New principles for primary prevention of cardiovascular disease: the targeted measurement of lipids
The UK is currently in the process of rolling out a major primary prevention programme for CVD, the NHS Health Check programme. Under guidance for the
programme, only patients "at high risk of having or developing diabetes need a blood sugar test.1" Likewise not all patients
require serum creatinine tests; however all must have lipid levels assessed. We investigated, using data from patient medical records in NHS Ealing,2 the need for measurement of lipid levels in low risk patients. Using data from 73,853 patients aged 40-74, we applied the QRISK2 3 algorithm, firstly replacing lipid data with age and sex estimates from the Health Survey for England (HSfE), and secondly using the
complete patient data. We compared risk classification between methods, the former representing data from general practice without lipid measurement.
Using the HSfE data, 27,682 (37.5%) (table) patients aged 40-74 were designated as at <5% risk, of whom none were shown to be at high risk once
using complete patient data. A further 13,170 (17.8%) were estimated at 5-10% risk, of whom only 11 became >20%.
CVD risk score using estimated lipid data
<5%
5-10%
10-15%
15-20%
>20%
Total
CVD risk score using lipid data
<10%
27,682
13,170
1,528
0
0
42,380
10-20%
3
1,626
8,219
6,144
1,666
17658
>20%
0
11
136
1,292
12,376
13815
Total
27,685
14,807
9,883
7,436
14,042
73,853
Of the near 23 million people in England aged 40-74, the Department of Health estimates 15 million are eligible for Health Checks.4 Given
our estimates of the proportion <5% risk and a cost of ?4.20 per lipid test,4 approaching ?24 million will be spent every five years on
lipid tests in patients at the lowest risk. We question the utility of lipid tests in all patients during a Health Check. A number of patients will
already have valid lipid recorded in their medical records,2 whilst for those at the lowest risk lipid values add limited information
concerning their risk profile. Although cardiovascular risk should not be considered a dichotomy, there is little evidence that risk scores have the
precision to discriminate between low levels of risk. Familial hyperlipidaemia is an important mediator of vascular risk; however family history of
coronary heart disease should be the important driver in diagnoses.5 Lipid testing has been discussed as a "hook" for Health Checks to
promote attendance; however this has no supporting evidence. With increased strain upon NHS spending, methods of risk stratification within the NHS
Health Checks may have the potential to reduce programme costs.
Ethical approval: London LREC
References
(1) Department of Health. Putting Prevention First- Vascular checks: risk assessment and management- next steps guidance for primary care trusts.
2009 London, England,
(2) Dalton ARH, Bottle A, Okoro C, Majeed A, Millett C. Implementation of the NHS Health Checks programme: baseline assessment of risk factor
recording in an urban culturally diverse setting. Fam Pract 2010; 28(1):34-40.
(3) Hippisley-Cox J, Coupland C, Vinogradova Y, et al. Predicting cardiovascular risk in England and Wales: prospective derivation and validation
of QRISK2. British Medical Journal 2008; 336(7659):1475.
(4) Department of Health. Economic Modelling for Vascular Checks. 2008 London, England.
(5) National Institute of Clinical Excellence. Identification and management of familial hypercholesterolaemia; Clininical guidance 71. 2008
London, England.
Rapid Response:
New principles for primary prevention of cardiovascular disease: the targeted measurement of lipids
The UK is currently in the process of rolling out a major primary prevention programme for CVD, the NHS Health Check programme. Under guidance for the
programme, only patients "at high risk of having or developing diabetes need a blood sugar test.1" Likewise not all patients
require serum creatinine tests; however all must have lipid levels assessed. We investigated, using data from patient medical records in NHS Ealing,2 the need for measurement of lipid levels in low risk patients. Using data from 73,853 patients aged 40-74, we applied the QRISK2 3 algorithm, firstly replacing lipid data with age and sex estimates from the Health Survey for England (HSfE), and secondly using the
complete patient data. We compared risk classification between methods, the former representing data from general practice without lipid measurement.
Using the HSfE data, 27,682 (37.5%) (table) patients aged 40-74 were designated as at <5% risk, of whom none were shown to be at high risk once
using complete patient data. A further 13,170 (17.8%) were estimated at 5-10% risk, of whom only 11 became >20%.
CVD risk score using estimated lipid data
<5%
5-10%
10-15%
15-20%
>20%
Total
CVD risk score using lipid data
<10%
27,682
13,170
1,528
0
0
42,380
10-20%
3
1,626
8,219
6,144
1,666
17658
>20%
0
11
136
1,292
12,376
13815
Total
27,685
14,807
9,883
7,436
14,042
73,853
Of the near 23 million people in England aged 40-74, the Department of Health estimates 15 million are eligible for Health Checks.4 Given
our estimates of the proportion <5% risk and a cost of ?4.20 per lipid test,4 approaching ?24 million will be spent every five years on
lipid tests in patients at the lowest risk. We question the utility of lipid tests in all patients during a Health Check. A number of patients will
already have valid lipid recorded in their medical records,2 whilst for those at the lowest risk lipid values add limited information
concerning their risk profile. Although cardiovascular risk should not be considered a dichotomy, there is little evidence that risk scores have the
precision to discriminate between low levels of risk. Familial hyperlipidaemia is an important mediator of vascular risk; however family history of
coronary heart disease should be the important driver in diagnoses.5 Lipid testing has been discussed as a "hook" for Health Checks to
promote attendance; however this has no supporting evidence. With increased strain upon NHS spending, methods of risk stratification within the NHS
Health Checks may have the potential to reduce programme costs.
Ethical approval: London LREC
References
(1) Department of Health. Putting Prevention First- Vascular checks: risk assessment and management- next steps guidance for primary care trusts.
2009 London, England,
(2) Dalton ARH, Bottle A, Okoro C, Majeed A, Millett C. Implementation of the NHS Health Checks programme: baseline assessment of risk factor
recording in an urban culturally diverse setting. Fam Pract 2010; 28(1):34-40.
(3) Hippisley-Cox J, Coupland C, Vinogradova Y, et al. Predicting cardiovascular risk in England and Wales: prospective derivation and validation
of QRISK2. British Medical Journal 2008; 336(7659):1475.
(4) Department of Health. Economic Modelling for Vascular Checks. 2008 London, England.
(5) National Institute of Clinical Excellence. Identification and management of familial hypercholesterolaemia; Clininical guidance 71. 2008
London, England.
Competing interests: No competing interests