Prevalence of complications in IDDM by sex and duration. Pittsburgh Epidemiology of Diabetes Complications Study II.

The prevalence of and interrelationships among all four major complications of insulin-dependent diabetes mellitus (IDDM) and their risk factors are being examined in a large epidemiologic study of IDDM subjects diagnosed in childhood. This article focuses on the baseline prevalence of complications in the 657 subjects diagnosed between 1950 and 1980 and currently aged 8-48 yr, with a mean duration of 20 yr. In addition to background retinopathy being virtually universal after 20 yr of diabetes, proliferative retinopathy affects 70% of IDDM subjects after 30 yr duration. As with overt nephropathy, prevalence of proliferative retinopathy is marginally higher in females than in males at short durations; the previously reported male excess is limited to the subjects with IDDM of longer duration (greater than or equal to 25 yr). Somewhat different patterns of microalbuminuria are also seen by sex. Males show a threefold increase in prevalence from 10 to 25 yr duration, whereas females show a more constant prevalence across these durations. A further rise in microalbuminuria is seen in males but not females at greater than or equal to 30 yr duration, giving a combined prevalence of microalbuminuria and overt nephropathy at greater than or equal to 30 yr duration of 84% (males) and 59% (females). Distal symmetrical polyneuropathy shows a constant rise with duration and is only marginally higher in men. Prevalence of cardiovascular (coronary and cerebral) disease shows no sex difference, whereas peripheral vascular disease is particularly common in women after 30 yr duration (greater than 30%) compared with men (11%) when determined by ankle/arm blood pressure ratio less than 0.8 at rest or after exercise.(ABSTRACT TRUNCATED AT 250 WORDS)

Menopause in type 1 diabetic women: is it premature?

Women with type 1 diabetes have a delayed menarche and a greater prevalence of menstrual disorders than women without diabetes. However, little is known about the menopause transition among type 1 diabetic women. The Familial Autoimmune and Diabetes (FAD) Study recruited both adult individuals who were identified from the Children's Hospital of Pittsburgh Type 1 Diabetes Registry for the years 1950-1964 and their family members. Unrelated nondiabetic control probands and their relatives were also evaluated. Women with type 1 diabetes (n = 143) compared with nondiabetic sisters (n = 186) or unrelated control subjects (n = 160) were more likely to have an older age at menarche (13.5, 12.5, and 12.6 years, respectively, P < 0.001), more menstrual irregularities before 30 years of age (45.7, 33.3, and 33.1%, respectively, P = 0.04), and a younger age at menopause (41.6, 49.9, and 48.0 years, respectively, P = 0.05). This resulted in a 6-year reduction in the number of reproductive years (30.0, 37.0, and 35.2 years, respectively, P = 0.05) for women with type 1 diabetes. Risk factors univariately associated with earlier menopause included type 1 diabetes (hazard ratio [HR] 1.99, P = 0.04), menstrual irregularities before 30 years of age (HR 1.87, P = 0.04), nulliparity (HR 2.14, P = 0.01), and unilateral oophorectomy (HR 6.51, P < 0.0001). Multivariate analysis confirmed that type 1 diabetes (HR 1.98, P = 0.056), menstrual irregularities by 30 years of age (HR 2.36, P = 0.01), and unilateral oophorectomy (HR 9.76, P < 0.0001) were independent determinants of earlier menopause in our cohort. We hypothesize that an earlier menopause, which resulted in a 17% decrease in reproductive years, is a major unstudied complication of type 1 diabetes.

The Pittsburgh insulin-dependent diabetes mellitus (IDDM) morbidity and mortality study. Mortality results.

A follow-up study of 1966 patients with insulin-dependent diabetes mellitus (IDDM) who were diagnosed at Children's Hospital of Pittsburgh (CHP) between 1950 and 1981 has been completed. The mean age of the population at follow-up was 21.2 yr with a mean duration of IDDM of 12.9 yr. Nine percent of the patients were deceased, a sevenfold excess in mortality compared with the U.S. population. The relative increase in mortality was greater for females than males and greater for blacks than whites. Before age 20, the primary excess in mortality was at onset of IDDM, or within 6 mo after onset, and was due to acute diabetic complications. After age 20, the annual mortality risk was approximately 2%, which was more than 20 times greater than for the U.S. population. Renal disease was responsible for the majority of these deaths. There was a reduced risk of dying for diabetic patients who were diagnosed between 1966 and 1971 compared with patients diagnosed during earlier years.

Epidemiological correlates of diabetic neuropathy. Report from Pittsburgh Epidemiology of Diabetes Complications Study.

The natural history of diabetic neuropathy and its risk factors are not well understood, apart from the recognition that prevalence increases with duration and, in many studies, degree of glycemia. The role of potential risk factors was therefore evaluated in a cross-sectional analysis from the baseline examination of the Pittsburgh Epidemiology of Diabetes Complications Study. We present results from the first 400 subjects seen at baseline examination. Neuropathy was determined by a trained internist with a standardized examination and was defined as the presence of at least two of three criteria: abnormal sensory or motor signs, symptoms consistent with neuropathy, and decreased tendon reflexes. The prevalence of neuropathy in this cohort was 34% (18%, 18-29 yr old, 58% greater than or equal to 30 yr old) with no difference by sex. By focusing on subjects greater than or equal to 18 yr old, all significant univariate variables (e.g., duration, glycosylated hemoglobin [HbA1]) were analyzed in 3 multiple logistic regression models: all subjects greater than or equal to 18 yr old and separating the same subjects into two groups based on age (18-29 and greater than or equal to 30 yr). Duration, HbA1, smoking status, and high-density lipoprotein cholesterol were found to be associated with neuropathy in the models for the greater than or equal to 18-yr-old group and the greater than or equal to 30-yr-old group. In the 18- to 29-yr-old group, duration, HbA1, and hypertension status were found to be significantly associated with neuropathy.(ABSTRACT TRUNCATED AT 250 WORDS)

Immunogenetics of insulin-dependent diabetes mellitus in humans.

Diabetes mellitus is the second most prevalent chronic disease in children in the U.S. It is associated with severe manifestations which include blindness and circulation deficiencies as well as markedly increased risk of death. The etiology of diabetes mellitus remains a mystery although both genetic and environmental factors have been implicated. The geneticist is confronted with a number of obstacles in his attempts to unravel this problem, including differences in the definition of affected individuals. This matter was certainly clarified by the separation of noninsulin-dependent diabetes (NIDDM) and insulin-dependent diabetes mellitus (IDDM) into two separate disease entities. Twin studies, however, show that IDDM cannot be entirely due to genetic causes as concordance is no more than about 50%. Although the disease is then clearly not inherited per se, the "susceptibility" to diabetes seems almost surely inherited and, provided this susceptibility, the disease can be brought on by environmental factors. Until the underlying mechanism causing IDDM is completely ascertained, we have to rely on genetic markers to approach the study of the inheritance thereof. Since, in the early 1970s, research by Nerup's and Cudworth's groups revealed associations between the HLA-B locus and IDDM, the HLA markers are considered the classical genetic markers for IDDM susceptibility. In this paper, we review the nature of the genetic susceptibility to IDDM and the possible environmental factors which can bring on the disease.

Diabetic autonomic neuropathy and cardiovascular risk. Pittsburgh Epidemiology of Diabetes Complications Study III.

Diabetic autonomic neuropathy (DAN) has been shown to confer a high risk of mortality. The association between DAN and cardiovascular risk factors was examined in a well-defined cohort of 25- to 34-year-old insulin-dependent diabetes mellitus subjects (n = 168) with and without DAN as evaluated by heart rate response to deep breathing, standing, and the Valsalva maneuver. The autonomic tests were performed using both an office-based procedure and a method employed by the Diabetes Control and Complications Trial with analyses performed by the Diabetes Research and Analysis Association, Lexington, Ky. Good agreement was found between the procedures for the assessment modalities of heart rate response to deep breathing. Modeling potential correlates in logistic analyses, where heart rate response to deep breathing was the dependent variable, revealed hypertension status, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, and gender (female) to be independent determinants of DAN. These results suggest that traditional cardiovascular risk factors are important correlates of DAN and may relate to both its cause and poor prognosis. Since these results are from a cross-sectional study, prospective follow-up of this cohort will be needed for confirmation.

A cold spot of IDDM incidence in Europe. Macedonia.

OBJECTIVE: To determine, for the first time, the incidence of IDDM among children 0-15 yr of age in Macedonia, the south republic of former Yugoslavia, and to compare these rates with those from neighboring countries. RESEARCH DESIGN AND METHODS: Children < 15 yr of age, with IDDM diagnosed between January 1985 and December 1991, were registered using the criteria established for the WHO Multinational Project for Childhood Diabetes. The primary source of case ascertainment consisted of clinical records from the University Pediatric Clinic in Skopje, the capital of Macedonia. The secondary source consisted of records for insulin supplies from the pharmacy in Skopje and from 15 local hospitals. RESULTS: During 1985-1991, 112 children < 15 yr of age were diagnosed with IDDM in Macedonia. The completeness of case ascertainment was 96.6%. The age-adjusted IDDM incidence rate was very low, only 2.45/100,000 per yr. No significant sex difference in incidence was observed. The highest incidence rate occurred in the 10- to 15-yr age-group. No temporal trends were observed. CONCLUSIONS: The incidence of IDDM in Macedonia is the lowest in Europe and among the lowest reported for Caucasian populations. However, the descriptive epidemiology is similar to that for high incidence populations. Further etiological studies are required to evaluate potential reasons for the very low incidence of IDDM in Macedonia.

Mortality trends in type 1 diabetes. The Allegheny County (Pennsylvania) Registry 1965-1999.

OBJECTIVES: To investigate long-term mortality and its temporal trends as of 1 January 1999 among the 1,075 patients with type 1 diabetes (onset age <18 years, diagnosed between 1965 and 1979) who comprise the Allegheny County population-based registry. RESEARCH DESIGN AND METHODS: Overall, sex- and race-specific mortality rates per person-year of follow-up were determined. Standardized mortality ratios were also calculated. Survival analyses and Cox proportional hazard model were also used. Temporal trends were examined by dividing the cohort into three groups by year of diagnosis (1965-1969, 1970-1974, and 1975-1979). RESULTS: Living status of 972 cases was ascertained as of January 1, 1999 (ascertainment rate 90.4%). The mean duration of diabetes was 25.2 +/- 5.8 (SD) years. Overall, 170 deaths were observed. The crude mortality rate was 627 per 100,000 person-years (95% CI 532-728) and standardized mortality ratio was 519 (440-602). Life-table analyses by the Kaplan-Meier method indicated cumulative survival rates of 98.0% at 10 years, 92.1% at 20 years, and 79.6% at 30 years duration of diabetes. There was a significant improvement in the survival rate between the cohort diagnosed during 1965-1969 and that diagnosed during 1975-1979 by the log-rank test (P = 0.03). Mortality was higher in African-Americans than in Caucasians, but there were no differences seen by sex. The improvement in recent years was seen in both ethnic groups and sexes. CONCLUSIONS: An improvement in long-term survival was observed in the more recently diagnosed cohort. This improvement is consistent with the introduction of HbA1 testing, home blood glucose monitoring, and improved blood pressure therapy in the 1980s.

Health insurance and the financial impact of IDDM in families with a child with IDDM.

OBJECTIVE: To examine the health insurance experience and out-of-pocket health care costs of families with a child with IDDM. RESEARCH DESIGN AND METHODS: A case-control study of 197 families with a child with IDDM and 142 control families with no diabetic children was conducted. IDDM-affected families were identified from the Allegheny County IDDM Registry. Brothers and sisters of the parents in the IDDM-affected families were asked to participate as control subjects. Health insurance coverage and the money that families spent on health care services and supplies not reimbursed by insurance (out-of-pocket costs) were assessed by questionnaire. RESULTS: No difference was found between the IDDM-affected and control families in the percentages with or without insurance. Families with low household incomes ($10,000-$19,999) were at the greatest risk for having no insurance. While coverage provided by private plans was similar between the IDDM-affected and control families, many families had no reimbursement for insulin (10%), syringes (10%), or blood testing strips (30%). Out-of-pocket expenses were 56% higher in the IDDM-affected families than in the control families. Seventeen percent of the IDDM-affected families had expenses over 10% of their household income. This particularly affected families with low household incomes. Pre-existing illness clauses and insurance denial affected only a small proportion of the case families. CONCLUSIONS: These data illustrate that most families with a child with IDDM have health insurance, yet still incur larger out-of-pocket health care costs than do families without the presence of diabetes. IDDM-affected families likely face a number of economic decisions regarding health insurance and the use of health care.

Was there an epidemic of diabetes in nonwhite adolescents in Allegheny County, Pennsylvania?

OBJECTIVE: To determine the incidence of IDDM in children aged < 20 years at diagnosis in Allegheny County, Pennsylvania, for the period from 1 January 1990 to 31 December 1994 and to compare the incidence between whites and nonwhites in the same area and for the same time period. RESEARCH DESIGN AND METHODS: All new patients diagnosed between January 1990 and December 1994 who were aged < 20 years, on insulin, and residents of Allegheny County at diagnosis were identified from medical records of 23 hospitals in the Allegheny County area. To verify the completeness of the hospitals using the capture-recapture method, pediatricians and diabetologists were used as a secondary source. RESULTS: A total number of 257 patients were identified. The overall age-standardized incidence rate was 16.7/100,000. Nonwhites had a slightly higher incidence (17.6/100,000) than whites (16.5/100,000). In the 15-19 years age-group, the incidence in nonwhites (30.4/100,000) was almost three times higher than that in white (11.2/100,000) and more than two times higher than that in the previous period (from 1985 to 1989) (13.8/100,000). CONCLUSIONS: For the first time in the Allegheny County registry, and in any other registry, nonwhites showed a higher incidence of IDDM than whites. The high incidence in the 15-19 years age-group was responsible for this phenomenon. This epidemic of diabetes in adolescent nonwhites may be the result of a rising incidence of classical IDDM or another type of diabetes. Further studies using population-based registries are needed to determine whether this increase is being seen in other areas and other ethnic groups and to clarify the reasons for the increase in IDDM among blacks.

Islet cell autoimmunity in white and black children and adolescents with IDDM.

OBJECTIVE: To compare the frequency of islet cell antibodies (ICA) and antibodies to GAD65 and IA-2(ICA512) between black and white children and adolescents at the diagnosis of IDDM in a large consecutive series of cases from Children's Hospital of Pittsburgh. RESEARCH DESIGN AND METHODS: ICA and antibodies to GAD65 and IA-2 were measured in 437 white and black children and adolescents who were diagnosed with IDDM at < 19 years of age at Children's Hospital of Pittsburgh from January 1983 to December 1985, from January to December 1989, and from January 1996 to December 1997. RESULTS: The prevalence of ICA(H), GAD65, and IA-2 antibodies was significantly lower in blacks than whites at onset of the disease. In contrast, the prevalence of ICA(R) alone was higher in blacks. None of the antibodies were present in 12% of the blacks compared with 4% in whites. The same pattern was seen in both sexes. The prevalence of antibodies in white patients with onset of IDDM at <11 years of age was no different than in those who developed IDDM during adolescence. In contrast, black patients showed a significantly lower prevalence of almost all antibodies in the adolescent group. CONCLUSIONS: Black adolescents were more likely to not have antibodies, suggesting either that they have a nonautoimmune type of diabetes or that antibodies are not being detected by these assays.

Cyclosporin therapy for prevention and cure of IDDM. Epidemiological perspective of benefits and risks.

Cyclosporin and other immunosuppressive agents have been proposed as a preventive treatment against the development of insulin-dependent diabetes mellitus (IDDM) in relatives at increased risk for the disease, based on the understanding that its etiology is an ongoing process of autoimmune beta-cell destruction. We used an epidemiological approach to evaluate several recent trials of cyclosporin in newly diagnosed IDDM patients to determine the degree of benefit that is to be expected. We assessed these and other studies to estimate the potential adverse effects of such treatment, were it to be used in the future, either in newly diagnosed subjects or healthy high-risk relatives. Standard sample-size calculations were used to quantify the number of study subjects necessary to allow adequate statistical power to test the positive and negative effects of a future treatment (alpha = 0.05, beta = 0.20). The estimates were based on the data available from published studies of cyclosporin treatment. The importance of conducting an adequate trial of such a therapy, both from an ethical and a practical viewpoint, is discussed. Five small immunosuppression trials were evaluated. Remission rates in treated subjects exceeded those in control subjects by 15-59%. Variability in defining remission may account for the differences in rates across the studies. Estimates of the major beneficial and adverse effects of cyclosporin were derived from these trials and studies of patients who have undergone long-term immunosuppression. Indicators of kidney damage associated with cyclosporin treatment were reported in 5-47% of treated subjects.(ABSTRACT TRUNCATED AT 250 WORDS)

Health, life, and automobile insurance characteristics in adults with IDDM.

OBJECTIVE: To determine whether people with insulin-dependent diabetes mellitus (IDDM) were compromised in their access to insurance. RESEARCH DESIGN AND METHODS: A case-control study of 158 people with IDDM and 158 nondiabetic siblings matched for age and sex was conducted to evaluate the health, life, and automobile insurance characteristics and history of people with IDDM. RESULTS: Health insurance coverage (yes/no) among the IDDM and sibling control subjects was similar. More than 90% of the IDDM and control respondents had insurance through a private third-party source, and this insurance did not differ by type of plan, coverage, or premium. However, Medicare coverage was more common among the IDDM subjects and was associated with the presence of severe diabetic complications. IDDM subjects were also more likely to have been denied a health insurance policy by an insurer than were the control subjects (23 vs. 1%, P less than 0.001). Similarly, there was no difference between the IDDM and sibling control subjects in the number who had a life or automobile insurance policy. However, life and automobile insurance refusal was much more frequent among the IDDM respondents, more so for life (55 vs. 0%, P less than 0.001) than for automobile (12 vs. 4%, P less than 0.05) insurance. CONCLUSIONS: These results suggest that access to insurance is severely compromised for people with IDDM. Although most of those with IDDM are able to find some form of insurance, it is evident that on average they must go to extra lengths to find it. These data and a changing insurance environment emphasize the need to reexamine, as a society, the importance of insurance for people with chronic disease, particularly IDDM.

Motor vehicle accidents and IDDM.

A case-control study examining the 1-yr motor vehicle accident experiences of 158 insulin-dependent diabetes mellitus (IDDM) cases and 158 nondiabetic siblings was undertaken to evaluate the risk of motor vehicle accidents among drivers with IDDM. In multivariate analyses the overall accident risk of the cases and control subjects did not differ significantly. Female diabetic drivers, however, showed a marked increased risk for motor vehicle accidents. The accident risk among female cases was five times higher than among the female control subjects (P less than .05). Age and marital status were also significantly associated with accident probability in the multivariate model. The results suggest that IDDM could have an effect on the accident rate of diabetic drivers, particularly women. However, the traditional risk factors for automobile accidents, i.e., age and marital status, appear to have an equally strong influence on accident occurrence. Further studies are needed to 1) document the role of IDDM in accidents among representative samples of the IDDM population and 2) properly evaluate the licensing restrictions recommended for diabetic drivers.

The Pittsburgh Insulin-Dependent Diabetes Mellitus (IDDM) Morbidity and Mortality Study: case-control analyses of risk factors for mortality.

Although children with IDDM are at a sevenfold increased risk of dying when compared with nondiabetic individuals of the same age, the factors associated with the excess in mortality remain unclear. To investigate potential determinants of mortality among IDDM patients, a case-control study was conducted. These retrospectively obtained data indicated that shorter relative height at onset, frequent diabetes-related readmissions, the presence of diabetes complications, a family history of diabetes, premature familial mortality, no participation in school team sports, and a lower level of education were related to subsequent mortality among males. Among females, however, a shorter duration of diabetes clinic attendance and the presence of diabetes complications were the only significant associations to mortality.

Measuring diabetic neuropathy. Assessment and comparison of clinical examination and quantitative sensory testing.

The need for a standardized and valid means of assessing diabetic neuropathy has been increasingly recognized. To identify potential components of such an assessment, interobserver variation (neurologist and internist) of a standard neurologic examination and the comparability of this examination with vibratory and thermal sensitivity testing was studied. The study population comprised the first 100 participants in a neuropathy substudy of 25- to 34-yr-old subjects with insulin-dependent diabetes mellitus taking part in a cohort follow-up study. Symptoms of dysesthesias, paresthesias, and burning, aching, or stabbing pain revealed good interobserver agreement. Signs of neuropathy, more prevalent in the great toe than index finger, showed poor interobserver agreement for vibration, but fair interobserver agreement for touch and pinprick. Mean quantitative sensory thresholds differed significantly by clinical category of abnormal vibratory and pinprick sensations. Threshold testing showed twice the prevalence of abnormality compared with clinical examination. It is concluded that components of the clinical examination can be identified that, along with quantitative sensory-threshold testing, may provide a satisfactory core assessment for use both in epidemiologic studies and incorporation into more in-depth protocols required for clinical research and practice. The clinical relevance of the greater prevalence of abnormalities on threshold testing will be established by long-term follow-up.

Factors associated with avoidance of severe complications after 25 yr of IDDM. Pittsburgh Epidemiology of Diabetes Complications Study I.

To identify characteristics associated with long-term avoidance of insulin-dependent diabetes mellitus (IDDM) complications, subjects taking part in an epidemiologic natural history study of childhood-onset IDDM, with a duration of disease greater than or equal to 25 yr, were studied. Nineteen percent of 175 subjects had avoided overt nephropathy, definite cardiovascular and peripheral vascular disease, clinical neuropathy, and proliferative retinopathy. Approximately half of the nonrenal complications occurred in the absence of renal disease. Subjects free of these advanced complications were characterized by a longer duration of disease (P less than 0.05), better lipid profile and blood pressure (P less than 0.01), and considerably lower glycosylated hemoglobin levels (P less than 0.001). Health-related behaviors, including recent medical contact, regular glucose monitoring, physical activity in youth, and avoidance of cigarette smoking, did not relate to complication status, although regular (at least weekly) alcohol consumption was more prevalent (P less than 0.05) in those without complications. We conclude that a lower mean glycosylated hemoglobin level is strongly related to the avoidance of all IDDM complications.

Early infant diet and risk of IDDM in blacks and whites. A matched case-control study.

OBJECTIVE: To investigate the role of early infant feeding in the development of insulin-dependent diabetes mellitus (IDDM) and to determine whether an association exists in both blacks and whites. RESEARCH DESIGN AND METHODS: Black and white diabetic subjects were recruited from the Allegheny County and Children's Hospital of Pittsburgh IDDM Registries. Extensive infant diet histories were obtained from the diabetic subjects and their nondiabetic siblings, who were used as nondiabetic control subjects. Each diabetic subject was matched outside his/her family to an unrelated nondiabetic control subject on birth order, birth year (+/- 2 yr), and race, which resulted in 211 case-control pairs with a mean birth year of 1967. RESULTS: In whites, diabetic subjects were less likely to have been breast-fed than control subjects (odds ratio [OR] 0.5, 95% confidence interval [CI] 0.3, 0.9). Breast-feeding prevalence did not differ between black diabetic subjects and control subjects. Duration of overall and exclusive breast-feeding did not differ between diabetic and control subjects in the black and white cohorts. The following analyses, which examined whether the timing of the first breast milk substitute to which the infant was exposed differed between diabetic and control subjects, were conducted for exposure to any breast milk substitute and to breast milk substitutes that were cow's milk based. In whites, age at exposure to any breast milk substitutes and cow's milk-based substitutes were similar between diabetic and control subjects. In blacks, the first exposure to breast milk substitutes occurred significantly earlier for any substitute (5.1 vs. 11.9 wk, P = 0.02) and marginally earlier for cow's milk-based substitutes (3.9 vs. 8.5 wk, P = 0.07) in diabetic subjects compared with control subjects. The first exposure to breast milk substitutes was more likely to occur by 3 mo of age in black diabetic subjects compared with black control subjects (OR 3.3, 95% CI 1.1-10.0) after adjusting for maternal age at birth. The addition of breast-feeding status to the model only slightly weakened this association in blacks. CONCLUSIONS: The analyses of this study cohort suggest that the observed protective effect of breast-feeding on the risk of IDDM may be related to differences in the age at exposure to breast milk substitutes in blacks but not in whites.

Employment spectrum of IDDM.

Occupational issues in 158 insulin-dependent diabetes mellitus (IDDM) individuals and 158 matched nondiabetic siblings were examined in a case-control design to evaluate the role of diabetes in the employability of people with IDDM. Overall, the IDDM cases were more likely to report refusal for a job at some point in their lives (56 vs. 42%, P = .02) than were the nondiabetic control siblings. Surprisingly, individuals who told job interviewers about their diabetes were more likely to report job refusal than their siblings (64 vs. 42%, P = .005), whereas individuals who did not mention their diabetes reported rates of refusal similar to their siblings (44 vs. 41%). IDDM cases were also less likely to be employed full time compared with siblings (55 vs. 73%, P = .001). Reduced employment in IDDM respondents was related to work disability. Reported work disability was more than seven times greater in the IDDM than the sibling group. The presence of diabetic complications was the primary factor related to work disability. Although 13% of IDDM respondents were unable to work because of disability, absenteeism among IDDM cases currently working did not differ from that of the nondiabetic siblings. Diabetes was not significantly associated with career levels or household income levels reported by the IDDM group. Disability, however, had a strong detrimental influence on these variables. The results suggest that hiring practices by employers may still be discriminatory toward individuals with IDDM. Once hired, the employment experiences of the IDDM population appear to be similar to the experiences of the nondiabetic population, provided the development of disabling diabetic complications has not taken place.

Assessment of AlbuSure and its usefulness in identifying IDDM subjects at increased risk for developing clinical diabetic nephropathy.

This study, which included 154 participants in a 10-yr follow-up study of diabetes complications, was conducted to evaluate AlbuSure (a qualitative test designed to detect urinary albumin concentrations greater than 0.03 g/L) for its ability to discriminate between albumin concentrations above and below the manufacturer's concentration threshold and to identify individuals at increased risk for developing diabetic nephropathy (i.e., those with albumin excretion rate [AER] greater than 0.0288 g/24 h). The reproducibility of AlbuSure results was also evaluated. The results of these evaluations were examined by three different types of urine collections (24 h, overnight, and timed postclinic) and overall. AlbuSure's validity was examined by comparing its results to immunonephelometrically measured concentrations and AER. When compared to albumin concentration, AlbuSure had an overall sensitivity of 81.8%, specificity of 94.8%, and positive predictive value of 90.6%. AlbuSure's sensitivity was lower (71.4%) when compared with AER; however, this was higher than the sensitivity achieved by dipsticks against AER (50.7%). On testing urine samples stored for 3 days at 4 degrees C, AlbuSure results were 100% reproducible after 1 day and had an overall reproducibility of 92% after 3 days. When urine was retested after 3 and 15 mo of storage at -70 degrees C, AlbuSure was greater than or equal to 90% reproducible, with some of the differing results attributable to corresponding changes in albumin concentration. The overnight sample appeared to be the sample of choice for testing with AlbuSure in that it showed excellent reproducibility and the highest sensitivity (compared to both albumin concentration and AER).