Cardiometabolic Index (CMI)
The cardiometabolic index combines the waist-to-height ratio with the ratio of triglycerides to HDL cholesterol, giving one number that reflects both abdominal fat and an unhealthy blood-fat pattern.
Plain English
Patient-Friendly Explanation
The cardiometabolic index is a single number worked out from three ordinary measurements. First, the waist is measured and divided by height to give the waist-to-height ratio. Second, a blood test gives triglycerides and HDL cholesterol, and the triglyceride figure is divided by the HDL figure. The two results are then multiplied together. The idea, published in 2015, is that neither abdominal fat nor a poor blood-fat pattern tells the whole story on its own, so the index puts them together. A higher number means more fat around the internal organs plus a more unfavourable cholesterol pattern, and both of those travel with insulin resistance and raised long-term cardiovascular risk. In studies of adults, the index has separated people with fatty liver disease from those without it with good accuracy, and in women with severe obesity it identified metabolic syndrome more reliably than several older measures. It uses information that a weight clinic already collects, so it can be calculated at a consultation without any extra test and tracked over time. It is a summary of risk, not a diagnosis, and it is read alongside blood pressure, blood sugar and the rest of the assessment rather than on its own.
Medical
Clinical Definition
The cardiometabolic index (CMI) was proposed by Wakabayashi and Daimon as a composite marker of visceral adiposity and dyslipidaemia: CMI = waist-to-height ratio x (triglycerides / HDL cholesterol). The waist-to-height ratio supplies a measure of central fat distribution while the triglyceride-to-HDL ratio supplies a surrogate for insulin resistance and small dense LDL particles, so a single unitless value captures both dimensions of cardiometabolic risk. In a Chinese adult cohort the optimal CMI cut-offs for metabolic dysfunction-associated fatty liver disease were 0.6085 in men and 0.4319 in women, with an accuracy of 85.5%, a sensitivity of 87.5% and a specificity of 80% against MRI confirmation. In women with severe obesity, CMI reached an area under the curve of 0.86 for metabolic syndrome with a cut-off above 0.84, marginally ahead of the visceral adiposity index at 0.84. An NHANES analysis of hypertension found a non-linear relationship with a threshold near 2.64 and an odds ratio of 1.32 per unit below that threshold. The index requires only a tape measure and a standard lipid profile, but the lipid component means it should not be used to judge progress during acute illness or in people taking lipid-lowering therapy, since treatment alters the ratio independently of fat mass.
Key Insight
Why It Matters
Weight clinics already measure waist and lipids; the cardiometabolic index simply combines them so that change in both is visible in one number. It is a useful tracking measure for patients whose weight is falling slowly while their metabolic profile is improving, and it flags people whose waist and blood fats suggest visceral fat even when body mass index looks acceptable. It is a risk summary, not a substitute for blood pressure, glycaemic assessment or a liver ultrasound.
Sources
Reviewed against standard medical references.
Medically reviewed by
Family Physician & Registered Acupuncturist, Accord Medical Clinic. MBBS (NUS), Graduate Diploma in Family Medicine (NUS), Graduate Diploma in Acupuncture (Singapore College of TCM).
Last reviewed: October 2026
This page is general health education, not medical advice. Whether any treatment is appropriate for you is a decision made in consultation after assessment.
