Assessment of the ability of the triglyceride to high density lipoprotein cholesterol ratio to discriminate insulin resistance among Caribbean-born black persons with and without Hispanic ethnicity.

OBJECTIVE: The objective of this research was to determine if the triglyceride (TG) to high density lipoprotein (HDL) cholesterol (TG/HDL) ratio has similar utility for discriminating insulin resistance in Caribbean-born black persons with and without Hispanic ethnicity. METHODS: Serum lipids, glucose and insulin were determined and compared for 144 Hispanic blacks and 655 non-Hispanic blacks living in the US Virgin Islands. Area under the receiver operating characteristics (AUROC) curve statistics were used to evaluate the ability of the TG/HDL ratio to discriminate insulin resistance in the two ethnic groups. RESULTS: Hispanic blacks had significantly higher levels of triglycerides and insulin resistance and a lower level of HDL cholesterol than non-Hispanic blacks. The AUROC curve for the ability of the TG/HDL to discriminate insulin resistance was 0.71 (95% CI = 0.62, 0.79) for Hispanic blacks and 0.64 (95% CI = 0.59, 0.69) for non-Hispanic blacks. CONCLUSIONS: Among Caribbean-born black persons living in the US Virgin Islands, the TG/HDL ratio is a useful screening measure for discriminating insulin resistance in those with Hispanic ethnicity but not in those without Hispanic ethnicity.

Assessment of the disturbances in metabolic homeostasis: a hypothesis of synergism.

Based on the hypothesis that a synergistic interaction between triiodothyronine (T(3)) and insulin contributes to abnormalities in glucose and other metabolic pathways, the mechanisms underlying the impairment of metabolic homeostasis (MH) and the development of type-2 diabetes (DM) were investigated via a proposed homeostatic model, [(FG*TG)/T3*FI)]. The MH model characterizes the relationship between T(3) and insulin and the levels of triglycerides (TG), fasting insulin (FI), and fasting glucose (FG) and is introduced as a clinical method to assess insulin sensitivity and the status of metabolic homeostasis in lieu of current screening models advocated by the by American Diabetic Association (ADA). The present study validated the hypothetical model in a sample of 110 African-American women.

A hypothesis of synergism: the interrelationship of T3 and insulin to disturbances in metabolic homeostasis.

While the role of abnormal insulin homeostasis in the pathogenesis of Type-2 diabetes mellitus is well established, the importance of the canonical role of T(3) on Type-2 diabetes or the homeostasis of glucose, lipid, and energy balance has not been addressed. Based on the available evidence from molecular biology, the pivotal regulatory role of T(3) in major metabolic pathways and glycemic control can be delineated by mapping the specific action sites of T(3) and insulin on the metabolic pathways of the glucose-lipid cycle. The current paper presents an integrative hypothesis of the synergistic relationship of T(3) and insulin in metabolic homeostasis and abnormalities.

Should body size preference be a target of health promotion efforts to address the epidemic of obesity in Afro-Caribbean women?

OBJECTIVE: To determine if 1) Afro-Caribbean women prefer large body sizes, 2) the body size preference of Afro-Caribbean men and women are associated, 3) women's preferences are associated with increased risk of obesity or with weight management behaviors. DESIGN: Population samples of 314 and 487 women, ages 20-55 years, were recruited on Barbados and Dominica with response rates of 74% and 77%, respectively. Body size preferences, stress related variables, and demographic data were ascertained by questionnaire. Height and weight were also measured. On Barbados, body preference data were collected from male partners of participants, and data on intentions to perform weight management behaviors were collected from 175 women. RESULTS: Most women preferred body sizes within normal limits, although women on Dominica had a slightly larger ideal body size (IBS) than did Barbadian women (P<.05). On both islands, the size that women thought men preferred was related to their IBS (P<.0001). Likewise, IBS was associated with increased odds of being overweight (P<.001), however most overweight women (>75%) wanted to be smaller. IBS was not related to the intention to exercise or to eat high fat foods. CONCLUSIONS: It is unlikely that body size preference poses a barrier to intervention efforts to reduce the prevalence of overweight in Afro-Caribbean women.

The use of capture-recapture methods to monitor diabetes in Dominica, West Indies.

The aim of this project was to evaluate the utility of capture-recapture (CR) estimation methodology, together with easily accessible sources of information, for monitoring the frequency of diabetes mellitus in a developing country. On the Caribbean island of Dominica, from July 1995 through July 1996, the names were collected of all individuals who were listed in at least one of three sources as having been diagnosed with diabetes during 1995. The sources were the membership list of the Dominica Diabetic Association, a register of patients in seven regional health centers, and clinic records of the Princess Margaret Hospital, which is the main hospital on the island. Capture-recapture techniques were used to estimate the number of Dominicans with diagnosed diabetes who were missed by all three sources of information and to evaluate dependencies among the sources. An ascertainment-corrected prevalence estimate of diagnosed diabetes was then calculated. The three sources identified a total of 1,945 different individuals. When this number was compared with the ascertainment-corrected estimate obtained with CR methodology (2,688), it appeared to represent only 72.3% of the true prevalence of diagnosed diabetes. Most of the under-ascertainment by the data sources was due to cases that were missed in the urban area of the island. This approach to disease monitoring may be useful for other Caribbean countries. However, standardized procedures for collecting and reporting prevalence and morbidity data are needed to maximize its accuracy and cost-effectiveness.

Incidence of childhood-onset IDDM in black African-heritage populations in the Caribbean. The Caribbean African Heritage IDDM Study (CAHIS) Group.

OBJECTIVE: To compare incidence rates of childhood-onset IDDM among black African-heritage populations age 0-19 years in the Caribbean region. RESEARCH DESIGN AND METHODS: Population-based registries for IDDM were established on the eastern Caribbean islands of Antigua, Barbados, Dominica, St. Croix, St. Kitts, St. Thomas, and Tortola using standardized criteria from the World Health Organization (WHO) Multinational Project for Childhood Diabetes (DiaMond). Average annual incidence rates (IR) with 95% CI for 0-19 years olds were computed using the DiaMond Registry program for the 5-year period from 1989 to 1993. Poisson regression analysis was used to determine differences in incidence rates. RESULTS: The highest incidence rate for 0-19 year olds was for the black African-heritage population of St. Croix (IR 10.09 per 100,000; 95% CI 4.35-19.89), one of the U.S. Caribbean islands. A significant (P < 0.05) 3.9 variation in IDDM incidence across the registries was found when the IR for St. Croix was compared to the IR for Barbados (IR 2.57 per 100,000; 95% CI 0.90-4.64). CONCLUSIONS: The variation in childhood-onset IDDM incidence rates among the black populations of the eastern Caribbean islands is consistent with the geographic variation in IDDM incidence seen among African Americans in the U.S. Variation in incidence rates of childhood diabetes in black populations may reflect differences in level of white genetic admixture or exposure to environmental diabetogenic agents.

Incidence of childhood-onset IDDM in black African-heritage populations in the Caribbean. The Caribbean African Heritage IDDM Study (CAHIS) Group

OBJECTIVES: To compare incidence rates of childhood-onset IDDM among black African-heritage populations age 0-19 years in the Caribbean region. RESEARCH DESIGN AND METHODS: Population-based registries for IDDM were established on the eastern Caribbean islands of Antigua, Barbados, Dominica, St. Croix, S t. Kitts, St. Thomas, and Tortola using standardized criteria from the World Health Organization (WHO) Multinational Project for Childhood Diabetes (DiaMond). Average annual incidence rates (IR) with 95 percent CI for 0-19 years olds were computed using the DiaMond Registry program for the 5-year period from 1989 to 1993. Poisson regression analysis was used to determine differences in incidence rates. RESULTS: The highest incidence rate for 0-19 year olds was for the black African-heritage population of St. Croix (IR 10.99 per 100,000; 95 percent CI 4.35-19.89), one of the U.S. Caribbean islands. A significant (P < 0.05) 3.9 variation in IDDM incidence across the registries was found when the IR for St. Croix was compared to the IR for Barbados (IR 2.57 per 100,000; 95 percent CI 0.90-4.64). CONCLUSION: The variation in childhood-onset IDDM incidence rates among the black population of the eastern Caribbean islands is consistent with the geographic variation in IDDM incidence seen among African Americans in the U.S. Variation in incidence rates of childhood diabetes in black populations may reflect difference in level of white genetic admixture or exposure to environmental diabetogenic agents. (AU)

A twofold excess mortality among black compared with white IDDM patients in Allegheny county, Pennsylvania. Pittsburgh DERI Mortality Study Group.

OBJECTIVE: To examine the long-term mortality experience of blacks who develop IDDM in childhood. RESEARCH DESIGN AND METHODS: The 11-25-year mortality status of individuals with IDDM who participated in the Diabetes Epidemiology Research International (DERI) Mortality Study was verified as of 1 January 1990 for 1,008 (94%) of the 1,076 individuals in the study. Life-table analysis was performed, and race-specific rates were determined for the final sample. RESULTS: Among black patients, 14.9% died compared with 6.6% of the white patients after a maximum of 25 years of follow-up. African-Americans experienced an age-adjusted mortality rate that was over twice that of whites for the entire period (9.4 vs. 3.8 per 1,000 person-years, respectively; P < 0.05) and at each 5-year interval of follow-up. Among blacks, the mortality rate for females (15.9/1,000 person-years) was 8.4 times (P < 0.05) that of males (1.9/1,000 person-years). In contrast, this sex difference was not seen among whites. Acute complications of diabetes accounted for 40% of the mortality in the black patients, while only 23% of the white patients died from acute causes. CONCLUSIONS: The data suggest that some of the excess mortality in black IDDM patients may be preventable.

Markedly increased renal disease mortality and incidence of renal replacement therapy among IDDM patients in Japan in contrast to Allegheny County, Pennsylvania, USA. Diabetes Epidemiology Research International (DERI) U.S.-Japan Mortality Study Group.

The aim of this study was to evaluate factors related to the markedly increased risk of dying from diabetic renal disease in Japanese insulin-dependent diabetic patients compared to those in the USA. The study was based on two population-based cohorts consisting of 1374 cases from Japan and 995 cases from Allegheny County, Pennsylvania, USA, who were diagnosed between 1 January 1965 and 31 December 1979. The living status and dialysis experience were determined as of 1 January 1990. The duration-adjusted renal-failure-related mortality rates in the Japanese cohort and the USA cohort were 277.2 and 130.9 per 100,000 person-years, and the duration-adjusted incidence rates of dialysis were 564.9 and 295.6 per 100,000 person-year, respectively. After adjustment for sex, age at onset, calendar year of onset, and duration of diabetes, individuals with insulin-dependent diabetes in the Japanese cohort were still 2.4-fold more likely to receive dialysis compared to those in the USA cohort. Ten of the 36 renal-failure-related deaths in the Japanese cohort had never been treated by dialysis, while all renal-failure-related deaths in the USA cohort had been treated by dialysis. Survival after initiation of dialysis in the Japanese cohort was virtually the same as the USA cohort. These data suggest that a greater frequency of diabetic end-stage renal disease and reduced access to acceptance at dialysis underlie much of the excess of diabetic renal deaths in Japan.

Diabetes in newly diagnosed Zanzibari patients: 1986-1989.

Few data exist on the impact of diabetes mellitus, particularly the insulin-dependent subtype, in many parts of Africa. The importance of diabetes as a public health problem in the East African Islands of Zanzibar was assessed through prospective registration of all newly diagnosed diabetic individuals who attended the diabetic clinic at Mnazimmoja Hospital from January 1986 to December 1989. A total of 323 diabetic patients, 192 men and 131 women, were diagnosed. Two hundred fifty-three (78.3%) individuals had noninsulin-dependent diabetes mellitus (NIDDM), 61 (18.9%) had insulin-dependent diabetes mellitus (IDDM), and 9 (2.8%) had diabetes of uncertain type. Two hundred twenty-six (70%) of the patients were town residents, 62 (19.2%) had office jobs, and 84 (26%) were laborers. The majority of the patients presented with the classic symptoms of diabetes. A positive family history of diabetes was found in 35 (13.8%) and 4 (6.6%) of the NIDDM and IDDM cases respectively. Hypertension was diagnosed in 29 (11.5%) of all NIDDM individuals while obesity was present in only 41 (16.2%) of all NIDDM patients. These data suggest that diabetes is a problem of major public health importance in the Islands of Zanzibar.

Ascertainment corrected rates: applications of capture-recapture methods.

Accurate rates, though fundamental to epidemiology, are often very difficult to obtain. Incidence, prevalence, and mortality rates have traditionally been established through either passive reporting surveillance systems, through active surveillance systems, or by a combination of the two methods. Typically, when researchers employ these approaches they do not formally evaluate or correct for the degree of underascertainment. Undercount of cases is a potent determinant of rates which we cannot continue to ignore. We believe all rates should be adjusted for underascertainment in order to achieve a truer picture of the risk and risk factors of disease. Here, we present a procedure to ascertainment correct rates based upon well established capture-recapture methods.

Management of malaria in Zanzibar.

Malaria remains to be a major cause of morbidity and mortality in most African countries. Chloroquine resistance is one of the major contributing factors in many parts of the continent. Besides plasmodia parasite mutation, improper management of malaria cases and the absence of standardised management guidelines for the treatment of malaria may play a role in increasing the existing drug resistance. In this retrospective study which involved 400 patients at the Mnazimmoja Hospital, Zanzibar, chloroquine was found to be the most popular anti-malarial drug prescribed to 369 (92.25%) of the patients. A full standard chloroquine regimen (25 mg-base/Kg) was provided to about 88.15% (238 out of 270) of all admitted patients treated with chloroquine alone or in combination with other drugs. Prescriptions of multiple antimalarials at a time were found in 97 (24.25%) of the cases. The duration of a prescribed chloroquine course was 3 days (WHO recommendation) in 289 (78.32%), less than 3 days in 49 (13.28%) and more than 3 days in 31 (8.40%) of the patients. The possible roles of under-dosage and incomplete courses of physician and self-prescribed chloroquine regimens in increasing chloroquine resistance are discussed.

Insulin dependent diabetes mellitus in the 21st century and beyond a model disease for global health? (A review).

During the past twenty years there has been a rapid rise in the numbers of papers evaluating the incidence of childhood diabetes. Childhood diabetes has emerged as the non-communicable disease with the largest geographic coverage across the world. The incidence data are employed to forecast into the future. It is evident that both the United States and Europe will be confronted with an ever increasing burden of diabetes. It is argued that the monitoring of childhood diabetes should move into the public health sphere by making it a reportable disease. This would set the stage for public health surveillance of not only childhood diabetes but of all non-communicable diseases in the 21st century. The current paper overviews where we have come in the area of insulin-dependent diabetes mellitus epidemiology. Moreover, it projects into the future as to where Type 1 diabetes epidemiology can head. It is argued that Type 1 diabetes epidemiology can become the model disease to transform the current global approaches to health.

Evaluation of type 1 diabetes in black African-heritage populations: no time for further neglect. Diabetes Epidemiology Research International Group.

Heritage studies involving populations that share a common genetic background but reside in different geographic areas have provided important insights into the aetiology of Type 1 diabetes. While Type 1 diabetes heritage research has focused on Iberian, Arab, Italian, Indian (Asian), and Oriental groups, little attention has been paid to the evaluation of the disease in populations with black African ancestry. Epidemiological data on the occurrence of Type 1 diabetes in New World black populations have thus far been limited to a few studies conducted mainly in African-Americans. Moreover, much of the available data is not population-based and are of limited value for making generalizations about the black populations studied. Despite the limitations, there is evidence that these populations may be important for studying the aetiology and natural history of Type 1 diabetes. Increased research in this area is warranted and should be based on population-based cohorts.

Monitoring the incidence of myocardial infarctions: applications of capture-mark-recapture technology.

It is critical to monitor the incidence of myocardial infarction. Typically, death certificates have been used as a proxy for incidence, however, these have been found to be crude as they lag behind changes in incidence. In the last decade several myocardial infarction registries have been established, however, these registries are still too limited in geographical spread to assess either national or global trends of heart attack. Here we suggest that employing an alternate approach, that of capture-mark-recapture, would be helpful to provide accurate monitoring both within and between countries. This method would complement existing registries by providing a simple and inexpensive means to provide accurate heart attack data across broad geographical areas and time.

Epidemiology of childhood IDDM in U.S. Virgin Islands from 1979 to 1988. Evidence of an epidemic in early 1980s and variation by degree of racial admixture.

OBJECTIVE: The epidemiology of insulin-dependent diabetes mellitus (IDDM) was evaluated in a predominantly black population in the U.S. Virgin Islands. RESEARCH DESIGN AND METHODS: Primary ascertainment of diabetic subjects was by retrospective review of hospital and clinic records, and IDDM was defined by Diabetes Epidemiology Research International Group criteria. RESULTS: For the period 1979-1988, 28 children less than 15 yr of age were diagnosed with IDDM resulting in an average annual IDDM incidence rate (IR) of 7.5/100,000 (95% confidence interval 4.7-10.3). A significant increase in IDDM incidence (P less than 0.01) was observed when the IR rose to 28.4/100,000 in 1984. White children had the highest IR (28.9/100,000). The IR for Hispanics (7.2/100,000) was slightly higher than that for blacks (5.9/100,000). Among black children, a slight but nonsignificant male excess in incidence was observed (male-female ratio 1.5). When black or Hispanic patients were compared with age-matched control subjects with respect to grandparental race, the diabetic subjects had a greater percentage of white ancestry (P less than 0.02 and P less than 0.05, respectively). The incidence of IDDM in Caribbean blacks (West Indians) in the U.S. Virgin Islands was similar to blacks in the U.S. CONCLUSIONS: The epidemic of IDDM in 1984 provides support for a possible pandemic in the early 1980s.

Development of a registry for diabetes in persons 0-19 years of age in the U.S. Virgin Islands.

A juvenile-onset diabetes registry was recently established in the United States Virgin Islands. Hospital and clinic records were used as the primary sources of case data, while data procured through a physician survey and mass media campaign were used to assess the completeness and validity of the registry listings. The data indicated that 39 people 0-19 years old developed diabetes during the study period (1 January 1979-31 December 1988), of whom 36 probably had Type 1 diabetes. Completeness of the primary source data was estimated at 92.3% and validity seemed very good (around 100%). Evaluation of these registry data has provided new insights into the epidemiology of Type 1 diabetes in the U.S. Virgin Islands.