Simplified methods to estimate lean body mass (LBM), an important nutritional measure representing muscle mass and somatic protein, are lacking in non-dialyzed patients with chronic kidney disease (CKD).

Objective: We developed and tested a reliable equations for estimation of LBM in daily clinical practice.

Two cross-sectional data sets were derived from outpatients with CKD stage 3-5 in Peking University First Hospital.Two equations for estimating LBM based on midarm muscle circumference (MAMC) or hand grip strength (HGS)were developed and validated in CKD patients with dual-energy x-ray absorptiometry (DEXA) as referenced gold method. Demographic data, comorbidity, and other clinical variables were also recorded.

Inclusion Criteria:

• non-dialyzed patients with CKD stage 3-5
• clinical stable
• a willingness to be examined with all measurements being taken simultaneously.

Exclusion Criteria:

• systemic infections, acute cardiovascular events, operations, trauma, active hepatitis or tumor
• severe edema within one month prior to the study
• chronic infections, connective tissue disease, hyper- or hypothyroidism, amputations or pregnancy,
• taking immunosuppressive agents and anti-inflammatory medication chronically

The development and validation groups both included 150 non-dialyzed patients with CKD stage 3-5.