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Stroke

Evangelos Kontopantelis, Ivan Olier, Claire Planner, David Reeves, Darren M Ashcroft, Linda Gask, Tim Doran, Sioban Reilly

Type
Disease or Syndrome
ID
PH564
Version ID
1128
Data Sources
Valid event data range
01/04/2000 - 31/03/2012
Sex
Female, Male
Agreement Date
2015-12-16
Coding system
Read codes v2 OXMIS codes
Tags /Collections
ClinicalCodes Repository Phenotype Library

Definition

The database:

The CPRD is a large computerised database of anonymised primary care medical records. It contains complete patient information for participating practices, with the healthcare events (diagnoses, treatments, referrals, tests and prescriptions) recorded using coding systems (Read coding for diagnoses). Practice characteristics are described in detail elsewhere. The database is broadly representative of the UK population, although larger practices are over-represented. Practices need to meet prespecified data entry quality criteria to be defined as ‘up to research standard’, and for each study year, our main sample included all CPRD practices that were classed as such for the whole year. We also generated two data sets to test the sensitivity of our findings. First, we included all practices contributing data across the entire study period. Second, we included a subsample of 50 practices, representative of UK practices in terms of area deprivation, and practice list size.

Defining people with SMI and controls:

Information was extracted for the period 1 April 2000 to 31 March 2012 and aggregated into 12 yearly ‘bins’, to correspond with financial years 2000/2001–2011/2012. We used Read codes to identify the presence of SMI. First, we identified relevant keywords (or key-stubs) and codes, for example ‘paranoi’ and ‘E100.00’ (simple schizophrenia). Next, the CPRD was searched for codes that matched the list in either the code or the description field. Finally, the matched code list was reviewed by clinical experts and a final conservative list of codes was agreed. A similar process was used to define comorbidities (hypertension, asthma, hypothyroidism, osteoarthritis, chronic kidney disease, coronary heart disease, epilepsy, chronic obstructive pulmonary disease, cancer, stroke, heart failure, rheumatoid arthritis, dementia and psoriasis). All code lists we used are available from http://www.clinicalcodes.org. All conditions, bar asthma, were treated as unresolvable (ie, permanent). Within each year, all patients registered with a CPRD practice for the whole year and aged 18 or over were eligible for inclusion. The final SMI Read code list was used to identify cases of SMI, which were then grouped into three broad subcategories, in line with the diagnoses used when compiling primary care QOF SMI registers: schizophrenia; affective psychoses (bipolar disorder or other unspecified affective psychosis); other types of psychosis. In the event that an individual received more than one SMI diagnosis over the study period, we used the last available diagnosis to retrospectively ‘correct’ the original diagnosis (ie, we assumed that the latest diagnosis was the correct one). Within each year, each SMI case was then matched on age, sex and practice to five randomly selected patients not associated with SMI up until that time point. More details on the extraction of the cohort have been provided elsewhere,21 and a flow chart of the data extraction process is available in the online appendix figure A2.

Defining consultation type:

We defined a ‘consultation’ as involving direct contact between a patient and a healthcare professional within the primary care setting. We divided consultations into two main categories: face-to-face (our primary outcome), and by telephone (see online appendix table A1). We also constructed a third ‘other’ grouping of all other activities that are captured by the ‘consultation type’ codes within the CPRD. This includes mail/email contact, third party consultations (including referrals), secondary care episodes, other administrative tasks and consultations of unknown content. This group is highly heterogeneous and includes many activities that cannot be classed as consultations. However, we decided to use this grouping as an aggregate secondary outcome since it can potentially provide insight into the overall workload associated with patient care in the primary care context. We decided against breaking down the ‘other’ group in more subcategories as we are very doubtful regarding the reliability and across practice consistency of the coding within these ‘other’ categories. In instances where a patient had two or more consultations within a day, we conservatively assumed a single consultation took place, to reduce the likelihood of including duplicate records.

Publications

  • Evangelos Kontopantelis, Ivan Olier, Claire Panner, David Reeves, Darren M Ashcroft, Linda Gask, Tim Doran, Siobhan Reilly, Primary care consultation rates among people with and without severe mental illness a UK cohort study using the Clinical Practice Research Datalink. BMJ Open, 5 (e008650), 2015.

Clinical Code List

Rows: 75
Code Description Entity type Coding System (OXMIS Read) Category
G61..00 Intracerebral haemorrhage res21: Stroke Read diagnostic
G61..11 CVA - cerebrovascular accid due to intracerebral haemorrhage res21: Stroke Read diagnostic
G61..12 Stroke due to intracerebral haemorrhage res21: Stroke Read diagnostic
G610.00 Cortical haemorrhage res21: Stroke Read diagnostic
G611.00 Internal capsule haemorrhage res21: Stroke Read diagnostic
G612.00 Basal nucleus haemorrhage res21: Stroke Read diagnostic
G613.00 Cerebellar haemorrhage res21: Stroke Read diagnostic
G614.00 Pontine haemorrhage res21: Stroke Read diagnostic
G615.00 Bulbar haemorrhage res21: Stroke Read diagnostic
G616.00 External capsule haemorrhage res21: Stroke Read diagnostic
G618.00 Intracerebral haemorrhage, multiple localized res21: Stroke Read diagnostic
G61X.00 Intracerebral haemorrhage in hemisphere, unspecified res21: Stroke Read diagnostic
G61X000 Left sided intracerebral haemorrhage, unspecified res21: Stroke Read diagnostic
G61X100 Right sided intracerebral haemorrhage, unspecified res21: Stroke Read diagnostic
G61z.00 Intracerebral haemorrhage NOS res21: Stroke Read diagnostic
G63y000 Cerebral infarct due to thrombosis of precerebral arteries res21: Stroke Read diagnostic
G63y100 Cerebral infarction due to embolism of precerebral arteries res21: Stroke Read diagnostic
G64..00 Cerebral arterial occlusion res21: Stroke Read diagnostic
G64..11 CVA - cerebral artery occlusion res21: Stroke Read diagnostic
G64..12 Infarction - cerebral res21: Stroke Read diagnostic
G64..13 Stroke due to cerebral arterial occlusion res21: Stroke Read diagnostic
G640.00 Cerebral thrombosis res21: Stroke Read diagnostic
G640000 Cerebral infarction due to thrombosis of cerebral arteries res21: Stroke Read diagnostic
G641.00 Cerebral embolism res21: Stroke Read diagnostic
G641.11 Cerebral embolus res21: Stroke Read diagnostic
G641000 Cerebral infarction due to embolism of cerebral arteries res21: Stroke Read diagnostic
G64z.00 Cerebral infarction NOS res21: Stroke Read diagnostic
G64z.11 Brainstem infarction NOS res21: Stroke Read diagnostic
G64z.12 Cerebellar infarction res21: Stroke Read diagnostic
G64z000 Brainstem infarction res21: Stroke Read diagnostic
G64z100 Wallenberg syndrome res21: Stroke Read diagnostic
G64z111 Lateral medullary syndrome res21: Stroke Read diagnostic
G64z200 Left sided cerebral infarction res21: Stroke Read diagnostic
G64z300 Right sided cerebral infarction res21: Stroke Read diagnostic
G64z400 Infarction of basal ganglia res21: Stroke Read diagnostic
G65..00 Transient cerebral ischaemia res21: Stroke Read diagnostic
G65..11 Drop attack res21: Stroke Read diagnostic
G65..12 Transient ischaemic attack res21: Stroke Read diagnostic
G65..13 Vertebro-basilar insufficiency res21: Stroke Read diagnostic
G650.00 Basilar artery syndrome res21: Stroke Read diagnostic
G650.11 Insufficiency - basilar artery res21: Stroke Read diagnostic
G651.00 Vertebral artery syndrome res21: Stroke Read diagnostic
G651000 Vertebro-basilar artery syndrome res21: Stroke Read diagnostic
G652.00 Subclavian steal syndrome res21: Stroke Read diagnostic
G653.00 Carotid artery syndrome hemispheric res21: Stroke Read diagnostic
G654.00 Multiple and bilateral precerebral artery syndromes res21: Stroke Read diagnostic
G656.00 Vertebrobasilar insufficiency res21: Stroke Read diagnostic
G65y.00 Other transient cerebral ischaemia res21: Stroke Read diagnostic
G65z.00 Transient cerebral ischaemia NOS res21: Stroke Read diagnostic
G65z000 Impending cerebral ischaemia res21: Stroke Read diagnostic
G65z100 Intermittent cerebral ischaemia res21: Stroke Read diagnostic
G65zz00 Transient cerebral ischaemia NOS res21: Stroke Read diagnostic
G66..00 Stroke and cerebrovascular accident unspecified res21: Stroke Read diagnostic
G66..11 CVA unspecified res21: Stroke Read diagnostic
G66..12 Stroke unspecified res21: Stroke Read diagnostic
G66..13 CVA - Cerebrovascular accident unspecified res21: Stroke Read diagnostic
G660.00 Middle cerebral artery syndrome res21: Stroke Read diagnostic
G661.00 Anterior cerebral artery syndrome res21: Stroke Read diagnostic
G662.00 Posterior cerebral artery syndrome res21: Stroke Read diagnostic
G663.00 Brain stem stroke syndrome res21: Stroke Read diagnostic
G664.00 Cerebellar stroke syndrome res21: Stroke Read diagnostic
G665.00 Pure motor lacunar syndrome res21: Stroke Read diagnostic
G666.00 Pure sensory lacunar syndrome res21: Stroke Read diagnostic
G667.00 Left sided CVA res21: Stroke Read diagnostic
G668.00 Right sided CVA res21: Stroke Read diagnostic
G6W..00 Cereb infarct due unsp occlus/stenos precerebr arteries res21: Stroke Read diagnostic
G6X..00 Cerebrl infarctn due/unspcf occlusn or sten/cerebrl artrs res21: Stroke Read diagnostic
Gyu6200 [X]Other intracerebral haemorrhage res21: Stroke Read diagnostic
Gyu6300 [X]Cerebrl infarctn due/unspcf occlusn or sten/cerebrl artrs res21: Stroke Read diagnostic
Gyu6400 [X]Other cerebral infarction res21: Stroke Read diagnostic
Gyu6500 [X]Occlusion and stenosis of other precerebral arteries res21: Stroke Read diagnostic
Gyu6600 [X]Occlusion and stenosis of other cerebral arteries res21: Stroke Read diagnostic
Gyu6G00 [X]Cereb infarct due unsp occlus/stenos precerebr arteries res21: Stroke Read diagnostic
L440.11 CVA - cerebrovascular accident in the puerperium res21: Stroke Read diagnostic
L440.12 Stroke in the puerperium res21: Stroke Read diagnostic
Rows: 9
Code Description Entity type Coding System (OXMIS Read) Category
4350AT TRANSIENT ISCHAEMIC ATTACKS WITH HYPERTE res21: Stroke OXMIS diagnostic
4359AT TRANSIENT ISCHAEMIC ATTACKS res21: Stroke OXMIS diagnostic
4360A CEREBROVASCULAR ACCIDENT WITH HYPERTENSI res21: Stroke OXMIS diagnostic
4360B STROKE WITH HYPERTENSION res21: Stroke OXMIS diagnostic
4369A CVA (CEREBROVASCULAR ACCIDENT) res21: Stroke OXMIS diagnostic
4369AL CEREBROVASCULAR ACCIDENT LEFT res21: Stroke OXMIS diagnostic
4369AR CEREBROVASCULAR ACCIDENT RIGHT res21: Stroke OXMIS diagnostic
4369B STROKE res21: Stroke OXMIS diagnostic
4369BN SYNDROME STROKE res21: Stroke OXMIS diagnostic

API

To Export Phenotype Details:

Format API
XML site_root/api/v1/public/phenotypes/PH564/version/1128/detail/?format=xml
JSON site_root/api/v1/public/phenotypes/PH564/version/1128/detail/?format=json
R Package

# Download here

library(ConceptLibraryClient)


# Connect to API

client = connect_to_API(public=TRUE)


# Get details of phenotype

details = get_phenotype_detail_by_version('PH564', '1128', api_client=client)

To Export Phenotype Code List:

Format API
XML site_root/api/v1/public/phenotypes/PH564/version/1128/export/codes/?format=xml
JSON site_root/api/v1/public/phenotypes/PH564/version/1128/export/codes/?format=json
CSV site_root/phenotypes/PH564/version/1128/export/codes/
R Package

# Download here

library(ConceptLibraryClient)


# Connect to API

client = connect_to_API(public=TRUE)


# Get codelists of phenotype

codelists = get_phenotype_code_list('PH564', '1128', api_client=client)

Version History

Version
ID
Name Owner Publish date
1128 Stroke ieuan.scanlon 2021-10-06 currently shown

Export - export all codes into a csv file/JSON/XML for the current phenotype version.

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