Relationship between HbA(1)c and mortality in a Japanese population

Association between time in range and cancer mortality among patients with type 2 diabetes: a prospective cohort study

Background:

Little was known about the association among time in range (TIR), time above range (TAR), time below range (TBR), and cancer mortality among patients with type 2 diabetes. We aimed to investigate the association among TIR, TAR, TBR, and the risk of cancer mortality among patients with type 2 diabetes.

Methods:

A total of 6225 patients with type 2 diabetes were prospectively recruited in Shanghai, China. TIR was measured with continuous glucose monitoring at baseline and was defined as the average percentage of time in the target glucose range during a 24 h period. Cox proportion hazard regression analysis was used to determine the association between TIR and the risk of cancer mortality.

Results:

During a mean follow-up of 7.10 years, we confirmed 237 death events related to cancer. The multivariable-adjusted hazard ratio (HR) for cancer mortality was 1.32 (95% confidence interval [CI]: 1.01–1.75) in patients with TIR ≤70% compared with those with TIR >70%. When TIR was considered as a continuous variable, the multivariable-adjusted HR for cancer mortality associated with each 10% decrease in TIR was 1.07 (95% CI: 1.02–1.14). In the site-specific analysis, a significant association between TIR as a continuous variable and the risk of hepatocellular cancer was found (HR: 1.24; 95% CI: 1.09–1.41). However, no relationship between hemoglobin A1c and cancer mortality was observed (HR: 1.04; 95% CI: 0.97–1.10).

Conclusions:

The present study found an inverse association of TIR with the risk of cancer mortality among patients with type 2 diabetes. New evidence of TIR was added into the clinical practice that TIR may be an optimal target of glycemic control among patients with type 2 diabetes.

A Combination of Blood Pressure and Total Cholesterol Increases the Lifetime Risk of Coronary Heart Disease Mortality: EPOCH-JAPAN

AIM

Lifetime risk (LTR) indicates the absolute risk of disease during the remainder of an individual's lifetime. We aimed to assess the LTRs for coronary heart disease (CHD) mortality associated with blood pressure (BP) and total cholesterol levels in an Asian population using a meta-analysis of individual participant data because no previous studies have assessed this risk.

METHODS

We analyzed data from 105,432 Japanese participants in 13 cohorts. Apart from grade 1 and 2-3 hypertension groups, we defined "normal BP" as systolic/diastolic BP ＜130/＜80 mmHg and "high BP" as 130-139/80-89 mmHg. The sex-specific LTR was estimated while considering the competing risk of death.

RESULTS

During the mean follow-up period of 15 years (1,553,735 person-years), 889 CHD deaths were recorded. The 10-year risk of CHD mortality at index age 35 years was ≤ 0.11%, but the corresponding LTR was ≥ 1.84%. The LTR of CHD at index age 35 years steeply increased with an increase in BP of participants with high total cholesterol levels [≥ 5.7 mmol/L (220 mg/dL)]. This risk was 7.73%/5.77% (95% confidence interval: 3.53%-10.28%/3.83%-7.25%) in men/women with grade 2-3 hypertension and high total cholesterol levels. In normal and high BP groups, the absolute differences in LTRs between the low and high total cholesterol groups were ≤ 0.25% in men and ≤ 0.40% in women.

CONCLUSIONS

High total cholesterol levels contributed to an elevated LTR of CHD mortality in hypertensive individuals. These findings could help guide high-risk young individuals toward initiating lifestyle changes or treatments.

Antihypertensive treatment and risk of cardiovascular mortality in patients with chronic kidney disease diagnosed based on the presence of proteinuria and renal function: A large longitudinal study in Japan

Several recent clinical trials and meta-analyses have shown that lowering blood pressure reduces the risk of cardiovascular disease. However, current evidence that describes general demographics in blood pressure and mortality with chronic kidney disease is sparse in Japan. Using a population-based longitudinal cohort that received annual health checkups in Japan in 2008, hypertensive status, self-reported use of antihypertensive drugs, and prognosis were examined through 2012. Chronic kidney disease was defined as positive proteinuria or estimated glomerular filtration rate <60 ml/min/1.73 m². Subjects were 40 to 74 years old (n = 227,204) with median 3.6 years follow-up period, and patients with and without chronic kidney disease were analyzed separately (n = 183,586 and n = 43,618, respectively). Cardiovascular disease mortality, comprising coronary heart diseases and stroke as entered in the national death registry using ICD-10 coding, was examined. Among all subjects, 346 deaths (96 in chronic kidney disease and 250 in non-chronic kidney disease) due to cardiovascular disease occurred. Compared with cardiovascular disease mortality in chronic kidney disease patients with untreated normal blood pressure, the multivariable adjusted hazard ratio was 3.08 (95% confidence interval: 1.75–5.41) for those with untreated hypertension, 2.30 (1.31–4.03) for those who became normotensive after treatment, and 3.28 (1.91–5.64) for those who remained hypertensive despite treatment. In non-chronic kidney disease subjects, the ratios were 1.90 (1.33–5.41), 1.95 (1.35–2.80), and 1.77 (1.18–2.66), respectively. These results from a nationwide cohort could be one of representative demographics of controlling blood pressure and cardiovascular disease deaths when treating patients with chronic kidney disease in Japan in recent years. Even after development and spread of anti-hypertensive drugs, preventing development of hypertension is preferable, because any hypertension treatment status comparing untreated normal blood pressure was a risk of cardiovascular mortality at baseline year.

Cardiovascular risk and blood pressure lowering treatment among elderly individuals: Evidence for Cardiovascular Prevention from Observational Cohorts in Japan

OBJECTIVE

There is little evidence to support an increased risk of blood pressure (BP) elevation among elderly individuals receiving antihypertensive drug treatment.

METHODS

To clarify the impact on BP level and residual cardiovascular risk in treated elderly individuals, we analysed individual participant data of 26 133 residents aged 60-89 years from seven Japanese general populations and cross-classified participants by age category, 60-74 (young-old) versus 75-89 years (old-old), and by usage of antihypertensive medication at baseline survey (1980-1995).

RESULTS

During a median follow-up period of 12.7 years, 2451 cardiovascular deaths were observed. Multivariable-adjusted hazard ratios of cardiovascular mortality in treated participants compared with untreated participants were 1.30 [95% confidence intervals, 1.16-1.46) and 1.35 (95% confidence interval, 1.16-1.56) in young-old and old-old participants, respectively. Irrespective of antihypertensive medication, the risk increase of total cardiovascular and stroke mortality with elevation of BP was significant among young-old (P ≤ 0.0013), but not significant among old-old participants (P ≥ 0.061).

CONCLUSION

Although impact on BP was more evident among young-old than old-old individuals, clinicians who prescribe antihypertensive medication to elderly patients should consider that such patients require further monitoring.

Lifetime Risk of Stroke and Coronary Heart Disease Deaths According to Blood Pressure Level

Lifetime risk (LTR) provides an absolute risk assessment during the remainder of one’s life. Few studies have focused on the LTRs of stroke and coronary heart disease (CHD), categorized by fine blood pressure in Asian populations. We aimed to assess it using a large database of a meta-analysis with the individual participant data. The present meta-analysis included 107 737 Japanese (42.4% men; mean age, 55.1 years) from 13 cohorts. During the mean follow-up of 15.2±5.3 years (1 559 136 person-years), 1922 died from stroke and 913 from CHD. We estimated risks after adjusting for competing risk of death other than the outcome of interest. The 10-year risk of stroke and CHD deaths at index age of 35 years was ≤1.9% and ≤0.3%, respectively. The LTRs of stroke death at the index age of 35 years (men/women) were 6.1%/4.8% for optimal, 5.7%/6.3% for normal, and 6.6%/6.0% for high-normal blood pressure groups, and 9.1%/7.9% for grade 1, 14.5%/10.3% for grade 2, and 14.6%/14.3% for grade 3 hypertension groups. The LTRs of CHD death similarly elevated with an increase in blood pressure but were lower (≤7.2%) than those of stroke death. In conclusion, blood pressure was clearly associated with an elevated LTR of stroke or CHD death, although the LTR of CHD death was one-half of that of stroke death in an Asian population. These results would help young people with hypertension to adopt a healthy lifestyle or start antihypertensive therapy early.

Age-specific impact of diabetes mellitus on the risk of cardiovascular mortality: An overview from the evidence for Cardiovascular Prevention from Observational Cohorts in the Japan Research Group (EPOCH-JAPAN)

Background

Diabetes mellitus is a strong risk factor for cardiovascular disease. However, the age-specific association of diabetes with cardiovascular risk, especially in the elderly, remains unclear in non-Western populations.

Methods

A pooled analysis was conducted using 8 cohort studies (mean follow-up period, 10.3 years) in Japan, combining the data from 38,854 individual participants without history of cardiovascular disease. In all, 1867 of the participants had diabetes, defined based on the 1998 World Health Organization criteria. The association between diabetes and the risk of death from cardiovascular disease, coronary heart disease (CHD), and stroke was estimated using a stratified Cox model, accounting for variability of baseline hazard functions among cohorts.

Results

During the follow-up, 1376 subjects died of cardiovascular disease (including 268 of coronary heart disease and 621 of stroke). Diabetes was associated with an increased risk of cardiovascular death after multivariable adjustment (hazard ratio [HR] 1.62; 95% confidence interval [CI], 1.35–1.94). Similarly, diabetes was a risk factor for CHD (HR 2.13; 95% CI, 1.47–3.09) and stroke (HR 1.40; 95% CI, 1.05–1.85). In the age-stratified analysis of the risk of cardiovascular death, the relative effects of diabetes were consistent across age groups (p for heterogeneity = 0.18), whereas the excess absolute risks of diabetes were greater in participants in their 70s and 80s than in younger subjects.

Conclusions

The management of diabetes is important to reduce the risk of death from cardiovascular disease, not only in midlife but also in late life, in the Japanese population.

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We conducted meta-analysis of individual data from 8 Japanese cohorts (n = 38,854).

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Diabetes raised cardiovascular mortality in Japan.

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Impact of diabetes on cardiovascular death was similar across 10-year age groups.

Distribution of Glycated Haemoglobin According to Early-Life and Contemporary Characteristics in Adolescents and Adults without Diabetes: The 1982 and 1993 Pelotas Birth Cohorts

Aim

Glycated haemoglobin (HbA_1c), a marker of glucose control in individuals with diabetes mellitus, is also related with the incidence of cardiometabolic risk in populations free of disease. The aim of this study was to describe the distribution of HbA_1c levels according to early-life and contemporary factors in adolescents and adults without diabetes mellitus.

Methods

HbA_1c was measured in adults aged 30 years and adolescents aged 18 years who are participants in the 1982 and 1993 Pelotas Birth Cohorts, respectively. Bivariate and multivariate analyses were performed to describe the HbA_1c mean values according to early-life and contemporary characteristics collected prospectively since birth.

Results

The distribution of the HbA_1c was approximately normal in both cohorts, with a mean (SD) 5.10% (0.43) in the 1982 cohort, and 4.89% (0.50) in the 1993 cohort. HbA_1c mean levels were significantly higher in individuals self-reported as black/brown skin color compared to those self-reported as white in both cohorts. Parental history of diabetes was associated with higher HbA_1c mean in adults, while stunting at one year old presented an inverse relation with the outcome in adolescents. No other early and contemporary factors were associated with HbA_1c levels in adults or adolescents.

Conclusions

We found a consistent relationship between HbA_1c and skin color in both cohorts. Further research is needed to understand the role of genomic ancestry on levels of HbA_1c concentrations which may inform policies and preventive actions for diabetes mellitus and cardiometabolic risk.

Relationship between HbA1c and cancer in people with or without diabetes: a systematic review

AIM

To identify the relationship between HbA1c and cancers in people with or without diabetes.

BACKGROUND

Cancer is a major public health problem, accounting for 8.2 million deaths worldwide in 2012. HbA1c level has been associated with the risk of developing certain cancers, although the existing evidence is conflicting.

METHODS

EMBASE, MEDLINE, CINAHL and the Cochrane Library were searched. Eligible articles included randomized controlled trials, cohort studies, case-control studies, systematic reviews and meta-analyses. Participants of either sex, with or without Type 1 or 2 diabetes, were included. The studies were assessed using the Scottish Intercollegiate Guidelines Network (SIGN) criteria by two independent assessors. No meta-analysis was performed because of the heterogeneity of results.

RESULTS

A total of 19 studies from 1006 met the inclusion criteria, of which 14 were cohort studies and five were nested case-control studies. Eight studies investigated outcomes for all cancer sites. Four of these studies reported that higher HbA1c levels were associated with higher incidence and/or mortality risk for all cancers. One study observed a U-shaped relationship between HbA1c and cancer incidence and mortality. Increasing HbA1c levels were associated with increasing risk of developing colorectal, pancreatic, respiratory and female genital tract cancers. No increased risk was observed for breast cancer, gastrointestinal or urological malignancies.

CONCLUSION

HbA1c appears to be associated with cancer incidence and/or cancer mortality, but further studies are needed to fully understand the complex relationship between HbA1c and cancer.

HbA1c and Risks of All-Cause and Cause-Specific Death in Subjects without Known Diabetes: A Dose-Response Meta-Analysis of Prospective Cohort Studies

Whether HbA_1c levels are associated with mortality in subjects without known diabetes remains controversial. Moreover, the shape of the dose–response relationship on this topic is unclear. Therefore, a dose–response meta-analysis was conducted. PubMed and EMBASE were searched. Summary hazard ratios (HRs) were calculated using a random-effects model. Twelve studies were included. The summary HR per 1% increase in HbA_1c level was 1.03 [95% confidence interval (CI) = 1.01–1.04] for all-cause mortality, 1.05 [95% CI = 1.02–1.07) for cardiovascular disease (CVD) mortality, and 1.02 (95% CI = 0.99–1.07) for cancer mortality. After excluding subjects with undiagnosed diabetes, the aforementioned associations remained significant for CVD mortality only. After further excluding subjects with prediabetes, all aforementioned associations presented non-significance. Evidence of a non-linear association between HbA_1c and mortality from all causes, CVD and cancer was found (all P_{non-linearity} < 0.05). The dose–response curves were relatively flat for HbA_1c less than around 5.7%, and rose steeply thereafter. In conclusion, higher HbA_1c level is associated with increased mortality from all causes and CVD among subjects without known diabetes. However, this association is driven by those with undiagnosed diabetes or prediabetes. The results regarding cancer mortality should be treated with caution due to limited studies.

HbA1c levels in non-diabetic older adults - No J-shaped associations with primary cardiovascular events, cardiovascular and all-cause mortality after adjustment for confounders in a meta-analysis of individual participant data from six cohort studies

BACKGROUND

To determine the shape of the associations of HbA1c with mortality and cardiovascular outcomes in non-diabetic individuals and explore potential explanations.

METHODS

The associations of HbA1c with all-cause mortality, cardiovascular mortality and primary cardiovascular events (myocardial infarction or stroke) were assessed in non-diabetic subjects ≥50 years from six population-based cohort studies from Europe and the USA and meta-analyzed. Very low, low, intermediate and increased HbA1c were defined as <5.0, 5.0 to <5.5, 5.5 to <6.0 and 6.0 to <6.5% (equals <31, 31 to <37, 37 to <42 and 42 to <48 mmol/mol), respectively, and low HbA1c was used as reference in Cox proportional hazards models.

RESULTS

Overall, 6,769 of 28,681 study participants died during a mean follow-up of 10.7 years, of whom 2,648 died of cardiovascular disease. Furthermore, 2,493 experienced a primary cardiovascular event. A linear association with primary cardiovascular events was observed. Adjustment for cardiovascular risk factors explained about 50% of the excess risk and attenuated hazard ratios (95 confidence interval) for increased HbA1c to 1.14 (1.03-1.27), 1.17 (1.00-1.37) and 1.19 (1.04-1.37) for all-cause mortality, cardiovascular mortality and cardiovascular events, respectively. The six cohorts yielded inconsistent results for the association of very low HbA1c levels with the mortality outcomes and the pooled effect estimates were not statistically significant. In one cohort with a pronounced J-shaped association of HbA1c levels with all-cause and cardiovascular mortality (NHANES), the following confounders of the association of very low HbA1c levels with mortality outcomes were identified: race/ethnicity; alcohol consumption; BMI; as well as biomarkers of iron deficiency anemia and liver function. Associations for very low HbA1c levels lost statistical significance in this cohort after adjusting for these confounders.

CONCLUSIONS

A linear association of HbA1c levels with primary cardiovascular events was observed. For cardiovascular and all-cause mortality, the observed small effect sizes at both the lower and upper end of HbA1c distribution do not support the notion of a J-shaped association of HbA1c levels because a certain degree of residual confounding needs to be considered in the interpretation of the results.

Lower 1,5-anhydroglucitol is associated with adverse clinical events after percutaneous coronary intervention

Diabetes mellitus and impaired glucose tolerance are well-known risk factors for coronary artery disease (CAD) and adverse clinical events after percutaneous coronary intervention (PCI). Postprandial hyperglycemia is an important risk factor for CAD and serum 1,5-anhydroglucitol (1,5-AG) reflects postprandial hyperglycemia more robustly than hemoglobin (Hb)A1c. We aimed to clarify the relationship between serum 1,5-AG level and adverse clinical events after PCI. We enrolled 141 patients after PCI with follow-up coronary angiography. We evaluated associations between glycemic biomarkers including HbA1c and 1,5-AG and cardiovascular events during follow-up. Median serum 1,5-AG level was significantly lower in patients with any coronary revascularization and target lesion revascularization (TLR) [13.4 µg/ml (first quartile, third quartile 9.80, 18.3) vs. 18.7 (12.8, 24.2), p = 0.005; 13.4 µg/ml (10.2, 16.4) vs. 18.7 (12.9, 24.2), p = 0.001, respectively]. Multivariate logistic analysis showed lower 1,5-AG was independently associated with any coronary revascularization and TLR (odds ratio 0.93, 95 % confidence interval 0.86-0.99, p = 0.04; 0.90, 0.81-0.99, p = 0.044, respectively), whereas higher HbA1c was not. Postprandial hyperglycemia and lower 1,5-AG are important risk factors for adverse clinical events after PCI.

Impact of kidney function and urinary protein excretion on intima-media thickness in Japanese patients with type 2 diabetes

BACKGROUND

Carotid echo indexes [intima-media thickness (IMT)] are commonly used surrogate markers for cardiovascular disease; however, the impacts of chronic kidney disease (CKD) on changes in IMT are unclear. We examined associations between CKD and IMT in participants with and without type 2 diabetes through longitudinal analysis.

METHODS

In total, 424 subjects were enrolled in this study. IMT was measured as per carotid echo indexes. Relationships between IMT and risk factors were analyzed using multiple linear regression analysis, in which we defined IMT as the dependent variable and atherosclerosis-related factors (age, sex, systolic pressure, total cholesterol, body mass index, estimated glomerular filtration rate (eGFR), uric acid, smoking index, number of antihypertensive drugs, statin use, urinary protein levels, past cardiovascular event, glycated hemoglobin, and diabetes duration) as independent variables.

RESULTS

The study population was composed of 70.3 % male subjects. Participants with diabetes accounted for 64.4 % of the total population. The mean follow-up duration was 2.2 ± 1.5 years. Alterations in IMT tended to be associated with systolic blood pressure (+10 mmHg) (β = -0.0084, p = 0.09) and eGFR (+10 mL/min/1.73 m(2)) (β = -0.0049, p = 0.06) in all participants. In participants without diabetes, alterations in IMT were associated with eGFR (+10 mL/min/1.73 m(2)) (β = -0.0104, p = 0.03) and tended to be associated with systolic blood pressure (+10 mmHg) (β = 0.0094, p = 0.06). No significant relationships were found in participants with diabetes.

CONCLUSION

Low eGFR was associated with progression of carotid thickness independent of common cardiovascular risk factors in non-diabetic participants.

Glycated hemoglobin and all-cause and cause-specific mortality in Singaporean Chinese without diagnosed diabetes: the Singapore Chinese Health Study

OBJECTIVE

Glycated hemoglobin (HbA₁c) is a robust biomarker of the preceding 2 to 3 months average blood glucose level. The aim of this study was to examine the association between HbA₁c and mortality in a cohort of Southeast Asians.

RESEARCH DESIGN AND METHODS

Analysis of 7,388 men and women, mean age 62 years, from the Singapore Chinese Health Study who provided a blood sample at the follow-up I visit (1999-2004) and reported no history of diabetes, previous adverse cardiovascular events, or cancer. A total of 888 deaths were identified through 31 December 2011 via registry linkage. Participants represented a random study sample of potential control subjects for a nested case-control genome-wide association study of type 2 diabetes in the population. Hazard ratios (HRs) for all-cause and cause-specific mortality by six categories of HbA1c were estimated with Cox regression models.

RESULTS

Relative to participants with an HbA₁c of 5.4-5.6% (36-38 mmol/mol), participants with HbA₁c ≥6.5% (≥48 mmol/mol) had an increased risk of all-cause, cardiovascular, and cancer mortality during an average of 10.1 years of follow-up; HRs (95% CIs) were 1.96 (1.56-2.46), 2.63 (1.77-3.90), and 1.51 (1.04-2.18), respectively. No level of HbA1c was associated with increased risk of respiratory mortality. Levels <6.5% HbA₁c were not associated with mortality during follow-up. The results did not materially change after excluding observation of first 3 years post-blood draw.

CONCLUSIONS

HbA₁c levels consistent with undiagnosed type 2 diabetes (≥6.5%) are associated with an increased risk of all-cause and cause-specific mortality in Chinese men and women.

Haemoglobin A1c even within non-diabetic level is a predictor of cardiovascular disease in a general Japanese population: the Hisayama Study

Background

There is little information about predictive ability of haemoglobin A1c (HbA1c) for cardiovascular disease (CVD) in Asians. To investigate the discriminatory ability of HbA1c to identify subjects who are at greater risk of developing CVD in a prospective study of a defined community-dwelling Japanese population.

Methods

A total of 2,851 subjects aged 40–79 years were stratified into five groups (HbA1c levels with ≤ 5.0, 5.1–5.4, 5.5–6.4, and ≥ 6.5% and a group with antidiabetic medication) and followed up prospectively for 7 years (2002–2009).

Results

During the follow-up, 119 subjects developed CVD. The multivariable-adjusted risk of CVD was significantly increased in subjects with HbA1c levels of 5.5–6.4 and ≥ 6.5% and diabetic medication compared to HbA1c level with ≤ 5.0% (hazard ratio, 2.26 [95% confidence interval, 1.29–3.95] for the 5.5–6.4%; 4.43 [2.09–9.37] for the ≥ 6.5%; and 5.15 [2.65–10.0] for the antidiabetic medication group). With regard to CVD subtype, the positive associations between HbA1c levels and the risk of coronary heart disease (CHD) and ischaemic stroke were also significant, but no such associations were seen for haemorrhagic stroke. The C statistic for developing CVD was significantly increased by adding HbA1c values to the model including other risk factors (0.789 vs. 0762, p = 0.006), and the net reclassification improvement was 0.105 (p = 0.004).

Conclusions

Our findings suggest that elevated HbA1c levels are an independent risk factor for CVD, especially CHD and ischaemic stroke, and that the addition of HbA1c to the model with traditional risk factors significantly improves the predictive ability of CVD.

Elevated hemoglobin A1c levels are associated with worse survival in advanced pancreatic cancer patients with diabetes

Background/Aims

Pre-existing diabetes mellitus (DM) has been identified as an adverse prognostic variable associated with increased mortality in various cancers. Although DM and hyperglycemia are considered risk factors for pancreatic cancer (PC), antidiabetic treatments for patients with advanced PC have been overlooked. This study aimed to evaluate the impact of hemoglobin A1c (HbA1c) levels on PC survival.

Methods

We retrospectively reviewed the medical records of first-diagnosed patients with advanced PC who were admitted to Konkuk University Medical Center from 2005 to 2011.

Results

A total of 127 patients were enrolled, and there were 111 deaths (87.4%) within the 7-year observational period. The most common etiology was disease progression (n=108). DM before PC diagnosis was observed in 65 patients (51.1%), including 28 patients with new-onset DM. The overall median survival times in patients with and without DM were 198 and 263 days, respectively (p=0.091). Survival time according to HbA1c was significantly different between the <7.0% and ≥7.0% groups (362 and 144 days, respectively; p=0.038). In the HbA1c ≥7.0% group, the median overall survival time was 273 days for the metformin group and 145 days for the nonmetformin oral agent group; however, there was no significant difference between the two groups (p=0.058).

Conclusions

A high HbA1c level may be associated with worse survival in patients with advanced PC with DM. Antidiabetic treatment, metformin in particular, was associated with an improved outcome.

HbA1c and the risks for all-cause and cardiovascular mortality in the general Japanese population: NIPPON DATA90

OBJECTIVE

Associations between HbA1c and cardiovascular diseases (CVD) have been reported mainly in Western countries. It is not clear whether HbA1c measurements are useful for assessing CVD mortality risk in East Asian populations.

RESEARCH DESIGN AND METHODS

The risk for cardiovascular death was evaluated in a large cohort of participants selected randomly from the overall Japanese population. A total of 7,120 participants (2,962 men and 4,158 women; mean age 52.3 years) free of previous CVD were followed for 15 years. Adjusted hazard ratios (HRs) and 95% CIs among categories of HbA1c (<5.0%, 5.0-5.4%, 5.5-5.9%, 6.0-6.4%, and ≥6.5%) for participants without treatment for diabetes and HRs for participants with diabetes were calculated using a Cox proportional hazards model.

RESULTS

During the study, there were 1,104 deaths, including 304 from CVD, 61 from coronary heart disease, and 127 from stroke (78 from cerebral infarction, 25 from cerebral hemorrhage, and 24 from unclassified stroke). Relations to HbA1c with all-cause mortality and CVD death were graded and continuous, and multivariate-adjusted HRs for CVD death in participants with HbA1c 6.0-6.4% and ≥6.5% were 2.18 (95% CI 1.22-3.87) and 2.75 (1.43-5.28), respectively, compared with participants with HbA1c <5.0%. Similar associations were observed between HbA1c and death from coronary heart disease and death from cerebral infarction.

CONCLUSIONS

High HbA1c levels were associated with increased risk for all-cause mortality and death from CVD, coronary heart disease, and cerebral infarction in general East Asian populations, as in Western populations.

Relationship between fasting and 2-hour postprandial plasma glucose levels and vascular complications in patients with type 2 diabetes mellitus

OBJECTIVE

To investigate the relationship between fasting and 2-h postprandial plasma glucose concentrations and vascular complications in type 2 diabetes.

METHODS

Consecutive patients with type 2 diabetes admitted for blood glucose control were grouped according to their fasting and 2-h postprandial plasma glucose levels. Frequency and severity of diabetic retinopathy and nephropathy, number of carotid artery plaques, coefficient of variation of R-R intervals (CVRR), brachial-ankle pulse wave velocity (baPWV), intima-media thickness, brain natriuretic peptide level, ankle-brachial index, and high-sensitivity C-reactive protein levels were compared.

RESULTS

In the 206 patients studied, mean±SD age, glycosylated haemoglobin and duration of diabetes were 63.4±13.7 years, 9.8±1.8% and 13.4±8.9 years, respectively. Patients with high fasting plasma glucose levels had a higher frequency of proliferative retinopathy than those with low fasting levels. Patients with medium or high 2-h postprandial plasma glucose levels had higher baPWV and lower CVRR, respectively, than those with low 2-h levels. There was an inverse correlation between baPWV and CVRR.

CONCLUSION

Elevated fasting and postprandial plasma glucose levels are risk factors for vascular complications in type 2 diabetes mellitus.

Association of adiponectin with dietary factors and cardiovascular risk factors in type 2 diabetes mellitus patients

BACKGROUND AND AIM

Adiponectin, is an adipose tissue-specific adipokine, that circulates in human plasma at high levels, although lower levels are noted with insulin resistance and atherosclerosis. We investigated the relationship of adiponectin concentrations with dietary factors and some of the cardiovascular risk factors in patients with T2DM.

METHODS AND RESULTS

Totally 107 patients with T2DM were recruited from the out patients clinic of Shariati Hospital, Tehran, Iran. Patients were evaluated for laboratory and anthropometric measurements including serum adiponectin, fasting insulin, FPG, OGTT, HbA1c, HOMA-IR, hsCRP, weight, height, BMI and WHR. Nutrients intakes were obtained via 24-h recall from each patient in three successive days. Nutrients and data analysis were done using FPII and SPSS version 13 softwares. The mean of log10-transformed serum adiponectin concentration was 0.79±0.27μg/ml. The univariate linear regression analysis could not show any significant relation between the log of serum adiponectin and dietary factors. In multivariate linear regression after multiple adjustment, the log of serum adiponectin was independently associated with WHR (P=0.02, t=-2.33), HDL-C (P=0.050, t=2.03) and markedly but not significantly with age of patients (P=0.058, t=1.92).

CONCLUSIONS

Our findings showed that WHR, one of the important cardiovascular risk factors, can modulate independently adiponectin levels of T2DM patients in inverse manner. Also, the age of patients and HDL-C levels have marked positive effect on circulating levels of this adipocytokine. Thus, adiponectin might be a useful biomarker to prevent developing CVD in type 2 diabetes.

All-cause mortality and pharmacological treatment intensity following a high risk screening program for diabetes. A 6.6 year follow-up of the ADDITION study, Denmark

AIM

To study all-cause mortality and pharmacological treatment intensity in relation to baseline glucose metabolism and HbA1c following high risk screening for diabetes in primary care.

METHODS

Persons aged 40-69 years (N=163,185) received mailed diabetes risk questionnaires. 20,916 persons without diabetes but with high risk of diabetes were stratified by glucose metabolism (normal glucose tolerance (NGT), dysglycemia (IFG or IGT) or diabetes) and by HbA1c at screening (<6%, 6.0-6.4% or ≥ 6.5%). Median follow-up was 6.6 years. Excess mortality was calculated by hazard ratio.

RESULTS

HR for all-cause mortality increased with increasing levels of HbA1c at screening in people with NGT and dysglycemia. In people with screen detected diabetes the opposite relation was found. In people with diabetes redeemed prescription rates for lipid-, blood pressure- and glucose-lowering drugs increased significantly following screening and prescription rates increased with increasing levels of HbA1c at screening. The same trend in redeemed prescriptions was seen for people with dysglycemia and NGT, but the absolute rates were significantly lower than those among people with screen detected diabetes.

CONCLUSIONS

This study confirms HbA1c as an independent predictor of all-cause mortality in non-diabetic individuals. A likely explanation for the inverse relation found between all-cause mortality and HbA1c at screening among those with screen detected diabetes would be that intensive treatment near-normalizes mortality. The small group of people with NGT and HbA1c ≥ 6.5%, who had the highest all-cause mortality, may benefit from being labelled and treated as having diabetes although this group may have special characteristics not accounted for in this study.

Association between HbA1c and cardiovascular disease mortality in older Hong Kong Chinese with diabetes

OBJECTIVE

To examine the association between baseline HbA(1c) level and mortality attributable to all-cause, cardiovascular disease, coronary heart disease and stroke.

METHODS

A total of 2137 Chinese aged 65 years or above attending the Elderly Health Service, Department of Health, Hong Kong, with diagnosed diabetes had HbA(1c) measured during 1998 to 2000 and were followed up to 2009. Information on socio-economic position, lifestyle factors and disease history was collected. Hazard ratios and 95% confidence intervals with adjustment for potential confounders were calculated using Cox's proportional hazards models.

RESULTS

After an average of 7.9 years of follow-up, 540 participants had died. After adjusting for potential confounders, higher HbA(1c) (≥ 69 mmol/mol, 8.5%) increased the risk of cardiovascular disease (hazard ratio 2.11;95% CI 1.37-3.25) and stroke mortality (hazard ratio 2.43; 95% CI 1.06-5.55) compared with HbA(1c) of 58-68 mmol/mol (7.5-8.4%), and increased the risk of all-cause (hazard ratio 1.41; 95% CI 1.06-1.86) and coronary heart disease mortality (hazard ratio 2.44; 95% CI 1.11-5.37) compared with HbA(1c) of 48 mmol/mol (6.5%) or less. Analysis of HbA(1c) as a continuous variable showed that every XX mmol/mol (1%) increase in HbA(1c) decreased stroke mortality risk by 51% in those with HbA(1c) level less than 48 mmol/mol (6.5%) and increased stroke mortality risk by 30% in those with an HbA(1c) level of 48 mmol/mol (6.5%) or higher, suggesting a U-shaped association between HbA(1c) and stroke mortality.

CONCLUSION

High HbA(1c) predicted excess risk of all-cause, cardiovascular disease, coronary heart disease and stroke mortality. The question of whether low HbA(1c) increases mortality in older patients with diabetes needs further investigation.

Glycated hemoglobin and cancer incidence and mortality in the Atherosclerosis in Communities (ARIC) Study, 1990-2006

Diabetes is a risk factor for many cancers; chronic hyperglycemia is hypothesized to be, in part, explanatory. We evaluated the association between glycated hemoglobin, a time-integrated glycemia measure, and cancer incidence and mortality in nondiabetic and diabetic men and women. We conducted a prospective study of 12,792 cancer-free participants attending the second visit (1990-1992) of the Atherosclerosis Risk in Communities (ARIC) Study. We measured glycated hemoglobin in whole-blood samples using HPLC. Incident cancers were ascertained from registries and hospital records through 2006. We estimated multivariable-adjusted hazard ratios (HR) of cancer incidence and mortality for nondiabetic participants with values ≥ 5.7% (elevated), nondiabetic participants with <5.0% (low) and diabetic participants all compared with nondiabetic participants with 5.0-5.6% (normal). We ascertained 2,349 incident cancer cases and 887 cancer deaths. Compared with nondiabetic women with normal glycated hemoglobin, nondiabetic women with elevated values had an increased risk of cancer incidence (HR:1.24; 95% CI:1.07,1.44) and mortality (HR:1.58; 95% CI:1.23,2.05) as did diabetic women (incidence, HR:1.30; 95% CI:1.06,1.60, mortality, HR:1.96; 95% CI:1.40,2.76). Nondiabetic women with low values also had increased risk. Diabetic women with good glycemic control (<7.0%) had a lower cancer risk than those with higher values. Glycated hemoglobin in nondiabetic and diabetic men, and diabetes were not statistically significantly associated with total cancer risk. Our findings support the hypothesis that chronic hyperglycemia, even in the nondiabetic range, increases cancer risk in women. Maintaining normal glycated hemoglobin overall, and good glycemic control among diabetic adults, may reduce the burden of cancer, especially in women.

Time and Costs of Insulin Treatment in the Care of Newly Registered Type 2 Diabetes Patients in Diabetes Clinics Across Japan (JDDM 22)

AIMS

To study the time and costs of insulin treatment of newly registered outpatients with Type 2 diabetes mellitus (T2DM).

METHODS

In total, 355 patients with T2DM were registered on their first visit to one of 11 diabetes clinics across Japan. Of these, 313 were not being treated with insulin (the non-insulin group), whereas 42 were (the insulin group). In the insulin group, 26 were already on insulin at the first visit, whereas 16 were started on insulin after their first visit. The time and costs involved in the care were recorded over the following 5 months.

RESULTS

In the first 3 months, considerable time was expended in both groups, with the time spent by physicians a little (but significantly) longer for the insulin group. The total time expended by all care providers was approximately 1.3-fold greater for the insulin compared with the non-insulin group. The total cost and total cost/min for the insulin group was almost twice that for the non-insulin group. Over the 5-month period, mean HbA1c in the non-insulin group improved from 8.0% to 6.5%, with 72% achieving a glycemic target of HbA1c ≤ 6.5%. In contrast, in the insulin group, mean HbA1c improved from 9.4% to 7.6%, with only 39% achieving the target. There were no reports of major hypoglycemic events in either group and body mass index remained stable.

CONCLUSIONS

The insulin therapy for T2DM can be achieved safely and effectively at outpatient clinics, even though it requires considerably more time and resources than non-insulin therapy.

HbA1c as predictor of all-cause mortality in individuals at high risk of diabetes with normal glucose tolerance, identified by screening: a follow-up study of the Anglo-Danish-Dutch Study of Intensive Treatment in People with Screen-Detected Diabetes in Primary Care (ADDITION), Denmark

AIMS/HYPOTHESIS

Stepwise screening for type 2 diabetes will not only identify people with the disease or some other form of dysglycaemia (impaired fasting glucose or impaired glucose tolerance), but also many individuals who are phenotypically at high risk of developing diabetes, but currently have normal glucose tolerance (NGT). We therefore sought to assess whether HbA(1c) adds prognostic information in relation to all-cause mortality in people who have NGT and a high risk of type 2 diabetes mellitus.

METHODS

In a Danish population-based stepwise screening programme for type 2 diabetes mellitus in general practice, we identified 15,634 persons at high risk of type 2 diabetes, who had NGT and a recorded HbA(1c) measurement. As comparison groups, we included 1,401 people identified as having type 2 diabetes mellitus and 8,149 individuals characterised as being at low risk of diabetes. All individuals were followed from time of screening (April 2001 to December 2006) until death or 31 October 2009. Excess mortality was estimated using Cox proportional hazard models with all-cause mortality as the outcome measure.

RESULTS

Compared with individuals with NGT and HbA(1c) below 6.0%, adjusted hazard ratios were: 1.21 (95% CI 0.95-1.56) for individuals with NGT and HbA(1c) between 6.0% and 6.5%; 2.48 (95% CI 1.23-4.99) for individuals with NGT and HbA(1c) 6.5% or above (in this group there were eight deaths among 68 individuals); 1.73 (95% CI 1.40-2.13) for individuals with type 2 diabetes mellitus.

CONCLUSIONS/INTERPRETATION

HbA(1c) level in people with NGT and at high risk of diabetes was clearly associated with increased all-cause mortality.

New diagnosis criteria for diabetes with hemoglobin A1c and risks of macro-vascular complications in an urban Japanese cohort: the Suita study

The association of the new diagnosis criteria for diabetes adopting hemoglobin A1c, recently proposed by the international expert committee, with macro-vascular complications was tested in a 12-year population-based cohort. The present analysis suggested that this new criteria were applicable to macro-vascular complications in the Japanese.

Performance of an A1C and fasting capillary blood glucose test for screening newly diagnosed diabetes and pre-diabetes defined by an oral glucose tolerance test in Qingdao, China

OBJECTIVE The study's goal was to evaluate the performance of A1C and fasting capillary blood glucose (FCG) tests as mass screening tools for diabetes and pre-diabetes, as determined by the standard oral glucose tolerance test (OGTT). RESEARCH DESIGN AND METHODS Data from 2,332 individuals aged 35-74 years who participated in a population-based cross-sectional diabetes survey in Qingdao, China, were analyzed. A 2-h 75-g OGTT was used to diagnose diabetes. The performance of A1C and FCG was evaluated against the results of the OGTTs by using receiver operating characteristic curve (ROC) analysis. RESULTS The prevalence of newly diagnosed diabetes and pre-diabetes (impaired fasting glucose and/or impaired glucose tolerance) was 11.9 and 29.5%, respectively. For subjects with newly diagnosed diabetes, the area under the ROC curve was 0.67 for A1C and 0.77 for FCG (P < 0.01) in men and 0.67 and 0.75 (P < 0.01) in women, whereas for pre-diabetes, these values were 0.47 and 0.64 (P < 0.001) in men and 0.51 and 0.65 (P < 0.001) in women. At the optimal A1C cutoff point of > or =5.6% for newly diagnosed diabetes, sensitivities (specificities) were 64.4% (61.6%) for men and 62.3% (63.3%) for women. CONCLUSIONS As a screening tool for newly diagnosed diabetes and pre-diabetes, the FCG measurement performed better than A1C in this general Chinese population.

GHb level and subsequent mortality among adults in the U.S

OBJECTIVE To examine the association of hyperglycemia, as measured by GHb, with subsequent mortality in a nationally representative sample of adults. RESEARCH DESIGN AND METHODS We included adults aged > or =20 years who participated in Third National Health and Nutrition Examination Survey (1988-1994) and had complete information, including baseline diabetes status by self-report and measured GHb (n = 19,025) and follow-up through the end of 2000 for mortality. RESULTS In the overall population, higher levels of GHb were associated with increased risk of mortality from all causes, heart disease, and cancer. After adjustment for potential risk factors, the relative hazard (RH) for adults with GHb > or =8% compared with adults with GHb <6% was 2.59 (95% CI 1.88-3.56) for all-cause mortality, 3.38 (1.98-5.77) for heart disease mortality, and 2.64 (1.17-5.97) for cancer mortality. Among adults with diagnosed diabetes, having GHb > or =8% compared with GHb <6% was associated with higher all-cause mortality (RH 1.68, 95% CI 1.03-2.74) and heart disease mortality (2.48, 1.09-5.64), but there was no increased risk of cancer mortality by GHb category. Among adults without diagnosed diabetes, there was no significant association of all-cause, heart disease, or cancer mortality and GHb category. CONCLUSIONS These results highlight the importance of GHb levels in mortality risk among a nationally representative sample of adults with and without diagnosed diabetes and indicate that higher levels are associated with increased mortality in adults with diabetes.

Hyperglycemia increases risk of gastric cancer posed by Helicobacter pylori infection: a population-based cohort study

BACKGROUND & AIMS

Although diabetes mellitus and hyperglycemia are considered to be possible risk factors for various types of malignancy, the epidemiologic evidence concerning gastric cancer is scarce. The aim of this study was to evaluate the impact of hemoglobin A1c (HbA1c) levels on gastric cancer occurrence and their interaction with Helicobacter pylori infection.

METHODS

A total of 2603 Japanese subjects aged>or=40 years were stratified into 4 groups according to baseline HbA1c levels (<or=4.9%, 5.0%-5.9%, 6.0%-6.9%, and >or=7.0%) and followed up prospectively for 14 years.

RESULTS

During the follow-up, 97 subjects developed gastric cancer. The age- and sex-adjusted incidence of gastric cancer significantly increased in the 6.0%-6.9% (5.1 per 1000 person-years; P<.05) and >or=7.0% groups (5.5 per 1000 person-years; P<.05) compared with the 5.0%-5.9% group (2.5 per 1000 person-years), whereas it was slightly but not significantly high in the <or=4.9% group (3.6 per 1000 person-years). This association remained substantially unchanged even after adjusting for the confounding factors including Helicobacter pylori seropositivity, (multivariate-adjusted hazard ratio [HR], 2.13; 95% confidence interval [CI]: 1.30-3.47 for the 6.0%-6.9% group and HR, 2.69; 95% CI: 1.24-5.85 for the >or=7.0% group). Among subjects who had both high HbA1c levels (>or=6.0%) and Helicobacter pylori infection, the risk of gastric cancer was dramatically elevated (interaction term, P=.004).

CONCLUSIONS

Our findings suggest that casual hyperglycemia is a risk factor for gastric cancer and is a possible cofactor increasing the risk posed by Helicobacter pylori infection.

Continuous relationships between non-diabetic hyperglycaemia and both cardiovascular disease and all-cause mortality: the Australian Diabetes, Obesity, and Lifestyle (AusDiab) study

AIMS/HYPOTHESIS

Hyperglycaemia is a risk factor for cardiovascular disease (CVD) and all-cause mortality in individuals without diabetes. We investigated: (1) whether the risk of all-cause and CVD mortality extended continuously throughout the range of fasting plasma glucose (FPG), 2 h plasma glucose (2hPG) and HbA(1c) values; and (2) the ability of these measures to improve risk prediction for mortality.

METHODS

Data on 10,026 people aged >or=25 years without diagnosed diabetes were obtained from the population-based Australian Diabetes, Obesity and Lifestyle study. Between 1999 and 2000, FPG, 2hPG and HbA(1c) were assessed and all-cause (332 deaths) and CVD (88 deaths) mortality were obtained after 7 years.

RESULTS

Both 2hPG and HbA(1c) exhibited linear relationships with all-cause and CVD mortality, whereas FPG showed J-shaped relationships. The adjusted HR (95% CI) for all-cause mortality per SD increase was 1.2 (1.1-1.3) for 2hPG and 1.1 (1.0-1.2) for HbA(1c). The HR for FPG <5.1 mmol/l (per SD decrease) was 2.0 (1.3-3.0); for FPG >or=5.1 mmol/l (per SD increase) the HR was 1.1 (1.0-1.2). Corresponding HRs for CVD mortality were 1.2 (1.0-1.4), 1.2 (1.0-1.3), 4.0 (2.1-7.6) and 1.3 (1.1-1.4). The discriminative ability of each measure was similar; no measure substantially improved individual risk identification over traditional risk factors.

CONCLUSIONS/INTERPRETATION

In individuals without diagnosed diabetes, 2hPG and FPG, but not HbA(1c) were significant predictors of all-cause mortality, whereas all measures were significant predictors of CVD mortality. However, these glucose measures did not substantially improve individual risk identification.

Impaired microvascular perfusion: a consequence of vascular dysfunction and a potential cause of insulin resistance in muscle

Insulin has an exercise-like action to increase microvascular perfusion of skeletal muscle and thereby enhance delivery of hormone and nutrient to the myocytes. With insulin resistance, insulin's action to increase microvascular perfusion is markedly impaired. This review examines the present status of these observations and techniques available to measure such changes as well as the possible underpinning mechanisms. Low physiological doses of insulin and light exercise have been shown to increase microvascular perfusion without increasing bulk blood flow. In these circumstances, blood flow is proposed to be redirected from the nonnutritive route to the nutritive route with flow becoming dominant in the nonnutritive route when insulin resistance has developed. Increased vasomotion controlled by vascular smooth muscle may be part of the explanation by which insulin mediates an increase in microvascular perfusion, as seen from the effects of insulin on both muscle and skin microvascular blood flow. In addition, vascular dysfunction appears to be an early development in the onset of insulin resistance, with the consequence that impaired glucose delivery, more so than insulin delivery, accounts for the diminished glucose uptake by insulin-resistant muscle. Regular exercise may prevent and ameliorate insulin resistance by increasing "vascular fitness" and thereby recovering insulin-mediated capillary recruitment.

A New Zealand linkage study examining the associations between A1C concentration and mortality

OBJECTIVE

To examine associations between A1C concentration and mortality in a New Zealand population.

RESEARCH DESIGN AND METHODS

During a Hepatitis Foundation screening campaign for hepatitis B (1999-2001), participants were offered A1C testing. The participants were anonymously linked to the national mortality collection to 31 December 2004. Hazard ratios (HRs) and 95% CIs adjusted for age, ethnicity, smoking, and sex were estimated using Cox regression.

RESULTS

There were 47,904 participants (71% Mâori, 12% Pacific, 5% Asian, and 12% other). A1C measurements were categorized as <4.0% (n = 142), 4.0 to <5.0% (reference category; n = 12,867), 5.0 to <6.0% (n = 30,222), 6.0 to <7.0% (n = 2,669), and >or=7.0% (n = 1,596); there were also 408 participants with a previous diabetes diagnosis. During the follow-up period, 815 individuals died. In those without a prior diabetes diagnosis, there were steadily increasing HRs from the A1C reference category to the highest category (>or=7.0%; HR 2.36 [95% CI 1.72-3.25]). As well as all-cause mortality, A1C was associated with mortality from diseases of the circulatory system; endocrine, nutritional, metabolic, and immunity disorders; and other and unknown causes. Mortality was also elevated in those with a prior diabetes diagnosis (5.19 [3.67-7.35]), but this was only partially explained by their elevated A1C levels.

CONCLUSIONS

This is the largest study to date of A1C levels and subsequent mortality risk. It confirms previous findings that A1C levels are strongly associated with subsequent mortality in both men and women without a prior diabetes diagnosis.

Relation of blood pressure and all-cause mortality in 180,000 Japanese participants: pooled analysis of 13 cohort studies

Hypertension is a leading cause of death because of cardiovascular disease and predominantly affects total mortality. To reduce avoidable deaths from hypertension, we need to collect blood pressure data and assess their impact on total mortality. To examine this issue, a meta-analysis of 13 cohort studies was conducted in Japan. Poisson regression was used for estimating all-cause mortality rates and ratios. In the model, blood pressure data were treated as continuous (10-mm Hg increase) and categorical (every 10 mm Hg) according to recommendations of the Seventh Joint National Committee on Prevention, Detection, Evaluation, and Treatment of Hypertension. Potential confounders included body mass index, smoking, drinking, and cohort. The impact of hypertension was measured by the population-attributable fraction. After excluding participants with cardiovascular disease history, 176 389 participants were examined in the analysis. Adjusted mortality rates became larger as the blood pressure increased, and these were more distinct in younger men and women. Hazard ratios also showed the same trends, and these trends were more apparent in younger men (hazard ratio [unit: 10-mm Hg increase] aged 40 to 49 years: systolic blood pressure 1.37 (range: 1.15 to 1.62); diastolic blood pressure 1.46 [range: 1.05 to 2.03]) than older ones (hazard ratio: aged 80 to 89 years: systolic blood pressure 1.09 [range: 1.05 to 1.13]and diastolic blood pressure 1.12 [range: 1.03 to 1.22]). Population-attributable fraction of hypertension was approximately 20% when the normal category was used as a reference level and was 10% when we included the prehypertension group in the reference level. In conclusion, high blood pressure raised the risk of total mortality, and this trend was higher in the younger Japanese population.

HbA1c measured in stored erythrocytes and mortality rate among middle-aged and older women

AIMS/HYPOTHESIS

Diabetes is known to increase mortality rate, but the degree to which mild hyperglycaemia may be associated with the risk of death is uncertain. We examined the association between HbA1c measured in stored erythrocytes and mortality rate in women with and without diabetes.

METHODS

We conducted a cohort study of 27,210 women>or=45 years old with no history of cardiovascular disease or cancer who participated in the Women's Health Study, a randomised trial of vitamin E and aspirin.

RESULTS

Over a median of 10 years of follow-up, 706 women died. Proportional hazards models adjusted for age, smoking, hypertension, blood lipids, exercise, postmenopausal hormone use, multivitamin use and C-reactive protein were used to estimate the relative risk of mortality. Among women without a diagnosis of diabetes and HbA1c<5.60%, those in the top quintile (HbA1c 5.19-5.59%) had a relative risk of mortality of 1.28 (95% CI 0.98-1.69, p value for linear trend=0.14) compared with those with HbA1c 2.27-4.79%. Women with HbA1c 5.60-5.99% and no diagnosis of diabetes had a 54% increased risk of mortality (95% CI 1-136%) compared with those with HbA1c 2.27-4.79%. HbA1c was significantly associated with mortality across the range 4.50-7.00% (p value for linear trend=0.02); a test of deviation from linearity was not statistically significant (p=0.67). Diabetic women had more than twice the mortality risk of non-diabetic women.

CONCLUSIONS/INTERPRETATION

This study provides further evidence that chronic mild hyperglycaemia, even in the absence of diagnosed diabetes, is associated with increased risk of mortality. ClinicalTrials.gov ID no.: NCT00000479.

Self-reported diabetes mellitus and risk of mortality from all causes, cardiovascular disease, and cancer in Takayama: a population-based prospective cohort study in Japan

BACKGROUND

Diabetes mellitus has been reported to be a major risk factor for cardiovascular disease (CVD), and higher risk of CVD among women than that among men has been observed in many studies. Further, the association of diabetes with increasing risk of cancer has also been reported. Well-designed studies conducted among men and women in the general Japanese population remain scarce.

METHODS

Our cohort consisted of 13355 men and 15724 women residing in Takayama, Japan, in 1992. At the baseline, the subjects reported diabetes in a questionnaire. Any deaths occurring in the cohort until 1999 were noted by using data from the Office of the National Vital Statistics. The risk of mortality was separately assessed for men and women by using a Cox proportional hazard model after adjusting for age; smoking status; body mass index (BMI); physical activity; years of education; history of hypertension; and intake of total energy, vegetables, fat, and alcohol.

RESULTS

Diabetes significantly increased the risk of mortality from all causes [hazard ratio (HR): 1.35, 95% confidence interval (CI): 1.11-1.64] and from coronary heart disease (CHD) (HR: 2.96, 95% CI: 1.59-5.50) among men, and that from all causes (HR: 1.74, 95% CI: 1.34-2.26) and cancer (HR: 1.88, 95% CI: 1.16-3.05) among women. Diabetes was not significantly associated with mortality from CHD among women.

CONCLUSION

The findings suggest that diabetes increases the risk of mortality from CVD among men and that from cancer among women. The absence of increased risk of mortality from CHD among women may suggest a particular pattern in the Japanese population.

Time and cost involved in the care of newly registered patients with diabetes mellitus and other lifestyle diseases at diabetes clinics in Japan (JDDM 4)

AIMS

To study the time and cost involved in the care of newly registered outpatients with Type 2 diabetes mellitus (DM), compared with patients with hypertension and/or hyperlipidaemia (HTL).

METHODS

A total of 313 patients with DM and 58 patients with HTL without diabetes were registered on their first visits to 11 diabetes clinics across Japan. The time and cost involved in their care was recorded over the following 5 months.

RESULTS

In the first 3 months, there was an extensive time commitment to both groups. The time spent by physicians was 1.5 times longer for DM than for HTL. The total care time spent by all the care providers for DM was twice that for HTL. The cost of DM care was twice that for HTL, with the cost of medicines excluded. However, half of the cost for DM was for laboratory tests. When these were excluded, and the remaining cost divided by the time spent, the amount for DM was half of that for HTL. Over the 5 months, mean glycated haemoglobin (HbA(1c)) in DM patients improved from 8.0% to 6.5%, and 72% of DM patients achieved the glycaemic target of HbA(1c) < or = 6.5%.

CONCLUSIONS

DM care in a diabetes clinic requires a great deal more time and resources than HTL to achieve the best outcome. An educational system for self care, presently lacking in the primary care setting in Japan, would improve glycaemic control for DM patients in the community.