Re: Government prioritises health checks for 15 million adults despite pre-election promise to scrap them
In his assessment of the BMJ version of our Cochrane review on general health checks,(1) Michael Caley has confused the year of trial start with the year of publication, although we had stated this clearly in tables 1, 2, and 3, in the legends for the meta-analysis (figures 6, 7, and 8), and on page 4. The publication years for the mortality results are as follows: 1977, 1977, 1982, 1986, 1986, 1986, 1998, and 2005. For the OXCHECK trial (that ran from 1989 to 1993), we got unpublished mortality results from the authors. It is therefore wrong when Michael Caley claims that most studies reported results before 1971.
The assertion that our review does not indicate what happened during the health checks is also wrong. We dedicated a page-size table (table 3) to give an overview of the tests used, and table 1 describes other important features, e.g. where the health checks took place, whether a lifestyle intervention was included and the number of health checks offered. The corresponding Cochrane review gives even more detail on the health checks, such as the exact blood tests used and the type of lifestyle intervention.
We did not select trials on the basis of the type of follow-up used. Most trials did not specify which treatments were used and in some, participants with identified abnormalities were referred to their primary care physician for follow-up. However, this certainly cannot be interpreted as if a treatment was not given, as the trials were conducted in an era with a focus on treatment of risk factors (contrary to what Caley asserts). The statement that "no reference is made to any medical treatment being given", is also wrong, as we mentioned the possibility of bias (favouring the intervention) from trials using follow-up by specialists or by specific treatment algorithms ('Risk of bias', lines 16-20).
Michael Caley's optimism about health checks today is not only unwarranted, it is in direct conflict with the best available evidence. Although he is correct that several interventions for reducing cardiovascular risk have well-documented efficacy, it is not a given that these perform as well in the context of population-based health checks. An important feature of many of the trials we reviewed was their pragmatic design: no exclusion criteria, no run-in periods, and realistic follow-up, rather than the frequent monitoring seen in some drug trials, which may affect treatment compliance. Self-selection is a strong factor in health checks, and participants tend to have better risk profiles,(2) higher socio-economic status,(3) and lower morbidity(4) and mortality.(5) Thus, health checks tend to reach those who need them the least, reducing any benefits on a population level, while maintaining the harms, i.e. the inevitable overdiagnosis and overtreatment.
Another reason for trusting the trials we reviewed is that they had very little industry funding, in contrast to many drug trials. Given the high level of secrecy surrounding the industry's trial data, and given the abundant evidence of misrepresentation of research findings and even fraud in some industry trials,(6) it is possible that the balance between benefit and harm may be less favourable under real life conditions. Even worse, diabetes drugs were approved on the basis of surrogate outcomes for decades,(7) even though tolbutamide was shown to increase cardiovascular mortality compared to placebo or insulin, already in 1970.
Finally, we note that, although lifestyle interventions may impact positively on risk factors, they do not seem to have convincing effects on morbidity and mortality in general populations,(8) and while treatment of moderate or severe hypertension is beneficial, treatment of mild hypertension has not been shown to be so.(9)
Thus, there are plenty of possible explanations for the disappointing effects of health checks in the trials, and in the absence of evidence to the contrary, there is no reason to assume that the NHS Health Check is any better.
The large Inter99 trial of health checks and lifestyle intervention, with 10 years of follow-up, recently presented results, and they are in line with our results.
Lasse T Krogsbøll
Karsten Juhl Jørgensen
Peter C Gøtzsche
1. Krogsbøll LT, Jørgensen KJ, Grønhøj Larsen C, Gøtzsche PC. General health checks in adults for reducing morbidity and mortality from disease: Cochrane systematic review and meta-analysis. BMJ 2012;345:e7191.
2. Waller D, Agass M, Mant D, Coulter A, Fuller A, Jones L. Health checks in general practice: another example of inverse care? BMJ 1990;300:1115–8.
3. Pill R, French J, Harding K, Stott N. Invitation to attend a health check in a general practice setting: comparison of attenders and non-attenders. J R Coll Gen Pract 1988;38:53–6.
4. Jørgensen T, Borch-Johnsen K, Thomsen TF, Ibsen H, Glümer C, Pisinger C. A randomized non-pharmacological intervention study for prevention of ischaemic heart disease: baseline results Inter99. Eur J Cardiovasc Prev Rehabil 2003;10:377–86.
5. Wilhelmsen L, Berglund G, Elmfeldt D, Tibblin G, Wedel H, Pennert K, et al. The multifactor primary prevention trial in Göteborg, Sweden. Eur Heart J 1986;7:279–88.
6. Gøtzsche PC. Deadly medicines and organised crime: How big pharma has corrupted health care. London: Radcliffe Publishing 2013.
7. Nissen SE. Cardiovascular effects of diabetes drugs: emerging from the dark ages. Ann Intern Med 2012;157:671–2.
8. Ebrahim S, Taylor F, Ward K, Beswick A, Burke M, Smith GD. Multiple risk factor interventions for primary prevention of coronary heart disease. Cochrane Database Syst Rev 2011;1:CD001561.
9. Diao D, Wright JM, Cundiff DK, Gueyffier F. Pharmacotherapy for mild hypertension. Cochrane Database Syst Rev 2012;8:CD006742.
Rapid Response:
Re: Government prioritises health checks for 15 million adults despite pre-election promise to scrap them
In his assessment of the BMJ version of our Cochrane review on general health checks,(1) Michael Caley has confused the year of trial start with the year of publication, although we had stated this clearly in tables 1, 2, and 3, in the legends for the meta-analysis (figures 6, 7, and 8), and on page 4. The publication years for the mortality results are as follows: 1977, 1977, 1982, 1986, 1986, 1986, 1998, and 2005. For the OXCHECK trial (that ran from 1989 to 1993), we got unpublished mortality results from the authors. It is therefore wrong when Michael Caley claims that most studies reported results before 1971.
The assertion that our review does not indicate what happened during the health checks is also wrong. We dedicated a page-size table (table 3) to give an overview of the tests used, and table 1 describes other important features, e.g. where the health checks took place, whether a lifestyle intervention was included and the number of health checks offered. The corresponding Cochrane review gives even more detail on the health checks, such as the exact blood tests used and the type of lifestyle intervention.
We did not select trials on the basis of the type of follow-up used. Most trials did not specify which treatments were used and in some, participants with identified abnormalities were referred to their primary care physician for follow-up. However, this certainly cannot be interpreted as if a treatment was not given, as the trials were conducted in an era with a focus on treatment of risk factors (contrary to what Caley asserts). The statement that "no reference is made to any medical treatment being given", is also wrong, as we mentioned the possibility of bias (favouring the intervention) from trials using follow-up by specialists or by specific treatment algorithms ('Risk of bias', lines 16-20).
Michael Caley's optimism about health checks today is not only unwarranted, it is in direct conflict with the best available evidence. Although he is correct that several interventions for reducing cardiovascular risk have well-documented efficacy, it is not a given that these perform as well in the context of population-based health checks. An important feature of many of the trials we reviewed was their pragmatic design: no exclusion criteria, no run-in periods, and realistic follow-up, rather than the frequent monitoring seen in some drug trials, which may affect treatment compliance. Self-selection is a strong factor in health checks, and participants tend to have better risk profiles,(2) higher socio-economic status,(3) and lower morbidity(4) and mortality.(5) Thus, health checks tend to reach those who need them the least, reducing any benefits on a population level, while maintaining the harms, i.e. the inevitable overdiagnosis and overtreatment.
Another reason for trusting the trials we reviewed is that they had very little industry funding, in contrast to many drug trials. Given the high level of secrecy surrounding the industry's trial data, and given the abundant evidence of misrepresentation of research findings and even fraud in some industry trials,(6) it is possible that the balance between benefit and harm may be less favourable under real life conditions. Even worse, diabetes drugs were approved on the basis of surrogate outcomes for decades,(7) even though tolbutamide was shown to increase cardiovascular mortality compared to placebo or insulin, already in 1970.
Finally, we note that, although lifestyle interventions may impact positively on risk factors, they do not seem to have convincing effects on morbidity and mortality in general populations,(8) and while treatment of moderate or severe hypertension is beneficial, treatment of mild hypertension has not been shown to be so.(9)
Thus, there are plenty of possible explanations for the disappointing effects of health checks in the trials, and in the absence of evidence to the contrary, there is no reason to assume that the NHS Health Check is any better.
The large Inter99 trial of health checks and lifestyle intervention, with 10 years of follow-up, recently presented results, and they are in line with our results.
Lasse T Krogsbøll
Karsten Juhl Jørgensen
Peter C Gøtzsche
1. Krogsbøll LT, Jørgensen KJ, Grønhøj Larsen C, Gøtzsche PC. General health checks in adults for reducing morbidity and mortality from disease: Cochrane systematic review and meta-analysis. BMJ 2012;345:e7191.
2. Waller D, Agass M, Mant D, Coulter A, Fuller A, Jones L. Health checks in general practice: another example of inverse care? BMJ 1990;300:1115–8.
3. Pill R, French J, Harding K, Stott N. Invitation to attend a health check in a general practice setting: comparison of attenders and non-attenders. J R Coll Gen Pract 1988;38:53–6.
4. Jørgensen T, Borch-Johnsen K, Thomsen TF, Ibsen H, Glümer C, Pisinger C. A randomized non-pharmacological intervention study for prevention of ischaemic heart disease: baseline results Inter99. Eur J Cardiovasc Prev Rehabil 2003;10:377–86.
5. Wilhelmsen L, Berglund G, Elmfeldt D, Tibblin G, Wedel H, Pennert K, et al. The multifactor primary prevention trial in Göteborg, Sweden. Eur Heart J 1986;7:279–88.
6. Gøtzsche PC. Deadly medicines and organised crime: How big pharma has corrupted health care. London: Radcliffe Publishing 2013.
7. Nissen SE. Cardiovascular effects of diabetes drugs: emerging from the dark ages. Ann Intern Med 2012;157:671–2.
8. Ebrahim S, Taylor F, Ward K, Beswick A, Burke M, Smith GD. Multiple risk factor interventions for primary prevention of coronary heart disease. Cochrane Database Syst Rev 2011;1:CD001561.
9. Diao D, Wright JM, Cundiff DK, Gueyffier F. Pharmacotherapy for mild hypertension. Cochrane Database Syst Rev 2012;8:CD006742.
Competing interests: No competing interests