The association of low serum cholesterol with depression and suicidal behaviours: new hypotheses for the missing link.

Several observational studies indicate that reduction of serum cholesterol levels is related to an increase in violent deaths and suicide but the nature of this possible relationship remains unclear. Many confounding factors, e.g. poor health, depression and loss of appetite may play a role in the apparent relationship between serum cholesterol levels and suicide. Two separate phenomena should be considered: lowering total cholesterol and low total cholesterol. This review considers the evidence from epidemiological studies on serum cholesterol lowering and psychiatric disturbances. The available evidence does not seem to substantiate the view that large-scale intervention to reduce cholesterol concentrations could lead to more violent and aggressive behaviour, and generally greater unhappiness. In recent trials using statin treatment, there were slightly fewer deaths from accidents and suicide in the treated group compared with the placebo group. We believe that clinicians should not be deterred from prescribing cholesterol-lowering drugs, to reduce the risk of death from coronary heart disease, when they are indicated.