Changes in serum cholesterol in employees after three years of multifactorial intervention

To assess long-term effectiveness of a multifactorial intervention at the work-site on serum cholesterol levels.Individualized face-to-face counseling was given to 1,555 employees (76.7% male; mean age = 42.3 years) by occupational physicians at four work-sites. After 3 years, a blinded assessment of the adequacy of the intervention was done. Implementation of the intended intervention by physicians was assessed as adequate in two work-sites (927 employees) and inadequate in the other two (628 employees). Observed changes in serum cholesterol were analyzed in the followed-up individuals. Follow-up rates at each work-site were 78.6% and 44.5% for the adequate intervention, and 85.5% and 60.4% for the inadequate intervention. Changes in serum cholesterol were controlled for potential confounding factors (pre-test levels of risk factors, age, sex, body mass index, educational level, marital status, physical activity and alcohol consumption) by multiple linear regression procedures.When the intervention was adequately performed, serum cholesterol was significantly lowered with a mean reduction of 14.3 mg/dl (95% C.I.: 11.0 to 17.6) in those employees with baseline levelsor = 200 mg/dl.Adequacy of implementation of work-site programs determines their long-term effectiveness in reducing mean serum cholesterol levels.