- In a large study of male veterans, both low and high HDL cholesterol levels were associated with higher risks of dying prematurely compared with intermediate levels, forming a U-shaped curve.
- The beneficial properties of HDL cholesterol were attenuated, but remained significant, in the presence of kidney disease.
Washington, DC (August 11, 2016) -- A new study indicates that maintaining an intermediate level of high density lipoprotein cholesterol (HDL-C) may help people live longer. The study, which appears in an upcoming issue of the Clinical Journal of the American Society of Nephrology (CJASN), found that both low and high HDL-C levels were linked with a higher risk of premature death. Also, intermediate HDL-C levels were associated with a lower risk of death across all levels of kidney function.
Patients with kidney disease often have reduced levels of HDL-C, which may partly explain their higher risk of dying prematurely; however, the relationship between HDL-C and premature death in patients with kidney disease is unclear. To investigate, a team led by Benjamin Bowe, MPH and Ziyad Al-Aly, MD, FASN (Washington University School of Medicine and VA Saint Louis Health Care System) retrospectively studied 1,764,986 US male veterans with at least one measurement of kidney function and one measure of HDL-C between October 2003 and September 2004. Participants were followed until September 2013.
The researchers found that both low and high HDL-C levels were associated with higher risks of dying during follow-up compared with intermediate HDL-C levels, forming a U-shaped relationship between HDL-C and mortality risk. The beneficial properties of intermediate levels of HDL-C were attenuated, but remained significant, in the presence of kidney disease.
"The finding that high HDL-C was also associated with higher risk of death was not expected and has not been reported previously in large epidemiologic studies such as the Framingham Heart Study and others," said Dr. Al-Aly. "Prior epidemiologic studies significantly advanced our understanding of the relationship between cholesterol parameters and clinical outcomes; however, these studies are limited in that the number of patients in these cohorts is relatively small compared with the current Big Data approach." He noted that a Big Data approach allows a more nuanced examination of the relationship between HDL-C and risk of death across the full spectrum of HDL-C levels.
"Our findings may explain why clinical trials aimed at increasing HDL-C levels have failed to show improvement of clinical outcomes," noted Bowe.
Study co-authors include Yan Xie, MPH, Hong Xian, PhD, Sumitra Balasubramanian, MS, and Mohamed Zayed MD, PhD.
Disclosures: The authors reported no financial disclosures.
The article, entitled "High Density Lipoprotein Cholesterol and the Risk of All-cause Mortality among U.S. Veterans," will appear online at http://cjasn.asnjournals.org/ on August 11, 2016, doi: 10.2215/CJN.00730116.
The content of this article does not reflect the views or opinions of The American Society of Nephrology (ASN). Responsibility for the information and views expressed therein lies entirely with the author(s). ASN does not offer medical advice. All content in ASN publications is for informational purposes only, and is not intended to cover all possible uses, directions, precautions, drug interactions, or adverse effects. This content should not be used during a medical emergency or for the diagnosis or treatment of any medical condition. Please consult your doctor or other qualified health care provider if you have any questions about a medical condition, or before taking any drug, changing your diet or commencing or discontinuing any course of treatment. Do not ignore or delay obtaining professional medical advice because of information accessed through ASN. Call 911 or your doctor for all medical emergencies.
Since 1966, ASN has been leading the fight to prevent, treat, and cure kidney diseases throughout the world by educating health professionals and scientists, advancing research and innovation, communicating new knowledge, and advocating for the highest quality care for patients. ASN has nearly 16,000 members representing 112 countries. For more information, please visit http://www.asn-online.org or contact us at 202-640-4660.
Clinical Journal of the American Society of Nephrology