MIAMI BEACH — Male physicians who decreased or maintained a low body mass index and/or started or continued to drink an average of one or more alcohol drinks per day experienced small but significant improvements in their HDL cholesterol levels at 14 years' follow-up, according to a study.
“What is exciting is you may not have to take medication to modify your HDL,” Dr. Catherine Rahilly-Tierney said in an interview. “The overall theme is you can change your life and future if you lose weight or initiate moderate intake of alcohol.”
She and her colleagues assessed 4,501 male physicians participating in the Physicians' Health Study who had HDL cholesterol levels measured in 1982 and in 1997. Their aim was to determine how doctors in this longitudinal study achieved a significant decrease in risk of coronary heart disease by increasing their HDL levels, as previously reported (Am. Heart J. 2008;155:869-75).
The investigators studied self-reported changes in body mass index, alcohol intake, physical activity, and smoking status. The objective was to demonstrate that lifestyle changes could have a beneficial impact because, unlike LDL cholesterol, there are few well-tolerated medications to improve HDL cholesterol levels, Dr. Rahilly-Tierney said during a poster session at the annual meeting of the Society of General Internal Medicine.
“We found the biggest drivers of HDL change were BMI and alcohol intake, which we expected based on what we know about the relationship between these and HDL,” said Dr. Rahilly-Tierney, a researcher with Massachusetts Veterans Epidemiology Research and Information Center (MAVERIC), Boston Veterans Affairs Healthcare System.
The mean HDL cholesterol change in the entire cohort was an increase of 0.88 mg/dL. However, doctors who maintained an ideal BMI, defined as 25 kg/m2 or less, achieved a statistically significant 3.5 mg/dL increase in HDL cholesterol.
Similarly, participants who lowered a higher baseline BMI to 25 kg/m2 or less experienced a statistically significant increase of 5.1 mg/dL.
“BMI and alcohol intake seemed to be the most important factors, but this is not applicable outside this study yet. We had a limited demographic,” Dr. Rahilly-Tierney cautioned.
Strengths of the study include a 99% follow-up rate and clean, accurate data, she said.
Doctors who reported drinking one or more alcoholic beverages daily at baseline and at follow-up had an HDL cholesterol increase of 2.6 mg/dL. Those who reported drinking less than one alcoholic beverage per day in 1982 but who increased their alcohol intake to one or more drinks per day in 1997 achieved an increase of 2.2 mg/dL. These differences were statistically significant, although moderate, Dr. Rahilly-Tierney said.
In contrast, participants who decreased alcohol intake from one or more daily beverages to less than one per day experienced a mean HDL cholesterol decrease of 2.6 mg/dL.
Other lifestyle factors, including changes in physical activity and smoking status, were not significantly associated with changes in HDL cholesterol levels, but this may have been due to small numbers of smokers and physically inactive participants in this cohort, Dr. Rahilly-Tierney said. The researchers used linear regression to adjust for patient age, hypertension, diabetes mellitus, parental history of myocardial infarction, cholesterol-modifying therapy, and baseline HDL cholesterol.
'We found the biggest drivers of HDL change were BMI and alcohol intake.' DR. RAHILLY-TIERNEY