Monday 20 October 2014

Reviewing the evidence base for NHS Health Checks

The debate as to whether NHS Health Checks represent value for money was given renewed impetus towards the end of 2014 when two new studies into the programme were published in the Journal of Public Health and the British Journal of General Practice

The first of these—a cohort study by Forster et al published in October 2014 in the Journal of Public Health—used a significant sample of patient data (65,324 men and 75,032 women) ‘to estimate the yield of NHS Health Checks’ and assess the programme’s impact. The conclusions of this large-scale study were that the ‘universal prevention programme identifies substantial risk factor burden in a population without known cardiovascular disease’. In other words, NHS Health Checks are effectively revealing CVD risk factors in a large proportion of the 40-74 year old population that were previously presumed to be healthy.

Despite the weight of these findings, those calling for the programme to be abandoned appear to have paid little attention to them. The same however cannot be said for the amount of attention that critics gave to a recent study by Caley et al—published in August 2014 in the British Journal of General Practice—which claimed to assess ‘the impact of NHS Health Checks on the prevalence of disease in general practice’. The authors of this study assert that in 38 GP practices providing NHS Health Checks, the change in reported disease prevalence did not differ from 41 practices that did not provide the checks.

Whilst the programme’s detractors have cited this as evidence that the health checks should be scrapped, a number of researchers and clinicians have since pointed out that Caley et al’s study was, in fact, ‘not powered to support this conclusion’. In addition to there being concerns over the methodology and conclusions, further questions have been raised as to whether those calling for the national programme to be abandoned are basing their arguments on evidence that doesn’t accurately reflect the reality of what’s happening on the ground.

As Dr Matt Kearney—GP and National Clinical Advisor to Public Health England and NHS England—and others have identified, the study was ‘not randomised’, which may explain why it was underpowered to show an increase in disease prevalence. Perhaps more problematic however is that fact that researchers formed conclusions after having considered conditions that are not routinely included in the NHS Health Check.

Despite the authors examining the prevalence of 'hypertension, coronary heart disease (CHD), chronic kidney disease (CKD), atrial fibrillation (AF), and diabetes', as Dr Kearney and others note, CHD and AF are not assessed in the national programme. Although in the longer term you would expect CHD to fall if the health checks proved effective, this would take longer than the three year time frame that the study was confined to. 

This highlights a particular recurring issue in the debate; calls to abandon the health checks have often relied on research that doesn’t relate to the current model put forward by Public Health England (PHE). This was similarly found to be the case with the 2012 Cochrane Review, the conclusions of which the Department of Health say have 'little if any relevance to the NHS Health Checks'. There are a number of reasons for this, one of which was that most of the trials considered were out of date, some from as long ago as the 1960s.

Whilst a number in the health sector have identified Caley et al’s most recently published non-randomised study as lacking the evidence to justify its conclusions, rigorous randomised controlled trials into the NHS Health Check programme do exist. One such study monitored population changes in CVD risk factors over the first year of a new NHS Health Check service. This study – which is available in the Cochrane Library – concluded that the programme resulted in a 'significant reduction in estimated population CVD risk'.

The study also established that NHS Health Check programmes that incorporate Motivational Interviewing and ongoing tailored lifestyle support can 'significantly reduce the prevalence of central obesity'. Given that the UK was recently found to be among the worst in western Europe for the level of overweight and obese people, this insight into the value of high quality consultations is particularly timely. As the evidence suggests, the programme currently promoted by PHE – which is fundamentally conceived of as a supportive and motivational lifestyle intervention – will represent an important component in tackling the nation’s obesity problem, amongst other conditions.

For any public health agenda that takes seriously the notion of patient-centeredness, an essential consideration must clearly be the perspectives of patients themselves. As Janet Krska et al found from carrying out a study that investigated patients' views and experiences of the NHS Health Check, 'both attenders and non-attenders had positive views towards NHS Health Checks in general practice and resultant self-reported lifestyle change in attenders was high'. For this to be the case however, 'clear written information and explanation of personal CVD risk are required'. In other words, the quality of the consultation and support should be noted as repeatedly surfacing as the key to coordinating a successful programme. 

Whilst a number of the aforementioned studies firmly support the value of conducting NHS Health Checks, a nation-wide evaluation is yet to be completed. A forthcoming study by Imperial College London however will address specifically that issue by evaluating whether the national programme 'reduces the burden of heart disease and stroke and other vascular diseases while reducing inequalities in them'. In addition, researchers are investigating the effect of providers delivering patient-focussed health checks that 'extend beyond ticking the contractual boxes'. As has been emphasised in this article, (and as many in the sector would affirm), assessing the quality of health checks must be a fundamental consideration for any meaningful evaluation. 
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