Co-morbid alcohol abuse is common in individuals with psychiatric disorders. According to K.T.Brady 80% of alcoholics have an axis I disorder. The reverse also applies. More than 30% of anxiety and mood disorder patients and more than 50% of schizophrenics abuse substances. In bipolar patients, 60% have an alcohol problem at some point in their lives.
The destructive effects of alcohol abuse are thought to be proportional to the intake though gender matters. Clinically it has seemed that women suffer greater damage then men though this impression is confounded by a variety of variables that are difficult to control. Moderate drinking is generally considered to be 1 drink per day for women and 2 drinks per day for men. Heavy drinking is 5 drinks per day for men or 4 drinks per day for women. A drink is 12 oz. of beer or wine cooler, 5 oz (150 mL or cc) of wine, or 1.5 oz (45mL) of 80-proof distilled spirits. These all contain 12.5 grams of ethanol.
There are well-known and documented medical complications including cardiovascular, hypertension, hepatitis, pancreatitis, esophageal cancer, liver cancer, colon cancer. Neurological complications include decrease in grey and white matter, increased ventricular volume, and peripheral neuropathy.
I am limiting my additional comments to alcohol's effect on the brain in both males and females. Clinical observations support the notion that female alcoholics suffer more liver and cardiac damage as well as more motor problems and cognitive impairment than men. Women tend to be smaller and have a higher body fat content as well as a deficient stomach enzyme involved in metabolizing alcohol so that they achieve higher blood alcohol than men when taking in the same amount of alcohol. Yet more recent work indicates that sex does matter when assessing alcohol's effects though it is complicated. Daniel Hommer of NIMH Alcohol Abuse and Alcoholism division reported that alcoholic women lost 11.1% of their grey matter when compared to normal controls but alcoholic men lost 5.6% of their grey matter. For the white matter, the female loss was 8.2% and the male loss was 5.3%. The cerebral fluid volume increased by 24.1% in women and only 10.5% in men. This brain shrinkage had shown up by the time these alcoholics reached their early 30s. Some other work carried out at Stanford by Adolf Pfefferbaum has not found these differences. Unfortunately, there are a number of differences in these studies that leave the question unresolved.
To go to the next level of molecular or genetic insight, imaging is not enough and human subjects cannot be used. Enter Prendergast Littleton at University of Kentucky who identified a possible cause of damage in alcoholic brains. This molecule, spermidine, is released in rat brain tissue during alcohol withdrawal and its presence is associated with increased seizure activity in neurons. When Prendergast and Littleton dosed brains with alcohol and watched the amount of neuronal death during withdrawal. They fould no sex difference until they added spermidine. They think that spermidine is released in a normal reparative process but that in women it somehow goes awry and causes seizure activity in neurons already compromised by alcohol. This fits with another previous research finding. After glutamate attaches to the NMDA receptor allowing a measured quantity of Calcium ions to enter, if one add spermidine, then the pore through which Calcium ions flow in remains stuck open. This destroys the cell. This is worse in the female brain. When it comes to alcohol, sex matters.