- High levels of blood plasma lipoprotein are strongly associated with an increased risk of cardiovascular disease (CVD).
- Some types of plasma lipoprotein can be reduced through diet and exercise, but others, such as lipoprotein(a) are influenced by genetics.
- A new study has found that high lipoprotein(a) increases the 30-year risk of CVD, even in healthy women.
- The researchers suggest introducing routine screening to detect high lipoprotein(a).
According to the
High total blood plasma cholesterol, particularly low-density lipoprotein (‘bad’ cholesterol, or LDL-C), increases a person’s risk of CVD. High-density lipoprotein, or ‘good’ cholesterol, can reduce the risk of CVD. Levels of these types of cholesterol can be managed through following a healthy diet, increasing physical activity, not smoking, and, if needed, medications such as
However, one type of lipoprotein — Lp(a) — is largely genetically determined, so diet and lifestyle have little effect on levels of Lp(a). A study has found that high levels of this lipoprotein increase the 30-year risk of CVD, even in otherwise Healthy women.
The study, led by researchers at Brigham and Women’s Hospital in Boston, and published in
Lead author Ask T. Nordestgaard, MD, PhD, Postdoctoral research fellow, Division of Preventive Medicine, Brigham and Women’s Hospital, Boston, MA, told Medical News Today:
“I believe our findings a very important, since they really show how strong a predictor of long-term CVD risk elevated Lp(a) levels are even among healthy women.”
“Our findings highlight the importance of screening for elevated Lp(a) levels among Healthy individuals. Most importantly, so that we can initiate primary preventive measures among those with very extreme elevations.”
This study analyzed data from the Women’s Health Study, which was established in 1993 to investigate the benefits of low dose aspirin and vitamin E in preventing cardiovascular disease and cancer in women without pre-existing health conditions. A total of 39,876 women were enrolled in the study, and many still complete annual health questionnaires.
The researchers measured plasma Lp(a) in all baseline samples from 27,748 healthy women, then grouped the women from low to high levels of Lp(a).
- less than 10 mg/dL
- 10 to less than 30 mg/dL
- 30 to less than 60 mg/dL
- 60 to less than 90 mg/dL
- 90 to less than 120 mg/dL
- above or equal to 120 mg/dL.
They followed up the entire cohort for almost 30 years, recording incidence of CVD and any major cardiovascular events, such as heart attacks (myocardial infarctions),
During follow-up (median 27.8 years), the researchers recorded 3707 incident major cardiovascular events, 1985 coronary events, 1041 ischemic stroke events, and 1543 cardiovascular deaths in the total group.
Above 30mg/dL of Lp(a), the risk of major cardiovascular events and coronary heart disease increased. Below this level, there was no increase in risk.
Risk of ischemic stroke and death from cardiovascular causes increased only in those with extremely elevated Lp(a) of over 120mg/dL.
“Risk of CVD appeared to increase from above approximately 30 mg/dL. […] Those with very extreme Lp(a) levels have an almost 10% higher absolute risk of developing CVD across 30-years of follow-up.”
— Ask T. Nordestgaard, lead author
Researchers also found that women of European ancestry who carried a gene that increases Lp(a) had an increased risk of cardiovascular events.
Jennifer Wong, MD, board certified cardiologist and medical director of Non-Invasive Cardiology at MemorialCare Heart and Vascular Institute at Orange Coast Medical Center in Fountain Valley, CA, who was not involved in the study, commented:
“Lipoprotein [a] elevations are felt to be an independent predictor of cardiovascular disease. It may be interesting to see if there is an additive effect with other lipid abnormalities.”
Although Lp(a) levels are largely genetically determined, so lifestyle changes are unlikely to have much effect, Nordestgaard explained how people might reduce their overall CVD risk:
“Lp(a) levels are related to LDL cholesterol levels, mainly because Lp(a) particles contain cholesterol that is included in the total ‘LDL cholesterol’ calculation. Several Lp(a)-lowering drugs are currently being tested for CVD prevention, but none of them have been approved for clinical use yet.”
“[As Lp(a) levels are largely geneticaly determined], for individuals with very high Lp(a) levels, the most important thing is to lower overall CVD risk through living a healthy lifestyle and reduction of other traditional cardiovascular risk factors including LDL or non-HDL cholesterol, blood pressure, diabetes, obesity, and tobacco smoking.”
— Ask T. Nordestgaard, lead author
He also advocated medication where needed: “Aggressive LDL cholesterol lowering with statins, ezetimibe, and PCSK9 inhibitors is very important. PCSK9 inhibitors do actually lower Lp(a) levels but are not approved for this indication.”
“Yes,” says Nordestgaard, “we would argue that healthy individuals should be offered to have their Lp(a) levels measured at an early age, so that primary preventive measures may be initiated as early as possible.”
Wong agreed: “We should consider screening for lipoprotein(a) elevations, especially in people with a family history of heart disease. Lipoprotein elevations may affect up to 25% of the global population.”
However, she emphasized that even those with high Lp(a) can decrease their CVD risk:
“Currently, we recommend that people with lipid disorders such as lipoprotein elevation adopt a heart-healthy diet and regular exercise […] a heart-healthy lifestyle can improve cardiovascular outcomes despite the lipoprotein elevation.”
