The most dangerous characteristic of the diseases that cause the majority of preventable deaths in the UK is not their severity at the point of diagnosis but their silence in the decades preceding it. Atherosclerosis, the gradual accumulation of atherogenic plaques in arterial walls that ultimately produces heart attacks and strokes, typically takes 20 to 30 years to develop from its earliest endothelial changes to the clinical events that announce its presence. Type 2 diabetes is preceded by a decade or more of progressive insulin resistance and pancreatic beta-cell dysfunction before fasting glucose reaches diagnostic thresholds. Early-stage cancers may produce no symptoms for years while the biology is still relatively amenable to intervention. The window for prevention, the period during which these processes can be interrupted or reversed through lifestyle and targeted intervention, is open for decades before the clinical disease becomes apparent. Biomarker testing allows us to know whether that window is open and how urgently action is needed, rather than waiting for the symptom or event that announces the window has closed.
Cardiovascular Disease: The Biomarkers Beyond Standard Cholesterol
Standard cholesterol panels measure total cholesterol, HDL cholesterol, LDL cholesterol, and triglycerides. These are useful measures but they fail to capture important information about cardiovascular risk. Apolipoprotein B is the protein component of all atherogenic lipoproteins including LDL, VLDL, and IDL, and each atherogenic particle carries exactly one ApoB molecule. ApoB measurement therefore directly counts the number of atherogenic particles in the blood, which is mechanistically the most relevant cardiovascular risk marker because it is the particle that penetrates the arterial intima and initiates plaque formation, not the absolute amount of cholesterol carried. Multiple large prospective studies have confirmed that ApoB is a stronger predictor of cardiovascular events than LDL cholesterol, particularly in individuals with high triglycerides or small, dense LDL particles where LDL cholesterol concentrations may substantially underestimate particle number.
Lipoprotein(a), usually abbreviated as Lp(a), is a genetically determined lipoprotein with independent atherogenic and thrombogenic properties that is elevated in approximately 20 percent of the general population. It is not measured in standard cholesterol panels, is not modified by statins, and is responsible for a significant proportion of cardiovascular events in people who appear to be at low risk by conventional cholesterol assessment. Testing for Lp(a) is a once-in-a-lifetime measurement, because the levels are largely genetically determined and do not change significantly with lifestyle, but knowing it allows appropriate management of overall cardiovascular risk, including the initiation of more aggressive lifestyle and statin therapy in those who carry the elevated Lp(a) burden. High-sensitivity CRP is an inflammatory marker that independently predicts cardiovascular events beyond its value as a general inflammatory indicator, reflecting the chronic vascular inflammation that drives plaque progression.
Metabolic Health: Detecting Insulin Resistance Years Early
Fasting glucose becomes abnormal only when insulin resistance is already advanced and the pancreatic beta cells are failing to compensate adequately for the reduced insulin sensitivity of peripheral tissues. The earlier marker is fasting insulin: a person whose fasting glucose is entirely normal but whose fasting insulin is elevated is producing significantly more insulin than expected to maintain that normal glucose, indicating that their tissues are already insulin resistant and the pancreas is working harder to compensate. HOMA-IR, calculated from the ratio of fasting insulin to fasting glucose, provides a validated quantitative measure of insulin resistance that identifies metabolic dysfunction years before fasting glucose or HbA1c become abnormal.
Triglycerides and the triglyceride-to-HDL ratio provide additional metabolic health information at minimal additional cost. Elevated fasting triglycerides in combination with low HDL and a modestly elevated waist circumference form the core of the metabolic syndrome definition and are indicative of atherogenic dyslipidaemia driven by insulin resistance. Uric acid, a metabolic byproduct of purine metabolism that is elevated by fructose overconsumption and alcohol, is an emerging cardiovascular risk marker and is also elevated in insulin resistance. The combination of fasting insulin, HOMA-IR, triglycerides, and uric acid provides a metabolic health profile that identifies insulin resistance in its early, reversible stages rather than waiting for overt diabetes.
Inflammatory and Hormonal Biomarkers
Chronic low-grade inflammation is a driver of cardiovascular disease, cancer, neurodegenerative disease, and accelerated biological ageing. High-sensitivity CRP is the most commonly measured inflammatory marker, with values above 3 mg/L associated with significantly elevated cardiovascular risk independent of cholesterol levels. IL-6 and TNF-alpha, pro-inflammatory cytokines from adipose tissue and immune cells, contribute to the inflammatory burden of obesity and sarcopenia. Homocysteine, an amino acid metabolite elevated by deficiencies in vitamins B6, B12, and folate, is independently associated with cardiovascular disease, cognitive decline, and fracture risk. Vitamin D is a steroid hormone with roles in immune function, bone metabolism, muscle function, cardiovascular health, and cancer prevention whose deficiency is extremely common in the UK and on the Isle of Man given limited sunlight.
Sex hormone testing is relevant to the Longevity MOT particularly for those over 40, because declining testosterone in men and declining oestrogen in women both directly affect muscle mass, bone density, cardiovascular risk, cognitive function, and metabolic health in ways that can be partially addressed through lifestyle, nutrition, and in some cases appropriately prescribed hormone therapy. Thyroid function, specifically TSH and free T4, deserves inclusion because subclinical hypothyroidism is common, particularly in women over 50, and produces fatigue, weight gain, elevated cholesterol, and cognitive slowing that are frequently misattributed to normal ageing or stress.
Functional Biomarkers: Measuring What Your Body Can Do
Beyond blood-based biomarkers, functional measures provide equally powerful longevity predictions. Cardiorespiratory fitness measured as VO2max or estimated from standardised exercise tests is the single most powerful predictor of all-cause mortality identified in the literature. Myers and colleagues published a landmark study in the New England Journal of Medicine in 2002 finding that exercise capacity was a stronger predictor of mortality than any other established risk factor including hypertension, smoking, and diabetes, with each metabolic equivalent increase in exercise capacity associated with a 12 percent reduction in mortality risk.
Handgrip strength, gait speed, and the five-times sit-to-stand test are functional measures that independently predict falls, hospitalisation, and mortality in prospective cohort studies. The PURE study grip strength data, discussed in the sarcopenia section of this article series, confirmed that grip strength predicted cardiovascular mortality more strongly than systolic blood pressure. Cognitive function assessed through validated brief neuropsychological tests provides an early indication of cognitive reserve and any early changes that might indicate prodromal neurodegenerative disease, while measures are still in the range where lifestyle intervention can most meaningfully preserve function. The full Longevity MOT at Zhen Wellness on the Isle of Man encompasses all of these domains in a single assessment.
- ApoB counts atherogenic particles directly; it outperforms LDL cholesterol as a cardiovascular predictor
- Lp(a) is elevated in 20% of people, is not measured in standard panels, is not modified by statins, and must be known
- HOMA-IR identifies insulin resistance years before fasting glucose becomes abnormal
- High-sensitivity CRP above 3 mg/L independently elevates cardiovascular risk beyond cholesterol levels
- VO2max is the most powerful predictor of all-cause mortality available; each MET increase reduces mortality risk by 12%
- Grip strength predicts cardiovascular mortality more strongly than systolic blood pressure (PURE study)
- Homocysteine, vitamin D, thyroid function, and sex hormones complete the biomarker picture for longevity
Sources
- Kokkinos, P., et al. (2022). Cardiorespiratory fitness and mortality risk across the spectra of age, race, and sex. JAMA Network Open, 5(5), e2218174.
- Myers, J., et al. (2002). Exercise capacity and mortality among men referred for exercise testing. New England Journal of Medicine, 346(11), 793-801.
- Leong, D.P., et al. (2015). Prognostic value of grip strength: findings from the PURE study. Lancet, 386(9990), 266-273.
- Benn, M., et al. (2019). Apolipoprotein B levels, APOB alleles, and risk of ischemic cardiovascular disease. Atherosclerosis, 282, 174-183.
- Ridker, P.M., et al. (2005). C-reactive protein and the prevention of cardiovascular disease. New England Journal of Medicine, 352(1), 20-28.