Ethnicity and risk of lower limb amputation in people with Type 2 diabetes: a prospective cohort study.

AIM: Lower limb amputation is a serious complication of diabetic foot disease and there are unexplained ethnic variations in incidence. This study investigates the risk of amputation among different ethnic groups after adjusting for demographic, socio-economic status and clinical variables. METHODS: We used primary care data from a large national multi-ethnic cohort of patients with Type 2 diabetes in New Zealand and linked hospital records. The primary outcome was time from initial data collection to first lower limb amputation. Demographic variables included age of onset and duration since diabetes diagnosis, gender, ethnicity and socio-economic status. Clinical variables included smoking status, height and weight, blood pressure, HbA1c , total cholesterol/HDL ratio and albuminuria. Cox proportional hazards models were used. RESULTS: There were 892 lower limb amputations recorded among 62 002 patients (2.11 amputations per 1000 person-years), followed for a median of 7.14 years (422 357 person-years). After adjusting for demographic and socio-economic variables and compared with Europeans, Maori had the highest risk [hazard ratio (HR) 1.84 (95%CI:1.54-2.19)], whereas East Asians [HR 0.18, (0.08-0.44)] and South Asians [HR 0.39 (0.22-0.67)] had the lowest risk. Adjusting for available clinical variables reduced the differences but they remained substantial [HR 1.61 (1.35-1.93), 0.23 (0.10-0.56) and 0.48 (0.27-0.83), respectively]. CONCLUSIONS: Ethnic groups had significantly different risk of lower limb amputation, even after adjusting for demographic and some major clinical risk factors. Barriers to care should be addressed and intensive prevention strategies known to reduce the incidence of lower limb amputations could be prioritized to those at greatest risk.

An association between ethnicity and cardiovascular outcomes for people with Type 2 diabetes in New Zealand.

AIMS: To investigate the association between ethnicity and risk of first cardiovascular (CV) event for people with Type 2 diabetes in New Zealand. METHODS: A prospective cohort study using routinely collected data from a national primary health care diabetes annual review programme linked to national hospital admission and mortality data. Ethnicity was recorded as European, Maori, Pacific, Indo-Asian, East-Asian or Other. A Cox proportional hazards model was used to investigate factors associated with first CV event. Data was collected from 48,444 patients with Type 2 diabetes, with first data collected between 1 January 2000 and 20 December 2005, no previous cardiovascular event at entry and with complete measurements. Risk factors included ethnicity, gender, socio-economic status, body mass index, smoking, age at diagnosis, duration of diabetes, systolic blood pressure, serum lipids, glycated haemoglobin and urine albumin : creatinine ratio. The main outcome measures were time to first fatal or non-fatal CV event. RESULTS: Median follow-up was 2.4 years. Using combined European and Other ethnicities as a reference, hazard ratios for first CV event were 1.30 for Maori (95% confidence interval 1.19-1.41), 1.04 for Pacific (0.95-1.13), 1.06 for Indo-Asian (0.91-1.24) and 0.73 for East-Asian (0.62-0.85) after controlling for all other risk factors. CONCLUSIONS: Ethnicity was independently associated with time to first CV event in people with Type 2 diabetes. Maori were at 30% higher risk of first CV event and East-Asian 27% lower risk compared with European/Other, with no significant difference in risk for Pacific and Indo-Asian peoples.

Early experience with a new model of employer group purchasing in Minnesota.

The Buyers Health Care Action Group (BHCAG) in the Twin Cities has implemented a new purchasing initiative that offers employees a choice among care systems with nonoverlapping networks of primary care providers. These systems offer a standardized benefit package, submit annual bids, and are paid on a risk-adjusted basis. Employees are provided with information on quality and other differences among systems, and most have financial incentives to choose lower-cost systems. Generally, providers have responded favorably to direct contracting and to risk-adjusted payments but have concerns about the risk-adjustment mechanism used and, more importantly, the strength of employers' commitment to the purchasing model.

Valve data collection: problems and pitfalls.

Since 1981, the Department of Medical Physics and Clinical Engineering at the University of Sheffield has been responsible for the organization, management and data collection associated with the largest multicentre heart valve implant patient follow-up study in the Western world. At the present time, the database comprises information on over 16,000 valve implants, which have been provided by 57 surgeons working at 22 centres in the UK. All this data is available for in-depth statistical analysis. Over 30 individual valve models presently are included in the Study and these can be categorized into five main types: ball, disc, porcine, pericardial and homograft. Analysis includes descriptive statistics as well as valuable information on the various performances of the different valves. Survival and event-free survival graphs are obtained by actuarial methods and individual valve types can be studied in depth in terms of freedom from thromboembolic complications and valve dysfunction. Whilst this approach provides interesting and valuable survival data, it does not take account of the wide variation in prognostic factors which occur within large groups of patients. This latter problem can be addressed by the use of proportional hazards analysis and this paper provides details of this approach and typical results obtained from the use of this method. These include the comparative performances of the major types of valves currently in use in terms of the event-free survival of the patients.

n-6 and n-3 fatty acids during early human development.

The food intakes of pregnant women were analysed from two contrasting socio-economic areas in London. There were significant differences in mean calorie and EFA intakes. Analysis of maternal and cord blood essential fatty acids (EFAs) in relation to birth weight, placental weight and head circumference were consistent with the dietary data. To assess the EFA tissue status of the low birth weight babies, the umbilical arteries from 14 separate babies of different birth weights were studied. Surprisingly high levels of the Mead acid (20:3 n-9) were found, with the highest appearing in the artery from the baby with the lowest birth weight. This data may not necessarily imply an EFA deficiency, but at the least it probably indicates a remarkable thirst for long chain n-6 and n-3 fatty acids for fetal brain development.

Morphological assessment of sucrose preservation for porcine heart valves.

Porcine aortic valves stored in various concentrations of sucrose (50-80%) for up to 52 weeks were examined both histologically and by electron microscopy. The valves were compared with porcine aortic valves stored in a nutrient and antibiotic medium for 12 weeks. Overall preservation was better in those porcine valves stored in sucrose solution than in nutrient and antibiotic medium, the best preservation being in 50% sucrose. Despite wide separation of collagen at that concentration seen on electron microscopy (not noted histologically), tissue preservation was good after storage in sucrose solutions at concentrations up to 80%, at which clumping of collagen and distortion of fibroblasts occurred. It is suggested that sucrose solution is acceptable for the long-term preservation of biological valves.

Dietary survey during pregnancy in a low socio-economic group.

Maternal food intakes were assessed by 7-d weighed diet records during the three trimesters of pregnancy in 75 mothers in a low socio-economic groups. Mean (+/- s.e.) energy intakes in the first, second and third trimesters were 1613 +/- 45.7, 1723 +/- 45.4, 1772 +/- 50.2 kcal respectively. Mean (+/- s.e.) energy intakes of nine mothers with babies less than 2500 g at birth were 1446 +/- 95.1 kcal, compared with 1723 +/- 39.9, P less than 0.001. Intake of almost all nutrients was lower in mothers of babies less than 2500 g, but only the difference in fat (62.1 +/- 5.0 vs 72.6 +/- 1.75, P less than 0.025) and pyridoxine (0.92 +/- 0.06 vs 1.47 +/- 0.14, P less than 0.005) intakes reached statistical significance.