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T K Welty

Publications and source records attributed to T K Welty.

At least 19 recordsLinked to original sources
PubMed1995

Coronary heart disease prevalence and its relation to risk factors in American Indians. The Strong Heart Study.

Although coronary heart disease (CHD) is currently the leading cause of death among American Indians, information on the prevalence of CHD and its association with known cardiovascular risk factors is limited. The Strong Heart Study was initiated in 1988 to quantify cardiovascular disease and its risk factors among three geographically diverse groups of American Indians. Members of 13 Indian communities in Arizona, Oklahoma, and South and North Dakota between 45 and 74 years of age underwent a physical examination that included medical history; an electrocardiogram; anthropometric and blood pressure measurements; an oral glucose tolerance test; and measurements of fasting plasma lipoproteins, fibrinogen, insulin, hemoglobin A1c, and urinary albumin. Prevalence rates of definite myocardial infarction and definite CHD were higher in men than in women at all three centers (p < 0.0001) and higher in those with diabetes mellitus (p = 0.002 in men and p = 0.0003 in women). Diabetes was associated with relatively higher prevalence rates of myocardial infarction (diabetic:nondiabetic prevalence ratio = 3.8 vs. 1.9) and CHD (prevalence ratio = 4.6 vs. 1.8) in women than in men. Prevalence rates of heart disease were lowest in the communities in Arizona; prevalence rates were similar in Oklahoma and South Dakota/North Dakota and were two- to threefold higher than those in Arizona. By logistic regression, prevalent CHD among American Indians was significantly and independently related to age, diabetes, hypertension, albuminuria, percentage of body fat, smoking, high concentrations of plasma insulin, and low concentrations of high density lipoprotein cholesterol. In contrast to reports from other non-Indian populations, diabetes was the strongest risk factor. The lower prevalence of CHD among Indians in Arizona is distinctive in view of their higher rates of diabetes, obesity, hypertension, and albuminuria, but it may be partly related to their low frequency of smoking and their low concentrations of total and low density lipoprotein cholesterol. These findings from the initial Strong Heart Study examination emphasize the importance of diabetes and its associated variables as risk factors for CHD in Native American populations.

Aged↗
PubMed1995

Cardiovascular disease risk factors among American Indians. The Strong Heart Study.

The Strong Heart Study, a study of cardiovascular disease among American Indians, was conducted to determine cardiovascular disease rates and the prevalence of risk factors among members of 13 tribal groups in South Dakota/North Dakota (SD/ND), southeastern Oklahoma, and Arizona. From 1989 to 1992, 4,549 tribal members aged 45-74 years (62% of eligible participants) were surveyed and examined for cardiovascular disease and its risk factors. Mean total cholesterol concentrations were over 20 mg/dl lower among the men and 27 mg/dl lower among the women than national mean levels for the same age groups. Cholesterol levels varied by tribal group; Arizona Indians had mean levels more than 20 mg/dl lower than those of SD/ND Indians. The prevalence of hypercholesterolemia was almost twice as high among SD/ND Indians as among Arizona Indians, but the rates for all three groups were much lower than total US rates (all races). Mean levels of high density lipoprotein cholesterol were lower among Indian men and women than in the US population as a whole. The prevalence of hypertension among Arizona and Oklahoma Indians was higher than that for the entire United States. SD/ND Indians had significantly lower mean blood pressures and prevalence rates of hypertension than Oklahoma and Arizona Indians and the United States as a whole. The prevalence of cigarette smoking was higher for all Indian groups except Arizona women in comparison with US rates. Smoking rates were highest in SD/ND and lowest in Arizona. Indian smokers smoked fewer cigarettes per day than the average US smoker. Arizona Indians had the highest prevalence of diabetes mellitus; over 60% of those participants were diabetic. In Oklahoma and SD/ND, one third of the men and over 40% of the women were diabetic. In addition, 13-20% of the participants had impaired glucose tolerance. Proteinuria was also a common problem; almost half of the Arizona Indians had micro- or macroalbuminuria, and 20% of Oklahoma and SD/ND Indians had significant proteinuria. The prevalence of obesity was high in all three groups, with Arizona Indians having the highest rates and the highest mean body mass indices. The prevalence of current alcohol use was lower among Indians than in the nation as a whole, but binge drinking was common among those who used alcohol. These results indicate that cardiovascular disease risk factors vary significantly among tribal groups. Prevention programs tailored toward decreasing the prevalence of risk factors are recommended for long-term reduction of cardiovascular disease rates in American Indian communities.

Aged↗
PubMed1994

Type II diabetes and cognitive function. A population-based study of Native Americans.

OBJECTIVE: To explore the relationship between type II diabetes and cognitive function in older Native Americans and to assess the effects of other selected risk factors for cognitive dysfunction on this relationship. RESEARCH DESIGN AND METHODS: Cognitive function was assessed in 80 diabetic and 81 nondiabetic Native Americans who were 45-76 years of age in a cross-sectional population-based sub-study of the Strong Heart Study. Thirteen cognitive function tests were administered during a personal interview. Information about six other risk factors for cognitive dysfunction, including depressive symptoms, physical function, alcoholism, current alcohol use, hypertension, and myocardial infarction, was ascertained from interviews and from abstraction of medical records. RESULTS: Diabetes was associated with impairment on only two tests of cognitive function: verbal fluency (P = 0.004) and similarities (P = 0.010). Depressive symptoms were related to verbal fluency (P = 0.004), but did not explain the diabetes-related difference in performance. The effects of hypertension, depressive symptoms, and current alcohol use explained the diabetes-related performance difference on similarities. Cognitive function was not related to metabolic control (HbA1c level). CONCLUSIONS: We found little evidence that type II diabetes in this population of Native Americans is associated with decrement in cognitive function. Some of the cognitive impairment previously attributed to diabetes may be related, at least in part, to the influence of other risk factors. This should be considered in the design of future studies in other populations.

Aged↗
PubMed1994

Cultural factors associated with health-risk behavior among the Cheyenne River Sioux.

A field study was conducted to identify cultural factors--values, beliefs, and related characteristics--associated with health-risk behavior among adult members of the Cheyenne River Sioux Tribe. The Cultural Values Survey (CVS), an instrument for measuring cultural values and related characteristics, was developed and pilot tested in the study population. This instrument, along with the Health Risk Appraisal (HRA) (an instrument developed by the Centers for Disease Control to quantify major health-related behaviors), was administered to a random sample of 429 adults in the study community. Significant differences between females and males for both cultural characteristics and health-risk behaviors were found. Females had significantly higher HRA-calculated Health Index values than males, reflecting overall healthier behaviors. Females who scored higher on cultural factors consistent with more traditional Lakota Indian lifestyles (e.g., degree of Indian blood, Lakota language spoken in the home, traditional Lakota beliefs) had higher HRA Health Index values than females scoring lower in these characteristics. Males who scored higher in factors related to self-determination (e.g., hard work, personal control, industriousness, individual action) had higher Health Index values than those who scored lower in these areas. Further testing of the CVS instrument, as well as further research from both epidemiologic and social science perspectives is essential to elucidate the nature of the relationship between cultural factors and health-related behavior.

Adolescent↗
PubMed1994

On consumption.

Explore the source record for details and available documents.

AIDS-Related Opportunistic Infections↗
PubMed1993

Cardiovascular disease among American Indians and Alaska Natives.

OBJECTIVE: To compare the regional differences in cardiovascular disease in AI/AN with the U.S. general population and determine the parity gap and preventable proportion of cardiovascular mortality. RESEARCH DESIGN AND METHODS: Age-adjusted cardiovascular disease mortality rates for 1981-1983 and hospital discharge rates for 1982-1984 reported by the IHS were compared with U.S. data for 1982 and 1983, respectively. RESULTS: Rates of ischemic heart disease and atherosclerosis were found to be generally low among AI/AN although those in the 25- to 44-yr age-group have higher death rates from cardiovascular disease than in the U.S. population. Although the mortality rate from cardiovascular disease in AI/AN is 19% lower than the rate for the general U.S. population, the parity gap in individual regions of the U.S. ranges from favorable to extremely unfavorable. There were also wide variations in the preventable gap theoretically possible by reduction of the three major risk factors. CONCLUSIONS: Changing nutrition and exercise patterns and the increasing prevalence of diabetes in many Indian tribes may have adverse effects in the future, possibly increasing the prevalence of heart disease. Regional differences in the prevalence of some major cardiovascular risk factors (smoking, hypertension, hypercholesterolemia, and diabetes) are the probable explanation for these differences in cardiovascular morbidity and mortality rates. Prevention and treatment of these risk factors will have the greatest impact in attempts to reduce cardiovascular disease among AI/AN. In addition, moderation in the use of alcohol, or abstinence, may prevent sudden deaths resulting from acute intoxication.

Adult↗
PubMed1993

Hypertension and blood pressure awareness among American Indians of the northern plains.

This study compared self-reported and measured blood pressure among American Indians of the northern plains. In 1986, a group of American Indians from the northern plains was administered the Centers for Disease Control Behavioral Risk Factor Survey (which included a question about previous blood pressure measurements) and a health risk appraisal (which included blood pressure measurement). Approximately 18% of the respondents reported being told by a doctor, nurse, or other health professional that they had high blood pressure, and 11% actually had measured blood pressures of at least 140/90 mm Hg. Overall, only 50% of hypertensive participants correctly identified themselves as hypertensive (sensitivity); specificity was 92%, predictive value positive was 43%, predictive value negative was 94%, and efficiency (the proportion of individuals who correctly classified their blood pressure status as high or normal) was 87%. These findings agree with similar studies of hypertension awareness, and they indicate that lack of this awareness remains a significant problem in the fight against cardiovascular diseases and premature death among American Indians.

Adolescent↗
PubMed1992

Risk factors for coronary heart disease in diabetic and nondiabetic Native Americans. The Strong Heart Study.

The Strong Heart Study is a study of cardiovascular disease and its risk factors among diabetic and nondiabetic Native Americans. The study includes 12 tribes in Arizona, Oklahoma, and North and South Dakota. Phase I, initiated in October 1988, included a mortality survey to determine CVD death rates in individuals 35-74 yr old between 1984 and 1988, and a medical record review to determine rates of myocardial infarction and stroke for individuals ages 45-74 during the same time. In addition, a physical examination was performed on persons 45-74 yr old to measure the prevalence of cardiovascular and peripheral vascular diseases and known and suspected risk factors. In Phase II, CVD mortality and morbidity rates will be determined in the examined cohort by surveillance. CVD risk factors, changes in risk factors over time, and the relationship between risk factors and CVD incidence will be assessed longitudinally. This study provides data on the relative importance of cardiovascular risk factors in nondiabetic and diabetic Native Americans and will provide insight into possible variations in the quantitative or qualitative importance of CVD risk factors among diverse population groups.

Adult↗
PubMed1992

The benefits of isoniazid chemoprophylaxis and risk factors for tuberculosis among Oglala Sioux Indians.

In a case-control study of 92 Indian patients, 46 with active tuberculosis (cases) and 46 tuberculin reactors without the disease (control subjects), significantly more control subjects than patients had prior adequate isoniazid chemoprophylaxis. While the Indian Health Service recommends treating all tuberculin reactors with isoniazid prophylaxis, most (75%) of our tuberculosis (TB) cases could have been prevented if the guidelines of the American Thoracic Society had been followed. Diabetes, alcohol abuse, and chronic renal failure were risk factors for active TB. Despite marked reductions in TB morbidity and mortality rates among American Indians and Alaska Natives over the past 30 years, their TB rates are still two to three times higher than overall United States and white rates. Enhanced TB control programs with an emphasis on preventive therapy for patients at risk for developing active disease, especially those with diabetes and chronic renal failure, could decrease the incidence and eventually eliminate TB among American Indians and Alaska Natives.

Adult↗
PubMed1991

Health implications of obesity in American Indians and Alaska Natives.

American Indians and Alaska Natives (AI/ANs) are experiencing an epidemic of diabetes, increasing rates of coronary artery disease and hypertension, and poor survival rates for breast cancer that are likely partially attributable to the increasing prevalence of obesity over the past generation. Obesity may also contribute to the high rates of gallstones and to adverse outcomes of pregnancy in AI/ANs. Although overall mortality was not associated with obesity in Pima Indians (except in the most obese men), the relationship of obesity to longevity in other AI/AN groups is not known. Further study of the specific health effects of obesity in various groups of AI/ANs are needed. In the meantime, community-based programs to prevent obesity and its sequelae should be implemented in all AI/AN communities.

Alaska↗
PubMed1990

The Strong Heart Study. A study of cardiovascular disease in American Indians: design and methods.

Available data indicate that cardiovascular disease has become the leading cause of death in American Indians. However, limited information is available on cardiovascular disease incidence, prevalence, and risk factors in this population. Reported cardiovascular disease rates vary greatly among groups in different geographic areas. These rates have been obtained from studies of varying sizes and different methodologies. The Strong Heart Study, which uses standardized methodology, is designed to estimate cardiovascular disease mortality and morbidity rates and the prevalence of known and suspected cardiovascular disease risk factors in American Indians. The study population consists of 12 tribes in three geographic areas: an area near Phoenix, Arizona, the southwestern area of Oklahoma, and the Aberdeen area of North and South Dakota. The study includes three components. The first is a mortality survey to estimate cardiovascular disease mortality rates for 1984-1988 among tribal members aged 35-74 years, and the second is a morbidity survey to estimate incidence of both first and first or recurrent hospitalized myocardial infarction and stroke (cerebrovascular disease) among tribal members aged 45-74 years in 1984-1988, and the third is a clinical examination of 4,500 tribal members aged 45-74 years in order to estimate the prevalence of cardiovascular disease and its associations with risk factors. Family history, diet, alcohol and tobacco consumption, physical activity, degree of acculturation, and socioeconomic status are assessed in personal interviews. The physical examination includes measurements of body fat, body circumferences, and blood pressure, an examination of the heart and lungs, an evaluation of peripheral vascular disease, and a 12-lead electrocardiogram. Laboratory measurements include fasting and postload glucose, insulin, fasting lipids, apoproteins, fibrinogen, and glycated hemoglobin. Also measured are serum and urine creatinine and urinary albumin. DNA from lymphocytes is isolated and stored for future genetic studies.

Adult↗
PubMed1990

Sudden unexplained infant deaths among American Indians and whites in North and South Dakota.

Differences in risk factors for sudden unexplained infant death (SUID) were studied among American Indian and White infants in North and South Dakota. From 1977 to 1984, the incidence of SUID was 3.9 times higher among Indians compared with Whites. Indian SUID cases appeared to die at a slightly younger age than Whites, and the association of male gender and young maternal age with SUID was weak or absent among Indians. Low maternal education and late or no prenatal care were strongly related to SUID in both races. The Indian-White risk ratio was unaltered by adjustment for birthweight and maternal age but declined to 2.5 (95% confidence intervals = 1.9, 3.4) when adjusted for maternal education and trimester prenatal care began.

Age Factors↗
PubMed1990

Hepatitis transmission among the Sioux Indians of South Dakota.

Hepatitis A continues to occur in cyclical community-wide epidemics on the Indian reservations of South Dakota. In June 1985 a population-based serosurvey for viral hepatitis involving 120 households was conducted at the Pine Ridge and Rosebud Sioux Indian reservations in South Dakota. The serosurvey was performed shortly after a large hepatitis A epidemic on the Pine Ridge reservation in 1983-84, and immediately before a large hepatitis A epidemic on the Rosebud reservation in 1985-86. The overall seroprevalence for antibodies to hepatitis A virus (anti-HAV) was 76.2 percent (Pine Ridge reservation 80.5 percent, Rosebud reservation 72.0 percent, relative risk = 1.12, 95 percent confidence interval = 1.01, 1.24). For age groups 0 to 4 years, 54.2 percent and 36.1 percent of children were seropositive at Pine Ridge and Rosebud, respectively. Seropositivity rose rapidly with age; by age 40, more than 90 percent of persons at both Pine Ridge and Rosebud were anti-HAV positive. Only 1.1 percent of persons tested were positive for hepatitis B markers. Anti-HAV seroprevalence rates in both communities are similar to rates observed in developing countries. The surprisingly high anti-HAV seroprevalence among young children at Rosebud, where clinical hepatitis A had been virtually absent in the previous seven years, indicates that high-grade silent transmission was taking place during the interepidemic period.

Adolescent↗
PubMed1990

Determinants of blood pressure in Navajo adolescents.

Hypertension is becoming more common among Navajo people, especially among young men. In a group of 580 Navajo adolescents, we looked for factors associated with variations in blood pressure level. Using our criteria, 11.1% of adolescent males and 1.6% of females had an elevated screening blood pressure. In males, blood pressure was a function of age only, and not significantly related either to obesity (body mass index) or measures of acculturation and personal adjustment. In females, blood pressure was not related to age, but was associated with body mass index. Systolic pressure in females was also associated with poor personal adjustment. Level of acculturation (by our index) had no bearing on blood pressure level in this population.

Acculturation↗
PubMed1989

Increased chromosome fragility as a consequence of blood folate levels, smoking status, and coffee consumption.

Chromosome fragility in 96 h, low-folate cultures was found to be associated with smoking status, coffee consumption, and blood folate level. The higher proportion of cells with chromosome aberrations in cigarette smokers was attributable to lower red cell folate levels in smokers compared with nonsmokers. There was a positive linear relationship between the average cups of coffee consumed per day and the proportion of cells with aberrations. This association was independent of the effects of smoking and red cell folate level. These data suggest that smoking history, coffee consumption, and red cell folate level are important considerations for the design and interpretation of fragile site studies in cancer cytogenetics.

Chromosome Aberrations↗
PubMed1989

Complete culture medium is better than low folate medium for detecting increased chromosome aberrations in smokers in 48-h lymphocyte cultures.

We compared chromosome breakage in parallel, 48-h lymphocyte cultures established from smokers and nonsmokers using minimal essential medium (MEM) and MEM without folate (MEM-FA). There was a statistically significant, higher frequency of aberrations for smokers than for nonsmokers in cells cultured in MEM, but not in those cultured in MEM-FA. Thus, these data support the recommendation of the World Health Organization (1985) that population monitoring studies for exposure assessment should not use a low folate medium.

Adult↗
PubMed1989

Acute myocardial infarction and sudden death in Sioux Indians.

While some Indian tribes have low rates of acute myocardial infarction, Northern Plains Indians, including the Sioux, have rates of morbidity and mortality from acute myocardial infarction higher than those reported for the United States population in general. In a review of diagnosed cases of acute myocardial infarction over a 3-year period in 2 hospitals serving predominantly Sioux Indians, 8% of cases were found misclassified, and 22% failed to meet rigorous diagnostic criteria, although the patients did indeed have ischemic heart disease. Patients had high frequencies of complications and risk factors and a fatality rate of 16% within a month of admission. Sudden deaths likely due to ischemic heart disease but in persons not diagnosed as having acute myocardial infarction by chart review occurred 3 times more frequently than deaths occurring within a month of clinical diagnosis.

Adult↗