5 +/- 17.9 and -11.6 +/- 19.0 lb, respectively). Although correlations between measured and reported weight, height, and body mass index (BMI) were high, the sensitivity of relative weight categories based on BMI using self-reported weight and height compared with measured weight and height was poor: 66.7% for underweight (BMI < 15th percentile, based on a national reference population), 88.9% for normal weight, and 73.6% for overweight (> 85th percentile). These results call into question the accuracy of self-reported weight and height measurements among American Indian youth and are similar to findings among non-American Indian adolescents. Therefore, their use in prevalence studies should be avoided, and they should be used cautiously in other types of epidemiologic studies.

Interaction of acetaldehyde with plasma proteins of the renin-angiotensin system

Chronic alcohol abuse may lead to hypertension by stimulating the activity of the renin angiotensin system (RAS). While there are reports on the alcohol associated increase of angiotensin II in rats and increases of plasma renin activity in rats and human alcoholics, the exact mechanisms of stimulation of the RAS activity is not clear. This study provides evidence for a biochemical interaction of acetaldehyde, the primary oxidative metabolite of ethanol, upon bilaterally nephrectomized (NEPEX) rat plasma that contains significant quantities of angiotensinogen and lacks active renin. Rat plasma served as the source of renin in this study. Preincubation of NEPEX plasma with 0.2 M acetaldehyde at 4 degrees C for 2 h resulted in a 21% increase in the angiotensin I (A I) formation by the rat plasma renin and 27% increase in the A I formation by the trypsinized rat plasma renin. When the rat plasma which contains modest quantities of endogenous angiotensinogen in addition to renin was preincubated with 0.2 M acetaldehyde at 4 degrees C for 2 h, the rate of A I formation was increased by 10%. Equivalent amounts of ethanol did not modify the rate of A I generation when added to NEPEX plasma or rat plasma. These results suggest the possibility of a biochemical interaction of acetaldehyde with the renin substrate which may enhance the activity of the RAS cascade, thereby contributing to hypertension in chronic alcoholics.

Blood pressure comparison in a selected Native American and white population

This study compared the frequency of blood pressure elevation in a selected Native American and white population. Three hundred individuals participated: 87 Native Americans, 210 whites, and 3 others. Data were gathered using a questionnaire that addressed residence, sex, age, race, occupation, height, smoking, alcohol use, tea/coffee consumption, medications, and past or present illness. Weight and blood pressure were measured by the researchers at the time of data collection. The sample mean for systolic blood pressure (SBP) was 124 mm Hg (SD 14.78) and diastolic blood pressure (DBP) was 77 mm Hg (SD 10.13). One-way analysis of variance showed age groups and sex to affect blood pressure significantly (P = 0.0001). Stepwise multiple regression indicated weight significantly predicted blood pressure (SBP multiple R = 0.39, P = 0.001; DBP multiple R = 0.43, P = 0.00001). The interaction of age, sex, tobacco, alcohol, and caffeine influenced SBP and DBP. Obviously, these findings have limited generalizeability due to the sampling frame used in this study.

Prevalence and correlates of hypertension in a subarctic Indian population

BACKGROUND

In a cross-sectional survey of 704 Cree and Ojibwa Indians ages 20-64 in six northern Canadian communities, blood pressure was measured along with various anthropometric, dietary, biochemical, sociodemographic, and lifestyle data.

METHODS

Two readings of systolic (SBP) and diastolic (DBP) pressures were obtained using a mercury sphygmomanometer in accordance with WHO protocol. In analyses where blood pressure (BP) was a continuous variable, the means of the two readings were used. Where "hypertension" as a dichotomous variable was used, a "normal" subject was one with no past history of known physician-treated hypertension and who currently had SBP less than or equal to 140 and DBP less than or equal to 90 mm Hg. All others were classified as "hypertensives."

RESULTS

Based on these criteria, the adjusted prevalence of hypertension in the sample was 27%, with an increased frequency among males and those in the older age group. Compared with data from the Canada Health Survey, the mean SBP among the Indians exceeded that of Canadians in the younger age groups but was lower beyond age 45. For DBP, Indians had higher mean levels than Canadians consistently across all age groups and in both sexes. On univariate comparisons, significantly higher BP levels were found among men, the old, those with little education, nondrinkers, the physically inactive, the obese, and the diabetic. Hypertensives also differed from nonhypertensives in terms of total cholesterol, triglycerides, high-density lipoprotein cholesterol/total cholesterol ratio, various indices of obesity and fat patterning, and fasting glucose levels. In a multiple logistic regression model, significant predictors of hypertensive status included male sex, age, body mass index, total cholesterol, unemployed and single marital status, and positive family history of hypertension.

High incidence of sudden infant death syndrome among northern Indians and Alaska natives compared with southwestern Indians: possible role of smoking

Epidemiologic studies of sudden infant death syndrome (SIDS) in the United States have found a particularly high incidence among American Indians and Alaska Natives compared with whites. This report shows that there is a remarkable difference in the incidence of SIDS between Northern Indians and Southwestern Indians. From 1984 through 1986, the incidence of SIDS was 4.6 per 1,000 live births among Indians and Alaska Natives in the Northern region of the United States, while the incidence among Southwestern Indians was 1.4 per 1,000 live births (risk ratio = 3.4; 95 percent confidence interval = 2.4-4.8). Among whites living in the same regions, the incidence of SIDS was 2.1 and 1.6 per 1,000 live births, respectively. The incidence among Native Americans in the Northern region was high in all five Indian Health Service Areas. Differences in socioeconomic status, maternal age, birth weight, and prenatal care did not appear to explain the higher incidence of SIDS among Northern Indians compared with Southwestern Indians. However, the prevalence of maternal cigarette smoking during pregnancy is exceptionally high among Northern Indians and Alaska Natives, while it is low among Southwestern Indians. This difference in smoking habits may explain, at least in part, the excess risk of SIDS among Indians in the Northern region. This report points to the need for effective smoking cessation programs for Native Americans, targeting in particular women of reproductive age.

The major respiratory diseases of American Indians

The most prominent respiratory diseases of American Indian adults are pneumonia, cancer of the lung, chronic obstructive pulmonary disease (COPD), and tuberculosis. Mortality and hospitalization rates of these diseases were compared with those for the rest of the U.S. population and between Indian groups in the various Indian Health Service Areas. Pneumonia and influenza constitute the sixth leading cause of death among Indians and the fifth leading cause of death among the U.S. All Races population. Chronic obstructive pulmonary disease is the fourth leading cause of death among U.S. All Races, but only the tenth leading cause of death among Indians. Pneumonia and tuberculosis are more significant causes of death and disability for Indians than are COPD and cancer of the lung. The explanation for these differences in mortality rates between Indians and the general population are not known. Respiratory system diseases are responsible for 10.6% of Indian hospitalizations. The most frequent is pneumonia, which accounts for approximately 4% of all Indian hospitalizations. Differences in respiratory diseases between Indian groups are sometimes striking, with a sharp increase in mortality and hospitalization in the Areas across the northern border of the lower 48 states. There is also a much higher prevalence of cigarette smoking in those same Areas.

Injury mortality in American Indian, Hispanic, and non-Hispanic white children in New Mexico, 1958-1982

Childhood fatalities from injuries are a serious public health problem in New Mexico, a state which ranks second in the nation in injury-related mortality rates. To determine the extent of injury mortality in children in this state, and to examine time trends and differences in mortality rates in New Mexico's American Indian, Hispanic, and non-Hispanic white children aged 0-14 years, we analyzed vital records collected from 1958 to 1982. American Indian children experienced the highest mortality rates from all external causes combined. Among all three major ethnic groups, children aged 0-4 years were at the highest risk for injury fatalities. Unintentional injuries accounted for 85% of all injury-related deaths. Motor vehicle crashes and drowning were the first and second leading causes of death in all three groups, while other important causes of death included fire, choking on food or other objects, poisoning, and homicide. Although the fatality rates on most types of injuries decreased over the 25-year period, childhood fatality rates for motor vehicle crashes and homicide increased in each ethnic group. Despite the overall decrease in injury mortality rates in New Mexican children, the rates are excessively high compared to other states, especially in American Indian children.

More frequent diagnosis of acute myocardial infarction among Navajo Indians

In an earlier study, we failed to confirm a clinical impression that the incidence of acute myocardial infarction (AMI) was increasing in Navajo men. Extending our data collection an additional three years, through 1986, we observed that the attack rate in men more than doubled and there was a gradual increase among women. Most Navajos who sustain AMI are hypertensive (51 per cent), diabetic (50 per cent) or both (31 per cent), but few smoke cigarettes.

Mortality from lung cancer and chronic obstructive pulmonary disease in New Mexico, 1958-82

We examined mortality from lung cancer and from chronic obstructive pulmonary disease in Hispanic White, Other White, and Native American residents of New Mexico during the period 1958-82. Age-specific mortality was calculated by combining death certificate data with population estimates based on the 1960, 1970, and 1980 censuses that were adjusted for inconsistencies in the designation of race and ethnicity. In Other Whites, age-adjusted mortality rates from lung cancer and from chronic obstructive pulmonary disease increased progressively in males and females. Mortality rates for both diseases also increased in Hispanics during the study period, but the most recent rates for Hispanics were well below those for Other Whites. Age-specific mortality rates for lung cancer declined for more recently born Hispanic women at older ages. In Native Americans, rates for both diseases were low throughout the study period and did not show consistent temporal trends.

Ischemic heart disease mortality in Hispanics, American Indians, and non-Hispanic whites in New Mexico, 1958-1982

To describe trends in mortality from ischemic heart disease in New Mexico's Hispanic, American Indian, and non-Hispanic white populations, we used vital records data collected from 1958 through 1982. We calculated age-adjusted and age-specific mortality rates for ischemic heart disease for each of the state's principal ethnic groups. Death certificate data were used in combination with population estimates based on the censuses of 1960, 1970, and 1980. Age-adjusted mortality rates for ischemic heart disease among Hispanics, American Indians, and non-Hispanic white men were consistent with nationwide patterns of rising mortality rates during the 1960s followed by declining rates. Mortality rates from ischemic heart disease in all three ethnic groups in New Mexico were lower than national rates for whites. Rates for Hispanics in New Mexico were lower than for non-Hispanic whites; rates for American Indians were the lowest among the three groups. These data support previous observations that Hispanics and American Indians in the Southwest are at decreased risk for mortality from ischemic heart disease in comparison with U.S. whites.

Oral health effects of smokeless tobacco use in Navajo Indian adolescents

Recent reports have suggested that the use of smokeless tobacco is increasing in adolescents, and is particularly high in Native Americans, causing concern about possible effects on oral health. In this study, 226 Navajo Indians, aged 14-19, were interviewed regarding their use of smokeless tobacco (ST), cigarettes, and alcohol. Midbuccal and mesiobuccal sites on all fully erupted permanent teeth (excluding third molars) were examined for the presence of gingival bleeding, gingival recession, calculus, and loss of periodontal attachment. The oral mucosa was examined for evidence of leukoplakia. 64.2% (145) of the subjects (75.4% of the boys and 49.0% of the girls) were users of ST. Of these, over 95% used snuff alone or in combination with chewing tobacco. 55.9% used ST one or more days per week. 52.2% consumed alcohol, usually beer or wine, and 54.0% smoked cigarettes. 25.5% (37) of the users and 3.7% (3) of the non-users had leukoplakia. The duration (in years) and frequency of ST use (days per week) were highly significant risk factors associated with leukoplakia. However, the concomitant use of alcohol or cigarettes did not appear to increase the prevalence of these lesions. No consistent relationship was observed between the use of ST and gingival bleeding, calculus, gingival recession, or attachment loss, either when comparing users to non-users or when comparing the segment where the tobacco quid was habitually placed to a within-subject control segment. In view of these results, there is little doubt that smokeless tobacco is significantly related to the etiology of leukoplakia. As some evidence exists that smokeless tobacco use is a significant risk factor associated with oral carcinoma, intervention programs to discourage the use of smokeless tobacco by adolescents should be a public health priority.

The prevalence of hypertension among elderly Navajos: a test of the acculturative stress hypothesis

This is a study of the prevalence of hypertension among a sample of Navajo Indians 65 years of age and above. It is not clear whether prevalence has increased over the past generation in this age group. When men and women are compared, conventional measures of "acculturation" are related to hypertension among women but not among men. The differences between men and women seem most probably related to differences in the situation of men and women within both Navajo and Anglo-American society. Several alternative explanations are discussed as well.

Elevations in plasma angiotensin II with prolonged ethanol treatment in rats

Chronic alcohol consumption frequently leads to hypertension in humans. While previous reports have implicated the renin-angiotensin system as a potential mediator of this effect, plasma angiotensin II (AII) levels were either not measured or yielded negative results. The present investigation noted significant elevations in circulating AII in rats intubated daily with ethanol (4 g/kg) for 50 days. Animals administered ethanol only once evidenced AII concentrations equivalent with water intubated controls. Radioligand binding assay data indicated no differences in the number or affinity of Sar1,Ile8-AII binding sites in the thalamus, septum-anterior ventral third ventrical region or adrenal gland comparing those groups chronically treated with ethanol to water intubated controls. These results may support a role for the vasoconstrictive hormone AII in the etiology of alcohol-induced hypertension.

Acute myocardial infarction among Navajo Indians, 1976-83

We found that from 1976 through 1983 the incidence of acute myocardial infarction (AMI) diagnosed among Navajo Indians remained low (0.5 per 1,000 persons age 30 years or more), although the incidence in women appears to be climbing. Navajo AMI patients are more likely to be hypertensive and diabetic than age- and sex-matched patients with gallbladder disease. Twenty-four per cent die within one month of AMI.

Hypertension prevalence among Penobscot Indians of Indian Island, Maine

Prevalence of hypertension, measured on a random sample of Penobscot Indian adults on reservation in Maine, was 23 per cent. Only 50 per cent of the hypertensive Penobscots were aware of their condition. Among those treated with antihypertensive medications, 56 per cent were controlled. When compared to a statewide sample of Maine adults, the prevalence of hypertension among Penobscots was similar but awareness was significantly lower.

Alcohol consumption and cardiovascular risk factors

This chapter reviews epidemiologic evidence relating alcohol consumption to the cardiovascular risk factors of high-density lipoprotein (HDL)-cholesterol and blood pressure. Alcohol consumption shows a linear dose-response relationship with HDL-cholesterol that is independent of other known determinants of HDL-cholesterol. The effect of alcohol on HDL-cholesterol appears to be reversible. The relationship of alcohol consumption to HDL-cholesterol subfractions and to the HDL apoproteins is not clear. Alcohol consumption also shows a linear dose-response relationship with blood pressure. Although the association is consistent, the estimated effect of alcohol consumption on blood pressure is small. This effect of alcohol may also be reversible. No biological mechanisms have been established for these associations. Some of the effect of alcohol on the risk of coronary heart disease may be explained by the effects of alcohol on these risk factors. It remains to be determined if alcohol also exerts an effect that is independent of these risk factors.

Uranium mining and lung cancer in Navajo men

We performed a population-based case-control study to examine the association between uranium mining and lung cancer in Navajo men, a predominantly nonsmoking population. The 32 cases included all those occurring among Navajo men between 1969 and 1982, as ascertained by the New Mexico Tumor Registry. For each case in a Navajo man, two controls with nonrespiratory cancer were selected. Of the 32 Navajo patients, 72 per cent had been employed as uranium miners, whereas no controls had documented experience in this industry. The lower 95 per cent confidence limit for the relative risk of lung cancer associated with uranium mining was 14.4. Information on cigarette smoking was available for 21 of the 23 affected uranium miners; eight were nonsmokers and median consumption by the remainder was one to three cigarettes daily. These results demonstrate that in a rural nonsmoking population most of the lung cancer may be attributable to one hazardous occupation.

Blood pressure in a community at high altitude (3000m) at Pooh (North India)

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Blood pressure and alcohol intake in heart patients

The association between alcohol consumption and blood pressure has been studied in 2025 male and 282 female patients undergoing diagnostic coronary angiography. The increase in amount of alcohol consumed correlated with higher systolic and diastolic blood pressure; this effect was especially pronounced in men over 50 years of age. The association was less marked in male patients under 50 years old, in women, and in patients on antihypertensive medication. Readings in the range of definitive hypertension were more prevalent among older patients consuming six or more drinks daily than in abstainers of the same age group.

Blood pressure of urban Native American school children

In 307 Native American (NA), 1784 black (B), and 7777 white (W) children in grades 1, 2, and 3 in Minneapolis schools (99% overall response rate), blood pressure (BP) was measured supine in the right arm after 5 minutes' rest by trained technicians using a random zero BP device. In addition, height, weight, pulse rate, and triceps skinfold thickness were measured. Among children aged 6 through 9 years, NA children had slightly higher systolic BP (SBP) than B or W children overall (mean SBP: NA 106, B 104, W 105 mm Hg) and for nearly all age sex groups. In contrast, Phase 4 and 5 diastolic BP (DBP) were consistently lower in NA children ( mean DBP4: NA 64, B 69, W 67 mm Hg); NA children also had lower pulse rates, greater pulse pressures, similar or slightly lower mean BP, similar height, greater weight, body mass index, and triceps skinfold. Multiple regression analyses revealed that the slightly higher SBP in NA children was explained almost entirely by greater ponderosity. However, the lower DBP could not be explained statistically by any of the variables measured.