Part I of our Underwriting Liver Function Blog Series:
Picture this. You are visiting the doctor for a check-up, answering a slew of questions to help them understand your current state of health. Waiting slowly but surely for that dreaded question (at least for some of us!) to come up... 'How many drinks do you have on average per week?'. At the risk of sounding 'unhealthy' you fudge the numbers slightly - perhaps subtract one or two or four.
Sound like a familiar confession? Perhaps you leave the appointment thinking - does my doctor really know how much I drink? We'll, I can't speak from a doctor's perspective, but as a life underwriter, this information is something I care about getting to the bottom of. This information is critical to our profession in order to be able to determine over-consumption of alcohol and its effect on the liver.
I'll be sharing a series of articles on underwriting liver function to provide fellow underwriters with an informative summary of tests to evaluate liver disorders, and what you can infer from them. But before I dive in, let’s answer the question that is on your mind.
Can your weekly alcohol assumption be measured?
Well, the good news for those who like to indulge, is that besides the seldom-used BAC test , there is no sure-fire way to measure this with 100% accuracy. Plus, to be honest, the BAC test would only spell a lot of trouble if you were heavily imbibed at the time of testing.
Of course, this can be problematic for an underwriter that needs to make heads or tails out of abnormalities in liver function testing. But there are a number of tests (some better than others) that we can utilize to this end. I like to think of them as pieces of a puzzle, so to speak – that when used in combination can give us excellent insight into how a patient’s liver is operating or not! Many of these tests are useful in evaluating liver disorders beyond alcoholism as well. Moral of the story, I suppose your doctor does have the ability to know how much you drink!
Now let’s get back to the series, I’ll kick things off with liver enzyme testing.
Liver Enzymes – our first look
If you’re a seasoned underwriter, then you’re probably thinking that this is a red herring – after all, liver enzymes aren’t true liver function tests. First, because elevations in these tests do not necessarily correlate with liver impairment, and second, declining liver function can be masked by apparently normal liver enzymes. However, I still think it’s a good starting point for two reasons:
We see them on every insurance lab profile
- The patterns of elevations can help you to make some good inferences.
What are the liver enzymes?
- AST, or aspartate aminotransferase
- ALT, or alanine aminotransferase
- GGT, or gamma-glutamyl transferase
Enzymes, by nature, catalyze reactions. When you see elevations in these particular enzymes, there has likely been some tissue damage which has led to these enzymes being activated. The caveat is that none of the above enzymes are unique to the liver. ALT may be the most highly concentrated there, but AST is also prominent in the kidneys, heart, muscle tissue, pancreas, and red blood cells, and GGT is even more ubiquitous.
However the key is to watch for patterns in these enzymes.
In the case of excessive alcohol intake, AST rises more sharply than ALT, such that the AST/ALT ratio would be >1. GGT spikes are often seen alongside this.
In cases of biliary tract disorders or blockages (e.g. gallstones most commonly, sclerosing cholangitis in rarer cases), GGT spikes are seen in combo with elevations of another enzyme:
- ALP, or alkaline phosphatase
What is Alkaline Phosphatase?
ALP itself is mostly made in the liver and bones but can be found in other tissues. Life underwriters should be most concerned with elevations when they are in conjunction with the afore-mentioned enzymes (mainly GGT).
What does an isolated elevated GGT mean?
Lone GGT spikes are perhaps the most difficult risks to quantify here. GGT is an enzyme for lipid metabolism and antioxidant production; therefore, elevations would imply a state of oxidative stress, caused by free radicals. At the organ level, you will probably be most concerned with fatty liver disease if not increased alcohol intake, but arterial disease and cancers should be considered.
That covers the first set of tests to be aware of for evaluating liver disorders.
Stay tuned for the next blog in the series where I turn the following into a (believe it or not) sing-a-long!
- Albumin and Globulin
- CDT and HAA