Chronic kidney disease: the canary in the coal mine

Life in primary care in 2023 is tough: there are workforce shortages (Deakin, 2022), an increased number of consultations (British Medical Association, 2022) and, perhaps the most challenging, a massive backlog of routine care (Oliver, 2022).

One thing the pandemic has reminded us of is that healthcare needs are far from uniform. Some people or communities are at greater risk of harm than others (Williamson et al, 2020). With limited resources, in a publicly-funded healthcare service, we need to focus our efforts on patients who are at the highest risk of harm. Cost-effective tests need to be used that can identify people at risk of poor and expensive outcomes.

The ‘canary in the coal mine’ is a term that comes from the old mining practice of using caged canary birds, who are extremely sensitive to carbon monoxide, to warn the miners of the impending danger of rising levels of that gas. Chronic kidney disease (CKD) can be seen as a similar early warning sign that all is not well in the cardiovascular system of the person being treated. CKD is a common condition, affecting 5% of people aged 75 and over, similar in prevalence to other conditions, such as diabetes (NHS Digital, 2016). It is defined by abnormalities of kidney structure or function, persistent for more than 3 months, with implications to health (KDIGO, 2013). The financial cost, based on data already acquired over 10 years ago, is £1.45 billion (Kerr et al, 2012). Most of these costs are for renal replacement therapy, such as dialysis. The rate of dialysis continues to increase year on year (UK Renal Registry, 2021) and so this condition is financially expensive. The quality of life for a person living with CKD is massively reduced (Nguyen et al, 2018) and mortality is also increased. The most common cause of CKD in the UK is diabetes. The combination of developing CKD with diabetes is associated with up to a 16 year decrease in life expectancy (Wen et al, 2017). There is a close association between advancing CKD and increased hospital admission, particularly from cardiovascular causes, such as heart failure (Kalantar-Zadeh et al, 2021). Cardiovascular disease remains the leading cause of mortality in people with CKD (National Institute of Health and Care Excellence (NICE), 2021a), with approximately 10% of people with CKD surviving to renal replacement therapy (United States Renal Data System (USRDS), 2020).