Researchers already know that high cholesterol levels are a big risk factor for heart disease and that heart disease is a serious risk factor for depression in the elderly. A study from French researchers now shows new links between cholesterol levels and depression later in life; it also shows there are gender differences and genetic factors that haven’t been taken into account in previous studies.
Researchers followed nearly 1,800 men and women 65 years of age and older, beginning with an assessment of participants’ cholesterol levels and related genotypes. This study enhances a number of previously published related studies by proving that sex differences and genetic susceptibility play major roles in the relationship between cholesterol levels and depression in men and women over 65.
Total cholesterol is comprised of both”bad” cholesterol (LDL) and “good” cholesterol (HDL). Among male study participants, low levels of bad cholesterol were significantly associated with an increased risk of depression. In women, an increased risk of depression was seen with a low level of good cholesterol. Furthermore, female participants who had no history of stroke or heart attack were at even higher risk for depression than those with a history of such health issues.
Of five genes linked to depression, two are associated with cholesterol and strongly determine the development of major depression. Furthermore, the researchers found that for men, in addition to the risks associated with high cholesterol levels, they may be more vulnerable to developing depression based on the makeup of their genes.
For women, depression later in life was most strongly linked with high total cholesterol, high LDL-cholesterol, low HDL-cholesterol and high triglycerides. Having a low level of the “good” HDL-cholesterol is a major risk factor for vascular disease and women are especially vulnerable to these effects.
Essentially, the researchers discovered that cholesterol profiles are major factors in the development of depression in elderly women, while, for elderly men, their genetic vulnerability is the major factor. A clearer definition of “normal” lipid levels is also important. While physicians and nutritionists recommend that those over 65 years of age meet the lower threshold for LDL-cholesterol, male study participants with especially low levels of LDL-cholesterol had double the risk of developing depression, and the risk was six-fold if these men had high genetic vulnerability.
These results raise important questions related to depression. Can high cholesterol management help decrease the incidence and prevalence of depression in the elderly? Should physicians use different strategies to deal with depression in elderly men and women, given the gender differences found in this new research? Further research will be necessary to find answers, but it gives us one more reason to eat right and watch our cholesterol carefully.