Waist Circumference
A measurement around the abdomen used as a proxy for visceral fat and central obesity. Elevated waist circumference (>102cm men, >88cm women) is a diagnostic criterion for metabolic syndrome. Waist circumference reduction is a common secondary endpoint in weight management trials.
Technical Context
Measurement technique: measured at the midpoint between the lowest palpable rib and the iliac crest, at the end of normal expiration, using a non-elastic tape. Risk thresholds (ATP III/IDF): elevated risk >94cm men / >80cm women (European); substantially increased risk >102cm / >88cm. Ethnic-specific thresholds exist: South Asian/Chinese: >90cm men / >80cm women. Waist circumference correlates with VAT area (r ≈ 0.80) and is the simplest clinical proxy for visceral adiposity. GLP-1 RA trials typically report waist circumference as a secondary endpoint: semaglutide 2.4mg reduces waist circumference by approximately 13-14cm (STEP 1), reflecting preferential visceral fat loss. Waist-to-height ratio (<0.5 is generally healthy) is an alternative metric that may be more universally applicable across populations.