What is the evidence behind guideline recommendations to monitor chronic diseases in UK primary care?

Background More than half of tests ordered by GP practices are to monitor long-term conditions such as high blood pressure, diabetes, and chronic kidney disease (CKD). There is a large variation in ordered tests between GP practices, suggesting some tests may not be appropriate. Unnecessary testing should be avoided as it can generate anxiety for patients, increase workload for doctors, and increase costs for the health service.
Aim The objective was to review monitoring strategies for hypertension, type 2 diabetes, and CKD patients and to investigate the evidence-base underlying these recommendations.
Method Current UK guidelines on the relevant diseases were reviewed. Any guidance on the use of laboratory tests for disease monitoring (not including drug monitoring recommendations), the recommended frequency of testing, as well as the level of evidence on which the guidance was based was extracted.
Results Guidelines for the use of monitoring tests in primary care for hypertension, diabetes, and CKD are unclear and incomplete; for example, recommended frequency of testing varied between guidelines or was not specified at all. Current recommendations for monitoring chronic diseases are largely based on expert opinion; robust evidence for optimal monitoring strategies and testing intervals is lacking.
Conclusion In the absence of clear evidence, clinicians should consider which tests are likely to influence patient management and should ensure that there is a clear clinical rationale for each test that they perform. Future research should address what the optimal strategy for monitoring chronic conditions consists of, and how it can be evaluated.