What Influences Lab Results?

What Influences Lab Results

Blood taken from insurance examinations are subject to many possible influences. Delays in handling, processing, and different atmospheric conditions may causes changes to lab results as opposed to those you would avoid when the labs are processed locally. There are also many body physiologic conditions (childhood, pregnancy, fasting, alcohol intake) that also influence test results. Insurers and underwriters are usually aware of these possibilities from the get-go, but when conditions are abnormal in a setting that is completely unexpected, it helps to know the extenuating circumstances that are involved.

Let’s start with physiologic factors. Young growing children (generally up to the age of 22) have active bone growth and turnover, and often labs that are abnormal for others are normal for them. They include alkaline phosphatase, AST and ALT, GGTP and LDH. Alkaline phosphatase particularly can be high, and in peak growth years be several times normal. It’s all part of the growing process however, and that is their normal.

Many times bloods are done fasting. This is recommended because blood sugar, cholesterol and triglycerides are optimal in a fasting state and allow the applicant to put his best foot forward. Alkaline phosphatase, GGTP and especially triglycerides will elevate if blood is taken within two hours after a meal. A prolonged fast may raise bilirubin and uric acid, but drop albumin, glucose and protein. High protein diets will raise both BUN and uric acid.

Pregnancy is one of the hardest situations for interpreting a blood test. Virtually every lab value is affected. Albumin, BUN, protein and creatinine may decrease. That is rarely a concern, but alkaline phosphatase, uric acid and urine protein may be increased. Cholesterol, triglycerides and HDL in particular may rise, and sometimes take a preferred case and throw the values well out of normal range. It makes the blood test during pregnancy of restricted usefulness in the underwriting process.

Mechanical problems can influence the sample. If, for whatever reason, there is a marked delay between obtaining the sample and running it, it often provides invalid values. Liver function tests, alkaline phosphatase, bilirubin, GGTP and glucose may drop off the map depending on how long the delay was. A1C might artificially rise, which can cause a problem. The mail has a way of making detours and, as such, processing problems may interfere with accurate determinations.

Heat in a sample can cause rises in both BUN and creatinine, simulating a kidney problem. Liver function tests, GGTP and glucose all drop. At times the lab may not be able to record a value for glucose based on the degree of heat involved. The drop may also influence A1C and cause a consideration for insurers trying to guess at what an actual value might have been.

Finally, a condition called hemolysis can exist when a sample is either knocked around too much, suffers trauma of some sort, or the blood is squirted too quickly or too forcefully through a needle into the collecting tubes. The blood cells break apart and chemistries such as albumin, AST, ALT (liver function tests), bilirubin, cholesterol and triglycerides can be reported artificially high. On the other end, it may lower fructosamine, hemoglobin A1C and triglyceride values.

Most samples are collected and transported without any problem, much like even blood testing that is done for a personal physician. Because insurance testing is more standardized and only specific laboratories are used, the handling process is subject to more variables and longer time for a sample to reach its destination. As such, an underwriter generally looks at all aspects of the sample process when assessing the results, just like he or she may have to consider different body disease and conditions to assess the readings correctly and appropriately.

Robert Goldstone, MD, FACE, FLMI, board certified internist and endocrinologist, was most recently vice president and chief medical officer for Pacific Life and Pacific Life and An­nu­ity. He has extensive brokerage and life insurance experience, having been medical director at both MetLife Brokerage and Transamerica Occidental Life.

Goldstone is board certified in insurance medicine and the inaugural recipient of the W. John Elder Award for Insurance Medicine Journalism Excellence. He was also honored as a fellow of the prestigious American College of Endo­­­crinology and has written monthly for Broker World since 1991.

Goldstone does consulting full or part-time as well as on a fill-in basis for companies who need a medical director/physician. He can be reached by ­telephone at 949-943-2310. Emaill: drbobgoldstone@yahoo.com.

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