Validation of ICD-10-AM Coding for Myocardial Infarction Subtype in Hospitalisation Data.

BACKGROUND: International Classification of Disease (ICD) codes are central for identifying myocardial infarction (MI) in administrative hospitalisation data, however validation of MI subtype codes is limited. We measured the sensitivity and specificity of ICD-10-AM (Australian Modification) codes for ST-elevation MI (STEMI) and non-STEMI (NSTEMI). METHODS: A sample of MI admissions was obtained from a dataset containing all MI hospitalisations in Western Australia (WA) for 2003, 2008 and 2013. Clinical data were collected from hospital medical records (n=799 patients). Cases were classified by ICD-10-AM codes for STEMI, NSTEMI and unspecified MI, and compared to clinical classification from review of available electrocardiographs (ECGs) and cardiac biomarkers (n=660). Sensitivity and specificity for ICD-10-AM coding versus clinical classification was measured, stratified by calendar year of discharge. RESULTS: The majority of classifiable cases had MI recorded in the principal diagnosis field (STEMI n=293, 84.2%; NSTEMI n=202, 74.3%; unspecified MI n=20, 50.0%). Overall sensitivity of the ICD-10-AM STEMI code was 86.3% (95% CI 81.7-90.0%) and was higher when restricted to MI as a principal versus secondary diagnosis (88.8% vs 66.7%). Comparable values for NSTEMI were 66.7% (95% CI 61.5-71.6%), and 68.8% vs 61.4% respectively. Between 2003 and 2013, sensitivity for both MI subtypes increased: 80.2-89.5% for STEMI, and 51.2-73.8% for NSTEMI. Specificity was high for NSTEMI throughout (88.2% 95% CI 84.1-91.6%), although improving over time for STEMI (68.1-76.4%). CONCLUSIONS: The sensitivity and specificity of ICD-10-AM codes for MI subtypes in hospitalisation data are generally high, particularly for principal diagnosis cases. However, the temporal improvement in sensitivity in coding of MI subtypes, particularly NSTEMI, may necessitate modification to trend studies using administrative hospitalisation data.

Improvement in primary school adherence to the NSW Healthy School Canteen Strategy in 2007 and 2010.

ISSUE ADDRESSED: Since 2005, a government-endorsed strategy guiding food sold in New South Wales school canteens has been in place. This study describes the changes in school canteen food between 2007 and 2010 and characterises schools most likely to adhere to strategy guidelines. METHODS: Menus obtained from a cohort of primary and central schools in the Hunter New England region of New South Wales were audited using a traffic light system of classification. Energy dense, nutrient-poor or 'red' items are restricted; 'amber' are to be selected carefully and healthier 'green' items are encouraged. RESULTS: In 2007, 7% of schools had no red items on their menu. In 2010, this improved to 22% (P < 0.05). In 2010, small schools (OR = 1.9, 95% CI = 1.25-3.05, P = 0.003); lower socioeconomic schools (OR = 1.3, 95% CI = 1.02-1.78, P = 0.03); non-government (OR = 1.7, 95% CI = 1.22-2.23, P = 0.001) and rural schools (OR = 1.7, 95% Cl = 1.30-2.25, P < 0.001) had higher odds of having red items on the menu. No significant change occurred in the proportion of green foods listed for sale between 2007 and 2010. CONCLUSIONS: Proportion of schools adhering to strategy guidelines had increased slightly, however, most continue to list red items for regular sale. SO WHAT? For health policies to improve public health they need implementation. Findings suggest more work is required, particularly in small schools, rural schools and non-government schools.

Large Burden of Stroke Incidence in People with Cardiac Disease: A Linked Data Cohort Study.

Purpose: People with cardiac disease have 2-4 times greater risk of stroke than the general population. We measured stroke incidence in people with coronary heart disease (CHD), atrial fibrillation (AF) or valvular heart disease (VHD). Methods: We used a person-linked hospitalization/mortality dataset to identify all people hospitalized with CHD, AF or VHD (1985-2017), and stratified them as pre-existing (hospitalized 1985-2012 and alive at October 31, 2012) or new (first-ever cardiac hospitalization in the five-year study period, 2012-2017). We identified first-ever strokes occurring from 2012 to 2017 in patients aged 20-94 years and calculated age-specific and age-standardized rates (ASR) for each cardiac cohort. Results: Of the 175,560 people in the cohort, most had CHD (69.9%); 16.3% had multiple cardiac conditions. From 2012-17, 5871 first-ever strokes occurred. ASRs were greater in females than males in single and multiple condition cardiac groups, largely driven by rates in females aged ≥75 years, with stroke incidence in this age group being at least 20% greater in females than males in each cardiac subgroup. In females aged 20-54 years, stroke incidence was 4.9-fold greater in those with multiple versus single cardiac conditions. This differential declined with increasing age. Non-fatal stroke incidence was greater than fatal stroke in all age groups except in the 85-94 age group. Incidence rate ratios were up to 2-fold larger in new versus pre-existing cardiac disease. Conclusion: Stroke incidence in people with cardiac disease is substantial, with older females, and younger patients with multiple cardiac conditions, at elevated risk. These patients should be specifically targeted for evidence-based management to minimize the burden of stroke.

HLA polymorphisms and cervical human Papillomavirus infection in a cohort of Montreal University students.

BACKGROUND: Only a minority of women with human papillomavirus (HPV) infection eventually develop cervical cancer, which suggests that host immune mechanisms play a role in the disease. HLA polymorphisms have been linked to the risk of cervical cancer, but very little is known about the role that they play in the acquisition and persistence of HPV infection. METHODS: A cohort study of cervical HPV infections was used to examine the role that 5 HLA alleles (B*07, DQB1*03, DQB1*0602, DRB1*13, and DRB1*1501) play in determining the risk of HPV positivity and persistence in 524 female university students in Montreal. HPV positivity was determined by use of the MY09/11 polymerase-chain-reaction protocol. HLA alleles from purified DNA from cervical specimens were typed by use of a polymerase-chain-reaction technique using sequence-specific primers. RESULTS: HLA DRB1*13 was associated with cumulative risk of HPV infections (odds ratio [OR], 1.7 [95% confidence interval {CI}, 1.0-2.8]), for oncogenic HPV (OR, 1.6 [95% CI, 0.9-2.8]), and for HPV-16 (OR, 2.0 [95% CI, 0.9-4.4]). DQB1*03 was consistently associated with a lower cumulative risk of HPV infections, but this association was not statistically significant. None of the alleles affected the risk of HPV persistence. CONCLUSIONS: The results of this study support the hypothesis that certain HLA class II polymorphisms mediate genetic susceptibility to the acquisition of HPV infection.