Diabetes in American Indians. An overview.

OBJECTIVE: To review the growth of diabetes as a major health problem for American Indians and Alaska Natives. RESEARCH DESIGN AND METHODS: Pertinent studies of diabetes in Indians previously published are reviewed and compared with current data. RESULTS: Although diabetes rates may vary among different Indian tribes, diabetes has become a widespread health problem. CONCLUSIONS: Our understanding of the natural history of diabetes among Indians has improved, but better strategies to prevent complications and ultimately to prevent diabetes are urgently needed in Indian communities.

Diabetes and its complications among selected tribes in North Dakota, South Dakota, and Nebraska.

OBJECTIVE: To determine the prevalence and incidence rates of diabetes and two specific complications for selected American-Indian tribes in North Dakota, South Dakota, and Nebraska. RESEARCH DESIGN AND METHODS: A descriptive epidemiological study was conducted using ambulatory care data during 1987 for prevalence and diabetes registries and complication case reporting during 1988 from IHS facilities on reservations in these states. RESULTS: The Winnebago and Omaha tribes had the highest age-adjusted diabetes rates, with prevalence 8.8 times and incidence 7.7 times the respective U.S. rates. The diabetes prevalence rate of combined data for the Sioux was 3.7 times the U.S. rate. Among Sioux Indians, the age-adjusted incidence rate for ESRD was 4.8 times the American-Indian/Alaska-Native rate and 13.4 times the rate for U.S. whites. The proportion of new diabetes-related ESRD (86%) was almost 3 times greater than the general U.S. population rate (30%). Also, among the Sioux, the age-adjusted incidence rate for LEA (86.7/10,000 diabetic population) was 1.5 times higher than the U.S. rate; the proportion of diabetes-related LEA (84%) was 1.8 times higher than the general U.S. population rate (45%). CONCLUSIONS: The age-adjusted rates of diabetes and certain complications among these Northern Plains tribes are greater than the U.S. rates. Improved health services to detect and monitor diabetes and its complications and community-based prevention activities directed at the epidemic of diabetes among the various Indian tribes are urgently needed.

Diabetes in a northern Minnesota Chippewa Tribe. Prevalence and incidence of diabetes and incidence of major complications, 1986-1988.

OBJECTIVE: To determine the prevalence and incidence of diabetes, and the incidence of major diabetic complications, in a Chippewa Indian population. RESEARCH DESIGN AND METHODS: The format was a longitudinal population study that used active community and health center-based surveillance. The setting was a North American Indian reservation community of 4075 residents, served by an IHS clinic from 1986 to 1988. Patients were American Indians of Chippewa descent living on or near the Red Lake Reservation. RESULTS: Midway through the study, 346 people had been diagnosed with diabetes, which yielded an age- and sex-adjusted point prevalence of 148/1000 population. The adjusted rate for individuals > or = 25 yr of age was 252/1000 population, 3.82 times the U.S. rate (CI 2.95-4.93). Some 97 new cases of diabetes were identified for an age- and sex-adjusted average annual incidence of 17/1000 population. The incidence of hospitalization for LEA was 26/1000 diabetic person-yr, 4.3 times the 1978 U.S. rate (95% CI 2.8-6.8). Twelve individuals developed proliferative retinopathy, for an incidence of 12/1000 diabetic person-yr. Newly diagnosed ESRD incidence was 6/1000 diabetic person-yr. Twenty-three acute myocardial infarctions were observed, yielding an incidence of 22/1000 diabetic person-yr. CONCLUSIONS: Diabetes and its complications are prevalent in this Chippewa population, and further surveillance is needed to evaluate the effectiveness of prevention efforts.

Epidemiology of lower-extremity amputations in the Indian Health Service, 1982-1987.

OBJECTIVE: To describe the LEA experience among IHS diabetic patients. RESEARCH DESIGN AND METHODS: A cross-sectional study of hospital discharges for nontraumatic LEAs from 1982 to 1987 in four IHS areas was conducted. RESULTS: Incidence rates of first LEA in the study period increased with increasing age. Compared with nondiabetic subjects, diabetic patients had increased risks in each age-group, with those between the ages of 15 and 44 yr having a 158-fold increased risk. The average annual age-adjusted incidence rates of all LEAs among diabetic subjects in the Tucson (240.8/10,000) and Phoenix (203.1/10,000) IHS areas were substantially higher than the rates for the U.S. (73.1/10,000), Navajo (74.0/10,000), and the Oklahoma (87.3/10,000) IHS areas. CONCLUSIONS: LEA rates varied in different IHS areas. Reasons for these findings need to be evaluated, but may include IHS area differences in preventive health-care practices or risk factors for LEA.

Prevalence of diagnosed diabetes among American Indians and Alaska Natives, 1987. Estimates from a national outpatient data base.

OBJECTIVE: To estimate the prevalence of diagnosed diabetes among American Indians and Alaska Natives served by the IHS. RESEARCH DESIGN AND METHODS: This was a cross-sectional study of the 1987 IHS national outpatient data base. RESULTS: Prevalence rates of diagnosed diabetes determined from the IHS outpatient data base were consistent with recent studies of diabetes in different IHS areas. IHS-wide, age-adjusted prevalence was 69/100,000, or 2.8 times the U.S. rate. There was considerable variation in prevalence rates of diabetes throughout the country, with rates ranging from 15.3/100,000 in Alaska to 119.2/100,000 in southern Arizona. CONCLUSIONS: This study documented the high prevalence of diabetes among American Indians and Alaska Natives and the wide variation in rates between different tribal groups. This study also demonstrated the feasibility of using an outpatient data base to estimate rates of disease that have uniform methods of diagnosis and result in frequent clinic visits.

Clinical hypertension and its interaction with diabetes among American Indians and Alaska Natives. Estimated rates from ambulatory care data.

OBJECTIVE: To estimate the prevalence of clinical hypertension and describe the coexistence with diabetes in American Indian and Alaska Native communities. RESEARCH DESIGN AND METHODS: A cross-sectional study of outpatient visits for hypertension and diabetes over a 1-yr period (1 October 1986 to 30 September 1987) in IHS facilities was conducted. RESULTS: The 1987 estimated age-adjusted prevalence of diagnosed hypertension for this group was 10.9/100 for people > or = 15 yr of age. Thirty-seven percent of diabetic patients were diagnosed with hypertension. The relative risk of hypertension in the diabetic populations compared with the nondiabetic population varied from 4.7 to 7.7 among the different IHS areas. CONCLUSIONS: Despite high rates of diabetes and obesity, hypertension rates were relatively low among American Indians and Alaska Natives when compared with other ethnic groups in the U.S.

Diabetes-associated mortality in Native Americans.

OBJECTIVE: To describe diabetes-associated mortality among Native Americans. RESEARCH DESIGN AND METHODS: In this population-based study, we analyzed diabetes-associated mortality data from the IHS and the NCHS. We also examined diabetes data from the 1986 NMFS. RESULTS: IHS area-specific diabetes mortality rates for 1984-1986 ranged from 10 to 93/100,000, compared with 15/100,000 for the total U.S. population. NCHS data for the same period listed diabetes as the underlying cause of 708 deaths among Native Americans and the contributory cause of 1252 deaths; 63% of the latter deaths were attributable to circulatory diseases. The 1986 NMFS demonstrated that Native American heritage is underreported by 65% on death certificates. Using deaths identified as Native American by NMFS, the age-adjusted mortality rate for diabetes as the underlying cause for Native Americans (96/100,000) was 4.3 times that for whites and two times that for blacks. Where diabetes was a contributory cause of death, the mortality rate for Native Americans (264/100,000) was 3.7 times that for whites and 2.4 times that for blacks. CONCLUSIONS: The excessive diabetes-associated mortality among Native Americans is consistent with other indicators of the magnitude of the diabetes problem in this population. Further epidemiological research and expanded diabetes control interventions are needed.

Improving diabetes care for American Indians.

In 1986, a diabetes control program was implemented in the Billings area of the IHS. Baseline health-care practices in the program were described using a structured audit. The program included adoption of the IHS Minimum Standards of Care for diabetes, technical assistance, and professional and patient education. A second audit was performed in 1988. Care practices improved significantly for all facilities in 7 of 10 parameters measured. Facilities that implemented key program activities showed more overall improvement in screening practices, education, and immunization than those that did not organize diabetes care. Factors associated with improved care practices include establishment of a coordinated, multidisciplinary diabetes team with regular meetings, acceptance of standards of care by the medical staff, use of flow sheets by multiple providers, and diabetes-related professional and patient education sessions.

Investigation of Laboratory cross-contamination of Mycobacterium tuberculosis cultures.

Many clinicians and laboratory personnel are unaware that a culture positive for Mycobacterium tuberculosis may represent contamination. Laboratory cross-contamination with the M. tuberculosis laboratory control strain (H37Ra) occurs infrequently and therefore demands heightened awareness and recognition. We report 3 occurrences of laboratory cross-contamination from the same laboratory. These occurrences illustrate the importance of interpreting laboratory results in conjunction with the patient's clinical presentation. Failure to recognize laboratory cross-contamination with M. tuberculosis leads to both erroneous administration of unnecessary medications and expenditure of resources required to conduct contact investigations.

A preventable outbreak of tuberculosis investigated through an intricate social network.

In 1998, a city in Indiana reported 4-fold increase in the number of cases of tuberculosis (TB). An investigation to assess the increase in cases and to identify possible epidemiologic links among persons with TB identified 41 cases of active TB. Epidemiologic links and/or matching DNA fingerprints were identified for 31 patients (76%). The majority of these patients were members of a single social network within the community. Links for most of these patients were identified after multiple interviews with patients and their contacts. TB control activities in the county were limited prior to the identification of the outbreak. At least 24 cases may have been preventable. This outbreak may have been prevented with prompt case identification and effective contact tracing and screening during the years before the outbreak. The use of social networks should be considered in the investigation of outbreaks that involve difficult-to-reach populations. TB control measures should be maintained in areas with historically low TB incidence.

Comparison of AIDS and HIV antibody surveillance data in Colorado.

We compared cumulative surveillance data for AIDS (May 1982-December 1986) and persons with positive HIV antibody tests (July 1985-December 1986) to examine the adequacy of each surveillance system in directing public health disease control activities. Neither AIDS nor HIV antibody surveillance data alone described the total extent of HIV infection. The geographic distribution of persons with positive HIV antibody tests was more widespread than the distribution of AIDS cases for all demographic and transmission categories. Ideally, preventive efforts should be based on a comprehensive surveillance system that indicates all persons who are infectious with HIV.

Tuberculin skin test screening in schoolchildren in the United States.

OBJECTIVE: To determine the current practices and results of tuberculin skin test (TST) screening of schoolchildren in the United States. METHODS: Tuberculosis program staff in all states and the District of Columbia were asked about current requirements, practices, and results of school-based TST screening. RESULTS: Thirty-four states and the District of Columbia (69%) reported no current statewide statutes or policies for tuberculin screening of schoolchildren, and 10 (19%) reported having statewide requirements. In 6 states (12%), requirements were instituted at the local level, and 24 localities in these states were known to require screening. Of the 34 areas requiring screening, 18 (53%) screened all new entrants, 7 (21%) screened children in specific grades, and 9 (26%) used other criteria for screening. TST results were collected for 26 (76%) of 34 areas, and 6 areas collected results of follow-up evaluation of tuberculin-positive children. Additionally, 8 localities in 7 states with no screening requirements conducted tuberculin surveys. Sixteen areas provided results. In 7 of the 8 areas that collected information about birthplace, less than 2% of US-born children were tuberculin positive; foreign-born children had rates 6 to 24 times higher than US-born children. TST screening identified new cases of tuberculosis, less than 0.02% of the children screened. CONCLUSIONS: School-based tuberculin screening identified low rates of positive TST results in US-born children. Resources should be directed toward screening children at high risk for tuberculous infection, as recommended by the American Academy of Pediatrics and the Advisory Committee for Elimination of Tuberculosis.

Tuberculosis in a day-care center, Kentucky, 1993.

In November, 1993, a 33-month-old child in a day-care center was diagnosed with tuberculosis (TB). To identify her source of infection, close contacts, other day-care children and staff were screened by tuberculin skin test (TST). TB registry and medical/laboratory records were reviewed. The only 2 community TB cases reported in the past 3 years were investigated. Of 164 children 2 were diagnosed with TB; their TSTs were > or = 10 mm but no specimens were obtained. Six children had TSTs > or = 5 mm. Of these 4 had TST conversions between December, 1993, and March, 1994. There were no additional positive TST children in June, 1994. No TB case was identified among staff or parents. A possible epidemiologic link with the index case was found for 1 community case. No source of infection was found for the other children. Possible explanations for not finding a source are: an as yet unidentified case in the day-care center or community; or false positive TST results in children related to low community prevalence of TB infection.

Tuberculosis in children younger than five years old: New York City.

We examined medical and health department records for children < 5 years of age with suspected or confirmed tuberculosis reported to the New York City Health Department from January, 1992, through June, 1992, in order to describe the epidemiology of tuberculosis in young children and identify prevention strategies. Forty-seven children were treated for suspected or confirmed tuberculosis. Sixty-two percent (21 of 34) were foreign-born (n = 11) or had foreign-born caretakers (n = 10). A source case was found for 10 of 47 (21%) children; for 8 the adult source was diagnosed before the child. One child was human immunodeficiency virus-seropositive, however, 83% of children and 70% of adult source cases did not have human immunodeficiency virus test results available. Health care providers should test children at high risk for tuberculosis infection as recommended by the American Academy of Pediatrics and improve contact tracing to identify children exposed to adults with tuberculosis. Because most cases of tuberculosis in children are diagnosed clinically rather than by isolating Mycobacterium tuberculosis, identification of the source case is important for selecting appropriate treatment.

Nosocomial transmission of human immunodeficiency virus and subsequent transmission of multidrug-resistant tuberculosis in a healthcare worker.

A phlebotomist with nosocomially acquired human immunodeficiency virus infection developed tuberculosis 10 months after exposure to multidrug-resistant Mycobacterium tuberculosis during a nosocomial outbreak. Healthcare workers with immunosuppression are at increased risk of tuberculosis if infected and, if exposed, should be considered for preventive therapy regardless of tuberculin skin-test status.

Multidrug-resistant Mycobacterium tuberculosis in an HIV dental clinic.

OBJECTIVE: To investigate possible transmission of multidrug-resistant tuberculosis (MDR-TB) in a dental setting. DESIGN: A retrospective, descriptive study of dental workers (DWs), patients, and practice characteristics. PATIENTS: Two dental workers (DW1 and DW2) with acquired immunodeficiency syndrome and MDR-TB. SETTING: A hospital-based (Hospital X) human immunodeficiency virus (HIV) dental clinic in New York City. METHODS: To identify dental patients with tuberculosis (TB), patients treated in the dental clinic at Hospital X during 1990 were cross-matched with those listed in the New York City Department of Health Tuberculosis Registry. Mycobacterium tuberculosis isolates from both DWs and from dental patients with TB were tested for antimicrobial susceptibility and typed by restriction fragment length polymorphism (RFLP) analysis. Infection control practices were reviewed. RESULTS: M tuberculosis isolates infecting DW1 and DW2 were resistant to isoniazid and rifampin and had identical RFLP patterns. DW1 and DW2 worked in close proximity to each other in a small HIV dental clinic in Hospital X during 1990. Of 472 patients treated in the dental clinic in 1990, 41 (8.7%) had culture-proven M tuberculosis infection. Of these 41, 5 had isolates with resistance patterns similar to both DWs; however, for four available isolates, the RFLP patterns were different from the patterns of the DWs. Sixteen of the 41 patients received dental treatment while potentially infectious. Dental patients were not routinely questioned about TB by dental staff, nor were all dental staff screened routinely for TB. No supplemental environmental measures for TB were employed in the dental clinic in 1990. CONCLUSIONS: Our investigation suggests that MDR-TB transmission may have occurred between two DWs in an HIV dental clinic. Opportunities for transmission of TB among dental staff and patients were identified. TB surveillance programs for DWs and appropriate infection control strategies, including worker education, are needed to monitor and minimize exposure to TB in dental settings providing care to patients at risk for TB.

Transmission of multidrug-resistant Mycobacterium tuberculosis among persons exposed in a medical examiner's office, New York.

OBJECTIVE: To determine the prevalence of and risk factors for having a positive tuberculin skin test (TST) result among employees at a medical examiner's office (MEO). DESIGN: Cohort study, environmental investigation. SETTING: Several employees at a medical examiner's office were found to have positive TST results after autopsies were performed on persons with multidrug-resistant tuberculosis (MDR-TB). PARTICIPANTS: Employees of the MEO. RESULTS: Of 18 MEO employees, 5 (28%) had a positive TST result; 2 of these 5 had TST conversions. We observed a trend between TST conversion and participation in autopsies on persons with MDR-TB (2 of 2 converters versus 3 of 13 employees with negative TST; relative risk = 4.3; 95% confidence interval 1.61 to 11.69; P = 0.10). The environmental investigation revealed that the autopsy room was at positive pressure relative to the rest of the MEO and that air from the autopsy room mixed throughout the facility. CONCLUSIONS: A systematic approach to preventing transmission of Mycobacterium tuberculosis in autopsy suites should include effective environmental controls and routine tuberculin skin testing of employees.

Pseudo-outbreak of tuberculosis in an acute-care general hospital: epidemiology and clinical implications.

A 10-fold increase in patients with Mycobacterium tuberculosis-positive specimens in one hospital laboratory prompted an investigation. Clinical and epidemiological data, along with M tuberculosis DNA fingerprinting results, indicated that laboratory contamination led to nine false-positive M tuberculosis cultures. Pseudo-infection should be considered in patients with unusual tuberculosis presentations, negative acid-fast bacilli smears, and only one positive culture with a low colony count.

Tuberculosis screening in private physicians' offices, Pennsylvania, 1996.

OBJECTIVE: To assess tuberculin skin testing practices of physicians after community-wide screening of 1400 children exposed to a pediatrician with active tuberculosis (TB). DESIGN: A self-administered questionnaire. SETTING: Medium-sized city in eastern Pennsylvania. PARTICIPANTS: Pediatricians and family practitioners seeing pediatric patients. MAIN OUTCOME MEASURES: Percentages of physicians who followed published recommendations for placement and reading of TB skin tests published by the American Academy of Pediatrics (AAP) and the Centers for Disease Control and Prevention (CDC). RESULTS: Questionnaires were completed by 60/80 (75%) physicians. The 60 physicians had practiced a mean of 17 years (range 3-38 years), and only one did not do TB skin testing for pediatric patients. The 59 physicians doing TB skin testing reported routinely tuberculin testing more than 900 children per month. Only 8/59 (14%) physicians followed published guidelines for placement and reading of tuberculin tests. Those physicians screened 158 (17%) of the pediatric patients undergoing TB skin testing in a typical month. CONCLUSION: In this community where a highly publicized TB case prompted massive pediatric screening, most physicians seeing children in private practice do not follow standard TB skin testing guidelines. Increased understanding of how private-practice physicians learn about and decide to use recommended standards are needed if tuberculin tests are to be correctly performed and TB appropriately diagnosed.

Outbreak of multidrug-resistant tuberculosis at a methadone treatment program.

SETTING: An out-patient methadone treatment program MTP). OBJECTIVE: To investigate transmission of multidrug-resistant tuberculosis (MDR-TB) in the MTP. DESIGN: Cases were defined as MTP clients or staff who developed TB between 1 January 1994 and 1 January 1996, with at least one positive culture for Mycobacterium tuberculosis resistant to isoniazid and rifampin. Contacts were identified, located and evaluated. RESULTS: Thirteen cases of MDR-TB occurred among 462 clients and staff. One fifth (6/30) of the members of a counseling group for human immunodeficiency virus (HIV) infected clients developed MDR-TB. Individuals known to be HIV positive were at greater risk for TB than those who were HIV negative (RR 5.2, 95%CI 1.2-22.7). Of 449 clients and staff identified as contacts, 393 (87.5%) were located and screened. Among those with a negative baseline tuberculin skin test, 18.5% (56/303) were skin test converters. Attendance at the MTP during a period when the index case was infectious was associated with an increased risk of conversion (RR 2.5, 95%CI 1.1-6.0). CONCLUSION: Extensive transmission of MDR-TB occurred at an out-patient MTP serving numerous clients with HIV infection. This outbreak underscores the importance of developing effective strategies to prevent TB transmission in this setting.