To establish a useful and simple model for evaluating biological age (BA) and to explore the clinical significance of this model.Methods
A waist circumference density index (WCDI) was established by considering the body as a cylinder and the waist circumference (WC) as the perimeter of this cylinder. Body volume was obtained from WC and height. Body density was obtained by dividing weight by volume, WCDI=weight (kg)÷[height (m)0.5×WC (m)2], thereby eliminating the impact of weight and height on WC. Waist circumference density age (WCDA), used to assess the clinical significance, was established as WCDA=chronological age−190+2.4×WCDI. WCDA was calculated for different groups of subjects, including healthy individuals and inpatients with primary hypertension or chronic obstructive pulmonary disease.Results
WCDI was related to chronological age. The average WCDA of healthy Chinese subjects was 35.63±23.77. The WCDA in patients with hypertension or COPD was significantly lower than that of the control group, evaluated using age-matched pairs of patients.Conclusions
WCDI may be an effective parameter for evaluating BA; WCDA may be a helpful indicator for evaluating some diseases.