Mortality in African-Americans with Type 1 diabetes: The New Jersey 725

Effect of Body Weight on Glycaemic Indices in People with Type 1 Diabetes Using Continuous Glucose Monitoring

Background/Objectives: Obesity and overweight have become increasingly prevalent in different populations of people with type 1 diabetes (PwT1D). This study aimed to assess the effect of body weight on glycaemic indices in PwT1D. Methods: Adult PwT1D using continuous glucose monitoring (CGM) and followed up at a regional academic diabetes centre were included. Body weight, body mass index (BMI), waist circumference, glycated haemoglobin (HbA1c), and standard CGM glycaemic indices were recorded. Glycaemic indices were compared according to BMI, and correlation and linear regression analysis were performed to estimate the association between measures of adiposity and glycaemic indices. Results: A total of 73 PwT1D were included (48% normal weight, 33% overweight, and 19% obese). HbA1c was 7.2% (5.6-10), glucose management indicator (GMI) 6.9% (5.7-8.9), coefficient of variation (CV) for glucose 39.5% ± 6.4, mean glucose 148 (101-235) mg/dL, TIR (time in range, glucose 70-180 mg/dL) 66% (25-94), TBR70 (time below range, 54-69 mg/dL) 4% (0-16), TBR54 (<54 mg/dL) 1% (0-11), TAR180 (time above range, 181-250 mg/dL) 20% ± 7, and TAR250 (>250 mg/dL) 6% (0-40). Glycaemic indices and achievement (%) of optimal glycaemic targets were similar between normal weight, overweight, and obese patients. BMI was associated negatively with GMI, mean glucose, TAR180, and TAR250 and positively with TIR; waist circumference was negatively associated with TAR250. Conclusions: CGM-derived glycaemic indices were similar in overweight/obese and normal weight PwT1D. Body weight and BMI were positively associated with better glycaemic control. PwT1D should receive appropriate ongoing support to achieve optimal glycaemic targets whilst maintaining a healthy body weight.

Social and Structural Determinants of Cardiovascular Complications of Diabetes

PURPOSE OF REVIEW

Cardiovascular disease (CVD) is the leading cause of mortality in people who have diabetes. Racial and ethnic minorities with diabetes have suboptimal management of cardiovascular risk factors, leading to higher mortality. Social and structural determinants of health are external factors that influence an individual's ability to choose positive health behaviors. In this review, we will discuss cardiovascular complications in people who have diabetes and their relationship to social determinants of health (SDOH).

RECENT FINDINGS

Recent innovations in diabetes treatment, including new devices and medications, have improved care and survival. However, disparities in the availability of these treatments to racial and ethnic minorities may contribute to continued inequities in CVD outcomes. Racial/ethnic disparities in CVD relate to inequities in economic opportunity, education and health literacy, neighborhoods and social cohesion, and health care access and quality driven by structural racism.

Diabetes duration or age at onset and mortality in insulin-dependent diabetics: a systematic review and meta-analysis

BACKGROUND

This meta-analysis was conducted given the contradictory findings from studies on the influence of diabetes duration or age at onset on mortality in patients with insulin-dependent diabetes mellitus (IDDM).

METHODS

Electronic databases (PubMed, Embase, Cochrane, Web of Knowledge, Scopus, and CINHAL) were comprehensively searched to identify relevant studies until October 31, 2022. All of the selected articles contained statistics on hazard ratios, relative risks (RRs), or odds ratios, or data for estimating the association between diabetes duration or age at onset and total mortality in IDDM patients. Regardless the heterogeneity assessed by the I² statistic, pooled RRs and 95% confidence intervals (CI) for total mortality were acquired via random effect meta-analysis with inverse variance weighting.

RESULTS

This meta-analysis finally included 19 studies involving 122, 842 individuals. Both age at onset and diabetes duration were positively associated with an increased mortality rate in IDDM patients. Specifically, the pooled RRs for age at onset and diabetes duration were 1.89 (95%CI 1.43-2.50) and 1.89 (95%CI 1.16-3.09) respectively. Subgroup analyses revealed that only prepubertal onset was associated with a greater survival advantage than pubertal or postpubertal onset.

CONCLUSIONS

The findings of this meta-analysis and systematic review suggest that a later age at onset or longer diabetes duration is associated with increased risk of total mortality in IDDM patients. However, this conclusion shall be interpreted with caution due to the possibility of residual confounding and be confirmed in the future by well-designed studies.

Racial and Ethnic Cardiometabolic Risk Disparities in the Type 1 Diabetes Exchange Clinic Registry Cohort

OBJECTIVE

To determine whether individuals from a historically underrepresented racial group have a higher cardiometabolic risk than historically represented individuals with type 1 diabetes (T1D) considering socioeconomic deprivation.

METHODS

We used the multivariable logistic and linear regression models to examine socioeconomic deprivation (upper 10th percentile) by race/ethnicity interaction for each cardiometabolic risk factor and cardiometabolic risk burden score, respectively, across 6320 zip code tabulation areas. We also determined the age-adjusted prevalence of low, moderate, and high cardiometabolic risks defined as 0, 1 to 2, and 3 or more risk factors for hypertension, obesity, dyslipidemia, and off-target glycemia for non-Hispanic White (n = 15 746), non-Hispanic Black (n = 1019), Hispanic (n = 1115), and other (n = 887), respectively.

RESULTS

The sample comprised 18 767 adolescents and adults with T1D. Those identifying as non-Hispanic Black were more likely to have a high cardiometabolic risk profile, including a 4.5-fold increase in the odds of off-target glycemia, a twofold increase in the odds of systolic hypertension, and 0.29 (unadjusted) and 0.46 (adjusted) increases in a higher cardiometabolic risk burden compared with non-Hispanic White individuals (P < .01). Those identifying as Hispanic had a 3.4-fold increase in the odds of off-target glycemia but were less likely to be overweight/obese or have systolic hypertension compared with non-Hispanic White. However, the lower likelihood of overweight/obesity and hypertension did not persist after considering covariates.

CONCLUSION

There is a need to investigate additional determinants of racially/ethnically underrepresented cardiometabolic health, including structural racism and implicit bias in cardiometabolic care for individuals with T1D.

Highlighting the Role of Obesity and Insulin Resistance in Type 1 Diabetes and Its Associated Cardiometabolic Complications

PURPOSE OF REVIEW

This narrative review appraises research data on the potentially harmful effect of obesity and insulin resistance (IR) co-existence with type 1 diabetes mellitus (T1DM)-related cardiovascular (CVD) complications and evaluates possible therapeutic options.

RECENT FINDINGS

Obesity and IR have increasingly been emerging in patients with T1DM. Genetic, epigenetic factors, and subcutaneous insulin administration are implicated in the pathogenesis of this coexistence. Accumulating evidence implies that the concomitant presence of obesity and IR is an independent predictor of worse CVD outcomes. The prevalence of obesity and IR has increased in patients with T1DM. This increase can be partly attributed to general population trends but, additionally, to iatrogenic weight gain caused by insulin treatment. This association might be the missing link explaining the excess CVD burden observed in patients with T1DM despite optimal glycemic control. Data on newer agents for type 2 diabetes mellitus (T2DM) treatment are unraveling novel ways to challenge this aggravating coexistence.

Long-term complications of type 1 diabetes: what do we know and what do we need to understand?

Long-term complications of type 1 diabetes (T1D) include microvascular complications and macrovascular disease. Despite the important advances in the treatment of T1D of the last decades, these complications still represent the leading cause of morbidity and mortality in patients with T1D. Extensive evidence indicates that structural and functional alterations of the kidney, retina, nerves and large arteries occur already in the first years after the onset of diabetes. We performed a comprehensive review of the available evidence on screening, diagnosis, prevention and treatment of vascular complications of T1D. In particular, we focused on three major challenges related to long-term complications of T1D: 1) finding of new biomarkers and diagnostic methods able to identify early signs of complications; 2) identifying specific risk factors for the development of these complications; 3) identifying and implementing new therapeutic strategies able to prevent the development and progression of vascular complications.

Early mortality and cardiovascular disease, varied association with body mass index and its changes in insulin-treated diabetes: a nationwide study

BACKGROUND/OBJECTIVES

We investigated the hazards of cardiovascular diseases (CVDs) and all-cause death during follow-up according to baseline body mass index (BMI) and percent change in BMI among adults with insulin-treated diabetes.

SUBJECTS/METHODS

Using the Korean National Health Insurance Service datasets (2002-2017), the hazards of myocardial infarction (MI), stroke, and all-cause mortality during follow-up were analyzed according to baseline BMI and percent change in BMI among adults with insulin-treated diabetes and without baseline CVD and/or malignancy (N = 44,055).

RESULTS

At baseline, 67.3% of total subjects were either obese or overweight. During a mean 3.8 years, 1,081 MI and 1,562 stroke cases developed; 2,847 deaths occurred over a mean 3.9 years. Compared with normal weight, overweight and obesity were associated with lower hazards of outcomes [hazard ratio (95% CI): 0.836 (0.712-0.981), 0.794 (0.687-0.917) for MI; 0.829 (0.726-0.946), 0.772 (0.684-0.870) for stroke; 0.740 (0.672-0.816), 0.666 (0.609-0.728) for death, respectively]. Underweight was associated with a higher hazard of all-cause death during follow-up [hazard ratio (95% CI): 2.035 (1.695-2.443)]. When the group with minimum absolute value for percent change in BMI was set as a reference, the relative reduction in BMI was associated with increased hazards of MI, stroke, and all-cause death, and relative increase in BMI was associated with increased hazards of stroke and all-cause death during follow-up.

CONCLUSIONS

Among adults with insulin-treated diabetes, a high prevalence of overweight and obesity was observed, and baseline BMI category was inversely associated with CVD incidence and all-cause death during follow-up. Both weight loss and gain were associated with increased CVD incidence and all-cause death during follow-up, showing a U-shaped relationship between weight change and outcome. Stable body weight might be a predictor of a lower risk of CVDs and premature death among individuals with insulin-treated diabetes.

Diabetic retinopathy predicts cardiovascular mortality in diabetes: a meta-analysis

BACKGROUND

The prognostic significance of diabetic retinopathy (DR) for cardiovascular diseases (CVD) remained unclear. Therefore, we performed this meta-analysis to assess whether DR predicted CVD mortality in diabetic patients.

METHODS

We searched PubMed, Embase, Web of Science and Cochrane Library for cohort studies reporting the association of DR and CVD mortality. Then we pooled the data for analysis.

RESULTS

After screening the literature, 10 eligible studies with 11,239 diabetic subjects were finally included in quantitative synthesis. The pooled risk ratio (RR) of DR, mild DR, and severe DR for CVD mortality was 1.83 (95% confidence interval (CI): 1.42, 2.36; p < 0.001), 1.13 (95% CI 0.81, 1.59; p = 0.46), and 2.26 (1.31, 3.91; p = 0.003), respectively, compared to those without DR. In type 2 DM, the patients with DR had a significantly higher CVD mortality (RR: 1.69; 95% CI 1.27, 2.24; p < 0.001). Subgroup analysis also showed a significantly higher CVD mortality in DR according to various regions, study design, data source, and follow-up period (all RR > 1; all P values < 0.05). Data from 2 studies showed no significant correlation of DR and CVD mortality in diabetic patients receiving cardiovascular surgery (RR: 2.40; 95% CI 0.63, 9.18; P = 0.200).

CONCLUSIONS

DR is a risk marker of cardiovascular death, and severe DR predicts a doubled mortality of CVD in diabetes. These findings indicate the importance of early identification and management of diabetic patients with DR to reduce the risk of death.

Body Mass Index and Mortality in Individuals With Type 1 Diabetes

CONTEXT

The relationship between body mass index (BMI) and mortality may differ between patients with type 1 diabetes and the general population; it is not known which clinical characteristics modify the relationship.

OBJECTIVE

Our aim was to assess the relationship between BMI and mortality and the interaction with clinically meaningful factors.

DESIGN, SETTING, AND PARTICIPANTS

This prospective study included 5836 individuals with type 1 diabetes from the FinnDiane study.

MAIN OUTCOME MEASURE AND METHODS

We retrieved death data for all participants on 31 December 2015. We estimated the effect of BMI on the risk of mortality using a Cox proportional hazards model with BMI as a restricted cubic spline as well as effect modification by adding interaction terms to the spline.

RESULTS

During a median of 13.7 years, 876 individuals died. The relationship between baseline BMI and all-cause mortality was reverse J-shaped. When analyses were restricted to those with normal albumin excretion rate, the relationship was U-shaped. The nadir BMI (BMI with the lowest mortality) was in the normal weight region (24.3 to 24.8 kg/m2); however, among individuals with diabetic nephropathy, the nadir BMI was in the overweight region (25.9 to 26.1 kg/m2). Diabetic nephropathy, diabetes-onset age, and sex modified the relationship between BMI and mortality (Pinteraction < 0.05).

CONCLUSIONS

Normal weight is optimal for individuals with type 1 diabetes to delay mortality, whereas underweight might be an indication of underlying complications. Maintaining normal weight may translate into reduced risk of mortality in type 1 diabetes, particularly for individuals of male sex, later diabetes-onset age, and normal albumin excretion rate.

BMI, Mortality, and Cardiovascular Outcomes in Type 1 Diabetes: Findings Against an Obesity Paradox

OBJECTIVE

Low weight has been associated with increased mortality risks in type 1 diabetes. We aimed to investigate the importance of weight and weight gain/loss in the Swedish population diagnosed with type 1 diabetes.

RESEARCH DESIGN AND METHODS

Patients with type 1 diabetes (n = 26,125; mean age 33.3 years; 45% women) registered in the Swedish National Diabetes Registry from 1998 to 2012 were followed from the first day of study entry. Cox regression was used to calculate risk of death from cardiovascular disease (CVD), major CVD events, hospitalizations for heart failure (HF), and total deaths.

RESULTS

Population mean BMI in patients with type 1 diabetes increased from 24.7 to 25.7 kg/m² from 1998 to 2012. Over a median follow-up of 10.9 years, there were 1,031 deaths (33.2% from CVD), 1,460 major CVD events, and 580 hospitalizations for HF. After exclusion of smokers, patients with poor metabolic control, and patients with a short follow-up time, there was no increased risk for mortality in those with BMI <25 kg/m², while BMI >25 kg/m² was associated with a minor increase in risk of mortality, major CVD, and HF. In women, associations with BMI were largely absent. Weight gain implied an increased risk of mortality and HF, while weight loss was not associated with higher risk.

CONCLUSIONS

Risk of major CVD, HF, CVD death, and mortality increased with increasing BMI, with associations more apparent in men than in women. After exclusion of factors associated with reverse causality, there was no evidence of an obesity paradox.

Late adulthood mortality among African-American and white American people with Type 1 diabetes according to age at diabetes diagnosis

AIMS

To estimate the overall and cause-specific mortality in a population of African-Americans and white Americans with a low socio-economic status who had young-onset insulin-treated diabetes and had survived beyond the age of 40 years, and to examine whether any excess risk varied according to age at diabetes onset.

METHODS

Using the Southern Community Cohort Study, we conducted a mortality follow-up of a cohort of mostly low-income participants aged 40-79 years (mean 50 years) at cohort entry with insulin-treated diabetes diagnosed before age 30 years (n=475) and without diabetes (n=62 266). Childhood onset was defined as diabetes diagnosed before age 20 years (n=162), while young-adulthood onset was defined as diabetes diagnosed between ages 20 and 29 years (n=313). Cause-specific mortality was based on both underlying and contributing causes of death, obtained from death certificates. Multivariable Cox analysis was performed.

RESULTS

During follow-up (mean 9.5 years), 38.7% of those with and 12.9% of those without diabetes died. Compared with those without diabetes, increases in mortality rate were generally similar among those with childhood- and young-adulthood-onset diabetes for deaths from: all causes (childhood: hazard ratio 4.3, CI 3.3-5.5; young adulthood: hazard ratio 4.9, CI 4.0-5.8); ischaemic heart disease (childhood: hazard ratio 5.7, CI 3.5-9.4; young adulthood: hazard ratio 7.9, CI 5.6-11.0); heart failure (childhood: hazard ratio 7.3, CI 4.2-12.7; young adulthood: hazard ratio 5.4, CI 3.3-8.9); sepsis (childhood: hazard ratio 10.3, CI 6.1-17.3; young adulthood: hazard ratio 8.8, CI 5.7-13.5); renal failure (childhood: hazard ratio 15.1, CI 8.6-26.5; young adulthood: hazard ratio 18.2, CI 12.3-27.1); respiratory disorders (childhood: hazard ratio 3.9, CI 2.3-6.7; young adulthood: hazard ratio 5.3, CI 3.7-7.7); suicide/homicide/accidents (childhood: hazard ratio 2.3, CI 0.72-7.0; young adulthood: hazard ratio 5.8, CI 3.4-10.2); and cancer (childhood: hazard ratio 2.1, CI 0.98-4.4; young adulthood: hazard ratio 1.2, CI 0.55-2.5).

CONCLUSIONS

We observed high excess long-term mortality for all-cause, renal failure, ischemic heart disease and heart failure mortality in African-American and white American people with early-onset insulin-treated diabetes.

Intensive Diabetes Treatment and Cardiovascular Outcomes in Type 1 Diabetes Mellitus: Implications of the Diabetes Control and Complications Trial/Epidemiology of Diabetes Interventions and Complications Study 30-Year Follow-up

Type 1 diabetes mellitus, an autoimmune disorder characterized by beta-cell destruction and absolute insulin deficiency, is associated with significantly increased cardiovascular disease risk but the mechanisms underlying this enhanced risk are unclear. Results of the pivotal Diabetes Control and Complications Trial/Epidemiology of Diabetes Interventions and Complications study have shown that compared to conventional therapy, intensive glycemic control results in decreased cardiovascular morbidity and mortality. Evidence from this study also revealed contributions of blood pressure, renal disease, body weight, and lipids to cardiovascular disease in type 1 diabetes mellitus. Extrapolating from existing evidence, this article addresses clinical strategies to mitigate cardiovascular risks.

Risk stratification for 25-year cardiovascular disease incidence in type 1 diabetes: Tree-structured survival analysis of the Pittsburgh Epidemiology of Diabetes Complications study

BACKGROUND

The formal identification of subgroups with varying levels of risk is uncommon in observational studies of cardiovascular disease, although such insight might be useful for clinical management.

METHODS

Tree-structured survival analysis was utilized to determine whether there are meaningful subgroups at varying levels of cardiovascular disease risk in the Pittsburgh Epidemiology of Diabetes Complications study, a prospective cohort study of childhood-onset (<17 years old) type 1 diabetes.

RESULTS

Of the 561 participants free of cardiovascular disease (coronary artery disease, stroke or lower extremity arterial disease) at baseline, 263 (46.9%) had an incident cardiovascular disease event over the 25-year follow-up. Tree-structured survival analysis revealed a range of risk groups, from 24% to 85%, which demonstrate that those with short diabetes duration and elevated non-high-density lipoprotein cholesterol have similar cardiovascular disease risk to those with long diabetes duration and that renal disease is a better discriminator of risk in men than in women.

CONCLUSION

Our findings suggest that subgroups with major cardiovascular disease risk differences exist in this type 1 diabetes cohort. Using tree-structured survival analysis may help to identify these groups and the interrelationships between their associated risk factors. This approach may improve our understanding of various clinical pathways to cardiovascular disease and help target intervention strategies.

Plasma markers of inflammation and prediction of cardiovascular disease and mortality in African Americans with type 1 diabetes

BACKGROUND

To determine whether plasma levels of markers of inflammation are predictive of the incidence of cardiovascular disease (CVD), hypertension, or mortality in African Americans with type 1 diabetes mellitus.

METHODS

A total of 484 African Americans with type 1 diabetes were included. At baseline and 6-year follow-up, a clinical interview and examination were conducted to document CVD and systemic hypertension. Venous blood for glycated hemoglobin and cholesterol was obtained and albumin excretion rate measured. Mortality was assessed annually between baseline and 6-year follow-up by review of the social security death index. Baseline plasma levels of 28 inflammatory biomarkers were measured using multiplex bead analysis system.

RESULTS

After adjusting for baseline age and other confounders, African Americans with type 1 diabetes in the highest quartile of plasma interferon-inducible protein 10 (IP-10) were three times more likely to develop CVD than those in the lowest quartile. African Americans with type 1 diabetes in the lowest quartiles of plasma stromal derived factor-1 (SDF-1) had a 75% higher risk of death than patients in the highest quartile, independently of age, low density lipoprotein cholesterol, body mass index, hypertension, and albuminuria.

CONCLUSION

In African Americans with type 1 diabetes, high plasma IP-10 is an independent predictor for incident CVD and low SDF-1 an independent predictor for mortality.

Risk of all-cause mortality and vascular events in women versus men with type 1 diabetes: a systematic review and meta-analysis

BACKGROUND

Studies have suggested sex differences in the mortality rate associated with type 1 diabetes. We did a meta-analysis to provide reliable estimates of any sex differences in the effect of type 1 diabetes on risk of all-cause mortality and cause-specific outcomes.

METHODS

We systematically searched PubMed for studies published between Jan 1, 1966, and Nov 26, 2014. Selected studies reported sex-specific estimates of the standardised mortality ratio (SMR) or hazard ratios associated with type 1 diabetes, either for all-cause mortality or cause-specific outcomes. We used random effects meta-analyses with inverse variance weighting to obtain sex-specific SMRs and their pooled ratio (women to men) for all-cause mortality, for mortality from cardiovascular disease, renal disease, cancer, the combined outcome of accident and suicide, and from incident coronary heart disease and stroke associated with type 1 diabetes.

FINDINGS

Data from 26 studies including 214 114 individuals and 15 273 events were included. The pooled women-to-men ratio of the SMR for all-cause mortality was 1·37 (95% CI 1·21-1·56), for incident stroke 1·37 (1·03-1·81), for fatal renal disease 1·44 (1·02-2·05), and for fatal cardiovascular diseases 1·86 (1·62-2·15). For incident coronary heart disease the sex difference was more extreme; the pooled women-to-men ratio of the SMR was 2·54 (95% CI 1·80-3·60). No evidence suggested a sex difference for mortality associated with type 1 diabetes from cancer, or accident and suicide.

INTERPRETATION

Women with type 1 diabetes have a roughly 40% greater excess risk of all-cause mortality, and twice the excess risk of fatal and nonfatal vascular events, compared with men with type 1 diabetes.

FUNDING

None.

All-cause mortality in a population-based type 1 diabetes cohort in the U.S. Virgin Islands

OBJECTIVE

Type 1 diabetes remains a significant source of premature mortality; however, its burden has not been assessed in the U.S. Virgin Islands (USVI). As such, the objective of this study was to estimate type 1 diabetes mortality in a population-based registry sample in the USVI.

RESEARCH DESIGN AND METHODS

We report overall and 20-year mortality in the USVI Childhood (<19 years old) Diabetes Registry Cohort diagnosed 1979-2005. Recent data for non-Hispanic blacks from the Allegheny County, PA population-based type 1 diabetes registry were used to compare mortality in the USVI to the contiguous U.S.

RESULTS

As of December 31, 2010, the vital status of 94 of 103 total cases was confirmed (91.3%) with mean diabetes duration 16.8 ± 7.0 years. No deaths were observed in the 2000-2005 cohort. The overall mortality rates for those diagnosed 1979-1989 and 1990-1999 were 1852 and 782 per 100,000 person-years, respectively. Overall cumulative survival for USVI was 98% (95% CI: 97-99) at 10 years, 92% (95% CI: 89-95) at 15 years and 73% (95% CI: 66-80) at 20 years. The overall SMR for non-Hispanic blacks in the USVI was 5.8 (95% CI: 2.7-8.8). Overall mortality and cumulative survival for non-Hispanic blacks did not differ between the USVI and Allegheny County, PA.

CONCLUSIONS

This study, as the first type 1 diabetes mortality follow-up in the USVI, confirmed previous findings of poor disease outcomes in racial/ethnic minorities with type 1 diabetes.

Mortality by race among low-income adults with early-onset insulin-treated diabetes

OBJECTIVE

To determine if long-term mortality rates in early-onset insulin-treated diabetes differ by race among adults of similar socioeconomic status.

RESEARCH DESIGN AND METHODS

A total of 391 (299 African Americans, 92 whites) mostly low-income adults 40-79 years of age with insulin-treated diabetes diagnosed before 30 years of age were recruited from community health centers in the southeast U.S. Cox models were used to estimate hazard ratios (HRs) of all-cause mortality among African Americans compared with whites. Additionally, standardized mortality ratios (SMRs) were used to compare the mortality experience of the individuals with diabetes with both national and general community health center sex- and race-specific population norms.

RESULTS

Mean age at diabetes diagnosis and cohort entry, respectively, was 21 and 50 years in African Americans and 19 and 51 years in whites. During an average of 6.7 years of follow-up, 29% of African Americans and 35% of whites died. In multivariable analysis, no significant mortality difference was observed among African Americans compared with whites (HR 0.83 [95% CI 0.53-1.30]; P=0.51). Compared with the race-specific U.S. general population, SMRs for those with diabetes were 5.7 in African Americans and 11.7 in whites. However, when compared with the same source population (i.e., the community health center population), SMRs were 3.5 and 3.7 in African Americans and whites, respectively.

CONCLUSIONS

Elevated mortality persists in men and women with long duration of early-onset insulin-treated diabetes, but given survival to 40 years of age and similarly low economic status and access to health care, our data do not suggest a racial disparity in mortality.

The impacts of albuminuria and low eGFR on the risk of cardiovascular death, all-cause mortality, and renal events in diabetic patients: meta-analysis

BACKGROUND

Precise effects of albuminuria and low estimated glomerular filtration rate (eGFR) on cardiovascular mortality, all-cause mortality, and renal events in diabetic patients are uncertain.

MATERIALS AND METHODS

A systematic review was conducted of the literature through MEDLINE, EMBASE, and CINHAL from 1950 to December 2010. Cohort studies of diabetic patients providing adjusted relative risk (RR) of albuminuria and eGFR for risks of cardiovascular mortality, all-cause mortality, and renal events were selected. Two reviewers screened abstracts and full papers of each study using standardized protocol.

RESULTS

We identified 31 studies fulfilling the criteria from 6546 abstracts. With regard to the risk of cardiovascular mortality, microalbuminuria (RR 1.76, 95%CI 1.38-2.25) and macroalbuminuria (RR 2.96 95%CI 2.44-3.60) were significant risk factors compared to normoalbuminuria. The same trends were seen in microalbuminuria (RR 1.60, 95%CI 1.42-1.81), and macroalbuminuria (RR 2.64, 95%CI 2.13-3.27) for the risk of all-cause mortality, and also in microalbuminuria (RR 3.21, 95%CI 2.05-5.02) and macroalbuminuria (RR 11.63, 95%CI 5.68-23.83) for the risk of renal events. The magnitudes of relative risks associated with low eGFR along with albuminuria were almost equal to multiplying each risk rate of low eGFR and albuminuria. No significant factors were found by investigating potential sources of heterogeneity using subgroup analysis.

CONCLUSIONS

High albuminuria and low eGFR are relevant risk factors in diabetic patients. Albuminuria and low eGFR may be independent of each other. To evaluate the effects of low eGFR, intervention, or race, appropriately designed studies are needed.

Medical and psychological risk factors for incident hypertension in type 1 diabetic african-americans

Objective. To determine risk factors for the development of hypertension among African-Americans living with type 1 diabetes. Methods. African-Americans with type 1 diabetes (n = 483) participated in a 6-year followup. At both baseline and followup blood pressure was measured twice in both sitting and standing positions using a standard protocol. Patients had a structured clinical interview, ocular examination, retinal photographs, and blood and urine assays and completed the Hostility and Direction of Hostility Questionnaire (HDHQ) and the Beck Depression Inventory (BDI). Results. Of the 280 diabetic patients with no hypertension at baseline, 82 (29.3%) subsequently developed hypertension over the 6-year followup. Baseline older age, longer duration of diabetes, family history of hypertension, greater mean arterial blood pressure, overt proteinuria, increasing retinopathy severity, peripheral neuropathy, smoking, and higher hostility scores were significantly associated with the development of hypertension. Multivariate analyses showed that higher hostility scores and overt proteinuria were significantly and independently associated with the development of hypertension in this population. Conclusions. The development of hypertension in African-Americans living with type 1 diabetes appears to be multifactorial and includes both medical (overt proteinuria) as well as psychological (high hostility) risk factors.

All-cause mortality trends in a large population-based cohort with long-standing childhood-onset type 1 diabetes: the Allegheny County type 1 diabetes registry

OBJECTIVE

Although management of type 1 diabetes improved dramatically in the 1980s, the effect on mortality is not clear.

RESEARCH DESIGN AND METHODS

We report trends in 30-year mortality using the Allegheny County (Pennsylvania) childhood-onset (age <18 years) type 1 diabetes registry (n = 1,075) with diagnosis from 1965-1979, by dividing the cohort into three diagnosis year cohorts (1965-1969, 1970-1974, and 1975-1979). Local (Allegheny County) mortality data were used to calculate standardized mortality ratios (SMRs).

RESULTS

As of 1 January 2008, vital status was ascertained for 97.0% of participants (n = 1,043) when mean age ± SD and duration of diabetes were 42.8 ± 8.0 and 32.0 ± 7.6 years, respectively. The 279 deaths (26.0%) observed were 7 times higher than expected (SMR 6.9 [95% CI 6.1-7.7]). An improving trend in SMR was seen by diagnosis cohort at 30 years of diabetes duration (9.3 [7.2-11.3], 7.5 [5.8-9.2], and 5.6 [4.0-7.2] for 1965-1969, 1970-1974, and 1975-1979, respectively). Although no sex difference in survival was observed (P = 0.27), female diabetic patients were 13 times more likely to die than age-matched women in the general population (SMR 13.2 [10.7-15.7]), much higher than the SMR for men (5.0 [4.0-6.0]). Conversely, whereas 30-year survival was significantly lower in African Americans than in Caucasians (57.2 vs. 82.7%, respectively; P < 0.001), no differences in SMR were seen by race.

CONCLUSIONS

Although survival has clearly improved, those with diabetes diagnosed most recently (1975-1979) still had a mortality rate 5.6 times higher than that seen in the general population, revealing a continuing need for improvements in treatment and care, particularly for women and African Americans with type 1 diabetes.

Cause-specific mortality trends in a large population-based cohort with long-standing childhood-onset type 1 diabetes

OBJECTIVE

Little is known concerning the primary cause(s) of mortality in type 1 diabetes responsible for the excess mortality seen in this population.

RESEARCH DESIGN AND METHODS

The Allegheny County (Pennsylvania) childhood-onset (age < 18 years) type 1 diabetes registry (n = 1,075) with diagnosis from 1965 to 1979 was used to explore patterns in cause-specific mortality. Cause of death was determined by a mortality classification committee of at least three physician epidemiologists, based on the death certificate and additional records surrounding the death.

RESULTS

Vital status for 1,043 (97%) participants was ascertained as of 1 January 2008, revealing 279 (26.0%) deaths overall (141 females and 138 males). Within the first 10 years after diagnosis, the leading cause of death was acute diabetes complications (73.6%), while during the next 10 years, deaths were nearly evenly attributed to acute (15%), cardiovascular (22%), renal (20%), or infectious (18%) causes. After 20 years' duration, chronic diabetes complications (cardiovascular, renal, or infectious) accounted for >70% of all deaths, with cardiovascular disease as the leading cause of death (40%). Women (P < 0.05) and African Americans (P < 0.001) have significantly higher diabetes-related mortality rates than men and Caucasians, respectively. Standardized mortality ratios (SMRs) for non-diabetes-related causes do not significantly differ from the general population (violent deaths: SMR 1.2, 95% CI 0.6-1.8; cancer: SMR 1.2, 0.5-2.0).

CONCLUSIONS

The excess mortality seen in type 1 diabetes is almost entirely related to diabetes and its comorbidities but varies by duration of diabetes and particularly affects women and African Americans.

The geoepidemiology of type 1 diabetes

Type 1 diabetes (T1D) is a chronic autoimmune disease characterized by absolute insulin deficiency resulting from the progressive immune-mediated destruction of pancreatic islet beta cells. It is thought to be triggered by as yet unidentified environmental factors in genetically susceptible individuals, the major genetic contribution coming from loci within the HLA complex, in particular HLA class II. The worldwide incidence of T1D varies by at least 100-fold, being highest in Finland and Sardinia (Italy) and lowest in Venezuela and China. The incidence has been increasing worldwide at an annual rate of approximately 3%. While genetic factors are thought to explain some of the geographic variability in T1D occurrence, they cannot account for its rapidly increasing frequency. Instead, the declining proportion of newly diagnosed children with high-risk genotypes suggests that environmental pressures are now able to trigger T1D in genotypes that previously would not have developed the disease during childhood. Although comparisons between countries and regions with low and high-incidence rates have suggested that higher socioeconomic status and degree of urbanization are among the environmental factors that play a role in the rising incidence of T1D, the findings are too inconsistent to allow firm conclusions. Morbidity and mortality as well as causes of death also show considerable geographic variation. While glycemic control has been identified as a major predictor of the micro- and macrovascular complications of T1D and shows considerable geographical variability, it does not appear to be the only factor involved in the regional differences in complication rates. The role of genetics in susceptibility to nephropathy, retinopathy and other diabetic complications largely remains to be explored.

Adiposity and mortality in type 1 diabetes

BACKGROUND

In the general population, adiposity exhibits a J- or U-shaped relationship with mortality; however, in catabolic states this relationship is often inversely linear. We have recently documented an age-independent increase in overweight/obesity in the Pittsburgh Epidemiology of Diabetes Complications Study (EDC) of type 1 diabetes (T1D). As intensified insulin therapy (IIT) may promote weight gain, the impact of weight gain in T1D is of importance. We therefore assessed the association of adiposity with mortality in 655 EDC participants during 20 years of follow-up.

METHODS

Individuals were categorized as underweight (body mass index (BMI)<20), normal (20< or = BMI <25), overweight (25< or = BMI <30), or obese (BMI > or =30). Cox models were constructed using BMI and covariates at baseline, updated means during follow-up, time variation (reflecting most recent status), and change during adulthood as predictors of mortality.

RESULTS

The prevalence of IIT (3+ insulin shots daily and/or pump) increased from 7 to 82%. Overweight increased by 47% and obesity increased sevenfold. There were 146 deaths. In unadjusted models, BMI (modeled continuously) showed a quadratic relationship with mortality (P=0.002, <0.0001 <0.0001 for baseline, updated mean and time-varying models, respectively). However, only in the time-varying model were the obese significantly different from the normal weight, whereas the baseline model showed no differences by BMI category. In both the updated mean and time-varying models, the underweight were at greater risk than were the normal weight (P<0.0001 both models). The nonlinear relationship of adiposity with mortality remained after adjustment for diabetes complications and for biological or socioeconomic/lifestyle risk factors, with the exception of baseline socioeconomic/lifestyle risk factors, in which a linear association emerged. Adjustment for waist circumference eliminated risk in the obese. Finally, weight gain during follow-up was protective.

CONCLUSION

The relationship of adiposity with mortality in T1D now seems to resemble that of the general population, albeit with a marked increased risk in those who are underweight.

Proliferative retinopathy and proteinuria predict mortality rate in type 1 diabetic patients from Fyn County, Denmark

AIMS/HYPOTHESIS

We evaluated the effect of diabetic retinopathy on 25 year survival rate among a population-based cohort of type 1 diabetic patients from Fyn County, Denmark.

METHODS

In 1973 all diabetic patients from Fyn County, Denmark with onset before the age of 30 years as of 1 July 1973 were identified (n=727). In 1981, only 627 patients were still alive and resident in Denmark. Of these, 573 (91%) participated in a clinical baseline examination, in which diabetic retinopathy was graded and other markers of diabetes measured. Mortality rate was examined in a 25 year follow-up and related to the baseline examination.

RESULTS

Of the 573 patients examined at baseline in 1981 and 1982, 297 (51.8%) were still alive in November 2006. Of the others, 256 (44.7%) had died, three (0.5%) had left Denmark and 17 (3%) were of unknown status. Age- and sex-adjusted HRs of mortality rate were 1.01 (95% CI 0.72-1.42) and 2.04 (1.43-2.91) for patients with non-proliferative and proliferative retinopathy respectively at baseline compared with patients with no retinopathy. After adjusting for proteinuria, HR among patients with proliferative retinopathy lost statistical significance, but still remained 1.48 (95% CI 0.98-2.23). The 10 year survival rate of patients who had proliferative retinopathy as well as proteinuria at baseline was 22.2% and significantly lower (p<0.001) than in patients with proteinuria only (70.3%), proliferative retinopathy only (79.0%) or neither (86.6%).

CONCLUSIONS/INTERPRETATION

Proliferative retinopathy and proteinuria predict mortality rate in a population-based cohort of type 1 diabetic patients. In combination they act even more strongly. Non-proliferative diabetic retinopathy did not affect survival rate.

Risk factors for mortality in a diverse cohort of patients with childhood-onset diabetes in Chicago

OBJECTIVE

We sought to determine whether risk of death differed by demographic or other characteristics in a population-based cohort of patients with childhood-onset diabetes.

RESEARCH DESIGN AND METHODS

The Chicago Childhood Diabetes Registry is an ethnically diverse cohort of patients with diabetes onset between ages 0 and 17 years. Cases that accumulated from 1 January 1985 to 31 December 2000 (n = 1,238) were assessed for vital status using death certificates, family reports, and two large administrative databases (Social Security Death Index and National Death Index). Mortality was compared between subgroups using Poisson and Cox proportional hazards regression.

RESULTS

Thirty subjects died, with a mean follow-up time of 7.75 years, yielding a crude case fatality rate of 2.4%. Six subjects died of diabetic ketoacidosis (DKA) at initial presentation. Onset age was the predominant risk factor, driven by a substantially higher fatality rate among those diagnosed at age 17 years (13.36/1,000 person-years) than among other ages and by moderately higher rates for those diagnosed in early adolescence (ages 10-13 years) (3.49/1,000 person-years), compared with children diagnosed before age 10 years (0.89/1,000 person-years) or at ages 14-16 years (0.81/1,000 person-years). Mortality did not differ significantly by other factors examined; data for whites were insufficient to allow comparisons with that group. In addition to diabetes, frequent causes of death were trauma, infectious disease, and cardiovascular disease.

CONCLUSIONS

This study provides short- to medium-term follow-up in a diverse cohort of patients. DKA remains a significant cause of death in young people with diabetes. Young people diagnosed at the threshold of adulthood are at increased risk for mortality.

Six-year incidence of proteinuria in type 1 diabetic African Americans

OBJECTIVE

We sought to report the 6-year incidence of proteinuria and associated risk factors in African Americans with type 1 diabetes.

RESEARCH DESIGN AND METHODS

African Americans (n = 483) with type 1 diabetes were reexamined in a 6-year follow-up study. Proteinuria and creatinuria were measured in 4-h timed urine specimens obtained at initial and follow-up visits. Other evaluations included a structured clinical interview, ocular examination, masked grading of seven stereoscopic fundus photographs, blood pressure measurements, blood assays, and administration of the Beck Depression Inventory (BDI).

RESULTS

Over the 6-year period, 117 (42.9%) of the 473 patients at risk developed "any" proteinuria, defined as either microalbuminuria (26.0%) or overt (16.9%) proteinuria; 87 (23.5%) progressed from micro- or no albuminuria to overt proteinuria and 39 (8.7%) to end-stage renal disease; and 40 (20.6%) regressed. Peak incidence of any proteinuria occurred for patients who were 10-14 years of age or had 5-10 years of diabetes duration at baseline. Multiple regression analysis showed that baseline albumin excretion rate (AER), systemic hypertension, blood cholesterol, and high BDI depression scores were significant and independent risk factors for incidence of any proteinuria.

CONCLUSIONS

In African Americans with type 1 diabetes, the 6-year incidence of proteinuria is high, particularly among young patients and those with a relatively short duration of diabetes at baseline. Baseline AER is the strongest predictor for incidence of any proteinuria.