Low serum cholesterol concentration and short term mortality from injuries in men and women

To determine whether total serum cholesterol concentration predicts mortality from injuries including suicide.

Cohort study of men and women who had their serum cholesterol concentration measured as part of a general health survey in Värmland, Sweden in 1964 or 1965 and were followed up for an average of 20.5 years.

Adults participating in health screening in 1964-5 (26,693 men and 27,692 women). The study sample was restricted to subjects aged 45-74 years during any of the 20.5 years of follow-up.

Serum cholesterol concentration. Deaths from all injuries and suicides during three periods of follow up (0-6 years, 7-13 years, and 14-21 years) according to the Swedish mortality register in subjects aged 45-74. Adjustment was made for prevalent cancer (identified from the Swedish cancer register) at the time of a suicide.

A strong negative relation between cholesterol concentration and mortality from injuries was found in men during the first seven years of follow up. The relative risk in the lowest 25% of the cholesterol distribution was 2.8 (95% confidence interval 1.52 to 4.96) compared with the top 25%. Most of the excess risk was caused by suicide with a corresponding relative risk of 4.2 (p for trend = 0.001). Correction for prevalent cancer did not change the results. Events occurring during the latter two thirds of the 20.5 years of follow up were not predicted. In women no relation between cholesterol concentration and mortality from injuries was found.

Together with observations from intervention trials the findings support the existence of a relation between serum cholesterol concentration and suicide. The causality of such a relation is, however, not resolved.