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.

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.

Latest trends in cancer incidence among UK South Asians in Leicester.

Using cancer registry data, we show that although South Asians have lower rates of cancer than the rest of the population, this is changing with age and time. Younger South Asians, particularly children, are at increased risk. While generally cancer rates have fallen over the last decade, they are increasing among South Asians.

Breast cancer incidence and mortality trends in 16 European countries.

Trends in the incidence of and mortality from breast cancer result from a variety of influences including screening programmes, such as those introduced in several European countries in the late 1980s. Incidence and mortality rates for 16 European countries are analysed. Incidence increased in all countries. The estimated annual percent change (EAPC) varied from 0.8 to 2.8% in prescreening years in 6 'screened' countries and from 1.2 to 3.0% in 10 'non-screened' countries. Screening related temporary increases were visible. Earlier mortality trends were maintained in the most recent decade in Estonia (EAPC +1.8%) and Sweden (-1.2%). In other countries, previously increasing trends changed. Trends flattened in Finland, Denmark, France, Italy and Norway (EAPC 0.0 to -0.3%), while they declined in England and Wales (-3.1%), Scotland (-2.0%), and The Netherlands (-1.0%), all of which have national screening programmes, and in Slovakia (-1.1%), Spain (-0.7%), and Switzerland (-1.1%). In some countries with screening programmes, declines in mortality started before screening was introduced, and declines also occurred in non-screened age groups and in some countries without national screening programmes. This suggests that the major determinants of the observed trends vary among the countries and may include earlier detection through screening in countries where this has been introduced, but also improvements in therapy, in countries with or without screening.

What is the prevalence of visual impairment in the general and diabetic populations: are there ethnic and gender differences?

AIMS: To estimate the prevalence of blindness and partial sight in the general and diabetic populations and to measure the impact of ethnicity and gender on these rates. METHODS: Data on visual impairment in the population to be studied was obtained from the Royal Leicestershire Rutland and Wycliffe Society for the Blind (RLRWSB). Using the validated technique of capture-mark-recapture (CMR), a census day was set and data from four sources collected: hospital admissions data, GP returns, wards, and mass media. Computer cross-linkage to Leicestershire Health Authority data ensured patients were alive and resident in Leicestershire at the census date. Estimates of diabetes, ethnicity and gender prevalence were calculated using the 1991 census. RESULTS: CMR calculations revealed that there was under ascertainment of visual impairment in the RLRWSB data. The CMR calculations with direct age standardization estimate the prevalence of blindness and partial sight in the general and diabetic populations to be 51.8/10 000 (CI 50.6-53.0) and 148.8/10 000 (CI 122.1-175.5), respectively. In the diabetic population there was a higher proportion of visually impaired females than males (P < 0.05), with no overall ethnic differences; however, rates were lower than expected in female Indo-Asians. In the general population there was a higher proportion of visually impaired Indo-Asian people (P < 0.01). CONCLUSIONS: Our study has shown the prevalence of visual impairment in both the general and diabetic populations and has demonstrated both ethnic and gender differences. CMR allows the calculation of prevalence of blindness and partial sight from existing data. When comparing the prevalence of visual impairment, whether from diabetes or other causes, it is important to know the gender and ethnicity of the 'at risk' population, as well as the rates in the background population.

Comparative incidence of Type I diabetes in children aged under 15 years from South Asian and White or Other ethnic backgrounds in Leicestershire, UK, 1989 to 1998.

AIMS/HYPOTHESIS: Estimates of incidence of Type I (insulin-dependent) diabetes mellitus in childhood populations vary around the world. This study aimed to estimate and compare the incidence of Type I diabetes in Leicestershire of children of South Asian and White or Other ethnic backgrounds. METHODS: All new cases of childhood-onset Type I diabetes diagnosed before 15 years of age in Leicestershire during the period 1989-98 were studied. Population data for Leicestershire from the 1991 census was used. Ethnicity was assigned to all children in the study according to their surnames. Incidence rates (95%-Confidence limits) for the South Asian and white or other ethnic group were estimated and compared. RESULTS: Over the 10-year period, 46 South Asian children and 263 children who were white or from another ethnic group fulfilled the criteria for inclusion in the study. Crude incidence rates per 100,000 person-years were 19.2 (12.0, 29.1) girls and 20.3 (13.0, 30.3) boys for South Asians and 17.7 (14.8, 21.1) girls and 17.7 (14.8, 20.9) boys for whites/others. Age and sex-specific rates were higher for South Asians over 5 years of age but differences were not statistically significant. CONCLUSION/INTERPRETATION: Type I diabetes incidence rates for South Asian children in Leicestershire were very similar to those for children who were in the white/other ethnic group, in contrast to very low rates reported from Asia. The convergence of rates for South Asians with other ethnic groups in Leicestershire suggests that environmental factors are more important than genetic predisposition in causing Type I diabetes in people of South Asian ethnic background.

Characteristics of non-responders to diabetes service use questionnaires.

Postal surveys of service use are likely to overestimate health service use and may also underestimate health needs in the population. A historical cohort study, using postal questionnaires and medical records, showed that non-respondents are registered at addresses in more-deprived wards, they are less likely to have attended a hospital diabetes clinic (38% vs 45%) and much less likely to have had a diabetes review in general practice (11% vs 26%). An analysis based on questionnaire respondents would only therefore both underestimate the level of material deprivation and overestimate the proportion receiving routine reviews in general practice in a population with a chronic condition.

Breast and cervical cancer survival: making sense of "league tables".

During 1998, the Department of Health proposed to use survival rates of cervical and breast cancer in the 1989/90 incidence cohort as indicators of care. Valid interpretation was of concern within Trent and the Trent Cancer Registry responded by performing additional analyses. Trent Cancer Registry registrations for 1989/90 were re-analysed and the stability of districts' ranks for that cohort was investigated using random simulation techniques. Stability of ranks across more recent cohorts was investigated and attempts made to use all available information. The Department of Health's analyses were confirmed by our re-analysis of the 1989/90 cohort: Rotherham residents appeared to have the "worst" survival for cervical cancer, and Sheffield residents for breast cancer, although not statistically significantly so. Random simulations indicated that ranks based on a single cohort are not stable: for example Sheffield (ranked tenth for 1-y breast cancer survival) was ranked third or better in 6% of randomisations. Ranks were also unstable across cohorts: for example Rotherham 1-y cervical cancer survival was ranked tenth for 1989/90, fifth for 1991/92 and tenth for 1993/94. Analysis of 3-y running averages provided better information than the league table approach. Most districts improved over time, to different degrees, and similar sized gaps remained between the "best" and the "worst" districts. This analysis illustrates the need to be circumspect when interpreting "league tables" based on a single year or cohort analysis. League tables are based on ranks: clearly a large difference in rank may reflect only trivial (ie medically unimportant) differences in actual outcome. Lack of a statistically significant difference in survival between two districts does not mean their survival is equivalent. Even for a common cancer, like breast cancer, rankings were unstable from cohort to cohort. At the Registry we propose to perform these trend analyses routinely in future, adjusting, when possible, for the effects of deprivation and stage at diagnosis.

Inequalities in access to diabetes care: evidence from a historical cohort study.

OBJECTIVE: To establish which factors predict attendance at a hospital diabetes clinic and for diabetes review in general practice. DESIGN: A historical cohort study of individuals with diabetes identified from general practice records. Information on service contacts and other clinical, social, and demographic variables was collected from general practice records and postal questionnaires. SETTING: Seven Leicestershire general practices. SUBJECTS: Individuals registered with study practices who had a diagnosis of diabetes made before 1990. MAIN OUTCOME MEASUREMENTS: Attendance at a hospital diabetes clinic or for a documented diabetes review in general practice at least once between 1990 and 1995. RESULTS: 124 (20%) had at least one recorded diabetes review in general practice and 332 (54%) attended a hospital diabetes clinic at least once. The main predictors of attending a hospital clinic were younger age, longer duration of diabetes, and treatment with insulin. Access to a car (OR 1.34, 95% CI 1.06 to 1.71), home ownership (OR 1.48, 95% CI 1.14 to 1.58) and a non-manual occupation (OR 1.56, 95% CI 1.09 to 2.24) were all associated with an increased likelihood of attending, although living in a less deprived area was not. The main predictors of attending for review in general practice were older age, less co-morbidity, and being white. Living in a more deprived area was related to a reduced chance of review in general practice (OR 0.81, 95% CI 0.76 to 0.86) while individual socioeconomic indicators were not. CONCLUSIONS: Whilst an indicator of area deprivation predicts reduced likelihood of review in general practice, individual indicators predict reduced likelihood of attending outpatients. This suggests a need for different approaches to tackling inequalities in access to care in primary and secondary care settings.

The 1996 Leicestershire Community Stroke & Ethnicity Study: differences and similarities between South Asian and white strokes.

OBJECTIVE: To estimate the number of strokes in Leicestershire and investigate possible differences between South Asian and white patients. DESIGN: Prospective incidence sample survey. SETTING: Leicestershire. PARTICIPANTS: Acute stroke cases occurring in registered populations of 12 'high Asian' and 11 'low Asian' general practices. RESULTS: The age-specific incidence rates of stroke in Leicestershire were similar to those of the Oxford Community Stroke Project. South Asian patients were less likely to be living alone at home before their stroke and they tended to be younger than whites. However, only 12% of South Asian patients with a stroke were not admitted to hospital within 7 days of their stroke compared to 23% of white patients (chi2 = 3.24, d.f. = 1, P = 0.07). Only 21% of South Asian patients died within 28 days of their stroke compared to 33% of white patients (age-adjusted odds ratio = 0.37; 95% CI: 0.14-0.97). CONCLUSIONS: Overlapping case-finding was crucial to finding all 'possible' strokes and this required close collaborative working between general practices, community health services, hospitals and the health authority. Relatively fewer South Asian patients were managed in the community in the first 7 days. Interestingly, South Asian patients were less likely than white patients to die within 28 days. This is an area worthy of further research.

Do diabetes clinic attendees stay out of hospital? A matched case-control study.

AIMS: To examine whether routine care for diabetes mellitus influences the risk of hospital admission. METHODS: All people with diabetes in five randomly selected general practices in the city of Leicester were identified from medical records and prescribing information. Cases with a hospital admission between 1992 and 1995 but no admission in the preceding 2 years were compared with age-matched controls in a nested study. RESULTS: The variables significantly associated with an increased risk of admission were duration of diabetes in years (OR 1.07, 95% confidence interval (CI) 1.03-1.11) and number of non-diabetic drugs prescribed (OR 1.51, 95% CI 1.27-1.79). Having attended a hospital clinic in the previous 2 years was associated with reduced risk of admission (OR 0.30, 95% CI 0.14-0.65), whilst having been seen for a diabetes review in general practice was not (OR 0.91, 95% CI 0.41-1.99). Similar results were found for both diabetes-related and unrelated admissions. CONCLUSIONS: Although general practice-based review was not associated with a change in the risk of admission, attendance at a hospital clinic was associated with a decreased risk of admission. These results may be explained by the characteristics of those who attend hospital clinics, as well as by the possible effectiveness of access to specialist services in reducing admissions.

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.

Partial remission phase of diabetes in children younger than age 10 years.

There is renewed interest in the phase of partial remission in recently diagnosed diabetes because of the potential for pharmacological and immune intervention to preserve beta cell function. 95 children younger than 10 years were investigated to assess the influence of age, sex, diabetic ketoacidosis (DKA), admission at diagnosis, and ethnicity on the frequency of remission and insulin requirements during the first two years after diagnosis. Partial remission was defined as a requirement of insulin < 0.5 U/kg body weight/day. There was partial remission in 41 patients, with no differences for children aged 2-4 years and those aged 5-9 years. None of the five children aged < 2 years remitted. Forty five of 95 children were admitted to hospital at diagnosis, of whom 26 of 45 had DKA (blood pH < 7.25). In this number of children we were unable to show a statistical difference in the rate of remission with respect to DKA, admission to hospital at diagnosis, sex, or South Asian ethnic background. There were no differences in insulin requirements between the different groups by the end of two years and at that time seven of the children required insulin < 0.5 U/kg/day. The results suggest that even in preschool children there is potential for attempting to preserve beta cell function.

How do individuals with diabetes use the accident and emergency department?

OBJECTIVE: To determine whether the frequency and pattern of use of the accident and emergency (A&E) department by individuals with diabetes is different from that of the general population. METHODS: A historical cohort of 696 individuals with diabetes from six randomly selected general practices and a non-diabetic comparison cohort matched on age, sex, and general practice were identified. The use of an urban A&E department by the two cohorts was compared for number of visits between 1984 and 1996 for injuries, diabetes related and non-diabetes related illness, proportion referred by a general practitioner, proportion arriving by ambulance, and proportion admitted. RESULTS: More visits were made by the diabetic cohort (1002 v 706, P = 0.0001); 121 visits were directly related to diabetes, including 52 for hypoglycaemia. The diabetic cohort also had more visits for medical illness unrelated to diabetes (357 v 231, P = 0.0001). The number of visits for injuries was similar (524 v 475, P = 0.3). Individuals with diabetes who attended A&E were not significantly more likely to be referred by a general practitioner (14% v 16%) or admitted (20% v 17%). CONCLUSIONS: Individuals with diabetes made more frequent visits than the general population to the A&E department. Since there was no excess of visits for injuries and the proportion requiring admission was similar, the hypothesis that they have a different threshold for attending is not supported.

A Survey of the Dietary Management of Children's Diabetes.

A cross-sectional survey of dietitians using a structured postal questionnaire was sent to 148 dietitians who provided a service to children with diabetes. One hundred and twenty-two (82%) replied, of whom 50 were paediatric dietitians (4 paediatric diabetes dietitians) and 72 were other grades. One hundred and eighteen (97%) dietitians reviewed newly diagnosed children within 24-48 hours of diagnosis but only 81 (66%) used literature specifically designed for children. The majority 116 (95%) felt they worked within a multidisciplinary team. Only 15 (12%) dietitians used purely qualitative carbohydrate dietary education; the remainder used quantitative methods, e.g. 10 g exchange system. Ninety-one (75%) used carbohydrate exchange lists. High fibre foods were suggested but dietitians felt only a moderate intake was achievable. One hundred and twelve (92%) recommended a reduced fat intake but guidance was not as unanimous on reducing specific fatty acids. Objective assessment of dietary outcomes was limited. Paediatric dietitians compared with other grades were more likely to use innovative methods of education but no other differences in dietary practice existed. A minority of dietitians 17 (18%) felt families would find implementing the diet easy. The survey confirmed national inconsistencies in dietary messages and poor evaluation of patient compliance. Research is required into effective dietary counselling to support evidence-based practice.

Effectiveness of influenza vaccine in reducing hospital admissions in people with diabetes.

The effectiveness of influenza vaccination in reducing hospitalization of people with diabetes for influenza, pneumonia, or diabetic events during influenza epidemics was assessed in a case control study in Leicestershire, England. Cases were 80 patients on the Leicestershire Diabetes Register who were admitted and discharged from hospital with International Classification of Disease codes for pneumonia, bronchitis, influenza, diabetic ketoacidosis, coma and diabetes, without mention of complications, during the influenza epidemics of 1989-90 and 1993. One hundred and sixty-controls, who were not admitted to hospital during this period, were randomly selected from the Register. Immunization against influenza was assessed in 37 cases and 77 controls for whom consent was obtained to access their clinical notes and for whom notes were available. Significant association was detected between reduction in hospitalization and influenza vaccination during the period immediately preceding an epidemic. Multiple logistic regression analysis estimated that influenza vaccination reduced hospital admissions by 79% (95% CI 19-95%) during the two epidemics, after adjustment for potential confounders.

Death certification: production and evaluation of a training video.

The purpose of this study was to produce an effective training video on death certification suitable for use by medical students and postgraduates. A 15-minute video was commissioned from a video production unit and two authors (PA and CP) provided advice and support in the process of script writing and production. An evaluation by means of a randomized controlled trial took place among 185 first year medical students at the University of Leicester. The video was shown as an addition to the usual lecture on death certification. Performance in a test of knowledge, skill and motivation was recorded in each of the two groups. Students assigned to see the video scored slightly better overall in a test of knowledge and skill (difference in medians = 3, in a test marked out of 68, P = 0.046). The intervention group also gave a significantly higher priority to avoiding distress caused to relatives as a reason for certifying death accurately (60% vs. 35%, difference in proportions = 24%, P = 0.002). There was no evidence that enjoyment or views about the nature or content of the video had an impact on performance in the test. It is concluded that adding the video to the usual lecture had a limited effect on the overall knowledge and skills of undergraduate students but was highly effective in conveying the message that inaccurate death certification can cause distress to relatives. The randomized controlled trial is a practical and simple means of evaluating teaching methods for medical undergraduates.