Derivation and Validation of a Risk Model for Prediction of Cardiovascular Disease Events in UK Indian Asians



CVD rates are roughly 70% higher among UK Indian Asians compared to European whites, representing a major challenge for NHS and the local health economies where minority ethnic groups are centred. The Imperial College study team have recorded baseline characterisation of 22,623 Indian Asian men and women aged 35-74 years and free from clinically manifest cardiovascular disease (CVD), in the London Life Sciences Prospective Population (LOLIPOP) study.

Indian Asians have been recruited from the lists of 58 GPs in West London, during 2003-7. The Clinical

Informatics team while at St. George’s, prior to their move to University of Surrey, identified 19,060 people, 67.4% of the LOLIPOP cohort of approximately 28K, from primary care records.


Delivery of an integrated programme of research including: Ascertainment of CVD events using routine and electronic data sources

Validation of CVD cases through review of source data (Part relating to Primary Care data)

Health economic analysis of the introduction of the CVD risk prediction calculator for use in Indian Asians Qualitative study to evaluate the visit web site utility and acceptability to general practitioners and individuals of implementing the CVD risk prediction model in general practice (Part related to assessment of risk).


We will integrate two parallel streams of work:

  1. Clinical Informatics: primarily collecting, validating and analysing routine data
  2. Health economic analysis to evaluate the effect of the introduction of a new CVD risk calculation model for Indian Asians. These streams of work commenced in March 2010, with our first data extraction and will run through to March 2013. We will develop full protocols and seek permission through NRES (National Research Ethics Service) to conduct the extension of these studies to extract additional anonymised data to assess any bias in the treatment of people in the LOLIPOP cohort.


Possible CVD events identified through follow-up, death certification, routine and clinical databases will be validated against source data.

Suggested data sources include: coroner’s reports, hospital and primary care records where available.

Events will initially be coded by a researcher, according to written, internationally accepted criteria. We will need to develop a process of scrutiny to ensure the validity of this process.


We will visit and re-establish our relationship with participating practices to facilitate the conduct of a data validation exercise. We have previously conducted very similar studies1. We will pilot this out of area (Surrey) and then run it in west London.

Once permissions are in place to access hospital records we would target records where no hospital record of an event; or where there was a diagnosis we are unable to triangulate by finding appropriate therapy/observations.

We will include a sensitivity analysis looking at therapy/test results we would expect to be associated with a vascular diagnosis but one is not present in the records (e.g. Prescription of a nitrate where there is not CVD diagnosis). Further information about how we go about validating diagnoses can be found in our diabetes work, carried out with RCGP and NHS Diabetes (See: )

We aim to develop a system which enables us to record CVD events in the pilot (west London). The data collection validation will take place between the third quarter of 2012 and first quarter of 2013.