Mortality in a cohort of diabetic patients. Causes and relative risks

The importance of the AMPK gamma 1 subunit in metformin suppression of liver glucose production

Metformin has been used to treat patients with type 2 diabetes for over 60 years, however, its mechanism of action is still not completely understood. Our previous reports showed that high-fat-diet (HFD)-fed mice with liver-specific knockout of both AMPK catalytic α1 and α2 subunits exhibited significantly higher fasting blood glucose levels and produced more glucose than floxed AMPK catalytic α1 and α2 mice after long-term metformin treatment, and that metformin promotes the formation of the functional AMPK αβγ heterotrimeric complex. We tested the importance of each regulatory γ subunit isoform to metformin action in this current study. We found that depletion of γ1, but not γ2 or γ3, drastically reduced metformin activation of AMPK. HFD-fed mice with depletion of the γ1 subunit are resistant to metformin suppression of liver glucose production. Furthermore, we determined the role of each regulatory cystathionine-β-synthase (CBS) domain in the γ1 subunit in metformin action and found that deletion of either CBS1 or CBS4 negated metformin's effect on AMPKα phosphorylation at T172 and suppression of glucose production in hepatocytes. Our data indicate that the γ1 subunit is required for metformin's control of glucose metabolism in hepatocytes. Furthermore, in humans and animal models, metformin treatment leads to the loss of body weight, we found that the decrease in body weight gain in mice treated with metformin is not directly attributable to increased energy expenditure.

Effects of body mass index, abdominal obesity, and type 2 diabetes on mortality in community-dwelling elderly in Sao Paulo, Brazil: analysis of prospective data from the SABE study

BACKGROUND

The majority of studies on the effects of adiposity on mortality in the elderly have been conducted in developed countries with mixed results. We investigated the association between adiposity and mortality in a cohort of community-dwelling elderly in Sao Paulo, Brazil.

METHODS

Body mass index (BMI), waist circumference, waist-to-hip ratio, and type 2 diabetes were evaluated in 1,882 participants (mean age 71.0 ± 8.3 years old, 61% female). Mortality was confirmed by national vital statistics records during a maximum of 10 years of follow-up. Proportional hazards models were used to estimate hazard ratios (HRs) for mortality after adjusting for sociodemographics and comorbidities. In a subsample of 897 participants, the effects of changes in measures of adiposity on mortality were investigated during a median follow-up of 4.6 years.

RESULTS

Having type-2 diabetes at baseline was associated with increased mortality (HR = 1.44, 95% CI: 1.17-1.77), with a higher HR among men. When compared with normal weight participants (BMI = 20-<25kg/m(2)), overweight and obesity were not associated with mortality (overweight: HR = 0.84 [0.70, 1.02]; obesity: HR = 0.82 [0.64, 1.06]), whereas participants with low-normal weight (BMI = 18.5<20 kg/m(2)) had increased risk of death (HR = 1.51 [1.08-2.10]). Higher waist circumference and waist-to-hip ratio were not associated with increased mortality. Weight gain was protective against mortality in all BMI categories, except in obese participants, and weight loss increased the risk of death in all BMI categories by 42-63%.

CONCLUSIONS

In community-dwelling elderly in Sao Paulo, overweight and obesity were not associated with a higher risk of death, and weight gain seemed to reduce mortality, except in the obese.

Predictors of diabetic nephropathy

Diabetic nephropathy (DN) is a leading cause of morbidity and mortality in diabetic patients representing a huge health and economic burden. Alarming recent data described diabetes as an unprecedented worldwide epidemic, with a prevalence of ∼6.4% of the world population in 2010, while the prevalence of CKD among diabetics was approximately 40%. With a clinical field hungry for novel markers predicting DN, several clinical and laboratory markers were identified lately with the promise of reliable DN prediction. Among those are age, gender, hypertension, smoking, sex hormones and anemia. In addition, eccentric left ventricular geometric patterns, detected by echocardiography, and renal hypertrophy, revealed by ultrasonography, are promising new markers predicting DN development. Serum and urinary markers are still invaluable elements, including serum uric acid, microalbuminuria, macroalbuminuria, urinary liver-type fatty acid-binding protein (u-LFABP), and urinary nephrin. Moreover, studies have illustrated a tight relationship between obstructive sleep apnea and the development of DN. The purpose of this review is to present the latest advances in identifying promising predictors to DN, which will help guide the future research questions in this field. Aiming at limiting this paramount threat, further efforts are necessary to identify and control independent modifiable risk factors, while developing an integrative algorithm for utilization in DN future screening programs.

Nocturnal blood pressure fall as predictor of diabetic nephropathy in hypertensive patients with type 2 diabetes

BACKGROUND

Hypertensive patients with reduced blood pressure fall (BPF) at night are at higher risk of cardiovascular events (CVE).

METHODS

We evaluated in hypertensive diabetic patients, if a reduced nocturnal BPF can precedes the development of diabetic nephropathy (DN). We followed 70 patients with normal urinary albumin excretion (UAE) for two years. We performed 24-hours ambulatory BP monitoring in baseline and at the end of the study.

RESULTS

Fourteen (20%) patients (GI) developed DN (N = 11) and/or CVE (n = 4). Compared to the remaining 56 patients (GII) in baseline, GI had similar diurnal systolic (SBP) and diastolic BP (DBP), but higher nocturnal SBP (138 +/- 15 vs 129 +/- 16 mmHg; p < 0.05) and DBP (83 +/- 12 vs 75 +/- 11 mmHg; p < 0,05). Basal nocturnal SBP correlated with occurrence of DN and CVE (R = 0.26; P < 0.05) and with UAE at the end of the study (r = 0.3; p < 0.05). Basal BPF (%) correlated with final UAE (r = -0.31; p < 0.05). In patients who developed DN, reductions occurred in nocturnal systolic BPF (12 +/- 5 vs 3 +/- 6%, p < 0,01) and diastolic BPF (15 +/- 8 vs 4 +/- 10%, p < 0,01) while no changes were observed in diurnal SBP (153 +/- 17 vs 156 +/- 16 mmHg, NS) and DBP (91 +/- 9 vs 90 +/- 7 mmHg, NS). Patients with final UAE < 20 microg/min, had no changes in nocturnal and diurnal BP.

CONCLUSIONS

Our results suggests that elevations in nocturnal BP precedes DN and increases the risk to develop CVE in hypertensive patients with T2DM.

Socioeconomic inequalities in diabetes mellitus across Europe at the beginning of the 21st century

AIMS/HYPOTHESIS

The aim of this study was to determine and quantify socioeconomic position (SEP) inequalities in diabetes mellitus in different areas of Europe, at the turn of the century, for men and women.

METHODS

We analysed data from ten representative national health surveys and 13 mortality registers. For national health surveys the dependent variable was the presence of diabetes by self-report and for mortality registers it was death from diabetes. Educational level (SEP), age and sex were independent variables, and age-adjusted prevalence ratios (PRs) and risk ratios (RRs) were calculated.

RESULTS

In the overall study population, low SEP was related to a higher prevalence of diabetes, for example men who attained a level of education equivalent to lower secondary school or less had a PR of 1.6 (95% CI 1.4-1.9) compared with those who attained tertiary level education, whereas the corresponding value in women was 2.2 (95% CI 1.9-2.7). Moreover, in all countries, having a disadvantaged SEP is related to a higher rate of mortality from diabetes and a linear relationship is observed. Eastern European countries have higher relative inequalities in mortality by SEP. According to our data, the RR of dying from diabetes for women with low a SEP is 3.4 (95% CI 2.6-4.6), while in men it is 2.0 (95% CI 1.7-2.4).

CONCLUSIONS/INTERPRETATION

In Europe, educational attainment and diabetes are inversely related, in terms of both morbidity and mortality rates. This underlines the importance of targeting interventions towards low SEP groups. Access and use of healthcare services by people with diabetes also need to be improved.

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.

Sensitivity and specificity of death certificates for diabetes: as good as it gets?

OBJECTIVE

Diabetes is the sixth leading cause of death in U.S adults, which may be an underestimate because of under-reporting on death certificates. In this study we examined death certificate sensitivity and specificity for diabetes, as well as the factors related to better reporting, in a community-based sample.

RESEARCH DESIGN AND METHODS

Death certificates were obtained for 3,209 decedents who were enrolled in the Rancho Bernardo cohort in 1972-1974 and followed through 2003. Diabetes status was reassessed at periodic clinic visits and annual mailed surveys during an average follow-up of 15.2 +/- 7.6 years. Diabetes reported anywhere on death certificates was abstracted. Sensitivity and specificity calculations among diabetic participants were stratified by age, sex, year, place, cause of death, and diabetes medication use.

RESULTS

Among 1,641 men and 1,568 women, 378 decedents had a history of diabetes, 168 of whom had diabetes listed anywhere on their death certificates. The sensitivity and specificity were 34.7 and 98.1%. Diabetes reporting on death certificates did not improve over time or vary significantly by age and sex, but sensitivity for diabetes reporting was better for recent (1992-2003) cardiovascular disease (CVD) deaths compared with any other causes of death (48.9 vs. 28.6%, respectively, P < 0.05).

CONCLUSIONS

Although diabetes reporting on death certificates did not improve over time, sensitivity was better for diabetes in the context of CVD deaths, probably reflecting the increasing recognition that diabetes is a major cardiovascular risk factor.

Reporting of diabetes on death certificates using data from the UK Prospective Diabetes Study

AIMS

To study the effect of age at death, sex, ethnic group, date of death, underlying cause of death and social class on the frequency of reporting diabetes on death certificates in known cases of diabetes.

METHODS

Data were extracted from certificates recording 981 deaths which occurred between 1985 and 1999 in people aged 45 years or more who participated in the UK Prospective Diabetes Study, to which 23 English, Scottish and Northern Ireland centres contributed. Diabetes (9th revision of the International Classification of Diseases; ICD-9 250) entered on parts 1A-1C or 2A-2C of the death certificate was considered as reporting diabetes. Logistic regression analyses were used to determine independent factors associated with the reporting of diabetes.

RESULTS

Diabetes was reported on 42% (419/981) of all death certificates and on 46% (249/546) of those with underlying cardiovascular disease causes. Reporting of diabetes was independently associated on all death certificates with per year of age increase (OR 1.02; 95% CI 1.001-1.04, P = 0.037), underlying cause of death (non-cardiovascular causes OR 0.76; 95% CI 0.59-0.98, P = 0.035) and social class (classes I-II OR 1.00; class III OR 1.35; 95% CI 0.96-1.89, P = 0.084, classes IV-V OR 1.48; 95% CI 1.05-2.10, P = 0.027). Stratification by age, sex, and underlying cause of death also revealed significant differences in the frequency of reporting diabetes over time.

CONCLUSIONS

The rate of reporting of diabetes on cardiovascular disease death certificates remains poor. This may indicate a lack of awareness of the importance of diabetes as a risk factor for cardiovascular disease.

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

AIMS

Diabetes is associated with increased mortality in older adults, but the specific contributions of diabetes-associated clinical conditions and of increasing hyperglycaemia to mortality risk are unknown. We evaluated whether cardiovascular disease, comorbidities, or degree of hyperglycaemia, particularly severe hyperglycaemia, affected diabetes-related mortality risk in older, disabled women.

METHODS

Six-year mortality follow-up of a random sample of 576 disabled women (aged 65-101 years), recruited from the Medicare eligibility list in Baltimore (MD, USA). All-cause and cardiovascular mortality were evaluated by diabetes status: no diabetes; diabetes with mild, moderate, and severe hyperglycaemia [defined by tertiles of glycosylated haemoglobin (GHB) among women with diabetes].

RESULTS

Diabetes with mild, moderate, and severe hyperglycaemia was associated with an increased hazard rate (HR) for all-cause mortality, even after adjustment for demographics, risks for cardiovascular disease, cardiovascular and non-cardiovascular conditions, and other known mortality risks. A dose-response effect was suggested [mild hyperglycaemia, HR 1.81, 95% confidence interval (CI) 1.03, 3.17; moderate hyperglycaemia, HR 2.02, 95% CI 1.34, 3.57; severe hyperglycaemia, HR 2.22, 95% CI 1.17, 4.25]. Women with diabetes had a significantly increased HR for non-cardiovascular death, but not for cardiovascular death, compared with those without diabetes.

CONCLUSIONS

Diabetes, whether characterized by mild, moderate or severe hyperglycaemia, appears to be an independent risk factor for excess mortality in older disabled women and this risk may increase with increasing hyperglycaemia. This mortality risk is not completely explained by vascular complications, and involves non-cardiovascular deaths. Risks and benefits of diabetes management, including glycaemic control and management of vascular and other comorbidities, should be studied in older people with complications and comorbidities.

Diagnosis of type 2 diabetes at an older age: effect on mortality in men and women

OBJECTIVE

To compare the mortality of people who were diagnosed with type 2 diabetes over 65 years of age with that of nondiabetic individuals.

RESEARCH DESIGN AND METHODS

Using a population-based diabetes information system for an observational cohort study in Tayside, Scotland, people who were diagnosed with type 2 diabetes over the age of 65 years between 1993 and 2002 were identified. Nondiabetic comparators, matched for age and sex, were identified from the nondiabetic population. The two cohorts were followed up for mortality and cardiovascular mortality according to death certification records.

RESULTS

There were 3,594 people with type 2 diabetes (48% male) and 7,188 matched comparators identified in the study. Over a mean follow-up period of 4.6 +/- 2.9 years for 3,594 people with type 2 diabetes and 7,188 comparators, 909 (25.3%) patients in the diabetic cohort and 1,651 (23.0%) in the nondiabetic cohort died. The adjusted relative risk for mortality in the diabetic cohort compared with the nondiabetic cohort was 1.06 (95% CI 0.94-1.19) for men and 1.29 (1.15-1.45) for women. Cardiovascular deaths accounted for 49.4% of the deaths in people with and 45.2% in those without diabetes (adjusted relative risk 1.01 [0.93-1.10]).

CONCLUSIONS

Men diagnosed with type 2 diabetes over the age of 65 years have no excess mortality compared with their nondiabetic counterparts, a finding that was not replicated for women.

Diabetes-related morbidity and mortality in a national sample of U.S. elders

OBJECTIVE

Although the number of elders with diabetes has increased dramatically, there are few data on rates of mortality and serious complications in older populations with diabetes. To determine such rates, we conducted a population-based, nonconcurrent cohort study using claims data from the 1994-1996 Medicare 5% Standard Analytical File.

RESEARCH DESIGN AND METHODS

Codes from the ICD-9 were used to identify diabetes and the following complications: amputation, lower extremity infection, gangrene, blindness, acute myocardial infarction, ischemic heart disease, stroke, and metabolic disorders. Using these codes, we assembled a cohort of 148,562 Medicare Part A and B beneficiaries who were > or = 65 years of age, who were alive on 1 January 1995, who were not in managed care in 1994, and who had a diabetes-related claim in 1994. Age-specific rates of death and complications were then calculated.

RESULTS

During 24 months of follow-up, 22,044 (14.8%) elders with diabetes died. Death rates in men and women increased significantly with age. Compared with their counterparts in the general U.S. population, elders with diabetes suffered excess mortality at every age group, corresponding to an overall standardized mortality ratio of 1.41 (95% CI 1.39,1.43). The incidence of ischemic heart disease and stroke was 181.5 and 126.2 per 1,000 person-years, respectively, which was higher than the incidence of all other diabetes-related complications.

CONCLUSIONS

In every age group, elders with diabetes have significantly higher all-cause mortality rates than the general population. Medicare data may be useful in monitoring trends in diabetes-related morbidity and total mortality in U.S. elders with diabetes.

Incidence, prevalence, and mortality of insulin-dependent (type 1) diabetes mellitus in Lithuanian children during 1983-98

AIMS/HYPOTHESIS

Our purpose is to analyze interrelations of the incidence, prevalence and mortality of childhood-onset insulin-dependent diabetes mellitus (type 1) in Lithuania.

METHODS

Incidence and prevalence rates were based on the national type 1 diabetes register during 1983-98. The cohort study was performed to evaluate the standardized mortality ratios.

RESULTS

The average incidence of type 1 diabetes during the 16-yr study period was 7.36 per 100,000/yr. For both males and females the highest incidence of type 1 diabetes was recorded in the 10-14 yr age group. The regression-based linear trends of the increase in incidence in various age groups and the annual percentage change for both genders was 2.05 (p = 0.0039) and the greatest regression slope is observed for both genders in the 10-14 yr age group. Regression-based linear trends in type 1 diabetes prevalence indicate an even growth in all age groups (3.47; p = 0.001), although the annual percentage change is most prominent in the 5-9 yr age group for girls (4.95%/yr) and in the 10-14 yr age group for boys (4.06%/yr). The standardized mortality ratio of all-cause mortality in people with diabetes is higher than in the common population 7.71 (p < 0.0001). The standard mortality ratio for all causes increases with longer diabetes duration.

CONCLUSION/INTERPRETATION

The significant increasing trend of incidence and prevalence during 1983-98 is observed. The annual percentage change is similar. The young patients with type 1 diabetes have a higher mortality risk.

Cause-specific mortality in a population with diabetes: South Tees Diabetes Mortality Study

OBJECTIVE

To describe the mortality of a population with diabetes compared with the local nondiabetic population, using age-, sex-, and cause-specific death rates and relative and absolute differences in death rates.

RESEARCH DESIGN AND METHODS

A population-based cohort of 4,842 people with diabetes living within South Tees, U.K., was identified and followed from 1 January 1994 to 31 December 1999. Causes of death were obtained from death certificates, and mortality rates were compared with the nondiabetic population of the same area for the same time period.

RESULTS

There were 1,205 deaths (24.9%) in the study population during the 6 years of study. For type 2 diabetes, mortality from cardiovascular causes was significantly increased in both sexes and at all ages. Relative death rates for the age band 40-59 years were 5.47 (95% CI 4.18-7.15) for men and 5.60 (3.44-9.14) for women. The relative death rates declined with age for both sexes, but absolute excess mortality increased with age. There were no consistent differences in noncardiovascular death rates, other than for renal disease. Similar outcomes were found for type 1 diabetes, although these results were limited by a much smaller population size. People with diabetes and renal impairment had significantly higher mortality than people with diabetes alone, with a rate ratio of 7.27 for people with type 2 diabetes aged 40-59 years.

CONCLUSIONS

In an area of the U.K. with high cardiovascular death rates, people with diabetes had significantly higher cardiovascular death rates than people without diabetes. Interventions targeted at cardiovascular risk factors should be used to try and reduce this excess premature mortality, which is especially high in those with renal impairment.

Excess mortality in a population with diabetes and the impact of material deprivation: longitudinal, population based study

OBJECTIVES

To establish the age and sex specific mortality for people with diabetes in comparison with local and national background populations; to investigate the relationship between mortality and material deprivation in an unselected population with diabetes.

DESIGN

Longitudinal study, using a population based district diabetes register.

SETTING

South Tees, United Kingdom.

PARTICIPANTS

All people known to have diabetes living in Middlesbrough and Redcar and Cleveland local authorities on 1 January 1994.

MAIN OUTCOME MEASURE

Death, from any cause, between 1 January 1994 and 31 December 1999.

RESULTS

Over the six years of the study 1205 (24.9%) of 4842 participants died. All cause standardised mortality ratios for type 1 diabetes were 641 (95% confidence interval 406 to 962) in women and 294 (200 to 418) in men, and those for type 2 diabetes were 160 (147 to 174) in women and 141 (130 to 152) in men. Cause specific standardised mortality ratios were increased for ischaemic heart disease, cerebrovascular disease, and renal disease; no reductions in mortality from other causes were seen. The risk of premature death increased significantly with increasing material deprivation (P<0.001).

CONCLUSIONS

Diabetes is associated with excess mortality, even in an area with high background death rates from cardiovascular disease. This excess mortality is evident in all age groups, most pronounced in young people with type 1 diabetes, and exacerbated by material deprivation. Aggressive approaches to the management of cardiovascular risk factors could reduce the excess mortality in people with diabetes.

Non-dipping circadian blood pressure and renal impairment are associated with increased mortality in diabetes mellitus

AIMS

To assess the relevance of circadian blood pressure variation to future morbidity and mortality in patients with diabetes mellitus.

METHODS

A retrospective descriptive 4 year follow-up study of data collected after ambulatory blood pressure monitoring in a clinic setting.

RESULTS

Seventy-five patients (46 male; 29 female) of whom 41 % had Type 1 diabetes and 59% Type 2 were followed up for a median of 42 months (11-56). The median creatinine for the whole group at baseline was 101 (56-501) micromol/l. The median circadian blood pressures for the total study population were 147 (110-194)/87 (66-109) mmHg during daytime and 132 (86-190)/77 (50-122) mmHg during night-time. Half of the patients exhibited a fall in night-time pressures to 10% lower than daytime pressures (dippers). Dippers were younger, 47 (32-75) years, than non-dippers, 57 (35-79) years, P = 0.03. Over time, dippers had a lower mortality than non-dippers, with 8% deaths in the cohort of dippers, 26% deaths in the cohort of non-dippers, P = 0.04. Cox regression analysis revealed significant contributions from age, duration of diabetes and baseline renal function to subsequent mortality in non-dippers. Analysing current degree of renal impairment and original dipper status together revealed that, of those patients whose creatinine remained normal, 7% of patients whose blood pressure dipped had subsequently died and 10% of non-dipping patients had died; of those patients whose creatinine unequivocally rose, 10% of dipping patients had died and 42% of non-dipping patients had died, P = 0.03

CONCLUSIONS

Loss of circadian variation in blood pressure is associated with an increased mortality rate, regardless of diabetes type. The combination of non-dipping and subsequent renal impairment leads to the highest mortality rate. The study suggests a role for ambulatory blood pressure monitoring in day-to-day clinical practice to select patients with nephropathy who are at greatest risk, in an effort to alter outcome.

Showing neuropathy is related to increased mortality in diabetic patients - a survival analysis using an accelerated failure time model

Diabetic subjects still have a reduced life expectancy despite many potential advances in patient care. Furthermore, population-based studies in well-defined cohorts of patients, to investigate the reduced life expectancies, are generally lacking. Computerized baseline data on a cohort of diabetic patients first attending our clinic during 1982-1985 were used to identify risk factors for increased mortality. This was carried out using an accelerated failure time (ACF) model. Out of 794 patients entered into the model, 201 (25.3%) patients died between 1982 and 1995. Baseline microvascular diabetic complications (peripheral sensory neuropathy and nephropathy) were found to be associated with increased mortality in patients, indicating that these are important, often overlooked, markers for those at greatest risk. Patients with type I (insulin dependent) diabetes mellitus were also identified as being at greater risk.

Causes of death in children with insulin dependent diabetes 1990-96

BACKGROUND

Mortality rates in children with insulin dependent diabetes (IDDM) in the UK are unknown and the causes of death not well documented.

AIM

To determine the mortality rate and causes of death in children with IDDM.

METHODS

The Office of National Statistics (England and Wales) and the General Register Office (Scotland) notified all deaths under 20 years of age from 1990 to 1996 with diabetes on the certificate. Further details were provided by coroners, pathologists, and clinicians.

RESULTS

116 deaths were notified and 83 were caused by diabetes. The standardised mortality ratio was 2.3 (95% confidence interval (CI), 1.9 to 2.9), being highest in the age group 1-4 years, at 9.2 (95% CI, 5.4 to 14.7). Of the 83 diabetic deaths, hyperglycaemia/diabetic ketoacidosis (DKA) was implicated in 69 and hypoglycaemia in 7. Cerebral oedema was the most common cause of death in young children (25 of 36 diabetes related deaths in children under 12 years of age). 34 young people (10-19 years; 24 male) were either found dead at home (n = 26) or moribund on arrival at hospital (n = 8). In 24 of these, it appeared that DKA was the cause of death, in four hypoglycaemia was likely. Nine of these were found "dead in bed".

CONCLUSIONS

Children with IDDM have a higher mortality than the general population. Cerebral oedema accounts for most hospital deaths in young children. There are a large number of young men dying at home from neglected IDDM. Early diagnosis of IDDM in children and closer supervision of young people might prevent some of these deaths.

Incidence and determinants of mortality and cardiovascular events in diabetes mellitus: a meta-analysis

Patients with diabetes mellitus are at increased risk of developing atherosclerotic disease. The extent of this additional risk and its determinants are not well known, but this information is needed for sample-size estimations in intervention studies. Therefore, a meta-analysis of epidemiologic studies on this subject was performed. Medline was searched from 1966 onwards, including the reference lists of all relevant publications. A total of 27 prospective follow-up studies in the English language that allowed calculation of the unadjusted incidence of one of the predefined outcome events were included. The influence of age, sex, type of diabetes, duration of diabetes, year of study, HbA1c, cholesterol level, blood pressure and smoking on these incidences was studied by means of univariate Poisson regression analysis. Overall total mortality was 2.9% per year (95% CI 2.8-3.0; 27 studies), and for death from all vascular causes was 1.4% per year (95% CI 1.3-1.4; 16 studies). Only two studies were found that reported on the incidence of the composite outcome 'event death from all vascular causes, non-fatal myocardial infarction, or non-fatal stroke'. In univariate analysis, age, year of study, total cholesterol and systolic blood pressure were positively related to total mortality and death from all vascular causes. After adjustment for age, or limiting the analyses to studies in patients with type 2 diabetes only (n = 11), these relationships remained statistically significant. In conclusion, the overall yearly total mortality in diabetes mellitus is 2.9% and for death from all vascular causes is 1.4%. There are few data on the incidence of composite cardiovascular outcome events.

The British Diabetic Association Cohort Study, I: all-cause mortality in patients with insulin-treated diabetes mellitus

AIMS

To assess mortality in patients with diabetes incident under the age of 30 years.

METHODS

A cohort of 23 752 diabetic patients diagnosed under the age of 30 years from throughout the United Kingdom was identified during 1972-93 and followed up to February 1997. Following notification of deaths during this period, age- and sex-specific mortality rates, attributable risks and standardized mortality rates were calculated.

RESULTS

The 23 752 patients contributed a total of 317 522 person-years of follow-up, an average of 13.4 years per subject. During follow-up 949 deaths occurred in patients between the ages of 1 and 84 years, 566 in males and 383 in females. All-cause mortality rates in the patients with diabetes exceeded those in the general population at all ages and within the cohort were higher for males than females at all ages except between 5 and 15 years. The relative risk of death (standardized mortality ratio, SMR), was higher for females than males at all ages, being 4.0 (95% CI 3.6-4.4) for females and 2.7 (2.5-2.9) for males overall, but reaching a peak of 5.7 (4.7-7.0) in females aged 20-29, and of 4.0 (3.1-5.0) in males aged 40-49. Attributable risks, or the excess deaths in persons with diabetes compared with the general population, increased with age in both sexes.

CONCLUSIONS

This is the first study from the UK of young patients diagnosed with diabetes that is large enough to calculate detailed age-specific mortality rates. This study provides a baseline for further studies of mortality and change in mortality within the United Kingdom.

The British Diabetic Association Cohort Study, II: cause-specific mortality in patients with insulin-treated diabetes mellitus

AIMS

To measure cause-specific mortality, by age, in patients with insulin-treated diabetes incident at a young age.

METHODS

A cohort of 23 752 patients with insulin-treated diabetes diagnosed under the age of 30 years, from throughout the United Kingdom, was identified during 1972-93 and followed to February 1997. Death certificates have been obtained for deaths during the follow-up period and cause-specific mortality rates and standardized mortality ratios by age and sex are reported.

RESULTS

During the follow-up period 949 deaths occurred and at all ages mortality rates were considerably higher than in the general population. Acute metabolic complications of diabetes were the greatest single cause of excess death under the age of 30 years. Cardiovascular disease was responsible for the greatest proportion of the deaths from the age of 30 years onwards.

CONCLUSIONS

Deaths in patients with diabetes diagnosed under the age of 30 have been reported and comparisons drawn with mortality in the general population. To reduce these deaths attention must be paid both to the prevention of acute metabolic deaths and the early detection and treatment of cardiovascular disease and associated risk factors.

Causes of death and associated factors among patients with non-insulin-dependent diabetes mellitus in Taipei, Taiwan

A cohort of 766 patients with non-insulin-dependent diabetes mellitus (NIDDM) from a general teaching hospital in Taipei, Taiwan were followed prospectively to assess survival experience and associated risk factors. Data were abstracted from the medical records and additional information was obtained from patients or their closest relatives using a structured questionnaire. Date and cause of death were determined from death certificates. Standardized mortality ratios were calculated by the direct method. Chi2-Square test and Cox's proportional hazard analysis were used to control for potential confounders. During a median follow-up of 3.5 years (range 1 month to 4.6 years), 131 deaths occurred. Of these, 29.8% were due to cardiopulmonary disease (ICD 401-429), 13.0% due to cerebrovascular disease (ICD 430-438), 13.0% due to acute diabetes metabolic complications (250.1, 250.2), and 11.4% due to nephropathy (580-589). Adjusted for age, people with NIDDM had 2.2 (95% CI 1.6-2.9) times the risk of death than members of the general population, and cause-specific standardized mortality ratios were: CPD 4.6, nephropathy 8.8, cerebrovascular disease 1.9, and neoplasm 0.7. Age, fasting plasma glucose, hypertension, and proteinuria were positively and independently associated with all-cause mortality (P < 0.05 for each). Thus, NIDDM patients have higher mortality rates than the general population in Taiwan, and age, fasting plasma glucose, hypertension, and proteinuria are associated with this excess risk. Proper application of available interventions may control these factors with a consequent reduction in mortality. Particular attention is needed to prevent deaths from the acute metabolic complications of diabetes.

Relationship between blood glucose level and mortality in type 2 diabetes mellitus: a systematic review

AIM

To review the relationship between blood glucose level and mortality in patients with Type 2 diabetes mellitus (DM) as reported in the literature.

METHODS

Literature search using Medline Search: January 1966 - April 1998.

KEYWORDS

Diabetes, Non Insulin Dependent, Mortality. Inclusion criteria for papers were: Type 2 DM; follow-up for at least 3 years; glucose or glycated haemoglobin (HbA1c) was used as parameter; published in the form of an article. Additionally all references in the selected articles that dealt with the relationship between blood glucose level and mortality in Type 2 DM were included in the search.

RESULTS

Twenty-seven eligible articles were found. Twenty-three of them showed a positive association: measures of elevated blood glucose concentrations were associated with higher mortality; in 15 out of 23 studies the positive association was statistically significant, in two only for postprandial blood glucose. One study found a nonsignificant negative relationship in a very old population.

CONCLUSION

In the literature there is a positive, but rather weak, association between the measures of blood glucose control and the risk of dying of patients with Type 2 DM. In the six larger studies (more than 100 deceased patients) that used a continuous categorization of glycaemia, the Risk ratio per unit varies from 1.03 to 1.12.

Coronary heart disease mortality amongst non-insulin-dependent diabetic subjects in Iceland: the independent effect of diabetes. The Reykjavik Study 17-year follow up

OBJECTIVES

The main aim of this study was to estimate the independent risk for coronary heart disease (CHD) death associated with non-insulin dependent (Type 2) diabetes (NIDDM) and effect on life expectancy.

DESIGN AND SETTING

The Reykjavik Study is a prospective cardiovascular population study which started in 1967. A randomized selection procedure identified individuals for invitation to participate, based on their year and date of birth. Participants were examined in the years 1967-91 in one research clinic in Reykjavik.

SUBJECTS AND METHODS

The population in this survey were Icelandic Caucasian males and females, born 1907-35 and therefore 34-79 years old when their examination was performed. Altogether 9139 males and 9773 females attended, and of those 267 males and 210 female were NIDDM as defined by a questionnaire or an oral glucose tolerance test. Other factors measured in the study included systolic and diastolic blood pressure, fasting total cholesterol, triglycerides, uric acid, smoking habits, height, and weight. The causes of death were determined by a review of all death certificates. Results. The relative risk of death from CHD (95% confidence limits), independently associated with NIDDM, was 2.0 (1.5-2.6) for males and 2.4 (1.6-3.6) for females. The relative risk of death from all causes was 1.9 (1.6-2.3) and 1.7 (1.3-2.1), respectively, for male and female diabetic patients.

CONCLUSIONS

Non-insulin dependent diabetes mellitus carried twice the risk of CHD death in both sexes, independently of other risk factors. The diagnosis of NIDDM at the age 55 years reduced an individual's life expectancy by about five years, mostly because of increased CHD death rate.

Mortality in a large population-based cohort of patients with drug-treated diabetes mellitus

OBJECTIVES

This paper presents detailed cause-specific data about excess mortality among diabetic persons in Finland, by age and sex.

METHODS

Five-year follow-up data on the Finnish population aged 30 through 74 years were analyzed. During these 5 years, 11,215 persons with diabetes and 102,843 persons without diabetes died. The diabetic population was defined as people who were entitled to free medication for diabetes at the beginning of the follow-up period, that is, at the end of 1980.

RESULTS

The relative mortality of persons with drug-treated diabetes compared with nondiabetic persons was higher among women (3.4) than among men (2.4). Almost three quarters of the mortality excess was due to circulatory diseases. For most other causes of death, too, diabetic persons had higher than average mortality. The exceptions were lung cancer, chronic obstructive pulmonary disease, and alcohol poisoning.

CONCLUSIONS

Diabetes is a general risk factor for untimely death and makes a significant contribution to overall national death rates, particularly for circulatory diseases. Lower than average mortality from smoking-related diseases and alcohol poisoning, however, warrant optimism about the effects of health education among diabetic persons.

Mortality experience of Navajos with type 2 diabetes mellitus

OBJECTIVES

We sought to determine the contribution of type 2 diabetes mellitus to mortality in a Navajo population, and to assess the impact of pre-existing coronary heart disease on this relationship.

METHODS

A cohort of 77 Navajos with type 2 diabetes mellitus and 77 non-diabetic controls matched on age, gender and community of residence were followed for an 18-year period, from 1974 to 1992.

RESULTS

The vital status of 152 of the 154 study subjects was ascertained at 18-year follow-up. There were 30 deaths (39%) in the type 2 diabetes group and 13 (17%) in the control group during the 18-year period which was significantly different in bivariate matched pairs analysis (risk ratio = 3.12, McNemar's chi 2 = 7.76, p < 0.01). Multivariate conditional logistic response models (risk ratio = 3.02, 95% CI 1.21, 7.53) and stratification analysis (McNemar's Summary chi 2 = 8.05, 2 df, p < 0.05), confirmed that survival was significantly different for the two groups, even when controlling for baseline cardiovascular comorbidity and hypertension.

CONCLUSION

These data describe the mortality impact of the epidemic of type 2 diabetes and cardiovascular disease now accelerating among the Navajo. The significant mortality differences between the diabetes and non-diabetes groups and the continuing rise in prevalence of type 2 diabetes underscore the need for an effective community-based approach to diabetes prevention among the Navajo.

Over-mortality as related to age and gender in patients with established non-insulin-dependent diabetes mellitus

In 1981-1982, 5699 persons representing 92.9% of the total population aged 60-74 years living in Fredericia, Denmark, were interviewed about a possible history of diabetes and had a fasting blood glucose measured. A total of 236 gave a positive history of diabetes; 88 had one fasting blood glucose of 7 mmol/L or more. For each of these probands, an age- and gender-matched control person with normal fasting blood glucose and no history of diabetes was selected randomly. Of the 236, 91.5% had NIDDM as judged by glucagon-stimulated C-peptide tests. At the end of December 1995, the participants were traced through the National Register and their status (alive or dead) was determined. The date of death was confirmed. The median observation time from screening and inclusion in the study till death or the end of the observation period in December 1995 was 12.81 years, the maximum was 14.91, and the 25th and 75th percentile values were 6.36 and 13.94 years, respectively. At the end of 1995, 165 (74.4%) of 228 persons with known diabetes at the time of ascertainment had died opposed to 90 (40.4%) of the 223 nondiabetic control persons. The difference is statistically highly significant (p < 0.00001, log-rank test). Within the first 5 years of observation, 42.9% of diabetic men died and only 22.5% of non-diabetic men. This percentage of deaths in diabetic men was found already in the 60-64 year age interval (46.2%). The mortality rate for the non-diabetic population seems to increase later. After 13 years of observation, 74 (81.3%) of 91 men with known diabetes had died, in the age-matched control men, 50 (56.2%) of 89 (p = 0.00006). Ninety-one (66.4%) of 137 diabetic women had died: 40 (29.9%) of 134 control women (p < 0.00001). The difference between mortality in diabetic men and women, and between nondiabetic men and women is highly significant (p = 0.00285 and 0.00001, respectively). The over-mortality of established diabetic persons decreases with age. In the age group 60-74 years, the over-mortality is about 2.5 without gender difference.

Cardiovascular mortality and morbidity in type-2 diabetes mellitus

A representative number of prospective studies clearly indicate that cardiovascular morbidity and mortality is significantly increased in type-2 diabetic patients in comparison with non-diabetic control subjects. The cardiovascular death rate is 4.4 fold increased in those diabetic patients presenting none of the classical risk factors (hypertension, hypercholesterinemia or smoking) compared with age-matched control subjects (MRFIT). A decreased survival rate after myocardial infarction, congestive heart failure and an increased occurrence of silent ischemia are responsible for the poor prognosis of type-2 diabetic patients. Recent studies indicate that haemostatic abnormalities and endothelial dysfunction are important risk factors for coronary events in diabetic as well as in nondiabetic patients. In newly diagnosed type-2 diabetic patients a similar prevalence of myocardial infarction and angina compared to previously known type-2 diabetes was found. The long prediabetic period and clustering of risk factors may be very relevant for the high prevalence of cardiovascular disease already at diagnosis of type-2 diabetes. More recent studies performed in Scotland and Verona demonstrated a mortality risk approximately only 50% higher than in nondiabetic subjects. The reduction in the mortality risk could reflect an improvement in diabetes prognosis from the 1960s to the 1980s. Recent observations in type-2 diabetic patients from Finland indicate that glycemic control is an important predictor for coronary heart disease morbidity and mortality. However incidence of coronary heart disease is only low in those patients presenting with a HbAlc value below 6.0%. More information will be available after analysis of the United Kingdom prospective diabetes study. (UKPDS).

Three years' experience after national introduction of teaching programs for type II diabetic patients in Germany: how to train general practitioners

Beginning in July 1991, office-based physicians in Germany were remunerated for providing a structured treatment and teaching program to non-insulin-treated type II diabetic patients. The treatment and teaching program is based upon the respective recommendations of the German Diabetes Association. This article describes the structure of the program and the courses for general practitioners and their nurses. The prospective studies proving the beneficial effects of the program are summarized.

The Verona diabetes study: a population-based survey on known diabetes mellitus prevalence and 5-year all-cause mortality

This population-based survey aimed to determine the prevalence of known diabetes mellitus on 31 December 1986, and to assess all-cause mortality in the subsequent 5 years (1987-1991) in Verona, Italy. In the study of prevalence, 5996 patients were identified by three independent sources: family physicians, diabetes clinics, and drug prescriptions for diabetes. Mortality was assessed by matching all death certificates of Verona in 1987-1991 with the diabetic cohort. Overall diabetes prevalence was 2.61% (95% confidence interval 2.56-2.67). Prevalence of insulin-dependent and non-insulin-dependent diabetes mellitus was 0.069% (0.059-0.078) and 2.49% (2.43-2.54), respectively. Diabetes prevalence sharply increased after age 35 years up to age 75-79, and finally declined. Prevalence was higher in men up to age 69 years, in women after age 75 years. Of the diabetic cohort 1260 patients (592 men, 668 women) died by 31 December 1991, yielding an overall standardized mortality ratio of 1.46 (CI 1.38-1.54). Even though the differences narrowed with age, mortality rates in the diabetic cohort were higher than in the non-diabetic population at all ages. Women aged 65-74 years showed observed/expected ratio higher than men (2.27, CI 1.92-2.66, vs 1.50, CI 1.30-1.72), while in other age groups the sex-related differences were not significant. Pharmacological treatment of diabetes was associated with an excess mortality, while treatment with diet alone showed an apparent protective effect on mortality (observed/expected ratio 0.73, CI 0.58-0.92).(ABSTRACT TRUNCATED AT 250 WORDS)

Mortality in diabetic subjects: an eleven-year follow-up of a community-based population

In 1979, all the known diabetic subjects (849) were identified from a community (population 81851), of whom 717 (85%) were reviewed by a single observer. Using the NHS Central Register, follow-up was completed for 98% of subjects. After 11 years, 306 (42.7%) diabetic subjects had died, of whom 65 were insulin treated and 241 were non-insulin treated. Circulatory disease accounted for 168 (54.9%) deaths, of which 124 (73.8%) were due to ischaemic heart disease. The standardized mortality ratio (SMR) for all causes of death, based on data from England and Wales, was significantly raised for both insulin-treated and non-insulin-treated patients (1.75, 95% CI 1.35 to 2.24 and 1.32, 95% CI 1.15 to 1.50, respectively). SMRs for all cause mortality were significantly greater for diabetic subjects in the 45-64 (SMR, 1.97, 95% CI 1.34 to 2.80), 65-74 (SMR 1.59, 95% CI 1.27 to 1.97 and 75 years and over (SMR 1.26, 95% CI 1.08 to 1.45) age ranges. Using a proportional hazards model, after adjusting for age and gender, systolic blood pressure and vibration threshold were significant predictors of all cause mortality in insulin-treated subjects. For non-insulin-treated subjects, blood glucose, systolic blood pressure, glycated haemoglobin, retinopathy, proteinuria, coronary artery disease, and stroke were significant baseline predictors of mortality. No association was found for serum cholesterol, body mass index, diastolic pressure or cigarette smoking in either treatment group.

Trends in coded causes of death following definite myocardial infarction and the role of competing risks: the Minnesota Heart Survey (MHS)

We investigated possible differences over time in underlying causes of death among validated definite myocardial infarction cases who were discharged following an index hospitalization in 1970, 1980, and 1985 in the Twin Cities, MN. No changes were observed in underlying causes of death assigned to patients who died prior to discharge in the 3 years. Among in-hospital survivors of definite MI, however, age-adjusted rates of death from non-cardiovascular causes more than doubled between 1970 and 1985 (P < 0.01). More specifically, mortality rates for diabetes mellitus increased significantly from 1970 to 1985 (P < 0.05), while those for neoplasms and diseases of the respiratory system increased non-significantly. Whether these data are the result of artifactual changes in cause of death assignment or real changes in disease severity and comorbidity, these trends in long-term death following acute MI may have had a modest impact on reported community-wide coronary heart disease mortality rates.

The mortality of elderly people with diabetes

To assess the full effect of diabetes on survival in elderly subjects, residents of Melton Mowbray aged 65, 70, 75, 80, and 85 years were screened by glucose tolerance test and followed up for 4.5 years. Death occurred in 56 of 520 normal subjects, 9 of 44 subjects with impaired glucose tolerance, 7 of 19 newly diagnosed diabetic subjects, and 27 of 52 known diabetic subjects. Diabetic subjects were 4.5 times (95% confidence interval 2.9-7.0) more likely to die than subjects with normal glucose tolerance. Thus elderly diabetic subjects have a substantially increased risk of death compared to their normal glucose tolerant peers.

Lipoprotein disorders in diabetes mellitus

In IDDM or NIDDM, the total plasma cholesterol and triglycerides are usually within normal limits when the blood glucose is controlled. Marked hypertriglyceridemia can develop with loss of glycemic control and is often due to superimposed genetic abnormalities in lipoprotein metabolism. Tight control in IDDM usually reduces LDL and VLDL to normal levels and may raise HDL above the normal range. Low HDL cholesterol and mild to moderate elevations of VLDL triglyceride are common in NIDDM if obesity or proteinuria is also present. Both HDL and LDL may be smaller and more dense and may be enriched with triglyceride as compared with cholesterol. These abnormalities may require weight loss for control. The increased incidence of cardiovascular disease in diabetes is unexplained but is amplified by the well-defined cardiovascular risk factors. The new American Diabetes Association guidelines call for treatment of high triglycerides and LDL cholesterol to be aggressively reduced. Triglycerides should be under 200 mg/dL, are considered borderline high between 200 and 400 mg/dL, and high when above 400 mg/dL. Low HDL is defined as less than 35 mg/dL. Control of obesity with diet and exercise and reduced intake of saturated fat and cholesterol are important first steps. If needed, drug therapy is appropriate to reduce LDL to levels below 130 mg/dL in all adult diabetics and below 100 mg/dL in those with cardiovascular disease.

Cause-specific mortality: understanding uncertain tips of the disease iceberg

STUDY OBJECTIVE

To determine the extent to which individual diseases, when recorded as being present shortly before death, were certified as causes of death.

DESIGN

Retrospective cohort study in which the "subjects" were computerised linked records.

SETTING

Six districts in the Oxford Regional Health Authority area (covering a population of 1.9 million people).

SUBJECTS

Linked abstracts of hospital records and death certificates for people who died within four weeks and, for some diseases, within one year of hospital admission.

MAIN OUTCOME MEASURES

The percentage of people with each disease for whom the disease was recorded as the underlying cause of death, was recorded elsewhere on the death certificate, or was not certified as a cause of death at all.

RESULTS

Three broad patterns of certification are distinguished. Firstly, there were diseases that were usually recorded on death certificates when death occurred within four weeks of hospital care of them. Examples included lung cancer (on 91% of such death certificates), breast cancer (92%), leukaemia and lymphoma (90%), anterior horn cell disease (89%), multiple sclerosis (89%), myocardial infarction (90%), stroke (93%), aortic aneurysm (87%), and spina bifida (89%). These diseases were also usually certified as the underlying cause of death. Secondly, there were diseases which, when present within four weeks of death, were commonly recorded on death certificates but often not as the underlying cause of death. Examples included tuberculosis (on 76% of such certificates; underlying cause on 54%), thyroid disease (49%; 21%), diabetes mellitus (69%; 30%) and hypertension (43%; 22%). Thirdly, there were conditions which, when death occurred within four weeks of their treatment, were recorded on the death certificate in a minority of cases only. Examples of these included fractured neck of femur (on 25% of such certificates), asthma (37%), and anaemia (22%). Not surprisingly, there was "convergence" in certification practice towards the common cardiovascular and respiratory causes of death. There was also evidence that conditions regarded as avoidable causes of death may not have been certified when present at death in some patients.

CONCLUSION

When uses are made of mortality statistics alone, it is important to know which category of certification practice the disease of interest is likely to be in. Linkage between morbidity and mortality records, and multiple cause analysis of mortality, would considerably improve the ability to quantify mortality associated with individual diseases.

Mortality among type 2 diabetic individuals and associated risk factors: the Three City Study

The 10 year mortality experience was determined in a population-based cohort of 540 Type 2 diabetic individuals. The association between potential risk factors and all causes mortality was examined. Diabetes was not mentioned anywhere on the death certificate in 46% of 274 decedents. Diseases of the circulatory system (ICD9-390-459) accounted for the majority (62%) of deaths in this cohort. Ten-year survival was poorer than expected for both men and women compared to the age- and sex-matched Minnesota population. Standardized mortality ratios for selected causes of death indicated excess for cardiovascular disease (ICD9-390-459), coronary heart disease (ICD9 410-414) and cerebrovascular disease. Baseline variables associated with all causes of mortality included age and a history of macrovascular disease. These findings indicate that mortality data significantly underestimate the magnitude of diabetes and that individuals with diabetes have poorer survival than non-diabetic individuals.

Diabetes mellitus, impaired glucose tolerance and mortality among elderly men: the Finnish cohorts of the Seven Countries Study

We studied the association of glucose intolerance with total and cause-specific mortality during a 5-year follow-up of 637 elderly Finnish men aged 65 to 84 years. Total mortality was 276 per 1000 for men aged 65 to 74 years and 537 per 1000 for men aged 75 to 84 years. Five-year total mortality adjusted for age was 364 per 1000 in diabetic men, 234 per 1000 in men with impaired glucose tolerance and 209 per 1000 in men with normal glucose tolerance. The relative risk of death among diabetic men was 2.10 (95% confidence interval 1.26 to 3.49) and among men with impaired glucose tolerance 1.17 (95% confidence interval 0.71 to 1.94) times higher compared with men with normal glucose tolerance. Cardiovascular disease was the most common cause of death in every glucose tolerance group. The multivariate adjusted relative risk of cardiovascular death was increased (1.55) in diabetic patients, albeit non-significantly (95% confidence interval 0.84 to 2.85). Diabetes resulted in an increased risk of cardiovascular mortality among men aged 65-74 years but not among the 75- 84-year-old men. Relative risk of death from non-cardiovascular causes was slightly increased among diabetic subjects. In conclusion, diabetes mellitus is a significant determinant of mortality among elderly Finnish men.

The management of diabetes mellitus in older individuals

Nearly 50% of individuals with type II diabetes mellitus are over the age of 65 years. There are numerous reasons to maintain blood glucose levels below 11.1 nmol/L (200 mg/dl) in older persons, and there are a number of changes often seen with advancing age that persons, and there are a number of changes often seen with advancing age that may interfere with the management of diabetes mellitus, e.g. hypodipsia, anorexia, visual disturbance, altered renal and hepatic function, depression, impaired basoreceptor response and multiple medications. Hyperglycaemia appears to produce cognitive impairment which may lead to poor compliance. It is often difficult to manipulate diet in older people, and in fact dietary changes can lead to severe protein energy malnutrition. High maximum voluntary oxygen intake has been correlated with increased glucose disposal, but there is little evidence that physical exercise can improve diabetic control in the elderly. Oral sulphonylurea hypoglycaemic agents are extremely useful in the treatment of diabetes in these patients, but it should be remembered that they are more liable to develop hypoglycaemia than are younger diabetics. The role of metformin in the management of older diabetic patients is poorly studied. Many older persons can cope well with insulin therapy, but those with visual disturbances often make errors when drawing up insulin and require special attention. Combination therapy of insulin with oral hypoglycaemic agents is not recommended in this group of patients, and serum fructosamine is preferred to glycated haemoglobin to monitor control. Successful management of elderly diabetic patients thus requires an interdisciplinary team approach.

Mortality in diabetes mellitus: experience of a geographically defined population

A population-based cohort study identified 915 deaths in 4186 patients with diabetes mellitus over a 5-year period. Ischaemic heart disease, cerebrovascular disease and malignant neoplasms were the major causes of death and accounted for 40%, 16%, and 14% of deaths, respectively, compared with 27%, 14%, and 25% of deaths in the non-diabetic population. Diabetic patients had a standardized mortality ratio (SMR) of 1.15 (95% Cl 1.08-1.22) (p less than 0.001). This excess risk of death was largely due to the excess death from ischaemic heart disease (SMR 1.55 (1.40-1.71); p less than 0.001) and the impact was greatest in middle-aged female patients. Stroke mortality was not significantly increased (SMR 1.09 (0.92-1.29)) while cancer mortality was reduced (SMR 0.75 (0.63-0.89); p less than 0.01). Death rates in diabetic male patients (SMR 1.04 (0.96-1.13)) did not differ significantly from those in non-diabetic male patients because the increased risk of ischaemic heart disease deaths (SMR 1.41 (1.22-1.62); p less than 0.001) was offset by the reduced risk of deaths from malignant neoplasms (SMR 0.65 (0.51-0.82); p less than 0.001). The reduction in cancer mortality did not reach statistical significance in diabetic women (SMR 0.82 (0.64-1.05)). Diabetic nephropathy and metabolic disasters were uncommon as causes of death.

The high risk of death by alcohol related diseases in subjects diagnosed as diabetic and impaired glucose tolerant: the Paris Prospective Study after 15 years of follow-up

The 15 year mortality rates and causes of death are reported for the Paris Prospective Study cohort of 7180 working men, aged between 44 and 55 years who attended the first follow-up examination. All subjects were classified as normoglycaemic, impaired glucose tolerant or diabetic according to the WHO criteria, following an oral glucose tolerance test. The relative risks of death in comparison to the normoglycaemic group were 1.6 for impaired glucose tolerant and 2.3 for diabetic subjects; for death due to coronary heart disease: 1.7 and 2.3 respectively; for death due to alcohol and cirrhosis: 7.0 and 13.3 respectively. It appears that in this cohort a proportion of subjects screened as diabetic have impaired liver function and disturbed carbohydrate metabolism, due to excessive alcohol consumption. Alcohol should be investigated as a possible risk factor for diabetes, particularly in epidemiological studies where diabetes is diagnosed by the oral glucose tolerance test and the population has a high consumption of alcohol.

International variations in mortality among diabetic patients: the WHO Multinational Study of Vascular Disease in Diabetics

Mortality among 4740 diabetic men and women aged 35-55 years participating in the WHO Multinational Study of Vascular Disease in Diabetics has been studied. Ten of the original centres (Warsaw, Berlin, Havana, Arizona, Oklahoma, Hong Kong, Switzerland, London, Tokyo, Zagreb) were able to identify the life/death status of their study participants on 1 January 1983, giving an average follow-up period of six to seven years. All-cause mortality rates in males varied about threefold among the ten participating centres with the highest rates in Warsaw, Berlin and Havana and the lowest rates in Tokyo and Zagreb. All-cause mortality rates for females varied about fourfold with the highest rates in Warsaw and Oklahoma and the lowest rates in Tokyo. The proportion of deaths ascribed to circulatory disease varied among the centres ranging from 32% for males and 0% for females in Tokyo to 67% for males and 47% for females in London. There was an excess all-cause mortality in males compared to females for all centres except Zagreb. This excess also applied to circulatory diseases in general, ischaemic heart disease in particular and occurred in both insulin-dependent and non-insulin-dependent diabetic patients. Death rates for insulin-dependent diabetic patients were generally higher than those for non-insulin-dependent patients.

Deaths from diabetes are under-reported in national mortality statistics

Subjects with diabetes who attended rural surveys in Western Australia from 1978 to 1982 were followed up to ascertain death rates and the causes of death recorded on death certificates. Cardiovascular disease was assigned as the direct cause of death in 63% of deaths, with equal rates in male and female subjects, and renal disease in 8% of deaths with the proportion in women (12%) being greater than that in men (4%). The diagnosis of diabetes was stated on only 65% of the death certificates, and in only 24% was diabetes recorded as a direct or antecedent cause. In the same cohort the Australian Bureau of Statistics coded diabetes as the underlying cause of death in 24%, while attributing deaths to cardiovascular disease in 50% of the cases. This study suggests that diabetes is considerably underreported both on doctors' death certificates and in the mortality figures of the Australian Bureau of Statistics.