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Posted on Monday August 26, 2024 in Health Screening
A blog article Dr Edward Leatham Consultant Cardiologist
Cardiologists and preventative care physicians have been convinced for many years that serum cholesterol, or more accurately a high LDL cholesterol, is a major modifiable risk factor for coronary heart disease, acknowledging that in a minority of those affected by coronary heart disease, type 1 and 2 diabetes are also of major importance too. However there has been, in my view, scant attention to detecting and treating pre-diabetes and increased glucose variability (GV). Recent technology advances, along with a bunch of glucose modifying drugs, (including GLP-1 agonists and SGLT2 inhibitors), now licensed as clinically effective treatments for various heart conditions, are in part, why many cardiologists have become increasingly interested in glucose metabolism, a branch of medicine usually looked after by our endocrinology colleagues.
Continuous glucose monitors (CGMs) have emerged as a valuable tool for managing blood sugar levels and assessing real time blood glucose, and it’s variability, not just for individuals with diabetes, but also for non diabetics looking to prevent future health complications. There is accumulating scientific evidence that increased GV and intermittent blood glucose excursions above 7.8 mmol/L (140 mg/dL) are potentially just as important as sustained glucose highs found in diabetic patients. Large population studies have found GV to be as important a risk factor as HbA1C [1]. It is fascinating that people surviving to over 100 years of age, when compared to a less aged population, maintain a low average blood glucose level and keep blood glucose fluctuations in the normal range, suggesting that good glucose homeostasis may be conducive to longevity [2]. It is becoming increasingly clear that short-term fluctuations or ‘spikes‘ can contribute to inflammatory processes in the body that increase the risk of future illnesses such as coronary heart disease and dementia.
We do not fully understand what factors determine our individual responses to carbohydrate intake however it seems very likely to be a blend of genotype (heritable factors that cannot be altered) and lifestyle and food choices that COULD and probably SHOULD be modified, especially if an individual with unhealthy tissue glucose excursions on CGM has a high cardiovascular risk profile .
Given the growing body of research, here are five compelling reasons why individuals, especially those over the age of 20, should consider using a CGM to monitor their glucose levels.
Recent research indicates that individual responses to standard glucose loads can vary widely [3], and predicting these responses is challenging without testing. For families with a history of type 2 diabetes in particular, glucose spikes may indicate a predisposition, however it seems that a high proportion of people without a family history also ‘spike’ their glucose, which may be causing harm. This insight is important because discovering that you are prone to glucose spikes through CGM analysis—particularly if you have a family history of diabetes—allows you to take preventive measures.
‘Glucotype’ is a relatively new concept in non diabetics, born out of the data provided by CGMs. Although it lacks a formal definition by international agreement, we recognise a range of glucotypes based on CGM results over 1-2 weeks. At one end of the spectrum, there are individuals whose glucose levels remain within healthy limits (3.9 to 7.8 mmol/L) without any significant rapid excursions (‘spikes’ ) or values above 7.8 mmol/L in response to food intake. At the other extreme, there are those whose glucose levels move rapidly or ‘spike’ and often above 7.8 mmol/L multiple times each day, sometimes exceeding 10 mmol/L. In this latter group, we would also observe a large proportion also have a benchmark lab test HbA1c that is close to or within the WHO defined ‘pre diabetic’ range.
Identifying your glucotype can guide you in making dietary and lifestyle adjustments that can mitigate the risks associated with high glucose variability.
Since predicting glucotype is not feasible without testing, using a CGM can provide personalised insight. It can help patients understand whether they have a glucotype associated with higher risk of long-term conditions. While we cannot change our genetic code, understanding one’s glucotype empowers people to modify lifestyle and diet to align with the body’s unique needs, potentially preventing the onset of diabetes or other glucose-related conditions.
Obesity and increased Body Mass Index (BMI) are global concerns, exacerbated by modern sedentary lifestyles and high-caloric diets. Research shows that people with dysregulated glucose levels after consuming high-glycaemic foods are more likely to gain weight. CGMs can help identify these spikes, enabling individuals to adjust their diets to avoid or minimise foods that cause such excursions.
Many individuals have reported that by understanding their glucose responses and making targeted dietary changes, they have been able to lose weight more effectively. This aligns with concepts popularised by figures like Jessie Inchauspé (the ‘Glucose Goddess’) and in her best selling book ‘Glucose Revolution’, which suggest that avoiding glucose spikes can reduce the body’s conversion of excess glucose to adipose tissue (fat). In simpler terms, if you identify foods that cause glucose spikes and either eliminate them or change how you consume them (such as combining them with fibre or healthy fats), you may be able to eat sufficient food to satiate ie not feel hungry, without gaining weight and in many cases, actually lose body weight related to accumulation of central fat stores. This insight can be particularly transformative for those struggling with weight management.
Exercise is a well-known strategy for weight loss and overall health improvement. However, for individuals who experience glucose spikes, exercise alone may not be enough. It’s known that fat burning during exercise is less effective when glucose and insulin levels are high. For people who have glucose spikes after meals, exercising when glucose levels are elevated may therefore not lead to fat loss due to this insulin-related phenomenon.
Using a CGM can help you better understand how your body responds to food and exercise. If you notice that your glucose levels spike after meals, you might decide to incorporate physical activity shortly after eating to help moderate glucose levels. Conversely, if your goal is to burn fat, you may choose to exercise at times when your glucose levels are lower. By monitoring glucose in real-time, you can adjust your exercise regimen to optimise both glucose regulation and fat burning, making your workouts more effective.
A significant risk factor for developing type 2 diabetes later in life is having a family history of the disease or pre diabetes. Although current research does not conclusively prove that intervening on glucose spikes will prevent diabetes, our initial experience suggests that monitoring glucose levels and adjusting lifestyle accordingly may delay or prevent the onset of diabetes.
Individuals with slightly elevated HbA1c levels, indicative of pre-diabetes clearly have dysregulated glucose patterns on CGMs. By using this information to adjust diet and exercise, many report (and confirmed in the few that we have seen) they successfully lowered HbA1c levels back into the normal range, without medication. While large-scale clinical trials are still needed to validate such findings in a large cohort, existing evidence supports the idea that individuals can use CGMs to take proactive steps in managing their glucose levels, potentially preventing diabetes.
Perhaps the most compelling reason to use a CGM is the potential to prevent long-term inflammatory conditions, such as coronary heart disease and dementia. There is growing speculation that glucose dysregulation—occurring even in the absence of diabetes—may be a significant, yet unrecognised, risk factor for these conditions. It is plausible that glucose spikes that develop in your 20s could contribute to developing diseases that manifest decades later.
While we wait for large-scale trials to confirm these associations and for potential lifestyle and pharmacological interventions to be developed, CGMs offer a proactive approach. By monitoring glucose levels, individuals can make dietary and lifestyle changes that reduce glucose spikes and potentially lower the risk of long-term inflammatory conditions. This approach aligns with a preventive health model, allowing individuals to take action before formal guidelines or evidence are established.
Additionally, many patients report feeling better overall after stabilising their glucose levels. They experience improved sleep, fewer energy crashes, and, in some cases, weight loss. These immediate benefits provide additional motivation to monitor glucose levels and adjust behaviour accordingly.
For all these reasons, continuous glucose monitoring offers a valuable tool for anyone concerned with their long-term health, especially those with a family history of diabetes or other risk factors for cardiovascular diseases. Whether through self-monitoring or professional analysis such as our metabolic health assessment, CGMs can provide actionable insights that help individuals manage their glucose levels more effectively, ultimately contributing to a healthier, longer life. By understanding and managing your glucotype, optimising your diet and exercise, and taking steps to prevent prediabetes and diabetes, you can potentially avoid serious health conditions in the future.
For patients with coronary heart disease, raised coronary inflammation scores, CT evidence of early coronary disease, or weight issues, I generally recommend patients find out their Glucotype by undergoing continuous glucose monitoring. Whether you choose to purchase the equipment and interpret the results with guidance (see interpretation blog interpretation blog) or schedule our professional metabolic health assessment metabolic health assessment, CGMs could provide invaluable insights to support your long-term health and well-being.
Further reading
The idea of predicting a heart attack may have once seemed like science fiction, but it is rapidly becoming a reality. With the advent of advanced imaging techniques and artificial intelligence, we are now able to detect the early signs of coronary heart disease and intervene before a heart attack occurs. This represents a major shift in the way we approach cardiovascular care, moving from a reactive model to a proactive one.
Is is increasingly obvious that not everyone with raised coronary inflammation and elevated risk of heart attack simply has a raised LDL Cholesterol- in fact there appears to be a mixed bag of risk factors associated with high coronary artery inflammation, including raised LDL, raised LP (a), raised Homocysteine, hypertension and dysregulated glucose. Our metabolic health assessment is therefore designed to offer a comprehensive dive into known contributory causes, the latest and most controversial of which is 'glucose dysregulation', the principle topic of this article.
For patients who have been diagnosed with an acute coronary syndrome, requiring bypass surgery or stent, or have CT Angiography and or raised FAI.
Ultimately, the approach to cardiac CT screening is highly individualized, reflecting the diverse presentations and risk factors among patients. By employing a sophisticated pre-consultation process, cardiologists can tailor their assessment and management plans to best suit each patient's unique needs, enhancing the precision and effectiveness of cardiac care.
There are two main reasons left atrial thrombus forms then detaches to cause embolic stroke. The first is that during atrial fibrillation or flutter, a thrombus may develop in the left atrial appendage, which does not move as much as it does when in sinus rhythm. The likelihood of this occurring in any given year is low, correlated to the CHA2DS2-VASc score. The second reason is not related to CHA2DS2-VASc score
A new high quality MRI scanning service launched today by VCL and available at SCVC.
While aiming for the lowest possible blood pressure without experiencing adverse effects, individuals can explore a range of non-pharmacological strategies to maintain or improve their cardiovascular health. Personalised experiments, supported by accurate home monitoring, can lead to significant insights and potentially delay or reduce the need for medication, contributing to a healthier, longer life.
Written by Dr Edward Leatham, Consultant Cardiologist: Our patients benefit from team-based care. If they have an enquiry that cannot be immediately answered by the consultant or their PA (out of hours or due to annual leave), then other members of the team, including our specialist nurse practitioners, senior nurses, and technicians, may be able to help.