Jeff R. Flack

Recommended changes to diagnostic criteria for gestational diabetes: Impact on workload

Background:  Gestational diabetes mellitus (GDM) is recognised as a significant problem in pregnancy. Changes to GDM diagnostic criteria have been proposed following analysis of data from the Hyperglycemia and Adverse Pregnancy Outcome (HAPO) study. We sought to assess the impact on the workload for GDM management in Australia that would occur if these changes were adopted.

Risk of tuberculosis among people with diabetes mellitus: an Australian nationwide cohort study

Objective Previous studies that have found an increased risk for tuberculosis (TB) in people with diabetes mellitus (DM) have been conducted in segments of the population and have not adjusted for important potential confounders. We sought to determine the RR for TB in the presence of DM in a national population with data on confounding factors in order to inform the decision-making process about latent tuberculosis infection (LTBI) screening in people with diabetes. Design Whole population historical cohort study. Setting All Australian States and Territories with a mean TB incidence of 5.8/100 000. Participants Cases of TB in people with DM were identified by record linkage using the National Diabetes Services Scheme Database and TB notification databases for the years 2001–2006. Primary and secondary outcome measures Primary outcome was notified cases of TB. Secondary outcome was notified cases of culture-confirmed TB. RR of TB was estimated with adjustment for age, sex, TB incidence in country of birth and indigenous status. Results There were 6276 cases of active TB among 19 855 283 people living in Australia between 2001 and 2006. There were 271 (188 culture positive) cases of TB among 802 087 members of the DM cohort and 130 cases of TB among 273 023 people using insulin. The crude RR of TB was 1.78 (95% CI 1.17 to 2.73) in all people with DM and 2.16 (95% CI 1.19 to 3.93) in people with DM using insulin. The adjusted RRs were 1.48 (95% CI 1.04 to 2.10) and 2.27 (95% CI 1.41 to 3.66), respectively. Conclusions The presence of DM alone does not justify screening for LTBI. However, when combined with other risk factors for TB, the presence of DM may be sufficient to justify screening and treatment for LTBI.

Quality of diabetes care and coronary heart disease absolute risk in patients with type 2 diabetes mellitus in Australian general practice

Objective: To examine the quality of diabetes care and prevention of cardiovascular disease (CVD) in Australian general practice patients with type 2 diabetes and to investigate its relationship with coronary heart disease absolute risk (CHDAR). Methods: A total of 3286 patient records were extracted from registers of patients with type 2 diabetes held by 16 divisions of general practice (250 practices) across Australia for the year 2002. CHDAR was estimated using the United Kingdom Prospective Diabetes Study algorithm with higher CHDAR set at a 10 year risk of >15%. Multivariate multilevel logistic regression investigated the association between CHDAR and diabetes care. Results: 47.9% of diabetic patient records had glycosylated haemoglobin (HbA1c) >7%, 87.6% had total cholesterol ⩾4.0 mmol/l, and 73.8% had blood pressure (BP) ⩾130/85 mm Hg. 57.6% of patients were at a higher CHDAR, 76.8% of whom were not on lipid modifying medication and 66.2% were not on antihypertensive medication. After adjusting for clustering at the general practice level and age, lipid modifying medication was negatively related to CHDAR (odds ratio (OR) 0.84) and total cholesterol. Antihypertensive medication was positively related to systolic BP but negatively related to CHDAR (OR 0.88). Referral to ophthalmologists/optometrists and attendance at other health professionals were not related to CHDAR. Conclusions: At the time of the study the diabetes and CVD preventive care in Australian general practice was suboptimal, even after a number of national initiatives. The Australian Pharmaceutical Benefits Scheme (PBS) guidelines need to be modified to improve CVD preventive care in patients with type 2 diabetes.

Australia's national trends in the incidence of Type 1 diabetes in 0-14-year-olds, 2000-2006.

Aims  To determine the national incidence of Type 1 diabetes in children aged 0–14 years and examine trends in incidence between 2000 and 2006 by age, sex and calendar year.

Sprint Training Increases Muscle Oxidative Metabolism During High-Intensity Exercise in Patients With Type 1 Diabetes

OBJECTIVE—To investigate sprint-training effects on muscle metabolism during exercise in subjects with (type 1 diabetic group) and without (control group) type 1 diabetes. RESEARCH DESIGN AND METHODS—Eight subjects with type 1 diabetes and seven control subjects, matched for age, BMI, and maximum oxygen uptake (V̇o2peak), undertook 7 weeks of sprint training. Pretraining, subjects cycled to exhaustion at 130% V̇o2peak. Posttraining subjects performed an identical test. Vastus lateralis biopsies at rest and immediately after exercise were assayed for metabolites, high-energy phosphates, and enzymes. Arterialized venous blood drawn at rest and after exercise was analyzed for lactate and [H+]. Respiratory measures were obtained on separate days during identical tests and during submaximal tests before and after training. RESULTS—Pretraining, maximal resting activities of hexokinase, citrate synthase, and pyruvate dehydrogenase did not differ between groups. Muscle lactate accumulation with exercise was higher in type 1 diabetic than nondiabetic subjects and corresponded to indexes of glycemia (A1C, fasting plasma glucose); however, glycogenolytic and glycolytic rates were similar. Posttraining, at rest, hexokinase activity increased in type 1 diabetic subjects; in both groups, citrate synthase activity increased and pyruvate dehydrogenase activity decreased; during submaximal exercise, fat oxidation was higher; and during intense exercise, peak ventilation and carbon dioxide output, plasma lactate and [H+], muscle lactate, glycogenolytic and glycolytic rates, and ATP degradation were lower in both groups. CONCLUSIONS—High-intensity exercise training was well tolerated, reduced metabolic destabilization (of lactate, H+, glycogenolysis/glycolysis, and ATP) during intense exercise, and enhanced muscle oxidative metabolism in young adults with type 1 diabetes. The latter may have clinically important health benefits.

Validating self-report of diabetes use by participants in the 45 and up study: a record linkage study

BackgroundPrevalence studies usually depend on self-report of disease status in survey data or administrative data collections and may over- or under-estimate disease prevalence. The establishment of a linked data collection provided an opportunity to explore the accuracy and completeness of capture of information about diabetes in survey and administrative data collections.MethodsBaseline questionnaire data at recruitment to the 45 and Up Study was obtained for 266,848 adults aged 45 years and over sampled from New South Wales, Australia in 2006–2009, and linked to administrative data about hospitalisation from the Admitted Patient Data Collection (APDC) for 2000–2009, claims for medical services (MBS) and pharmaceuticals (PBS) from Medicare Australia data for 2004–2009. Diabetes status was determined from response to a question ‘Has a doctor EVER told you that you have diabetes’ (n = 23,981) and augmented by examination of free text fields about diagnosis (n = 119) or use of insulin (n = 58). These data were used to identify the sub-group with type 1 diabetes. We explored the agreement between self-report of diabetes, identification of diabetes diagnostic codes in APDC data, claims for glycosylated haemoglobin (HbA1c) in MBS data, and claims for dispensed medication (oral hyperglycaemic agents and insulin) in PBS data.ResultsMost participants with diabetes were identified in APDC data if admitted to hospital (79.3%), in MBS data with at least one claim for HbA1c testing (84.7%; 73.4% if 2 tests claimed) or in PBS data through claim for diabetes medication (71.4%). Using these alternate data collections as an imperfect ‘gold standard’ we calculated sensitivities of 83.7% for APDC, 63.9% (80.5% for two tests) for MBS, and 96.6% for PBS data and specificities of 97.7%, 98.4% and 97.1% respectively. The lower sensitivity for HbA1c may reflect the use of this test to screen for diabetes suggesting that it is less useful in identifying people with diabetes without additional information. Kappa values were 0.80, 0.70 and 0.80 for APDC, MBS and PBS respectively reflecting the large population sample under consideration. Compared to APDC, there was poor agreement about identifying type 1 diabetes status.ConclusionsSelf-report of diagnosis augmented with free text data indicating diabetes as a chronic condition and/or use of insulin among medications used was able to identify participants with diabetes with high sensitivity and specificity compared to available administrative data collections.

Acute tubulointerstitial nephritis following treatment with exenatide.

Diabet. Med. 30, 123–125 (2013)

The clinical significance of overt diabetes in pregnancy

To explore clinical implications of overt diabetes in pregnancy on antenatal characteristics, adverse neonatal outcome and diabetes risk post‐partum.

Impact of diabetes on hospital admission and length of stay among a general population aged 45 year or more: a record linkage study

BackgroundThe increased prevalence of diabetes and its significant impact on use of health care services, particularly hospitals, is a concern for health planners. This paper explores the risk factors for all-cause hospitalisation and the excess risk due to diabetes in a large sample of older Australians.MethodsThe study population was 263,482 participants in the 45 and Up Study. The data assessed were linked records of hospital admissions in the 12 months following completion of a baseline questionnaire. All cause and ambulatory care sensitive admission rates and length of stay were examined. The associations between demographic characteristics, socioeconomic status, lifestyle factors, and health and wellbeing and risk of hospitalisation were explored using zero inflated Poisson (ZIP) regression models adjusting for age and gender. The ratios of adjusted relative rates and 95% confidence intervals were calculated to determine the excess risk due to diabetes.ResultsPrevalence of diabetes was 9.0% (n = 23,779). Age adjusted admission rates for all-cause hospitalisation were 631.3 and 454.8 per 1,000 participant years and the mean length of stay was 8.2 and 7.1 days respectively for participants with and without diabetes. In people with and without diabetes, the risk of hospitalisation was associated with age, gender, household income, smoking, BMI, physical activity, and health and wellbeing. However, the increased risk of hospitalisation was attenuated for participants with diabetes who were older, obese, or had hypertension or hyperlipidaemia and enhanced for those participants with diabetes who were male, on low income, current smokers or who had anxiety or depression.ConclusionsThis study is one of the few studies published to explore the impact of diabetes on hospitalisation in a large non-clinical population, the 45 and Up Study. The attenuation of risk associated with some factors is likely to be due to correlation between diabetes and factors such as age and obesity. The increased risk in association with other factors such as gender and low income in participants with diabetes is likely to be due to their synergistic influence on health status and the way services are accessed.

Cardiovascular risk management and its impact in Australian general practice patients with type 2 diabetes in urban and rural areas

Objective:  To investigate the cardiovascular disease (CVD) risk management and its impact on Australian general practice patients with type 2 diabetes in urban and rural areas between 2000 and 2002, and to compare trends over time and differences between urban and rural areas.