The relationship of erythrocyte sodium-lithium countertransport to blood pressure and metabolic abnormalities in a sample of untreated middle-aged male workers.

Objectives: To investigate the relationship between erythrocyte sodium-lithium countertransport and blood pressure in a randomly selected sample of untreated male workers and to evaluate the influence of a set of metabolic abnormalities commonly associated with hypertension on this relationship.

Design: A cross-sectional investigation of a randomly selected sample of untreated male workers (n = 216, age range 21-59 years) at the Olivetti factory in Pozzuoli, Naples.

Methods: Standardized measurements of anthropometric and metabolic parameters, blood pressure and Na(+)-Li+ countertransport were performed.