Source: Krogsboll LT, Jorgensen KJ, Larsen CG, and Gotzsche PC. General health checks in adults for reducing morbidity and mortality from disease. Cochrane Database of Systematic Reviews 2012, Issue 10. Art. No.: CD009009.
Efficacy Endpoints: Total mortality, cardiovascular mortality, cancer mortality; additional group of secondary outcomes
Harm Endpoints: Not addressed
Narrative: Benjamin Franklin reportedly said, “An ounce of prevention is worth a pound of cure.” Many health authorities have embraced preventive care, and in the United States the Affordable Care Act has mandated and incentivized a number of screening examinations. Although some have proven useful, prior to this review a comprehensive appraisal of general health checks, i.e. annual check-ups, had not been performed.
This Cochrane Collaboration review compared health checks, defined as “screening general populations for more than one disease or risk factor in more than one organ system,” to no health checks in a general, non-geriatric adult population. The authors included 14 trials of 182,880 subjects, testing three outcomes primarily: overall mortality, cardiovascular mortality, and cancer-related mortality.
Nine trials found no difference in overall mortality (7.4% in the intervention group and 7.5% in the control groups) with no observed heterogeneity across studies. Subgroups included less than or greater than five year follow up, old versus recent trials, USA versus European cohorts, and others, with no differences noted.
Health checks also failed to improve cardiovascular-specific mortality in eight trials, at 3.8% in the intervention group and 3.7% in the control group, though heterogeneity for this comparison was substantial. This was attributed to varying definitions of cardiovascular disease (myocardial infarction, stroke, etc).
For cancer-specific mortality rates were 2.1% in both intervention and control groups with moderate heterogeneity.
For secondary outcomes no difference was found in morbidity, hospitalizations, disability, physician visits, specialist referrals, absence from work, or patient worry, however there was a slight increased sense of self-health among those assigned to checkups. There were also increases in new diagnoses such as hypertension and hyperlipidemia, in self-reported chronic disease, and in use of medication such as antihypertensives.
Caveats: Overall, this is a powerful review. Moreover, the primary outcomes of (overall and disease-specific mortality) and many of the secondary outcomes were patient-oriented and clinically important.
A previous review1 including both observational studies and trials found increased testing in those undergoing check-ups, and classified this as a benefit. The review summarized here is the only large-scale meta-analysis of randomized-controlled trials of which we are aware, and the only one to focus on patient-oriented outcomes.
The studies in this review assessed check-ups in a general population, and it is possible, and in fact likely, that a higher risk population would obtain greater benefit. A prior review 2 for instance examined trials with exclusively hypertensive or diabetic subjects, and demonstrated significant reductions in mortality. Screening populations, unlike higher-risk groups, are typically healthy at baseline. The purpose of health checks as screening is to ostensibly detect incipient problems like diabetes and hypertension, rather than to perform interventions directed at improving health.
Importantly, the authors excluded geriatric studies because these routinely used interventions directed at improving quality of life and independence, rather than screening. A prior geriatric review showed that such interventions could reduce nursing-home admissions, hospital admissions, and falls 3.
Of note, the majority of included studies dated to the 1960s and 70s; the WHO trial of 56,560 individuals from 1971 represented a large proportion of subjects in the metaanalysis.
Regarding bias, most studies were effectively randomized with good allocation concealment, though the inherent difficulty in blinding to health screening as an intervention may have resulted in differential treatment. There was also missing data largely in the secondary, subjective outcome measures.
While the authors report on well-studied benefits, less robust data was available regarding harms of screening, including unnecessary follow-up procedures, surgery, anxiety, cost, and loss of insurance from additional diagnoses.
Author: Gary Green, MD
Published/Updated: May 12, 2014
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