Cancer incidence and mortality in 23 000 patients with type 1 diabetes in the UK: Long-term follow-up

Type 2 diabetes is associated with raised risk of several cancers, but for type 1 diabetes risk data are fewer and inconsistent We assembled a cohort of 23 473 UK patients with insulin-treated diabetes diagnosed at ages <30, almost all of whom will have had type 1 diabetes, and for comparison 5058 diagnosed at ages 30 to 49, of whom we estimate two-thirds will have had type 2, and followed them for an average of 30 years for cancer incidence and mortality compared with general population rates. Patients aged <30 at diabetes diagnosis had significantly raised risks only for ovarian (standardised incidence ratio = 1.58; 95% confidence interval 1.16-2.11; P < .01) and vulval (3.55; 1.94-5.96; P < .001) cancers, with greatest risk when diabetes was diagnosed at ages 10-14. Risks of cancer overall (0.89; 0.84-0.95; P < .001) and sites including lung and larynx were significantly diminished. Patients diagnosed with diabetes at ages 30 to 49 had significantly raised risks of liver (1.76;1.08-2.72) and kidney (1.46;1.03-2.00) cancers, and reduced risk of cancer overall (0.89; 0.84-0.95). The raised ovarian and vulval cancer risks in patients with type 1 diabetes, especially with diabetes diagnosed around pubertal ages, suggest possible susceptibility of these organs at puberty to metabolic disruption at diabetes onset. Reduced risk of cancer overall, particularly smoking and alcohol-related sites, might reflect adoption of a healthy lifestyle.

Screening for type 2 diabetes: a short report for the National Screening Committee

BACKGROUND

The prevalence of type 2 diabetes mellitus (T2DM) has been increasing, owing to increases in overweight and obesity, decreasing physical activity and the changing demographic structure of the population. People can develop T2DM without symptoms and up to 20% may be undiagnosed. They may have diabetic complications, such as retinopathy, by the time they are diagnosed, or may suffer a heart attack, without warning. Undiagnosed diabetes can be detected by raised blood glucose levels.

AIM

The aim of this review was to provide an update for the UK National Screening Committee (NSC) on screening for T2DM.

METHODS

As this review was undertaken to update a previous Health Technology Assessment review published in 2007, and a more recent Scottish Public Health Network review, searches for evidence were restricted from 2009 to end of January 2012, with selected later studies added. The databases searched were MEDLINE, EMBASE, MEDLINE-in-Process & Other Non-Indexed Citations, Science Citation Index and Conference Proceedings Citation Index. The case for screening was considered against the criteria used by the NSC to assess proposed population screening programmes.

RESULTS

Population screening for T2DM does not meet all of the NSC criteria. Criterion 12, on optimisation of existing management, has not been met. A report by the National Audit Office (NAO) gives details of shortcomings. Criterion 13 requires evidence from high-quality randomised controlled trials that screening is beneficial. This has not been met. The Ely trial of screening showed no benefit. The ADDITION trial was not a trial of screening, but showed no benefit in cardiovascular outcomes from intensive management in people with screen-detected T2DM. Criterion 18 on staffing and facilities does not appear to have been met, according to the NAO report. Criterion 19 requires that all other options, including prevention, should have been considered. A large proportion of cases of T2DM could be prevented if people avoided becoming overweight or obese. The first stage of selection would use risk factors, using data held on general practitioner computer systems, using the QDiabetes Risk Score, or by sending out questionnaires, using the Finnish Diabetes Risk Score (FINDRISC). Those at high risk would have a measure of blood glucose. There is no perfect screening test. Glycated haemoglobin (HbA1c) testing has advantages in not requiring a fasting sample, and because it is a predictor of vascular disease across a wider range than just the diabetic one. However, it lacks sensitivity and would miss some people with diabetes. Absolute values of HbA1c may be more useful as part of overall risk assessment than a dichotomous 'diabetes or not diabetes' diagnosis. The oral glucose tolerance test is more sensitive, but inconvenient, more costly, has imperfect reproducibility and is less popular, meaning that uptake would be lower.

CONCLUSIONS

When considered against the NSC criteria, the case for screening is less strong than it was in the 2007 review. The main reason is the absence of cardiovascular benefit in the two trials published since the previous review. There is a case for selective screening as part of overall vascular risk assessment. Population screening for T2DM does not meet all of the NSC criteria.

FUNDING

The National Institute for Health Research Health Technology Assessment programme.

Glucagon-like peptide analogues for type 2 diabetes mellitus: systematic review and meta-analysis

BACKGROUND

Glucagon-like peptide (GLP-1) analogues are a new class of drugs used in the treatment of type 2 diabetes. They are given by injection, and regulate glucose levels by stimulating glucose-dependent insulin secretion and biosynthesis, suppressing glucagon secretion, and delaying gastric emptying and promoting satiety. This systematic review aims to provide evidence on the clinical effectiveness of the GLP-1 agonists in patients not achieving satisfactory glycaemic control with one or more oral glucose lowering drugs.

METHODS

MEDLINE, EMBASE, the Cochrane Library and Web of Science were searched to find the relevant papers. We identified 28 randomised controlled trials comparing GLP-1 analogues with placebo, other glucose-lowering agents, or another GLP-1 analogue, in patients with type 2 diabetes with inadequate control on a single oral agent, or on dual therapy. Primary outcomes included HbA1c, weight change and adverse events.

RESULTS

Studies were mostly of short duration, usually 26 weeks. All GLP-1 agonists reduced HbA1c by about 1% compared to placebo. Exenatide twice daily and insulin gave similar reductions in HbA1c, but exenatide 2 mg once weekly and liraglutide 1.8 mg daily reduced it by 0.20% and 0.30% respectively more than glargine. Liraglutide 1.2 mg daily reduced HbA1c by 0.34% more than sitagliptin 100 mg daily. Exenatide and liraglutide gave similar improvements in HbA1c to sulphonylureas. Exenatide 2 mg weekly and liraglutide 1.8 mg daily reduced HbA1c by more than exenatide 10 μg twice daily and sitagliptin 100 mg daily. Exenatide 2 mg weekly reduced HbA1c by 0.3% more than pioglitazone 45 mg daily.Exenatide and liraglutide resulted in greater weight loss (from 2.3 to 5.5 kg) than active comparators. This was not due simply to nausea. Hypoglycaemia was uncommon, except when combined with a sulphonylurea. The commonest adverse events with all GLP-1 agonists were initial nausea and vomiting. The GLP-1 agonists have some effect on beta-cell function, but this is not sustained after the drug is stopped.

CONCLUSIONS

GLP-1 agonists are effective in improving glycaemic control and promoting weight loss.

Self monitoring of blood glucose - a survey of diabetes UK members with type 2 diabetes who use SMBG

BACKGROUND

Aim - to survey members of Diabetes UK who had Type 2 diabetes and who used self monitoring of blood glucose (SMBG), to elicit their views on its usefulness in the management of their diabetes, and how they used the results. A questionnaire was developed for the Diabetes UK website. The questionnaire was posted on the Diabetes UK website until over 500 people had responded. Questions asked users to specify the benefits gained from SMBG, and how these benefits were achieved. We carried out both quantitative analysis and a thematic analysis for the open ended free-text questions.

FINDINGS

554 participants completed the survey, of whom 289 (52.2%) were male. 20% of respondents were recently diagnosed (< 6 months). Frequency of SMBG varied, with 43% of participants testing between once and four times a day and 22% testing less than once a month or for occasional periods.80% of respondents reported high satisfaction with SMBG, and reported feeling more 'in control' of their diabetes management using it. The most frequently reported use of SMBG was to make adjustments to food intake or confirm a hyperglycaemic episode.Women were significantly more likely to report feelings of guilt or self-chastisement associated with out of range readings (p = < .001).

CONCLUSION

SMBG was clearly of benefit to this group of confirmed users, who used the results to adjust diet, physical activity or medications. However many individuals (particularly women) reported feelings of anxiety and depression associated with its use.

Glycaemic control and body mass index in late-adolescents and young adults with Type 1 diabetes mellitus: a population-based study

AIMS

Studies of children with diabetes up to the age of 15 years report deteriorating glycaemic control in the early teenage years. The aim was to investigate glycaemia and body mass index in older teenagers and young adults.

METHOD

A Scottish, regional, population-based, cross-sectional study of 255 young people (117 female, 138 male) with Type 1 diabetes, aged 15-25 years (mean +/-sd 19.8 +/- 2.8 years, diabetes duration: 8.8 +/- 5.4 years) registered on a diabetes database. Glycaemic control, body mass index (BMI) and insulin regimens were assessed in three age groups [group 1 (n = 96) 15-18 years; group 2 (n = 74) 18.1-22 years; and group 3 (n = 85) 22.1-25 years].

RESULTS

Subjects in the oldest age group had a significantly lower mean HbA(1c) than those in the youngest age group (8.8 +/- 1.7 vs. 9.9 +/- 1.9%; P < 0.001). Mean BMI was higher in group 3 (25.2 +/- 3.4 kg/m(2)) compared with group 1 (23.9 +/- 3.1 kg/m(2); P < 0.001). HbA(1c )levels were higher in the younger subjects and women. Lower HbA(1c) levels were associated with a higher BMI (r = -0.324, P < 0.001) in men only. Overall, 74% took three or more injections a day, of whom 60% were on basal/bolus therapy. The proportion on basal/bolus insulin therapy increased with age and duration of diabetes.

CONCLUSION

Compared with adolescents, young adults with Type 1 diabetes have better glycaemic control and higher BMI. This was associated with lower insulin requirements.

Making literature searches easier: a rapid and sensitive search filter for retrieving randomized controlled trials from PubMed

AIMS

To develop and test the sensitivity and precision of a rapid and simple search filter (RSSF), suitable for busy clinicians wanting to find randomised controlled trials (RCTs) in PubMed. Ideally it should retrieve all the RCTs, but as few irrelevant studies as possible, and be easy to use.

METHODS

The RSSF consisted of the search term 'Randomized Controlled Trial' limited to the Publication Type field. Journals that published the highest numbers of diabetes RCTs between 2000 and 2005 were identified, and then handsearched in order define a set of known RCTs. The sensitivity of the RSSF was tested by measuring the proportion of the known RCTs retrieved, and the precision by checking the proportion of the retrieved studies which were RCTs. The RSSF was compared to a highly sensitive search strategy (HSSS) developed for PubMed. Embase was checked for trials not in PubMed.

RESULTS

Sixteen journals were found to contain half of all published RCTs in diabetes. 820 diabetes RCTs were identified by handsearching. Measured against these, the RSSF gave a sensitivity of 96.0% (95% CI, 94.8% to 97.1%), and a precision of 93.6% (95% CI 91.7% to 95.0%). Compared to the HSSS, the RSSF reduced the filtering required by 87%. An Embase search for diabetes RCTs found 36 (2.1%) not in PubMed.

CONCLUSIONS

A rapid simple search filter for PubMed can find almost all diabetes RCTs, while excluding most studies not required, thereby greatly reducing the time cost of searching and filtering results, and of searching other databases.

United Kingdom cervical cancer screening and the costs of time and travel

OBJECTIVES

The aim of this study was to estimate the time and travel costs generated by women when attending for Papanicolaou (Pap) smear tests or colposcopy appointments in the United Kingdom, both absolutely and relative to the health service cost of the national cervical cancer screening programs.

METHODS

Data were obtained from questionnaires completed by two samples of women participating in a three-center trial of management of low-grade abnormalities detected by screening (n = 1,106 for Pap smears and n = 1,203 for colposcopy appointments). Women were 20 to 59 years of age and resident in Grampian or Tayside, Scotland, or Nottingham, England. Questionnaire data were supplemented with sociodemographic information previously collected at the time of recruitment to the trial.

RESULTS

The mean total time and travel costs per attendance at a smear test and at a colposcopy appointment were estimated to be 9.2 pounds and 27.4 pounds, respectively, averaged across the three trial areas (valued at 2002 prices). Statistically significant intercenter disparities in time and travel costs were identified, particularly with respect to colposcopy appointments. For these, time and travel costs in Nottingham were substantially less than those in Grampian and Tayside (22.9 pounds, 30.2 pounds, and 32.1 pounds, respectively). Time and travel costs amount to 26 and 33 percent, approximately, over and above the direct health service costs of the English and Scottish screening programs, respectively.

CONCLUSIONS

The time and travel costs associated with participation in the UK cervical cancer screening programs are substantial and are not spatially uniform across the country.

Sources of evidence for systematic reviews of interventions in diabetes

AIMS

To analyse the effect on systematic reviews in diabetes interventions of including only trials that are indexed in medline, and to assess the impact of adding trials from other databases and the grey literature.

METHODS

All systematic reviews of diabetes interventions which included a meta-analysis of randomized controlled trials, and were published since 1996, were selected. The impact on the meta-analysis of including only those trials indexed in medline, and the effect of then adding trials from other sources, was assessed. Where possible this was measured quantitatively, by redoing the meta-analysis, otherwise a qualitative estimate was made.

RESULTS

Forty-four systematic reviews met our inclusion criteria. There were 120 articles reporting trial data which were not indexed in medline. These came from 52% of the reviews. In 34% of the reviews, basing a meta-analysis on a search of only medline would miss trials that could affect the result. Sources of non-medline data which had the biggest effect on the meta-analyses were journal articles from central and embase (mainly in Diabetes, Nutrition and Metabolism) and unpublished data (mainly from industry). The exceptions were journal articles on herbal medicine, mostly indexed in Chinese language databases.

CONCLUSIONS

A search of only the medline database is insufficient for systematic reviews of diabetes, because in about 34% of reviews the missed trials could affect the results of the meta-analysis. It is recommended that central (on the Cochrane Library) also be searched. Scanning meeting abstracts, and seeking unpublished data are also recommended if the intervention has only recently been introduced.

Cancer incidence and mortality in patients with insulin-treated diabetes: a UK cohort study

Raised risks of several cancers have been found in patients with type II diabetes, but there are few data on cancer risk in type I diabetes. We conducted a cohort study of 28 900 UK patients with insulin-treated diabetes followed for 520 517 person-years, and compared their cancer incidence and mortality with national expectations. To analyse by diabetes type, we examined risks separately in 23 834 patients diagnosed with diabetes under the age of 30 years, who will almost all have had type I diabetes, and 5066 patients diagnosed at ages 30–49 years, who probably mainly had type II. Relative risks of cancer overall were close to unity, but ovarian cancer risk was highly significantly raised in patients with diabetes diagnosed under age 30 years (standardised incidence ratio (SIR)=2.14; 95% confidence interval (CI) 1.22–3.48; standardised mortality ratio (SMR)=2.90; 95% CI 1.45–5.19), with greatest risks for those with diabetes diagnosed at ages 10–19 years. Risks of cancer at other major sites were not substantially raised for type I patients. The excesses of obesity- and alcohol-related cancers in type II diabetes may be due to confounding rather than diabetes per se.

Clinical- and cost-effectiveness of pegylated interferon alfa in the treatment of chronic hepatitis C: a systematic review and economic evaluation

OBJECTIVES

To assess the clinical-effectiveness and cost-effectiveness of pegylated interferon alfa (2a and 2b) combined with ribavirin in previously untreated patients with moderate to severe chronic hepatitis C, compared with the current standard treatment, which is nonpegylated interferon alfa combined with ribavirin.

METHODS

Systematic review and economic evaluation. A sensitive search strategy was applied to several electronic bibliographic databases. Relevant studies were critically appraised and meta-analyzed. A hypothetical cohort of 1,000 patients entered a Markov model and were followed up for a more than 30-year period to predict natural history, duration spent in each health state, and treatment costs.

RESULTS

Two fully published Phase III randomized controlled trials were included. Methodological quality was generally good. Dual therapy with pegylated interferon was significantly more effective than nonpegylated dual therapy with a pooled sustained virological response rate (SVR) of 55 percent (95 percent confidence interval [CI], 52-58 percent) compared with 46 percent (95 percent CI, 43-49 percent). The pooled relative risk of remaining infected was 0.83 (95 percent CI, 0.76-0.91 percent). Genotype was the strongest predictor of outcome, with SVRs in patients with the more responsive genotypes 2 and 3 reaching up to 80 percent. The incremental cost per quality-adjusted life year (QALY) for pegylated dual therapy compared with nonpegylated dual therapy was 12,123 pounds sterling. The cost per QALY remained under 30,000 pounds sterling for most patient subgroups and in sensitivity analyses.

CONCLUSIONS

Pegylated interferon is clinically effective, represents good value for the money, and is a significant advance in the treatment of this insidious disease.

Mortality of South Asian patients with insulin-treated diabetes mellitus in the United Kingdom: a cohort study

AIMS

To investigate mortality in South Asian patients with insulin-treated diabetes and compare it with mortality in non South Asian patients and in the general population.

METHODS

A prospective cohort study was conducted of 828 South Asian and 27 962 non South Asian patients in the UK with insulin-treated diabetes diagnosed at ages under 50 years. The patients were followed for up to 28 years. Ethnicity was determined by analysis of names. Standardized mortality ratios (SMRs) were calculated, comparing mortality in the cohort with expectations from the mortality experience of the general population.

RESULTS

SMRs were significantly raised in both groups of patients, particularly the South Asians, and especially in women and subjects with diabetes onset at a young age. The SMRs for South Asian patients diagnosed under age 30 years were 3.9 (95% CI 2.0-6.9) in men and 10.1 (5.6-16.6) in women, and in the corresponding non South Asians were 2.7 (2.6-2.9) and 4.0 (3.6-4.3), respectively. The SMR in women was highly significantly greater in South Asians than non South Asians. The mortality in the young-onset patients was due to several causes, while that in the patients diagnosed at ages 30-49 was largely due to cardiovascular disease, which accounted for 70% of deaths in South Asian males and 73% in females.

CONCLUSIONS

South Asian patients with insulin-treated diabetes suffer an exceptionally high mortality. Clarification of the full reasons for this mortality are needed, as are measures to reduce levels of known cardiovascular disease risk factors in these patients.

Mortality from heart disease in a cohort of 23,000 patients with insulin-treated diabetes

AIMS/HYPOTHESIS

Although ischaemic heart disease is the predominant cause of mortality in older people with diabetes, age-specific mortality rates have not been published for patients with Type 1 diabetes. The Diabetes UK cohort, essentially one of patients with Type 1 diabetes, now has sufficient follow-up to report all heart disease, and specifically ischaemic heart disease, mortality rates by age.

METHODS

A cohort of 23,751 patients with insulin-treated diabetes, diagnosed under the age of 30 years and from throughout the United Kingdom, was identified during the period 1972 to 1993 and followed for mortality until December 2000. Age- and sex-specific heart disease mortality rates and standardised mortality ratios were calculated.

RESULTS

There were 1437 deaths during the follow-up, 536 from cardiovascular disease, and of those, 369 from ischaemic heart disease. At all ages the ischaemic heart disease mortality rates in the cohort were higher than in the general population. Mortality rates within the cohort were similar for men and women under the age of 40. The standardised mortality ratios were higher in women than men at all ages, and in women were 44.8 (95%CI 20.5-85.0) at ages 20-29 and 41.6 (26.7-61.9) at ages 30-39.

CONCLUSIONS/INTERPRETATION

The risk of mortality from ischaemic heart disease is exceptionally high in young adult women with Type 1 diabetes, with rates similar to those in men with Type 1 diabetes under the age of 40. These observations emphasise the need to identify and treat coronary risk factors in these young patients.

Mortality from cerebrovascular disease in a cohort of 23 000 patients with insulin-treated diabetes

BACKGROUND AND PURPOSE

Disease of the cardiovascular system is the main cause of long-term complications and mortality in patients with type I (insulin-dependent) and type II (non-insulin-dependent) diabetes. Cerebrovascular mortality rates have been shown to be raised in patients with type II diabetes but have not previously been reported by age and sex in patients with type I diabetes.

METHODS

A cohort of 23 751 patients with insulin-treated diabetes, diagnosed under the age of 30 years from throughout the United Kingdom, was identified during 1972 to 1993 and followed up for mortality until the end of December 2000. Age- and sex-specific mortality rates and standardized mortality ratios (SMRs) were calculated.

RESULTS

There were 1437 deaths during the follow-up, 80 due to cerebrovascular disease. Overall, the cerebrovascular mortality rates in the cohort were higher than the corresponding rates in the general population, and the SMRs were 3.1 (95% CI, 2.2 to 4.3) for men and 4.4 (95% CI, 3.1 to 6.0) for women. When stratified by age, the SMRs were highest in the 20- to 39-year age group. After subdivision of cause of death into hemorrhagic and nonhemorrhagic origins, there remained a significant increase in mortality from stroke of nonhemorrhagic origin.

CONCLUSIONS

Analyses of mortality from this cohort, essentially one of patients with type I diabetes, has shown for the first time that cerebrovascular mortality is raised at all ages in these patients. Type I diabetes is at least as great a risk factor for cerebrovascular mortality as type II diabetes.

Protein restriction for diabetic renal disease

OBJECTIVES

To determine whether protein restriction slows or prevents progression of diabetic nephropathy towards renal failure.

SEARCH STRATEGY

Computerised databases MEDLINE (1976-1996) and EMBASE (1974-1996) were searched using keywords diabetes mellitus, diabetic nephropathy, dietary proteins, diet, protein restricted and uremia. Recent issues of selected journals (Diabetic Medicine, Diabetologia, Diabetes Care, Kidney International, Nephrology Dialysis and Transplantation) were handsearched for papers not yet in the computerised databases. Reference lists of papers were also checked.

SELECTION CRITERIA

This review was not limited to randomised controlled trials. All trials involving people with insulin-dependent diabetes following a lower protein diet for at least 4 months were considered since the straight line nature of progression as reflected by GFR means that patients can act as their own controls in a before and after comparison.

DATA COLLECTION AND ANALYSIS

Data were extracted for length of follow up, level of protein restriction, renal function and dietary compliance. No studies of the impact of protein restriction on outcomes such as the need for dialysis or transplantation were found. The trials reported only the effect on short-term indicators such as creatinine clearance.

MAIN RESULTS

Overall a protein restricted diet (0.3-0. 8g/kg) does appear to slow the progression of diabetic nephropathy towards renal failure.

REVIEWER'S CONCLUSIONS

The results show that reducing protein intake appears to slow progression to renal failure, but some questions remain unanswered. The first is what level of protein restriction we should be used? The trials aimed for a daily intake of between 0.3 to 0.8g/kg of protein. The second concerns compliance in routine care - what level would be acceptable to patients? The third concerns long term outcomes -the present trials use proxy indicators such as creatinine clearance rather than outcomes such as time to dialysis or prevention of ESRF. All trials were carried out in subjects with insulin-dependent diabetes. It remains to be seen if a lower protein intake would slow the progression of nephropathy affecting the non-insulin dependent diabetic population.

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.

Rising incidence of type 1 diabetes in Scottish children, 1984-93. The Scottish Study Group for the Care of Young Diabetics

OBJECTIVES

To calculate the incidence of type 1 diabetes in Scottish children aged less than 15 years between 1984 and 1993; to examine changes in incidence; and to calculate the prevalence of diabetes at the end of this period.

DESIGN

Three data sources were used to construct the Scottish Study Group for the Care of Young Diabetics register: active reporting of all new cases; reports from the Scottish Morbidity Register 1; and local registers.

SUBJECTS

All children resident in Scotland diagnosed with primary insulin dependent diabetes mellitus when less than 15 years of age between 1984 and 1993.

MAIN OUTCOME MEASURES

Annual incidence and prevalence rate for Scotland; time trend in incidence over the 10 years; differences in incidence between the three different age groups; and completeness of the register.

RESULTS

The average annual incidence for Scotland was 23.9/100,000 children. The prevalence rate was 1.5/1000 in 1993. A total of 2326 cases was identified from the three sources. Capture-recapture analysis suggests a case ascertainment of 98.6%. The annual incidence rates increased at a rate of 2% each year (rate ratio = 1.02, 95% confidence interval (CI) 1.01 to 1.03). The incidence was higher in boys than girls (rate ratio = 1.08, 95% CI 1.00 to 1.18), and the incidence rates increased with age: 15.3/100,000/year for age 0-4 years, 24.4/ 100,000/year for age 5-9 years, and 31.9/ 100,000/year for age 10-14 years.

CONCLUSIONS

The incidence of type 1 diabetes in Scotland is increasing and the prevalence is relatively high. These findings have important implications for health service resource allocation. The Scottish Study Group for the Care of Young Diabetics' register provides a base for monitoring and research.

Hypothermia in the north east of Scotland

The aim of the study was to establish the incidence of hypothermia in the Grampian region, and to examine the accuracy of routine reporting of hypothermia on hospital discharge records. From 1990-1994, 167 patients were admitted with an SMRI diagnosis of hypothermia. An admission temperature of under 35 degrees C was recorded in 47 (28%); rectal in 37 (confirmed hypothermia) and not specified on non-rectal in 10 (possible hypothermia). Most admissions were during the winter months in only 18 cases of the 47 patients with confirmed or possible hypothermia was a secondary cause not apparent. Isolated hypothermia is rare in Grampian. In most cases other disease is the underlying cause.

A case-control investigation of perinatal risk factors for childhood IDDM in Northern Ireland and Scotland

OBJECTIVE

To identify perinatal risk factors for childhood insulin-dependent diabetes mellitus (IDDM) and determine if they differ between early-onset and late-onset disease.

RESEARCH DESIGN AND METHODS

We selected 258 diabetic children in Northern Ireland and 271 diabetic children in Scotland from population-based registers. For each diabetic child, five matched control subjects were drawn from the same population. All perinatal data were recorded routinely at birth. Odds ratios (ORs) were estimated for parental age, social class, breast-feeding, deprivation measures, and other perinatal variables.

RESULTS

Scottish data indicated an increased risk among children born to older mothers (OR = 2.43, 95% confidence interval [CI] 1.49-3.97 for mothers > or = 35 years of age relative to those < 25 years of age). Northern Ireland data showed no such effect. Only Northern Ireland data showed an excess risk in children of professional or managerial families (OR = 1.51, 95% CI 1.11-2.04). A small but nonsignificant reduction in risk among breast-fed children was observed only after adjustment for social class (OR = 0.76, 95% CI 0.54-1.07). Deprivation measures were associated with reductions in risk. Children delivered by cesarean section were at increased risk in both Northern Ireland (OR = 1.66, 95% CI 1.10-2.50) and Scottish (OR = 1.70, 95% CI 1.12-2.59) data. In Northern Ireland data only, children of first pregnancies were at increased risk (OR = 1.41, 95% CI 1.03-1.93). Both data sets indicated that a first pregnancy was a more important risk factor for early-onset disease than for late-onset disease.

CONCLUSIONS

Many reported risk factors are weak and show inconsistencies between studies. They may be secondary to more direct, as-yet-undiscovered risk factors. Although irrelevant in the majority of cases, the increased risk associated with delivery by cesarean section deserves further study.

Trends in morbidity and mortality from peptic ulcer disease: Tayside versus Scotland

Recent studies have shown that the prophylactic use of H2-receptor antagonists reduces both ulcer recurrence and the risk of ulcer complications. Despite these results, epidemiological studies have failed to show any evidence of an effect of gastric anti-secretory drugs on complicated ulcer disease in the community. Since 1979, it has been the policy of the gastroenterology department at Ninewells Hospital in Tayside to recommend long-term, continuous therapy with H2-receptor antagonists for patients with peptic ulcer; in contrast, prophylactic therapy is less commonly used in the rest of Scotland. The difference in the management of peptic ulcer between Tayside and Scotland presented an opportunity to study the population effects of the widespread use of continuous H2-receptor antagonists on the morbidity and mortality from ulcer disease. This study compared the trends in hospital admissions, gastric surgery, haemorrhage, perforation and mortality from ulcer disease using data supplied by the Information and Statistics Division of the Common Services Agency, Scottish Health Service, Edinburgh. During the 1980s, hospital admissions for peptic ulcer declined significantly in Tayside, whereas in Scotland there was no obvious downward trend. Gastric surgery for ulcer disease declined throughout Scotland although the fall was significantly steeper in Tayside than in the rest of Scotland. For the population in general, the rate of perforation decreased faster in Tayside than in the rest of Scotland, although the difference was not significant. The rate of admissions for ulcer haemorrhage declined substantially in Tayside whereas there was little change in Scotland as a whole. The decrease in mortality from ulcer disease in all groups except younger females was more marked in Tayside than in Scotland, although the differences were not significant. The magnitude of the differences between Tayside and Scotland, and in particular the consistency of these results across a broad range of indicators of ulcer disease, suggests that the policy of prescribing long-term, continuous therapy with H2-receptor antagonists has reduced both uncomplicated and complicated peptic ulcer in the community in Tayside.

Audit of the quality of hospital discharge data

An audit of the quality of computerised hospital discharge data, in General Medicine and Paediatrics in Dundee, showed that the national data set was often inaccurate. Structured discharge summaries checked by senior medical staff are recommended.

An audit of the quality of cancer registration data

The accuracy of cancer registration data in the East of Scotland (Tayside) Cancer Registry was audited by comparing 200 consecutive registrations (about 10% of the annual total) with the 'gold standard' of the Histopathology records. ICD codes were independently generated by a pathologist by examining final pathology reports and then compared to those codes given by the local cancer registrar. Discrepancies were graded by the pathologist and the epidemiologist according to severity. Major errors of coding were few. Minor and moderate differences in coding occurred because of the nature and structure of the coding system and the manner in which data are retrieved. The level of detail required by the Cancer Registry needs to be evaluated.

Microangiopathy as a prognostic indicator in diabetic patients suffering from acute myocardial infarction

Diabetic patients have an increased mortality following myocardial infarction (MI) due to left ventricular failure rather than larger infarcts or dysrhythmias. As this may be due to diabetic microangiopathy affecting the myocardium, we have examined the case records of diabetic clinic patients admitted to the Coronary Care Unit (CCU) with proven MI and compared the hospital outcome of those with and without retinopathy or nephropathy, i.e. markers for generalised microangiopathy. Sixty four consecutive records were traced, for the period when diabetic treatment policy was standardised in CCU, 24 patients had retinopathy (7 proteinuria). When compared to non-retinopathy patients they had similar ages 67 +/- 12 yr [+/- SD] v 63 +/- 9yr) but were of longer duration of diabetes p less than 0.05). There were no differences between the groups in size or site of infarct, previous infarct or hypertension history, blood glucose on admission or diabetic treatment before or after admission. Death occurred in 29% of retinopathy patients compared to 3% of non-retinopathy patients (p less than 0.01). Cardiac failure complicated 75% of retinopathy patients and 25% of non-retinopathy patients (p less than 0.001). Dysrhythmia occurred in 50% and 33% of patients respectively (P = NS). Nine patients had clinical peripheral vascular disease and five of these died. This study, of a selected group of diabetic clinic attenders admitted to CCU with acute MI, demonstrates that microangiopathy and peripheral vascular disease are important prognostic factors in determining hospital outcome as these patients are at increased risk of cardiac failure and death.

Urban/rural and deprivational differences in incidence and clustering of childhood diabetes in Scotland

Scottish hospital discharges were monitored during the period 1977-1983 for new cases of diabetes in children aged 18 years or under. An estimated ascertainment rate of 94% was obtained by validation against an independent register of cases. The postcode sector at the time of admission was available for 2125 (97%) of the 2183 cases, and was used as the basis for a small-area analysis of urban/rural and socioeconomic differences in incidence and to test for clustering. Incidence rates standardized for age and sex showed important differences between the 16 Scottish postcode areas. At the sector level, the standardized rate was 20% lower in urban sectors compared to rural sectors, but this could be explained by area to area differences and by socioeconomic effects within areas. In contrast, significant socioeconomic differences in incidence were evident within areas which could not be explained by urban/rural effects, the children in deprived sectors having 80% of the risk of those in other sectors. Rates were particularly low among children in deprived urban sectors. Nevertheless, significant variations in incidence remained between the 16 areas which could not be explained by either urban/rural or socioeconomic differences, indicating the existence of other important factors. Tests for clustering of cases both within postcodes sectors and across adjacent postcode sectors were also performed. Although clusters could be identified, they were no more common than would be expected by chance. Tests for space-time clustering were also negative.

The Dundee prevalence study of insulin-treated diabetes; intervals between diagnosis and start of insulin therapy

A population-based survey of the prevalence of insulin-treated diabetes mellitus in the Dundee area showed a crude prevalence of 0.34%, but analysis by interval between diagnosis of diabetes and start of insulin shows that around a third of patients started insulin therapy more than 1 month after diagnosis. This suggests that the prevalence of insulin-dependent diabetes is around 0.2% of the population, with the other patients being those with non-insulin-dependent diabetes who need insulin for metabolic control, though there is an intermediate zone where classification is difficult. There is a male excess. The proportion of true insulin-dependent diabetes falls with age of onset, but around 50% of such patients have an onset over the age of 30 years.

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

In a prospective study of mortality in a large group of Scottish diabetic patients, ischaemic heart disease was responsible for 51% of deaths, with the diabetic relative risks of death being 3.8, 2.7 and 2.2 for the age groups 45-64, 65-74, and 75 years and over, respectively. The diabetic relative risks for mortality from all causes were 5.5, 2.3, 1.7, 1.3 for age ranges 15-44, 45-64, 65-74, and 75 and over, respectively. The all cancer mortality rate is not reduced in diabetic individuals.

Proteinuria prevalence in insulin-treated patients: prediction of need for end-stage renal failure treatment

In the Dundee Diabetic clinic area (population circa 250,000), a population-based survey of the prevalence of proteinuria in diabetic patients treated with insulin showed that 9.4% of such patients had persistent proteinuria. The percentage of males with proteinuria was 11.4%, against 7.2% of females. An additional 5.2% of patients had proteinuria observed once, but did not meet the criteria for persistent proteinuria. No result was available in 10% of patients for a variety of reasons. Not every patient with diabetes and persistent proteinuria will progress to end-stage renal failure, but consideration of the group as a whole allows predictions based on published reports, to be made of the likely future incidence of renal failure, and hence future need for renal replacement services. We estimate that over the next decade two patients per 125,000 total population will develop renal failure each year. If survival is unchanged, there could be two or three times that number on treatment at any time.

Insulin-dependent diabetes in a Scottish region: incidence and urban/rural differences

The incidence of insulin-dependent diabetes mellitus in the 0-18 year age group was studied in Tayside Region for the years 1980 to 1983. The mean annual rate of 21.7 per 100,000 is high in international terms and suggests that the rise in incidence observed in Scotland in the 1970s has continued. Urban and rural incidences were compared using postcodes. Rural rates were significantly (0.02 greater than p greater than 0.01) higher, due mainly to the difference in rates for the 0-9 age groups.