High incidence of childhood-onset IDDM in Kuwait. Kuwait Study Group of Diabetes in Childhood

OBJECTIVE

To determine the incidence of insulin-dependent diabetes mellitus (IDDM) in children aged 0-14 years in Kuwait, as part of the World Health Organization Multinational Collaborative Study (DIAMOND), and to determine if the incidence rates have increased.

RESEARCH DESIGN AND METHODS

All cases of IDDM diagnosed before the child's 15th birthday between 1 January 1992 and 31 December 1993 were recorded. Prospective notification of all children with newly diagnosed diabetes who were admitted to hospitals and periodic review of hospital medical records provided the primary source; notification by physicians working in diabetic clinics, in which registry of all new cases is mandatory, provided the secondary source of ascertainment.

RESULTS

The degree of ascertainment was 92.2%. The annual incidence of IDDM for children aged 0-14 years over the 2-year period was 15.4/100,000 (95% confidence interval, 12.4-19), with a male:female ratio of 1.2:1. The age-specific annual incidence rates for the age-groups 0-4, 5-9, and 10-14 years were 12.8, 15.1, and 18.3/100,000, respectively, with a male:female ratio of 1.45:1 in the 0- to 4-year-old age-group and an equal sex ratio in the 5- to 9- and 10- to 14-year-old age-groups. No significant difference was detected between incidence rates of IDDM in boys and girls in the three age-groups. There was no significant linear trend toward an increase in IDDM incidence rates as age advanced. Compared with a previous study by Taha et al. (Taha T, Moussa M, Rashed A, Fenech F: Diabetes mellitus in Kuwait: incidence in the first 29 years of life. Diabetologia 25:306-308, 1983), there was a nearly fourfold increase of IDDM in the age-group 0-14 years, mainly in those children < 5 years old, suggesting a rapid increase in a short period of time.

CONCLUSIONS

Kuwait has the highest incidence of IDDM in children in the region, and an apparently increasing incidence has been demonstrated over the last decade.

Paternity after cryptorchidism: lack of correlation with age at orchidopexy

OBJECTIVE

To determine whether paternity is decreased among men who were formerly unilaterally or bilaterally cryptorchid and to ascertain whether paternity is related to their age at orchidopexy.

SUBJECTS AND METHODS

Men who underwent orchidopexy between 1955 and 1969 at the Children's Hospital of Pittsburgh (363) and a group of age-matched control men (336) were surveyed by questionnaire and their medical records reviewed.

RESULTS

Of the married men, significantly more of the unilateral cryptorchid (75%) and control (76%) groups had fathered children than had the bilateral cryptorchid group (P < 0.005). Furthermore, when the groups were compared during the period of regular intercourse with no contraception until conception of their first child, the bilateral group had relatively fewer conceptions during the first year and more after the first year. When the unilateral and bilateral groups were analysed separately, there was no relationship between either age at orchidopexy and paternity or between the age at orchidopexy and the duration of regular unprotected intercourse before conception.

CONCLUSIONS

Compared with a control group, paternity was compromised after bilateral, but not unilateral, cryptorchidism. Age at orchidopexy was not correlated with paternity.

Ascertainment corrected prevalence rate (ACPR) of leukopenia in workers exposed to benzene in small-scale industries calculated with capture-recapture methods

ACPRs of leukopenia in peripheral blood of workers exposed to benzene in small-scale industries are calculated using capture-recapture methods. The results from two figures with 6-month apart demonstrate that the ACPR in workers exposed to benzene is 36.81(29.14-44)%, significantly higher than that of control 12.71(7.20-18.22)% (P < 0.05), with a relative risk of 2.9. The prevalences of 4 cross-sectional investigations in exposure group calculated with routine method are 18.73%, 26.37%, 27.93%, and 36.76% respectively; in controls, 8.38%, 6.85%, 7.94%, and 15.00% respectively and all fall in the range of 95% CI of ACPR. It is suggested that the methods of calculating ACPR by capture-recapture methods is simple, feasible and efficient, with the results more precise than with traditional methods.

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.

Shanghai, China, has the lowest confirmed incidence of childhood diabetes in the world

OBJECTIVE

To determine the incidence of insulin-dependent diabetes mellitus in 0- to 14-year-old children in Shanghai, China, from 1980 to 1991.

RESEARCH DESIGN AND METHODS

Data were collected from hospitals with pediatric departments. The secondary source of validation was primary and middle schools.

RESULTS

The average crude annual incidence rate was 0.61/100,000 (95% confidence interval, 0.48-0.77). The ascertainment-corrected incidence rates were 0.72/100,000 (0.57-0.91).

CONCLUSIONS

The incidence of childhood diabetes in Shanghai, China, was one of the lowest, if not the lowest, in the world.

Association between familial autoimmune diseases and recurrent spontaneous abortions

PROBLEM

To examine the aggregation of autoimmune disease in the families of women experiencing recurrent spontaneous abortions.

METHOD

The 95 participants in this case-control study were recruited from Magee Womens Hospital, Pittsburgh, Pennsylvania from June 1988 to May 1991. The women having recurrent spontaneous abortions (N = 45) reported at least three early fetal losses, and the controls (N = 50) reported a minimum of three pregnancies with at least two live births and no more than one induced or involuntary pregnancy loss. Data from the participants and from their first-degree and second-degree relatives were obtained by questionnaire and verified by a repeated interview, if necessary.

RESULTS

The prevalence of arthritis, thyroid disease, and diabetes mellitus was increased among the relatives of women having recurrent spontaneous abortions compared to normally fertile couples. Several autoimmune diseases occurred concurrently in family members of patients, but not in the family members of normally fertile couples.

CONCLUSIONS

Autoimmune diseases occur more frequently in the families of women who have experienced recurrent spontaneous abortions. Both types of diseases involve genes in the class II region of the major histocompatibility complex.

Approaches to quality control with an application to a new cancer registry in a developing country

Quality control should be maintained in all disease registries by appropriate statistical procedures to assure complete, accurate, reliable, and timely morbidity and mortality data. Shewhart control charts are recommended for evaluating item completeness. Accuracy and reliability can be evaluated with stringent diagnostic criteria, re-abstraction of records, and statistical measures such as the kappa statistic. Discrepancies between observed and expected data in various time periods can be used to evaluate whether data entering a registry meet timeliness criteria. The reporting delay distribution can be used to examine timeliness of reported data and to adjust incidence rates for potential lack of timeliness in reporting. An application of these quality control procedures is demonstrated using two variables selected from a hospital-based study consisting of 119 breast cancer records collected from the Division of Medical Records, Dr Soetomo Hospital, Surabaya, Indonesia. The results indicate that the variable LASTNAME met the selected criteria for completeness and reliability. The variable ADDRESS met the reliability but not the completeness criterion. All reported cases met the timeliness criterion. The demonstration confirmed the need for registries to establish formal quality control procedures.

National diabetes programs. Application of capture-recapture to count diabetes?

OBJECTIVE

To evaluate the utility of capture-recapture methods using multiple, routinely collected, computerized data sources to estimate the numbers and prevalence of diabetes. Methods employed for regional and national monitoring of diabetes have been too inaccurate or too expensive.

RESEARCH DESIGN AND METHODS

A survey was undertaken that used four sources of ascertainment to identify prevalent cases of known diabetes in community of Northern Italy: diabetic clinic and family physicians, hospital discharges, prescriptions, and reagent strips and insulin syringes. Capture-recapture methods were employed to estimate the number of missing cases and to adjust for undercount to accurately estimate the number of people who had diabetes.

RESULTS

We identified 2,069 unique prevalent cases of known diabetes with the intensive case-finding procedure. The diabetic clinic and family physicians data source identified the largest number of cases. The evaluation of the two sample capture-recapture estimates showed that they were all biased downward because of dependencies between sources. Log-linear modeling was employed to take into account the dependence among all data sources and the heterogeneity of diabetic patients. This method estimated that 2,586 cases existed, resulting in an ascertainment-adjusted prevalence of 2.77% (95% confidence interval, 2.44-3.10). Thus, despite the active case identification, approximately 20% could not be identified. However, the number of cases and rates could easily be adjusted using capture-recapture.

CONCLUSIONS

The study shows that a two-sample capture-recapture estimate could be very biased if the investigator is not assured that the sources are independent. However, if at least three data sources are employed, log-linear models allow estimation of the number and prevalence rate adjusted for the degree of undercount (in spite of both the dependence of data sources and the heterogeneity of the diabetic population). The critical factor, however, is that the application of multiple sources with capture-recapture methods could be applied across broad geographical areas and across time to have cost-effective monitoring of diabetes at local and national level.

The role of socioeconomic status and injury morbidity risk in adolescents

OBJECTIVE

To examine the patterns of socioeconomic status and injury morbidity in adolescents.

DESIGN

Prospective cohort study.

SETTING

Metropolitan school district in Allegheny County, Pennsylvania.

PARTICIPANTS

There were 1245 students (89%) recruited from 1400 aged 12 to 16 years.

INTERVENTIONS

None.

MEASURES AND RESULTS

Baseline variables of socioeconomic status used for this analysis included township of residence (from the 1990 census data ranked by the percentage of households below the poverty level) and employment status of the parents (student self-report). Life-table analysis revealed no differential risk of injury by socioeconomic status. Similar results were found when stratified by gender, race, injury type (sport vs nonsport), and injury place (school vs home).

CONCLUSIONS

The results indicate that in this cohort of adolescents, socioeconomic status does not seem to be a contributing risk factor for injury.

The association of physical activity with obesity, fat distribution and glucose intolerance in Pima Indians

The relationships between physical activity, obesity, fat distribution and glucose tolerance were examined in the Pima Indians who have the highest documented incidence of non-insulin-dependent diabetes. Fasting and 2-h post-load plasma glucose concentrations, body mass index, and waist-to-thigh circumference ratios were determined in 1054 subjects aged 15-59 years. Current (during the most recent calendar year) and historical (over a lifetime) leisure and occupational physical activity were determined by questionnaire. Current physical activity was inversely correlated with fasting and 2-h plasma glucose concentrations, body mass index and waist-to-thigh ratios for most sex-age groups even when diabetic subjects were excluded. Controlled for age, obesity and fat distribution, activity remained significantly associated with 2-h plasma glucose concentrations in males. In subjects aged 37-59 years, individuals with diabetes compared to those without reported significantly less leisure physical activity during the teenage years (median hours per week of activity, 9.1 vs 13.2 for men; 1.0 vs 2.2 for women). Controlled for body mass index, sex, age and waist-to-thigh ratio, subjects who reported low levels of historical leisure physical activity had a higher rate of diabetes than those who were more active. In conclusion, current physical activity was inversely related to glucose intolerance, obesity and central distribution of fat, particularly in males. Subjects with diabetes were currently less active and reported less historical physical activity than non-diabetic subjects. These findings suggest that activity may protect against the development of non-insulin-dependent diabetes both directly and through an influence on obesity and fat distribution.

Establishment of accurate incidence rates for head and spinal cord injuries in developing and developed countries: a capture-recapture approach

Prevention of head and spinal cord injuries is defined as a reduction in the incidence of these disabilities. Accurate incidence data are fundamental to any prevention program. The current approaches toward determining incidence rates for head and spinal cord injuries are summarized. Previous research has focused on passive surveillance systems and population-based registries. An alternative system for monitoring the incidence of head injuries is discussed that uses a surveillance methodology called capture-recapture. This method employs multiple population-based sources to identify cases and uses the cases that overlap between the sources to estimate the degree of undercount in the population. This estimate in turn is used to produce an ascertainment-corrected incidence estimate. Through the use of methods such as capture-recapture, accurate monitoring of the incidence of head and spinal injuries across developing and developed countries is indeed feasible.

Should persons with diabetes be licensed to drive trucks?--Risk management

How should a regulatory agency interpret a risk analysis that concludes there is a small increase in risk? The agency must decide on behalf of society whether the increased risk is large enough to justify banning the risky activity or taking some other step to lessen the risks. In a companion paper (Songer et al.), we conclude that licensing insulin using persons to drive commercial motor vehicles in interstate commerce would result in 42 additional crashes each year. Here we address risk management issues by interpreting the number of additional crashes and the relative risks of the prospective handicapped drivers. Are the number of additional crashes (42) significant? Is the increase in the annual crash risk (from 0.00785 to 0.032 for non-insulin dependent and 0.048 for insulin dependent persons) significant? Are the relative risks significant for all insulin using drivers (4.7)? For drivers with a history of severe hypoglycemic reactions (19.8)? How should society tradeoff risk increases for increases in opportunity for these handicapped persons? We review other social decisions concerning highway safety: Accepting the increasing risks of letting 16 year olds drive, allowing extremely light cars, allowing some unsafe highways, and allowing extremely unsafe driving conditions at some times of day. We conclude that the additional risks from insulin using persons are well within the current accepted range of risks.(ABSTRACT TRUNCATED AT 250 WORDS)

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.

The risks of licensing persons with diabetes to drive trucks

The 1990 Americans with Disabilities Act forbids employers to bar disabled persons from jobs unless employers can show the disabled person cannot perform the tasks. The Federal Highway Administration will not license persons with diabetes mellitus to drive commercial motor vehicles in interstate commerce. These individuals may experience severe hypoglycemia, greatly increasing their risk of losing control of the truck. This prohibition is currently being reexamined. We describe the disease process leading to severe hypoglycemia and its physical manifestations. To quantify the risks of licensing persons with diabetes to use insulin, we first estimate the number of potential insulin-using drivers. We estimate that 1420 insulin-using persons would seek licenses in the United States if they were permitted to do so (920 noninsulin dependent and 500 insulin dependent). Next, we estimate the annual incidence of mild and severe hypoglycemia in these populations. The third step is to estimate the number of hypoglycemic episodes while driving. Estimating the likelihood of a crash due to a mild or severe hypoglycemic episode is the fourth step. We estimate that an additional 42 crashes each year would occur if insulin using persons were licensed to drive commercial motor vehicles in interstate commerce (20 from insulin dependent and 22 from non-insulin dependent drivers).