Wednesday, May 23, 2012

Why alcoholics have a lower risk for coronary heart disease

The Spanish EPIC cohort study (European Prospective Investigation into Cancer), published in 2010, including 15630 men and 25808 women, has concluded that alcohol intake (moderate, high and very high consumption) in men aged 29–69 years was associated with a more than 30% lower CHD incidence (1).

Reading an old article by Leary (2) from 1935, I see that his interest in arteriosclerosis arose out of information that a class persons suffering from alcoholism appeared to show a lesser degree of atherosclerosis than their ages would justify. So, I have searched for recent papers that could confirm this relationship and found a study from 1997 comparing a
cohort of alcoholics who underwent a medico-legal autopsy during a five-year period with non-alcoholic controls who did not differ from the alcoholics in selection criteria. This study has show in the examinations, that alcoholic men and old women had a significantly lower degree of atherosclerosis in the coronary arteries (3)

A paper published in 2002 may have the answer to why alcoholics have a significantly lower degree of atherosclerosis in the coronary arteries and risk for coronary heart disease (4). Regarding this paper, a release from EurekAlert (5), with an interview by William Lovallo, one of the authors, told that:

“Before testing alcoholics for their responses to a public-speaking task, researchers first needed to establish if their sympathetic nervous system was able to respond at all. "This would tell us if their blunting was specific to psychological stressors like public speaking," said Lovallo, "or due to a generalized autonomic deficit."

He and his colleagues examined 20 alcohol-dependent subjects, abstinent for 21 to 28 days, and 10 age-matched nonalcoholics. All subjects were males between the ages of 22 and 55 years. The researchers used impedance cardiography and dinamap blood pressure monitoring to assess the participants' heart rate, stroke volume, cardiac output, total peripheral resistance, mean arterial pressure, systolic blood pressure, and diastolic blood pressure during orthostasis and public speaking. Self-reported mood was also assessed during these two tasks.

Cardiovascular responses to orthostasis were similar for the two groups. However, the alcoholics had blunted heart-rate responses to public speaking even though they reported similar anxiety responses to the nonalcoholics. This suggests a disconnection between perception of threat and resulting physiological responses among the alcoholics.

"The similar cardiovascular responses to orthostasis among the alcohol-dependent patients indicate that their autonomic nervous systems were working normally," said Lovallo. "Yet when we asked them to prepare and memorize a short speech and then deliver the speech to a video camera, the patients reacted with little or no change in heart rate, and of course, they failed to have a cortisol response. The patients reacted as if the social challenge of public speaking had no special meaning for them. So, the sympathetic nervous system in the patients looked normal, but their response to a psychological stressor was almost absent. When faced with a socially meaningful stressor, neither part of their fight-flight mechanism was working."

These results support the concept of the acidity theory where sympathetic predominance is the primary factor leading to atherosclerosis (6)

Carlos Monteiro

1. L Arriola, P Martinez-Cambor, N Larranaga, M Basterretxea. Alcohol intake and the risk of coronary heart disease in the Spanish EPIC cohort study. Heart 2010;96:124-130 doi:10.1136/hrt.2009.173419
2. Leary T. Atherosclerosis, the important form of arteriosclerosis, a metabolic disease. Vol 104, N7. JAMA, 1935
3. Thomsen JL. Atherosclerosis in alcoholics. Forensic Sci Int. 1995 Oct 30;75(2-3):121-31 and in Ugeskr Laeger. 1997 Feb 3;159(6):757-.60
4. Tera L. Panknin, Stacey L. Dickensheets, Sara J. Nixon, William R. Lovallo. Attenuated Heart Rate Responses to Public Speaking in Individuals With Alcohol Dependence. Alcohol Clin. Exp. Res. 2002 Jun; 26 (6): 841
5. Alcoholics have 'blunted' responses to psychological stressors such as public speaking. Public release date: 17-Jun-2002 at
6. Carlos ETB Monteiro, Acidic environment evoked by chronic stress: A novel mechanism to explain atherogenesis, 2008 at