PubMed Health⌕ Search

Biomedical subjects

T K Welty

Publications and source records attributed to T K Welty.

At least 55 records · Page 3Linked to original sources
PubMed1997

Relation of LDL size to the insulin resistance syndrome and coronary heart disease in American Indians. The Strong Heart Study.

Small, dense LDL has been shown to be associated with the insulin resistance syndrome and coronary heart disease (CHD). We examined the distribution of LDL size and phenotype within a population-based sample of American Indians to determine the relationships with prevalent CHD and to examine associations with hyperinsulinemia and other components of the insulin resistance syndrome. Data were available for 4505 men and women between 45 and 74 years of age who are members of 13 American Indian communities in three geographic areas. Diabetes, CHD, and CHD risk factors were assessed by standardized techniques, and LDL size was measured by gradient gel electrophoresis. LDL size was smaller in men than in women and in individuals with diabetes than in those without diabetes. In multivariate analysis, LDL size was significantly related to several components of the insulin resistance syndrome, including triglycerides (inversely) and HDL cholesterol (positively). Although univariate relations were positive, LDL size was not significantly related to fasting insulin concentrations or body mass index in the multivariate model. LDL size also showed no relationship to apolipoprotein E phenotype. When LDL size was compared in individuals with and without CHD, no significant differences were observed, either in nondiabetic or diabetic individuals. We conclude that LDL size is most strongly related to lipoprotein components of the insulin resistance syndrome, especially plasma triglycerides. However, in this population with low LDL, it is not related to cardiovascular disease.

Aged↗
PubMed1997

The prevalence of diabetic retinopathy and associated risk factors among Sioux Indians.

OBJECTIVE: To estimate the prevalence of and risk factors for diabetic retinopathy among Sioux Indians of South Dakota. RESEARCH DESIGN AND METHODS: Strong Heart Study (SHS) participants with diabetes who are members of the Cheyenne River Sioux Tribe and the Oglala Sioux Tribe were invited to have ophthalmological examinations in 1991. A total of 417 people had eye examinations out of the 488 diabetic SHS participants of the two tribes (85% participation rate). Fundus photographs were obtained of each eye and graded for severity of retinopathy using the modified Airlie House Classification Scheme. Risk factors for retinopathy were determined from the SHS database. RESULTS: The prevalence of diabetic retinopathy among participants from these tribes was 45.3%. Risk factors associated with severity of retinopathy include mean fasting glucose, level. HbA1c, systolic blood pressure, urinary albumin-to-creatinine ratio, renal dialysis, and duration of diabetes. CONCLUSIONS: The prevalence of diabetic retinopathy among diabetic Sioux Indians is similar to or higher than the prevalence in other diabetic Indian and non-Indian populations. Aggressive glycemic and blood pressure control is urgently needed to reduce this high rate, and annual eye examinations to detect and treat diabetic retinopathy should be emphasized.

Aged↗
PubMed1997

Psychosocial barriers to health promotion in an American Indian population.

Northern Plains Indians (N = 200) completed the Indian Specific Health Risk Appraisal and measures assessing beliefs about risk factors and personal risk. Participants rated personal risk optimistically, judged their risk factor standing as superior to that of their peers, and neglected to consider risk factor standing when appraising personal risk. Moreover, participants were often not improving their standing on risk factors they considered relevant to their health. Such biases in health beliefs may prevent health interventions from being successful.

Adolescent↗
PubMed1996

Major electrocardiographic abnormalities among American Indians aged 45 to 74 years (the Strong Heart Study).

As part of the Strong Heart Study assessment of prevalent cardiovascular disease in middle-aged to elderly American Indians, the prevalence of major Minnesota code electrocardiographic (ECG) abnormalities was assessed in 4,531 participants aged 45 to 74 years (59% women) in selected tribal communities in Arizona, South and North Dakota, and Oklahoma. The overall prevalence of major ECG abnormalities was lowest in Arizona participants, (e.g., definite ECG myocardial infarction in 0.3% vs 1.8% in the other centers), although nearly two thirds of them had diabetes. One or more major ECG abnormality occurred in progressively more women (10.4% to 21.2%) and men (13.3% to 32%) (both p < 0.0001) from 45- to 54- to 55- to 64- and 65- to 74-year age groups, with the latter prevalence rates exceeding those in predominately white age peers in the Cardiovascular Health Study. Diabetes in women, but not in men, and hypertension in both genders showed positive associations with prevalence rates of major ECG abnormalities compatible with coronary artery disease or hypertensive cardiac hypertrophy. Hypercholesterolemia was not associated with ECG abnormalities except for definite myocardial infarction in women. In conclusion, major ECG abnormalities are common in middle-aged to elderly American Indians ,consistent with recent documentation of higher cardiovascular mortality in this population than in similar aged U.S. whites.

Adult↗
PubMed1996

Plasma lipids and lipoprotein concentrations among American Indians: comparison with the US population.

Lipoprotein measurements from the Third National Health and Nutrition Education Survey were used to estimate the need to measure fasting lipid concentrations and offer dietary and drug interventions in the US population. In this review, we compare the distribution of the Third National Health and Nutrition Education Survey population (according to National Cholesterol Education Program guidelines) with a contemporary sample of lipoprotein measurements in 4549 American Indians. Compared with data from the former, relatively fewer American Indians have cholesterol levels greater than 240 mg dl-1 and a much larger proportion have 'desirable' cholesterol levels less than 200 mg dl-1. The above guidelines, dictating measurement of fasting lipoprotein concentrations and dietary or drug intervention, take into account age, presence of cardiovascular risk factors and levels of both HDL- and LDL-cholesterol. The proportion of American Indians requiring these interventions is somewhat at less than the Third National Health and Nutrition Education Survey population, even though the American Indian population in this comparison is generally older (45-74 years of age) than the Survey participants (20 to more than 75 years of age). We review the literature concerning lipoprotein measurements in other American Indian and ethnic population groups that are undergoing rapid changes in lifestyle. In general, cardiovascular risk factors, including lipoprotein concentrations, are accumulating. These factors suggest that the public health impact of coronary heart disease will increase as these populations undergo further lifestyle changes.

Adult↗
PubMed1996

Apolipoprotein E polymorphism in American Indians and its relation to plasma lipoproteins and diabetes. The Strong Heart Study.

Apo E is an important genetic factor in the development of cardiovascular disease, which is the leading cause of death among American Indians. We investigated the occurrence of the apo E alleles and the relation between apo E polymorphism and blood lipoproteins and apoproteins in members of 13 American Indian communities in three geographic areas. The frequencies of the epsilon 2 alleles in American Indians are significantly lower than those in white Americans, with the lowest frequencies of epsilon 2 in American Indians who reside in Arizona. Levels of LDL cholesterol and apo B were highest in those with epsilon 4 and lowest in those with epsilon 2. Concentrations of HDL cholesterol and apo A-I, however, tended to be lowest in epsilon 4 and highest in epsilon 2. Concentrations of total and VLDL triglycerides were lowest in the epsilon 3 group and higher in groups epsilon 2 and epsilon 4. Differences in concentrations of LDL cholesterol, HDL cholesterol, apo B, and apo A-I with apo E polymorphism were greater in women than in men, and differences in total and VLDL triglyceride concentrations by apo E phenotype were greater in men. Relations of total and VLDL triglycerides with apo E phenotype were stronger in women after menopause. In addition, differences in nearly all lipid and apoprotein concentrations between postmenopausal women and premenopausal women were greater if they had epsilon 2. Relations between apo E phenotype and lipoproteins were seen in individuals with diabetes mellitus as well as in nondiabetics. Apo E was significantly related to glucose control in diabetic women; those with epsilon 3 had higher glucose and hemoglobin A1C concentrations. Our findings show that (1) American Indians have low frequencies of apo epsilon 2; (2) apo E phenotype can influence levels of VLDL, LDL, HDL, apo B, and apo A-I; (3) the associations of apo E polymorphisms with lipid parameters differ between men and women; and (4) the associations in women of apo E polymorphisms with lipid parameters are modified by menopausal status.

Aged↗
PubMed1996

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.

Aged↗
PubMed1996

Diabetes and coronary heart disease in American Indians: The Strong Heart Study.

Coronary heart disease (CHD) is the leading cause of death among American Indians. However, information on the prevalence of CHD and its association with known risk factors is limited. The purpose of the Strong Heart Study is to quantify CHD and its risk factors among three geographically diverse groups of American Indians. The population consists of 4,549 adults between 45 and 74 years of age in 13 Indian communities in Arizona, Oklahoma, and South and North Dakota. The phase I examination (1989-1991) revealed very high prevalence rates of diabetes that ranged from 33 to 72% in men and women in the three centers. Prevalence rates of definite myocardial infarction (MI) and definite CHD were higher in men than in women in all three centers (P < 0.0001) and in those with diabetes (P = 0.002 and P = 0.0003 in women and men respectively). Diabetes was associated with a relatively greater increase in prevalence of MI (prevalence rate = 3.8 vs. 1.9) and CHD (prevalence rate = 4.6 vs. 1.8) in women than in men. Logistic regression analysis indicated that the prevalence of CHD among American Indians was significantly related to age, diabetes, hypertension, albuminuria, percentage of body fat, smoking, high concentrations of plasma insulin, and low concentrations of HDL cholesterol. Lower prevalence rates of CHD were found in Arizona despite higher rates of diabetes, obesity, hypertension, and albuminuria; these lower rates may be in part related to lower smoking frequency and lower concentrations of total and LDL cholesterol. These findings from the baseline Strong Heart Study examination emphasize the relative importance of diabetes and its associated variables as risk factors for CHD among American Indian populations.

Adult↗
PubMed1996

Guidelines for prevention and control of hepatitis A in American Indian and Alaska Native communities.

The Aberdeen Area Indian Health Service, South Dakota Department of Health, and the Centers for Disease Control and Prevention have collaborated since 1985 to investigate hepatitis A in Indian communities in the Northern Plains and to implement clinical trials of hepatitis A vaccine. After licensure of the hepatitis A vaccine in February 1995, community wide immunization programs have been implemented effectively in several communities experiencing hepatitis A outbreaks. The state health department, tribal health departments, Indian Health Service facilities, Head Start programs and schools have provided hepatitis A immunizations to children aged 2-12 years in each of these communities after obtaining parental consent. Culturally-specific educational materials were developed and extensive health education efforts were provided by IHS and tribal programs. Hepatitis A contacts age 2-12 were offered the hepatitis A vaccine at the same time they were offered passive immunization with immune globulin. To date over 70% of parents contacted by letter or in person have returned consent forms to have their children immunized. Higher response rates were obtained in communities where home visits were made to explain this program in more detail. The outbreaks appear to have stopped after 70% or more of the children aged 2-12 years were immunized. Immunization programs are being implemented in all Northern Plains Indian communities utilizing hepatitis. A vaccine from the Vaccine For Children Program. These efforts will likely eliminate hepatitis A as a health problem for Indian communities.

Adolescent↗
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↗
PubMed1995

Diabetes and impaired glucose tolerance in three American Indian populations aged 45-74 years. The Strong Heart Study.

OBJECTIVE: To estimate prevalence rates of diabetes and impaired glucose tolerance (IGT) in three American Indian populations, using standardized diagnostic criteria, and to assess the association of diabetes with the following selected possible risk factors: age, obesity, family history of diabetes, and amount of Indian ancestry. RESEARCH DESIGN AND METHODS: This cross-sectional study involved enrolled members, men and women aged 45-74 years, of 13 American Indian tribes or communities in Arizona, Oklahoma, and South and North Dakota. Eligible participants were invited to the clinic for a personal interview and a physical examination. Diabetes and IGT status were defined by the World Health Organization criteria and were based on fasting plasma glucose and oral glucose tolerance test results. Data on age, family history of diabetes, and amount of Indian ancestry were obtained from the personal interview, and measures of obesity included body mass index, percentage body fat, and waist-to-hip ratio. RESULTS: A total of 4,549 eligible participants were examined, and diabetes status was determined for 4,304 (1,446 in Arizona, 1,449 in Oklahoma, and 1,409 in the Dakotas). In all three centers, diabetes was more prevalent in women than in men. Arizona had the highest age-adjusted rates of diabetes: 65% in men and 72% in women. Diabetes rates in Oklahoma (38% in men and 42% in women) and South and North Dakota (33% in men and 40% in women), although considerably lower than in Arizona, were several times higher than those reported for the U.S. population. Rates of IGT among the three populations (14-17%) were similar to those in the U.S. population. Diabetes rates were positively associated with age, level of obesity, amount of Indian ancestry, and parental diabetes status. CONCLUSIONS: Diabetes is found in epidemic proportions in Native American populations. Prevention programs and periodic screening should be implemented among American Indians. Standards of care and intervention have been developed by the Indian Health Service for individuals in whom diabetes is diagnosed. These programs should be expanded to include those with IGT to improve glycemic control or to reduce the risk of development of diabetes as well as to reduce the risk of diabetic complications.

Age Factors↗
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↗