Transient ischaemic attack and ischaemic stroke: constructing episodes of care using hospital claims data

[Trends in stroke mortality rates in Russia and the USA over a 15-year period]

AIM

to comparatively analyze standardized mortality ratios (SMR) from stroke in the populations aged over 30 years in the Russian Federation and in the USA over a 15-year period.

MATERIAL AND METHODS

The analysis included nontraumatic subarachnoid hemorrhage (NTSH) (a group of ICD-10 codes I60), nontraumatic intracerebral hemorrhage (NTIH) (I61), cerebral infarction (CI) (I63), and stroke, not specified as hemorrhage or infarction (SNSHI) (I64). The new European standard (European Standard Population.2013) was used for standardization. The data of the Federal State Statistics Service of the Russian Federation, those of the World Health Organization Mortality Database (WHO MD) and Human Mortality Database (HMD) for the USA were applied.

RESULTS

During the considered period, 30-49-year-old Russian men showed a reduction in SMRs from NTSH (I61) by 9.0% (from 18.9 to 17.2 per 100,000 population), from SNSHI (I64) by 10 times (from 12.5 to 1.3); SMRs from CI (I63) increased by 4.3% (from 6.9 to 7.2). In men aged 50 years and older, SMRs from NTIH and SNSHI decreased by 32.3% (from 143.2 to 97.0) and by 10 times (from 580.8 to 60.6), respectively; those from CI increased by 13.8% (from 229.8 to 261.4). In the USA, 30-49-year-old men displayed 26.1% and 2-fold decreases in SMRs from NTIH (from 2.5 per 100,000 population in 1999 to 1.7 in 2013) and CI (from 1.8 to 0.9), respectively; those from SNSHI remained unchanged (1.3). In men aged 50 years and older, SMRs from NTIH, CI, and SNSHI reduced by 39.7% (from 29.0 to 17.5), by 2 times (from 1.8 to 0.9), and by 2 times (143.0 to 72.5), respectively. 30-49-year-old Russian women exhibited a 22.2% reduction in SMRs from NTIH (from 9.0 to 7.0), a 4.3% increase in those from CI (from 2.7 to 2.8), and an 11-fold decrease in those from SNSHI (from 5.5 to 0.5). Women aged 50 years and older showed changes in SMRs from the codes in the same sequence from 105.6 to 60.5, from 172.8 to 189.6, and from 466.5 to 43.7, respectively. In the USA, 30-49-year-old women displayed reductions in SMRs from NTIH by 10.0% (from 1.5 to 0.9), from CI by 33.3% (from 0.3 to 0.2), and from SNSHI by 10% (from 1.0 to 0.9). Women aged 50 years and older exhibited changes in SMRs from the codes in the same sequence from 24.0 to 14.8), n those from CI (from 20.6 to 6.7) and from SNSHI (from 6.5 to 10.3).

CONCLUSION

In Russia, the reduction in mortality rates from the above causes (which is most significant from that in NTSH may be associated with both medical and socioeconomic factors, including with the improved prevention and organization of medical care. The differences in SMRs between the two countries may be related to the principles in the organization and control of coding of the causes of death.

The '6W' multidimensional model of care trajectories for patients with chronic ambulatory care sensitive conditions and hospital readmissions

OBJECTIVES

To synthesize concepts and approaches related to the analysis of patterns or processes of care and patient's outcomes into a comprehensive model of care trajectories, focusing on hospital readmissions for patients with chronic ambulatory care sensitive conditions (ACSCs).

STUDY DESIGN

Narrative literature review.

METHODS

Published studies between January 2000 and November 2017, using the concepts of 'continuity', 'pathway', 'episode', and 'trajectory', and focused on readmissions and chronic ACSCs, were collected in electronic databases. Qualitative content analysis was performed with emphasis on key constituents to build a comprehensive model.

RESULTS

Specific common constituents are shared by the concepts reviewed: they focus on the patient, aim to measure and improve outcomes, follow specific periods of time and consider other factors related to care providers, care units, care settings, and treatments. Using these common denominators, the comprehensive '6W' multidimensional model of care trajectories was created. Considering patients' attributes and their chronic ACSCs illness course ('who' and 'why' dimensions), this model reflects their patterns of health care use across care providers ('which'), care units ('where'), and treatments ('what'), at specific periods of time ('when').

CONCLUSIONS

The '6W' model of care trajectories could provide valuable information on 'missed opportunities' to reduce readmission rates and improve quality of both ambulatory and inpatient care.

The representativeness of direct oral anticoagulant clinical trials to hospitalized patients with atrial fibrillation

PURPOSE

Trials of the direct oral anticoagulants (DOACs) dabigatran, rivaroxaban and apixaban provide the basis for prescribing for the prevention of stroke and systemic embolism in atrial fibrillation (AF). The objective of this study was to assess the representativeness of the three pivotal DOAC randomized controlled trials of dabigatran, rivaroxaban and apixaban for unselected hospitalized patients with AF.

METHODS

A cross-sectional study was undertaken. All patients discharged with AF between 2012 and 2015 from a large public hospital network in Melbourne, Australia, were identified. Inclusion and exclusion criteria from the DOAC trials were applied. The proportions of hospitalized patients with AF who would have been eligible for the dabigatran (RE-LY), rivaroxaban (ROCKET-AF) and apixaban (ARISTOTLE) trials were estimated, as was pooled eligibility for all three trials. Characteristics of eligible and ineligible patients were compared.

RESULTS

For the 4734 patients, application of the inclusion and exclusion criteria resulted in 60.5, 52.6 and 35.8% eligibility for the trials of apixaban, dabigatran and rivaroxaban, respectively. Pooled eligibility across all three trials demonstrated that 33.4% of the patients would have been eligible for all three trials but 36.7% ineligible for any trial. Ineligible patients who met exclusion criteria were older and experienced more comorbidities.

CONCLUSIONS

The apixaban and dabigatran trials may be the most representative of hospitalized patients with AF. The DOAC trial results can readily be extrapolated to, and guide prescribing for, at least two thirds of patients discharged from a large metropolitan health service in Australia.

Differentiating Incident from Recurrent Stroke Using Administrative Data: The Impact of Varying Lengths of Look-Back Periods on the Risk of Misclassification

BACKGROUND/AIMS

Administrative data are widely used to monitor epidemiological trends in stroke and outcomes; yet there is scant empirical guidance on how to best differentiate incident from recurrent stroke.

METHODS

We identified all hospital admissions in New South Wales, Australia, with a principal stroke diagnosis from July 1, 2013 to June 30, 2014, linked to 12 years of previous admissions. We calculated the proportion of cases identified with a prior stroke to determine the number of years of look-back required to minimise misclassification of incident and recurrent strokes.

RESULTS

Using the maximum available look-back period of 12 years, 1,171 out of 8,364 eligible stroke cases (14.0%) had a stroke history. A 1-year look-back period identified only 25.1% of these patients and 1 in 10 stroke cases were misclassified as incident. With a 10-year clearance period, less than 1 in 100 stroke cases were misclassified as incident. The risk of misclassification was lower in patients younger than 65 years and in those with haemorrhagic stroke.

CONCLUSION

Hospital administrative data sets linked to prior admissions can be used to distinguish recurrent from incident stroke. The risk of misclassifying recurrent stroke cases as incident events is negligible with a look-back period of 10 years.

Medicines taken by older Australians after transient ischaemic attack or ischaemic stroke: a retrospective database study

BACKGROUND

Guidelines recommend patients diagnosed with transient ischaemic attack (TIA) or ischaemic stroke receive antihypertensive, antithrombotic and lipid lowering medicines. Reassessment of the need for medicines associated with an increased risk of stroke is also recommended.

OBJECTIVE

To determine changes in the use of medicines recommended for secondary stroke prevention, medicines commonly used for treating stroke-related complications and medicines not recommended for use after ischaemic stroke, and to determine patient characteristics associated with use of all three stroke prevention medicines after TIA or ischaemic stroke. Setting Administrative health claims data from the Australian Government Department of Veterans' Affairs.

METHOD

This retrospective study included patients with a first-ever hospitalisation for TIA or ischaemic stroke in 2009 and alive at 4 months after discharge. Changes to medicines dispensed in the 4 months before and after hospitalisation were compared using McNemar's test. Log binomial regression analysis was used to determine patient characteristics associated with use of all three secondary stroke prevention medicines after hospitalisation for TIA or ischaemic stroke.

MAIN OUTCOME MEASURE

Prevalence of medicine use after hospitalisation.

RESULTS

1541 patients (853 TIA, 688 ischaemic stroke) were included, with a median age of 85 years. High use of antihypertensive (82% TIA, 86 % ischaemic stroke) and antithrombotic (84% TIA, 90% ischaemic stroke) medicines was observed postdischarge, with 58% of TIA and 73% of ischaemic stroke patients receiving lipid lowering therapy. Half of the population (47% TIA, 61% ischaemic stroke) were dispensed all three classes of medicines recommended for secondary stroke prevention after discharge. Ischaemic stroke patients, younger patients, patients with more comorbid conditions and those discharged home were more likely to receive all three recommended medicine classes. Antibiotics (45% TIA, 46% ischaemic stroke), paracetamol (44% TIA, 47% ischaemic stroke), antidepressants (26% TIA, 31% ischaemic stroke) and laxatives (24% TIA, 32% ischaemic stroke) were commonly used after discharge. Increased use of sedatives and reduced use of non-steroidal anti-inflammatories was also observed after discharge.

CONCLUSION

Changes to pharmacotherapy after TIA or ischaemic stroke were consistent with treatment for stroke risk factors and common stroke-related complications. Use of secondary stroke prevention medicines may be further improved among TIA patients.

Antithrombotic use following transient ischaemic attack or ischaemic stroke among older Australians with atrial fibrillation

Hospital audits may underestimate anticoagulant use among acute ischaemic stroke patients with atrial fibrillation (AF), as treatment may commence after discharge. To account for this, antithrombotic use in the 4 months after hospitalisation for transient ischaemic attack or ischaemic stroke among AF patients was assessed using claims data. Results suggest that treatment may be commenced soon after discharge and should be considered when assessing prevalence of use.