Diabetes, hyperglycaemia and mortality in disabled older women: The Women's Health and Ageing Study I

Relationship of Glycated Hemoglobin A1c with All-Cause and Cardiovascular Mortality among Patients with Hypertension

Both low and high glycated hemoglobin A1c (HbA1c) levels are well-established causal risk factors for all-cause and cardiovascular mortality in the general population and diabetic patients. However, the relationship between HbA1c with all-cause and cardiovascular mortality among patients with hypertension is unclear. We used NHANES data from 1999 to 2014 as the basis for this population-based cohort study. Based on HbA1c levels (HbA1c > 5, HbA1c > 5.5, HbA1c > 6, HbA1c > 6.5, HbA1c > 7%), hypertensive patients were divided into five groups. An analysis of multivariable Cox proportional hazards was conducted based on hazard ratios (HRs) and respective 95% confidence intervals (CIs). The relationship between HbA1c and mortality was further explored using Kaplan–Meier survival curves, restricted cubic spline curves, and subgroup analyses. In addition, 13,508 patients with hypertension (average age 58.55 ± 15.56 years) were included in the present analysis, with 3760 (27.84%) all-cause deaths during a follow-up of 127.69 ± 57.9 months. A U-shaped relationship was found between HbA1c and all-cause and cardiovascular mortality (all p for likelihood ratio tests were 0.0001). The threshold value of HbA1c related to the lowest risk for all-cause and cardiovascular mortality was 5.3% and 5.7%, respectively. Below the threshold value, increased HbA1c levels reduced the risk of all-cause mortality (HR 0.68, 95% CI 0.51–0.90, p = 0.0078) and cardiovascular mortality (HR 0.77, 95% CI 0.57–1.05, p = 0.0969). Inversely, above the threshold value, increased HbA1c levels accelerated the risk of all-cause mortality (HR 1.14, 95% CI 1.11–1.18, p < 0.0001) and cardiovascular mortality (HR 1.22, 95% CI 1.16–1.29, p < 0.0001). In conclusion, A U-shape relationship was observed between HbA1c and all-cause and cardiovascular mortality among hypertensive patients.

Association between timed up and go test and future incidence of disability: A nationwide representative longitudinal study in Korea

Although previous studies examined the association between mobility and disability, they have used either subjective measure disability such as activity of daily living or instrumental activity of daily living or indirect measure such as long-term care service use with small size of participants. This study aimed to examine the association between timed up and go (TUG) test and disability incidence with national disability registration data in Korea longitudinally, by using a national representative sample. We used the National Health Insurance Service–National Health Screening Cohort (NHIS–HEALS) database of National Health Information Database. The NHIS–HEALS dataset includes disability information of National Screening Programme participants, including registration date and type of disability, which is merged from Korean National Disability Registry (KNDR). We used Cox proportional hazard models to evaluate the association between TUG and disability incidence. We constructed three models with different levels of adjustment; Model 3 was a fully adjusted model. We conducted subgroup analysis according to the risk factors for disability. The study population comprised 81,473 participants; 86 of them were newly registered to KNDR, which were observed during a mean follow-up of 4.1 ± 2.6 (maximum, 8.9) years. For 334,200.9 person-year (PY) follow-up, the disability incidence rate was 0.208 per 1,000 PY. Disability incidence was significantly higher in participants with abnormal TUG results than in those with normal TUG results. (adjusted hazard ratio [aHR] 1.600, 95% confidence interval [CI] 1.036–2.472). In subgroup analysis, the disability incidence increased in participants of normal cognition, without obesity or without cardiovascular (CV) disease. Increased incidence in disability was noted in participants with abnormal TUG results. The increase was more evident for participants with normal cognition, without obesity or CV disease.

Association between disability and cardiovascular event and mortality: A nationwide representative longitudinal study in Korea

This study aimed to examine the association between disability and cardiovascular (CV) disease incidence and mortality in Korea longitudinally, using a national representative sample. We used the National Health Insurance Service-National Health Screening Cohort (NHIS-HEALS) database, which includes information on the disability of the National Screening Program participants such as severity and type of disability, which were obtained from the Korean National Disability Registry. Cox proportional hazard models were used to evaluate the association between disability and CV disease incidence and mortality. We constructed four models with different levels of adjustment, in which Model 3 was a fully adjusted model. This study included 514,679 participants, and 7,317 CV deaths were reported within a mean follow up of 10.8 ± 3.9 years (maximum, 13.9 years). For 5,572,130 person-year (PY) follow-up, the CV mortality rate was 1.313 per 1,000 PY. In Models 1 and 2, CV disease incidence was significantly higher in participants with disability than in those without disability. In Model 3, the incidence was higher only among participants aged 50–64 years and severe disabled participants aged <50 years. CV mortality was significantly higher in participants with disability than in those without disability in all Models, and the mortality increased in both sexes in Models 1 and 2 but only increased in men in Model 3. Similar results were observed in the subgroup analysis of health behavior and chronic diseases. People with disability showed higher CV disease incidence and mortality than those without disability, regardless of the type of disability or risk factors for CV disease.

Relationship between HbA1c and all-cause mortality in older patients with insulin-treated type 2 diabetes: results of a large UK Cohort Study

BACKGROUND

our aim was to study the relationship between HbA1c and cardiovascular morbidity and all-cause mortality among older insulin-treated patients with type 2 diabetes (T2D) after adjustment for multiple confounders.

METHODS

data for 4589 adults with T2D (>65 years) on insulin treatment were sourced from 532 UK General Practices via the Health Improvement Network (THIN) database. Cox proportional hazard models and Kaplan-Meier estimators were fitted to derive the hazards of all-cause mortality by HbA1c categories (<6.5, 6.5-7.4, 7.5-8.4, 8.5-9.4, 9.5-10.4, 10.5-11.4%; and 11.5% and above) after 5 years of follow-up following insulin initiation.

RESULTS

we observed a U-shaped relationship between all-cause mortality and HbA1c, with the lowest risk seen in the HbA1c range of 6.5-7.4% and marked increased in risk with HbA1c > 11%. The highest mortality risks of 31 and 40% were significantly associated with the lowest (<6.5%) and highest (11.5% and above) HbA1c categories: aHR: 1.31; (95%CI: 1.10-1.56; P = 0.002) and aHR: 1.40; (95%CI: 1.01-1.96; P = 0.039), respectively.

CONCLUSIONS

both low and high HbA1c were associated with increased all-cause mortality, among older patients with insulin-treated T2D. This cohort study supports the need for individualisation of care and suggests better outcomes with HbA1c levels around 6.5-7.4% and markedly excess risk with HbA1c > 11.

The effect of frailty should be considered in the management plan of older people with Type 2 diabetes

The prevalence of diabetes is increasing especially in older age due to increased life expectancy. In old age, diabetes is associated with high comorbidity burden and increased prevalence of geriatric syndromes including frailty in addition to micro- and macro-vascular complications. The emergence of frailty may change the natural history of Type 2 diabetes from a progressive to a regressive course with increased risk of hypoglycemia. This may result in normalization of blood glucose levels and lead to a state of burnt-out diabetes in frail older people with significant weight loss. Although guidelines suggest relaxed glycemic control in frail elderly with diabetes, complete withdrawal of hypoglycemic medications may be necessary in these frail populations to reduce the risk of hypoglycemia.

Lay abstract: Diabetes is a common disease especially in older people. Aging is associated with reduced appetite and reduced food intake due to lack of exercise and diminished energy consumption. In certain individuals this may be significant leading to weight loss, malnutrition and the development of frailty. As a result the doses of diabetes medications may be too strong for this frail population especially if they have organ dysfunction reducing medication clearance and increasing the risk of low blood glucose level events. Therefore, reduction or complete withdrawal of diabetes medications may be considered in this frail group.

Management of type 2 diabetes in older people

The prevalence of diabetes is increasing due to aging of the population and increasing obesity. In the developed world, there is an epidemiologic shift from diabetes being a disease of middle age to being a disease of older people due to increased life expectancy. In old age, diabetes is associated with high comorbidity burden and increased prevalence of geriatric syndromes in addition to the traditional vascular complications. Therefore, comprehensive geriatric assessment should be performed on initial diagnosis of diabetes. Due to the heterogeneous nature of older people with diabetes and variations in their functional status, comorbidities, and life expectancy, therapeutic interventions, and glycemic targets should be individualized taking into consideration patients' preferences and putting quality of life at the heart of their care plans.

Glycosylated hemoglobin in relationship to cardiovascular outcomes and death in patients with type 2 diabetes: a systematic review and meta-analysis

Background

Chronic hyperglycemia in type 2 diabetes increases the risk of microvascular events. However, there is continuing uncertainty about its effect on macrovascular outcomes and death. We conducted a meta-analysis of prospective studies to estimate the association of glycosylated hemoglobin level with the risk of all-cause mortality and cardiovascular outcomes among patients with type 2 diabetes.

Methodology/Principal Findings

We systematically searched the MEDLINE database through April 2011 by using Medical Subject Heading search terms and a standardized protocol. We included prospective cohort studies that reported data of glycosylated hemoglobin level on the risk of incident cardiovascular events and all-cause mortality. Relative risk estimates (continuous and categorical variables) were derived or abstracted from each cohort study. Twenty six studies were included in this analysis with a mean follow-up rang of 2.2–16 years. The pooled relative risk associated with a 1% increase in glycosylated hemoglobin level among patients with type 2 diabetes was 1.15 (95% CI, 1.11 to 1.20) for all-cause mortality, 1.17 (95% CI, 1.12 to 1.23) for cardiovascular disease, 1.15 (95% CI, 1.10 to 1.20) for coronary heart disease, 1.11 (95% CI, 1.05 to 1.18) for heart failure, 1.11 (95% CI, 1.06 to 1.17) for stroke, and 1.29 (95% CI, 1.18 to 1.40) for peripheral arterial disease, respectively. In addition, a positive dose-response trend existed between glycosylated hemoglobin level and cardiovascular outcomes.

Conclusions/Significance

Chronic hyperglycemia is associated with an increased risk for cardiovascular outcomes and all-cause mortality among patients with type 2 diabetes, likely independently from other conventional risk factors.

Glycemic control, complications, and death in older diabetic patients: the diabetes and aging study

OBJECTIVE

To identify the range of glycemic levels associated with the lowest rates of complications and mortality in older diabetic patients.

RESEARCH DESIGN AND METHODS

We conducted a retrospective cohort study (2004-2008) of 71,092 patients with type 2 diabetes, aged ≥60 years, enrolled in Kaiser Permanente Northern California. We specified Cox proportional hazards models to evaluate the relationships between baseline glycated hemoglobin (A1C) and subsequent outcomes (nonfatal complications [acute metabolic, microvascular, and cardiovascular events] and mortality).

RESULTS

The cohort (aged 71.0 ± 7.4 years [means ± SD]) had a mean A1C of 7.0 ± 1.2%. The risk of any nonfatal complication rose monotonically for levels of A1C >6.0% (e.g., adjusted hazard ratio 1.09 [95% CI 1.02-1.16] for A1C 6.0-6.9% and 1.86 [1.63-2.13] for A1C ≥11.0%). Mortality had a U-shaped relationship with A1C. Compared with the risk with A1C <6.0%, mortality risk was lower for A1C levels between 6.0 and 9.0% (e.g., 0.83 [0.76-0.90] for A1C 7.0-7.9%) and higher at A1C ≥11.0% (1.31 [1.09-1.57]). Risk of any end point (complication or death) became significantly higher at A1C ≥8.0%. Patterns generally were consistent across age-groups (60-69, 70-79, and ≥80 years).

CONCLUSIONS

Observed relationships between A1C and combined end points support setting a target of A1C <8.0% for older patients, with the caution that A1Cs <6.0% were associated with increased mortality risk. Additional research is needed to evaluate the low A1C-mortality relationship, as well as protocols for individualizing diabetes care.

Association of tumor necrosis factor-related apoptosis-inducing ligand with total and cardiovascular mortality in older adults

OBJECTIVE

Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) exhibits biological activity on vascular cells in vitro. Rapid variation of circulating TRAIL levels occurs during acute coronary ischemia, suggesting that biological pathways involving TRAIL may be activated during ischemic heart disease. However, whether differential levels of soluble TRAIL in normal individuals are associated with adverse health outcomes has not been investigated. We tested the hypothesis that TRAIL levels predict mortality in a population based sample of community dwelling men and women.

METHODS

Plasma TRAIL level was measured by ELISA at baseline in 1282 adults (mean age 68 years) enrolled in the InCHIANTI study. Vital status was ascertained over the six-year follow-up.

RESULTS

In multivariable Cox regression analysis adjusted for potential confounders including prevalent cardiovascular diseases (CVD), ankle-brachial index, electrocardiogram abnormalities, and inflammatory markers, baseline TRAIL levels were inversely related to all-cause mortality (p=0.008). In stratified analyses, the prognostic effect of TRAIL level was strong and highly significant in participants with prevalent CVD (N=321), (lowest versus highest quartile: HR 3.1; 95% CI 1.5-6.5) while it was negligible in those free of CVD (p value for the interaction term between CVD status and TRAIL levels=0.038). Similar findings were obtained when CVD mortality was considered as the outcome of interest.

CONCLUSIONS

In older patients with CVD, low levels of TRAIL were associated with increased risk of death over a period of 6 years. Lower concentration of circulating TRAIL may be related to the clinical evolution of older adults with CVD.

Trials review: cardiovascular outcome with intensive glycemic control and implications for patients with type 2 diabetes

Hyperglycemia is associated with microvascular and macrovascular complications. Intensive glucose control has been shown to reduce microvascular complications. Nevertheless, cardiovascular disease remains the leading cause of death in patients with type 2 diabetes. A positive association exists between hemoglobin A1c level and cardiovascular events, but whether reducing blood glucose will reduce cardiovascular events is still not quite clear. The benefits of intensive glucose control also remain uncertain for the heterogenous group of older patients with type 2 diabetes. This article reviews results of earlier and recently published intervention trials of intensive glucose control and their outcomes and discusses relevant recommendations for adults with type 2 diabetes.

Diabetes care among veteran women with disability

OBJECTIVE

The primary objective of this study was to analyze predictors of diabetes care consistent with performance standards among women Veterans Health Administration (VHA) clinic users with disability enrollment status.

METHODS

This is a retrospective cohort study using VHA and Medicare files of VHA clinic users with diabetes. Diabetes care measures consisted of annual testing for hemoglobin A(1c) (HbA(1c)), low-density lipoprotein cholesterol (LDL-C), and poor HbA(1c) (>9%) and LDL-C (> or =130 mg/dL) control in fiscal year 2000. Chi-square tests and logistic regressions were used to assess subgroup differences in diabetes care. Independent variables included demographic characteristics and physical and psychiatric comorbidities.

POPULATION

Study population was based on veteran women <65 years of age who used VHA clinics; we identified 2,344 women as having coexisting disability and diabetes and 2,766 women with diabetes and without disability.

FINDINGS

Among veteran women with diabetes and disability, 65% received > or =1 HbA(1c) test, and 54% received a LDL-C test; 25% and 30% had poor HbA(1c) and LDL-C control, respectively. In logistic regressions, none of the independent variables had significant effects on poor HbA(1c) or LDL-C control, except that African Americans were more likely to have poor HbA(1c) control than whites. Significant age effects were noted in rates of HbA(1c) and LDL testing. Comparison of diabetes care measures between women with and without disability indicated that those with disability were more likely to receive HbA(1c) and LDL-C tests; no significant differences in HbA(1c) and LDL-C control were noted.

CONCLUSIONS

Disability status of women veterans was not a barrier to diabetes care consistent with performance standards. Our findings suggest that to improve diabetes care, subgroup-specific interventions, rather than a global approach, are warranted.

The Effect of Diabetes on Disability in Middle-Aged and Older Adults

BACKGROUND

Physical disability is increasingly recognized as an adverse health consequence of type 2 diabetes in older adults. We studied the effect of diabetes on disability in middle-aged and older adults to: 1) characterize the association of diabetes with physical disability in middle-aged adults, and 2) determine the extent to which the effect of diabetes is explained by related covariates in either or both age groups.

METHODS

We used data from two parallel national panel studies of middle-aged and older adults to study the effect of self-reported diabetes at baseline on disability 2 years later, adjusting for baseline covariates.

RESULTS

Diabetes was strongly associated with subsequent physical disability (measured by a composite variable combining activities of daily living, mobility, and strength tasks) in middle-aged and older adults. Controlling for socioeconomic characteristics and common diabetes-related and unrelated comorbidities and conditions reduced the diabetes effect substantially, but it remained a significant predictor of disability in both groups.

CONCLUSIONS

Our analyses demonstrated that disability is an important diabetes-related health outcome in middle-aged and older adults that should be prevented or mitigated through appropriate diabetes management.