Evidence‑based cardiovascular risk assessment. Compute TC/HDL ratio, LDL/HDL ratio, Non‑HDL cholesterol, and interpret your lipid profile using updated clinical guidelines.
Contemporary cardiology emphasizes that TC/HDL ratio and LDL/HDL ratio are superior predictors of atherogenic risk compared to total cholesterol alone. The Framingham Heart Study, PROCAM, and multiple meta‑analyses confirm that a high TC/HDL ratio is strongly associated with coronary artery disease events. An optimal ratio (below 3.5) indicates a protective lipid metabolism, whereas values above 5.0 signify markedly elevated risk, often independent of LDL concentration.
TC/HDL ratio = Total Cholesterol ÷ HDL Cholesterol
LDL/HDL ratio = LDL Cholesterol ÷ HDL Cholesterol
Non‑HDL = Total Cholesterol − HDL (target <130 mg/dL)
LDL is either directly measured or estimated using the Friedewald equation:
LDL = TC − HDL − (TG/5) [valid for TG < 400 mg/dL].
Units compatibility: Ratios are dimensionless and identical in mg/dL or mmol/L. For Friedewald in mmol/L: LDL = TC − HDL − (TG/2.2). This tool assumes mg/dL; you may convert manually using: 1 mmol/L TC/HDL/LDL = 38.67 mg/dL; 1 mmol/L TG = 88.57 mg/dL.
Based on the National Cholesterol Education Program (NCEP ATP III) and European Society of Cardiology (ESC) guidelines:
| Ratio | Optimal | Borderline | High Risk | Very High Risk |
|---|---|---|---|---|
| TC/HDL (men – current tool standard) | <3.5 | 3.5–5.0 | 5.0–6.5 | >6.5 |
| TC/HDL (women – for awareness) | <3.2 | 3.2–4.5 | 4.5–5.8 | >5.8 |
| LDL/HDL | <2.0 | 2.0–3.0 | 3.0–4.0 | >4.0 |
| Non-HDL (mg/dL) | <130 | 130–159 | 160–189 | ≥190 |
Step 1: You provide Total Cholesterol, HDL, Triglycerides, and optionally direct LDL. The tool verifies valid numeric entries (positive values).
Step 2: If a direct LDL value is given, it is used directly. Otherwise, the Friedewald formula estimates LDL provided triglycerides are <400 mg/dL and positive. In cases where TG ≥400, a warning appears as the formula becomes unreliable; we still display computed estimate but advise clinical measurement.
Step 3: TC/HDL ratio = TC/HDL, and LDL/HDL ratio = LDL/HDL. Non‑HDL is computed as TC − HDL.
Step 4: Each ratio is matched against evidence-based cutoffs, and a personalized risk interpretation is generated.
Step 5: The dynamic gauge visualizes where your TC/HDL ratio lies relative to population risk thresholds.
A patient presents with TC=245 mg/dL, HDL=38 mg/dL, TG=210 mg/dL. Direct LDL unavailable. Using Friedewald: LDL ≈ 245 - 38 - (210/5) = 245 - 38 - 42 = 165 mg/dL. TC/HDL = 6.45 (very high risk), LDL/HDL = 4.34 (high). Non‑HDL = 207 mg/dL. This profile indicates aggressive lipid management, statin therapy, and lifestyle modification. The calculator instantly captures this and educates the patient about the urgency.