JMERRAND on Surgery for Epilepsy

Published on February 2017 | Categories: Documents | Downloads: 8 | Comments: 0 | Views: 76
of 14
Download PDF   Embed   Report

Comments

Content

 

Working Paper & Decision Tree:

A comparison between surgery for temporal lobe epilepsy and changed medications

December 3, 2007 Jennifer Errande

Page 1 of 14

Errande’s Working Paper

Saturday, January 15, 2011

 

Background

Epilepsy has a prevalence prevalence of 5 to 10 per 10 1000 00 in North Am America. erica. Seizures in Temporal Lobe epilepsy can be very disabling to people who are otherwise healthy I was diagnosed with temporal lobe epil epilepsy epsy in 1976, at the ag agee of 2. I underwent surgery for temporal lobe epilepsy at Cedars Sinai Medical Center on Wednesday, June 22, 2005 2005 and have had no seizures since. I took my last medication in January of this year. 25,000 to 50,000 people will die of seizure related causes each year in the United States. The average indicate indicatess that approximately approximately 102.7 people die ffrom rom seizure related causes every every day. Approximately 91 91711 711 people in the United United States have died from seizure related causes since the day of my surgery. Surgical treatment of temporal lobe epilepsy was compared to medical treatment at the London Health Sciences Centre, Univeristy of Western Ontario, Canada between July 1996 1996 and August 200 2000. 0. 58 percent of the surgical patients were free of seizures, seizures, compared to o only nly 8 percent of the medical group patients. patients. 40  patients were assigned to each group. Only 4 (10 percent) of the surgical patients had adverse effects of surgery. Only two of those patients (5 percent of the entire surgical group) had effects on their verbal memory memory which interfered interfered with their o occupations. ccupations. It is estimated that only 1500 of the nearly 100,000 eligible patients undergo surgical procedures each year [1]. The median percentage improvement in the monthly frequency of seizures was 100 percent in the surgical group and 34 percent in the medical group. Problem Description and Discussion of Data

Page 2 of 14

Errande’s Working Paper

Saturday, January 15, 2011

 

Since the medical community has come to see surgery as a preferred treatment for TLE, the primary purpose of this paper is to convince patients to undergo surgery for temporal lobe epilepsy when advised to do so by their   physician. To simplify the process, I have designed a decision tree which can be shown to the patient. The primary purp purpose ose of the decision ttree ree is to demonstrate that surgery for temporal temporal lobe epilepsy iiss not as risky as many believe it to be. I have formatted the tree to also demonstrate that, in fact, a life with uncontrolled epilepsy is far riskier. In this decision tree, the cells which would normally display cash flows will display changes in one’s one’s quality of life. For the purpos purposee of this decision tree, I have chosen to create a formula which would allow a patient to rate five elements of their life on a scale from 1 to 10, allowing for for decimals. Allowing the patient to score their quality of life in the decision tree will make them feel that they are  participating in the calculations, and will help them accept the outcomes as being valid. The values will be doubled and summed up, so that the maximum possible value would be 100. The five elements which the patient will rate are health, material well-being, family life, community life with political stability, and job security[5]. For example, let’s assume that a patient with uncontrolled epilepsy rated each element of their life as follows: Health=4.5 Material well-being=6. well-being=6.3 3 Family life=4.8 Community life with Political stability=2.4 Job security=0 Page 3 of 14

Errande’s Working Paper

Saturday, January 15, 2011

 

After calculating the sum of all those values, and doubling the sum total, their quality of life score would 36 out of 100. The two branches I have chosen to include are related to the two most common choices made made by people with un uncontrolled controlled epilepsy. epilepsy. They will usually choose to undergo surgery, surgery, or ask to b bee given new medica medications. tions. I entered the quality of life score 36 as the first value both branches. Changed Medications

More than 70% with temporal lobe epilepsy continue to have seizures despite taking medications[6]. medications[6]. For the 30% fo forr whom medications medications work, I have created an event node with three additional branches, comparing the possible outcomes resulting from medication side effects. In many cases, the medicines have few side effects, but the side effects can sometimes be very severe. severe. There has also been evid evidence ence showing that an antiepileptic tiepileptic drugs can, in some cases, worsen seizure frequency or severity[4]. I created an event node to show the three possible outcomes relating to sideeffects of the medications. medications. There’s a 20% chance th thee medications will have few or  no side effects, in which case the quality of life stays as it was in the previous node. If the medication medicationss have moderate side eeffects, ffects, the quality of of life score could  be reduced by 30% of the original value. If the medications have severe side effects, a reduction of 70% can be made, showing that the quality of life is lower than it was before the change in medications. This a rare occuranc occurance, e, but should nonethe nonetheless less be taken into consideration.

Page 4 of 14

Errande’s Working Paper

Saturday, January 15, 2011

 

Overall, if the medications work to control the seizures, even taking into account all of the possible side effects, the change will be likely to have a positive impact on the patient’s life, improving their score by approximately 22%. In approximately 70% of cases of temporal lobe epilepsy, medications do not work to control seizures. Among the adults with epilepsy, 36% of those with active epilepsy reported  being physically disabled or unable to work [7]. A chance node can demonstrate the likelihood that an individual with uncontrolled epilepsy will be able to work. It will be assumed that that the 64% who can w work ork choose to do so. Their  selection of a job might might be impacted by their decision to d drive. rive. Driving can  present the person with more options, allowing them to choose from a wider range of jobs. Statistically speaking, epilepsy carries less risk for accidents than alcohol abuse and young age age drivers[8]. This is primarily b because ecause people who suf suffer fer from epilepsy taken great caution in choosing w when hen to drive. For this reason reason,, if a person with epilepsy takes a job which requires driving to access, they might take sick  days off when they are unable to drive because they feel they might be at risk for a seizure. If the person’s income is increased, their stress levels will probably increase as well, if only from fear of having their condition discovered. While there are laws protecting individuals from discrimination [9], inequities still exist. It is for this reason that I felt unable to add OR subtract from the quality of  life based on factors relating to work or driving. The last node on each of the branches relating to uncontrollable seizures will display the risk of death, which would bring one’s quality of life down to zero.

Page 5 of 14

Errande’s Working Paper

Saturday, January 15, 2011

 

“The lifetime risk of dying a seizure-related death (from status epilepticus, accidents or sudden unexplained death) is approximately 25 percent in patients with poorly controlled epilepsy.” [10] When this is taken into account, in the long run, the quality of life for  someone continuing to have seizures would be likely to average out to 25% less than what it was before before the decision wa wass made to avoid surge surgery. ry. The epilepsy will most likely worsen with time. Surgery

The statistics gathered at The London Health Sciences Centre, Univeristy of  Western Ontario, Canada were very po positive. sitive. However, since m medical edical science is continuing to advance, I felt the need to use statistics which were gathered more recently. [6] Using the most recent recent statistics I could find find,, I estimate that 70 70% % of patients who undergo the surgery will likely be completely freed of seizures. [2] The other  30% will be likely to have fewer seizures, needing fewer medications than they did  before the surgery. surgery. Reducing the dosage dosage of anti-epileptic me medication dication has been associated with improved cognition [3], which would in turn improve one’s quality of life. Since the patient will likely need fewer medications than they needed before the surgery, I saw no need to calculate the risks relating to the side-effects. I would estimate that freedom from seizures would greatly decrease the impact the epilepsy epilepsy has had on the patient’ patient’ss life. However, since some adjustments might have to be made to live without seizures, I will estimate that the impact will only be lessened by 70%.

Page 6 of 14

Errande’s Working Paper

Saturday, January 15, 2011

 

If the patient must continue to take medications, and have occasional seizures, the impact might be lessened to 50%. However, since the seizure frequency is greatly reduced, there is no need to calculate the risk of a seizure related death as I did in the branch related to a change in medication. medication. One patient in the medical medical group died a sudden, unexplained death in in the London Healt Health h Sciences Centre study. No deaths occurred in the surgical group. 10% of the patients in the Ontario study had adverse affects from the surgery. Only 5% had affe affects cts which impacted th thee work performance. I created an event note to show that risk. Reading descriptions o off those effects, I decided decided that the worst possible effect that those effects could have on one’s life would be one third of the score given for the quality of life at the beginning. I then felt it necessary to create a decision node, after the branch demonstrating the possibilit possibility y of adv adverse erse effects from the surgery. The patient must decide how they will adapt to life without epilepsy, with (or without) adverse affects. Making a conscious eff effect ect to iimprove mprove on one’s e’s life can increas increasee one’s qua quality lity of life life by at least 50%.

I actu actually ally feel that lif lifee can improve far m more ore than that.

Looking at the decision tree, and all the resulting computations, it is clear that the surgery will likely increase one’s quality of life, whereas a change in medication will likely decrease their quality of life in the long run, if the seizures are not controlled. Analysis of Results

I recognize that some members of the medical community might disagree with my calculations. calculations. It is for that rreason eason that I had to aaccess ccess the numbers fro from m different resources, which supported my own experience.

Page 7 of 14

Errande’s Working Paper

Saturday, January 15, 2011

 

I should also explain why I chose to for format mat the calculation calculationss the way I did. In my own experience, my quality of life score before the surgery would have been 50. After the surgery, despite the complica complications, tions, my quality o off life quickly ro rose se to 85. That is an 70 70% % increase. However, I know that w when hen I was fe fearful arful of su surgery rgery I would have rated my life higher in order to justify my avoidance of surgery.

It

is for that reason that, rather than calculating the change as: Q2 = Q1 * 1.7 I formulated it as: Q2=Q1+ .7 * (100-Q1) I formulated quality of life improvements as decreases in the impact of  epilepsy. An overly optimistic (or fear fearful) ful) patient might sc score ore their life as: Health=8 Material Well-Being=9 Family Life=8 Community Life=9 Job Security=8.5 Their quality of life life score would be 85. The formulas I wrote wrote would show that having the surgery would increase their life to 96, and changing medications would be likely to to bring it down to 75.7. This is taking into acc account ount the possibility that the new medications won’t work, and the possibility of a seizure related death. I welcome any suggestions, comments and questions about how I have structured this paper. paper. I hope that some me members mbers of the medic medical al community will take interest in my calculations, and give feedback on how its structure can be improved. Since I have never worked in the me medical dical industry, I will need input from others to make a truly effective paper.

Page 8 of 14

Errande’s Working Paper

Saturday, January 15, 2011

 

In compiling all the data needed for this paper, I came across many elements which could not be included in this particular analysis. Unfortunately, there are many patients with temporal lobe epilepsy who have been told that they are not candid candidates ates for surgery. It is possible that they have  been examined examined using outdated te technologies. chnologies. Medical tec technologies hnologies ar aree impro improving, ving, which makes me confident that many of those patients will soon be considered candidates for surgery. It is important to also assess the cost savings that come from surgery for  temporal lobe epilepsy, epilepsy, if only to convince convince the insuranc insurancee providers to cover it. The approximate yearly cost of medical care is $2,094 in patients with persisting seizures vs $582 in patients patients who have unde undergone rgone surgery. [16] [16] The cost of an MRI study can range from from $400 to mo more re than $2000. I will average th those ose numbers out to $1200. The cost of an EEG is app approximately roximately $1 $1000. 000. This means that the total annual cost of epilepsy is approximately $4294. Insurance providers of patients who have undergone the surgery are saving $3712  per year. This is less than the cost o off travels which mi might ght be required for for a patient to be examined and operated on in the most technologically advanced facility. I will base the following following calculations on my own surgery. This is how much the hospital charged for each element of the surgery: Surgery:

$113,086.90

Video EEG:

$10,967.34

MRI

$4,821.38

Hosp Ho spit ital al St Stay ay aft fter er surg surgeery ry::

$48,9 48,91 12. 2.7 75

Page 9 of 14

Errande’s Working Paper

Saturday, January 15, 2011

 

The entire entire cost of my surgery was $1 $177,788. 77,788.

The savi savings ngs in medical costs

will compensate compensate for that cost in approxi approximately mately 48 years. This is not not taking into account many other other medical costs which h have ave decreased. Epilepsy can cause a wide range of health problems which might seem unrelated. Much of the compensation compensation will also go tow toward ard the patient. People with epilepsy who are employed full-time make an average income of $27,008 a year. In 2006, the median annual income according to the US Census Bureau was determined to be $48,201. This means a likely incr increase ease in income of $ $21,193 21,193 after  having surgery. This means that, assuming tthe he surgery costs $17 $177,788, 7,788, the cost will be recovered within 8.4 years. However, I don’t want peopl peoplee with epilepsy to p pay ay for the surgery out of  their own bank accounts. accounts. The surgeries should de definitely finitely be covere covered d by insurance, or even by the government, if necessary. Epilepsy affects about 2.7 million Americans, and results in an estimated annual cost of $15.5 billion in medical costs and lost or reduced earnings and  production. Assuming each surgery costs $177,788.37, $15.5 billion would cover  the cost of 87182 surgeries. If you operate on the highest possible number that could die (50,000) (50,000) at a cost of $177,788.37 $177,788.37 per surger surgery, y, society in general would would  be left with approximately 6.6 billion dollars in savings. There is one last element element which needs to be ad addressed. dressed. By 2003 the numbe number  r  of practicing neurosurgeons neurosurgeons had dropped dropped to 3,080. In the United State States, s, about 2.5 million people people have epilepsy. To operate on everyon everyonee with epilepsy with within in one year, taking only weekends off, each neurosurgeon would have to operate on 3.11  patients per day.

Page 10 of 14

Errande’s Working Paper

Saturday, January 15, 2011

 

This is why it’s important for patients to undergo the surgery as soon as the opportunity is presented presented to them. There will come a da day y when surgeons wil willl have waiting lists and patients might have to wait years to undergo the surgery. Fortunately, medical medical technology is adva advancing. ncing. Intuitive Surgi Surgical cal Inc. (ISRG)  produced the DaVinci DaVinci Surgical Syst System. em. I hope that thi this, s, along other medi medical cal technologies, will motivate more medical students to take interest in the field of  neurosurgery. As more people with epilepsy undergo the surgery, there will be more  people working to inform others about how good the outcome can be and thereby alleviate the fears that they may currently have. I would like everyone everyone with temporal lobe epilepsy to experience the miracle that I have experienced in the last 2 years. By helping to alle alleviate viate the patients’ ffears ears of the surgery, and disclosing health options which are available to them, I hope that I will help more people experience life without epilepsy.

Page 11 of 14

Errande’s Working Paper

Saturday, January 15, 2011

 

References

[1] Wiebe, Md, S., Blume, Md, W. T., Girvin, Md, Phd, J. P., & Eliasziw, Phd, M. (2001). A Randomized, Controlled Trial of Surgery for Temporal-Lobe  Epilepsy. :

[2]Berg, A. T., Langfitt, J. T., Spenser, S. S., & Vickrey, B. G. (2007). Stopping antiepileptic drugs after epilepsy surgery: A survey of U.S. epilepsy center  neurologists. Epilepsy & Behavior, 10, 219-222. [3]Motamedi, G., & Meador, K. (2003). Epilepsy and Cognition. Epilepsy and   Behavior, 4, S25-S38.

[4]Sazgar, Md, M., & Bourgeois, Md, B. Fd (2005). Aggravation of Epilepys By Antiepileptic Drugs. Elsevier, , 227-233. [5]"The Economist's Human Development Report" http://www.economist.com/media/pdf/QUALITY_OF_LI http://www.economist.com/media/pd f/QUALITY_OF_LIFE.pdf FE.pdf (November  25, 2007) [6] "Temporal lobe seizure" http://www.may http://www.mayoclinic.com/health oclinic.com/health/temporal-lobe/temporal-lobeseizure/DS00266/DSECTION=7 seizure/DS00266/ DSECTION=7 By Mayo Clinic Staff Jun 25, 2007 [7] Boyles, Salynn "Many Adults With Epilepsy Not Treated -Burden of Disorder  Has Great Impact on Quality of Life Study Shows" http://www.webmd.com/epilepsy/new http://www.webm d.com/epilepsy/news/20071031/many s/20071031/many-adults-with-adults-with-

Page 12 of 14

Errande’s Working Paper

Saturday, January 15, 2011

 

epilepsy-not-treated?src=rss_psychtod epilepsy-not-treate d?src=rss_psychtoday ay WebMD Medical News: Oct. 31, 2007 [8]Ettore Beghi, Laboratory of Neurological Disorders, Milan, Italy "Epilepsy and driving-Regulations in the European Union need harmonisation as well as driving-Regulations greater flexibility" http://www.bmj http://www.bmj.com/cgi/content/fu .com/cgi/content/full/331/7508/60 ll/331/7508/60 July 9, 2005 [9] "Questions And Answers About Epilepsy In The Workplace And The Americans With Disabilities Act (ADA)" http://www.eeoc.gov/facts/epilepsy.ht http://www.eeoc.g ov/facts/epilepsy.html ml August 24, 24, 2004 [10] Marks, Garcia University of California, San Francisco, School of Medicine "Management of Seizures and Epilepsy" http://www.aafp.org/afp/980401a http://www.aafp.o rg/afp/980401ap/marks.html, p/marks.html, April 1, 1998 [11] Weiner M.D, Howard L. "A randomized study of the effectiveness of epilepsy surgery" http://www.epilepsy.com/epilepsy/surgery_results, http://www.epilepsy.com/epilepsy/surgery_results, March 8,2004 [12] Chowdhry, Bhagwan "Possibility of dying as a unified Explanation of (i) why we discount the future, (ii) get weaker with age, and (iii) display riskaversion" January 26, 2007 [13] http://en.wikipedia.org [14] Doherty, Gates, Penovich, Moriarty “SUDEP In An Intractable Epilepsy Population” http://www.mnepilepsy.org/PDFs/21091.pdf 

Page 13 of 14

Errande’s Working Paper

Saturday, January 15, 2011

 

[15] "Methodist Hospital Obtains New MRI Scanner Technology" http://www.insideindianabusiness.com/n http://www.inside indianabusiness.com/newsitem.asp?ID=177 ewsitem.asp?ID=17732&print=1 32&print=1 updated: 4/24/2006 1:38:21 PM

[16] Langfitt, Holloway, McDermott, Messing, Sarosky, Berg, Spencer, Vickrey, Sperling, Bazil, Shinnar "Health care costs decline after successful epilepsy surgery" Neurology • 2007 Apr;68(16):1290Apr;68(16):1290-8 8 [17] http://en.wikiped http://en.wikipedia.org/wiki/Househ ia.org/wiki/Household_income_in_th old_income_in_the_United_States e_United_States [18] http://www.cdc.gov/Epilepsy/ http://www.cdc.gov/Epilepsy/

Page 14 of 14

Errande’s Working Paper

Saturday, January 15, 2011

Sponsor Documents

Or use your account on DocShare.tips

Hide

Forgot your password?

Or register your new account on DocShare.tips

Hide

Lost your password? Please enter your email address. You will receive a link to create a new password.

Back to log-in

Close