Frontotemporal dementia

We present the case of a 51-year-old former U.S. Air Force officer who developed marked behavioral and personality changes over a 9-year period, ultimately leading to his discharge from the Air Force at a rank below that which he achieved during service. Clinical diagnostic features, neuropsychological testing and neuroimaging together confirmed a diagnosis of frontotemporal dementia. This form of presenile dementia is discussed with reference to his case.

Introduction

Presenile dementia is a term often used synonymously with Alzheimer's disease. There are, however, other forms of dementia unlike that of Alzheimer's disease and vascular dementia that occur in the presenile age range. Focal degeneration of the frontotemporal lobes is a relatively common cause of dementia, comprising approximately 20% of cases.1 The underlying pathology is quite distinct from that of Alzheimer's disease without the presence of amyloid plaques and neurofibrillary tangles and with different primary areas of atrophy. The clinical presentation is also quite distinct with an emphasis on impairment of executive functioning rather than on memory functions.2,3 Frontotemporal dementia (FTD) is a disease of unknown etiology that affects men and women equally with maximal prevalence between the ages of 45 and 65 years.4 It is insidious in onset, causing alterations in personality and social conduct, characterized by social disinhibition and distractibility, yet with relative preservation of memory function.1,5-7 The patient normally presents with evidence of lapses in judgment, emotional blunting, loss of insight, and deterioration of personal hygiene and appearance. In addition, there are cognitive deficits especially in the areas of attention, abstraction, planning, and problem solving.8

Case Presentation

S.C., a 51-year-old white man, was brought to the urgent care clinic at the Veterans Administration Hospital in San Antonio, Texas by his sister in August 2001. She was concerned about his current living conditions, neglect of personal hygiene, and the evidence of serious errors of judgment on his part with respect to his finances. The patient himself appeared to be completely unconcerned about his behavior and appearance.

Until August 2000, S.C. was a Lieutnant Colonel in the U.S. Air Force, maintaining a high standard of performance and achieving the impeccable standards of personal presentation and behavior necessary for an officer of that rank. He was a family man, married with four children, and had a self-reported close relationship with his family.

However, S.C.'s behavior began a subtle transformation as early as 1991. His family reported vague incidents of atypical behavior, for example hanging up the telephone in the middle of conversations with no apparent warning. None of these events were alarming, but these odd behaviors were enough to make an impression, especially in hindsight.

By 1997, S.C.'s life was in a steady decline. He was under investigation by the U.S. Air Force for downloading pornographic material from the Internet onto government computers. He attended a family wedding looking unwashed and unkempt. During the reception, he overreacted toward a young nephew, slapping, choking, and throwing him to the ground. Immediately afterward, he went back to his table and acted as if nothing unusual had just occurred. Following the wedding, S.C. was due to fly to Korea for a period of 3 years of active service. He left his family without a single goodbye with no acknowledgment of the amount of time he was to be away or where he was going.

His wife filed for divorce in January 2000 because of his increased interest in pornography and his increasingly erratic behavior. In October 2000, after serving for 21 years, S.C. was granted an honorable discharge from the U.S. Air Force as a Major. He was demoted from the rank of Lieutenant Colonel in response to the investigations into his behavior after the misconduct charges against him were upheld.

S.C. has been living in San Antonio since March 2001 in a house he purchased while stationed there in the Air Force. He rented a room in his home to a 19-year-old man whom he had never met before for $120 per month. This young man appears never to have paid S.C. any rent for his accommodation. In addition, he convinced S.C. to cosign for a new car for his sole use, and according to the patient's sister, he has practically demolished S.C.'s house.

S.C. has recently been unable to hold down even the simplest employment. In the 10 months since his discharge from the U.S. Air Force, he has had five different jobs such as working at a fast food establishment. He has been fired from each of these. His inability to perform these menial jobs is in sharp contrast to his employment history and his education level, holding a master's degree. He has gained an excess of 88 kg due to a diet of soft drinks and candy and an increased inactivity, mainly consisting of hours spent watching television.

The evening before his admission to the Audie Murphy Veterans Affair Psychiatric unit, S.C. displayed a range of inappropriate behaviors. At a grocery store, he wandered in a distracted fashion and insisted on replacing any items he found that were not on the correct shelf into the right position. He is reported to have defecated in his sister's car and to have stood in the middle of the living room naked while urinating on the couch.

S.C. has a history of depression, with treatment, for the 2 years prior to his discharge from the U.S. Air Force. The only family history of psychiatric conditions is chronic depression, for which his mother and two younger siblings are currently undergoing treatment. The patient denied substance abuse, use of any medications, or any previous hospitalizations. He has no forensic history.

S.C. was orientated in both time and space. He showed intact recent and remote memory, comprehension, and calculating, reading, and spelling abilities. He demonstrated poor concentration and attention at several points during the interview and displayed marked impersistence on testing. His intellectual function, however, appeared average with a good basic vocabulary and an excellent general fund of knowledge. His estimated premorbid full scale IQ was 108 + or - 10. However, this score was judged by the examiner to be an underestimate of his previous ability. He was markedly hampered by his tendency toward impulsive responses. Instead of attempting to read words as they were written, S.C. substituted similar looking, more familiar words.

S.C.'s speech was linguistically correct, yet the content was frequently off the point. He showed a tendency toward the production of stereotyped phrases and toward echolalia. There was a marked discrepancy between his above average ability to discuss the similarities between items and his markedly literal interpretation of simple common proverbs. He was generally courteous, although markedly disinhibited, talking slightly too loudly, asking inappropriate personal questions, and offering irrelevant extra information without regard for its contextual significance. The patient demonstrated agitation throughout his initial interview by continually twisting a candy wrapper and capping and uncapping a soda bottle repetitively without drinking from it. His concentration span was limited and he showed increased distractibility and psychomotor activity.

S.C.'s mood was euthymic without increased or decreased intensity of affect. His affective expressions were appropriate to content. He denied suicidal or homicidal ideation, auditory or visual hallucinations, and ideas of reference and appeared to hold no obsessional or delusional beliefs. The patient had very poor insight about his condition. He understood that he was in the hospital because his sister was worried about him but he denied his need to be there and denied that he had been behaving abnormally.

S.C.'s physical examination was unremarkable with the exception of marked hyperreflexia bilaterally in both upper and lower limbs. He had negative Babinski sign bilaterally. No fasciculations were observed. His gait was normal, and he showed no alteration in strength, sensation, or coordination. He was continent of urine and feces and there was no reported history of problems with continence.

On formal psychological examination, S.C. was cooperative yet distractible and restless. He scored 30 of 30 on the Mini-Mental State Examination. His ability to name objects, tested using the Benton Naming Test, was above average ( 1.3 SD above a mean performance). His memory was intact for both day-to-day events and word lists. He particularly excelled on a measure of delayed free recall, scoring 2 SD above the mean. In contrast, his memory of a complex geometric design (the Key Complex Figure) was average, and his ability to copy the figure was in the poorest percentile of the population.

On a battery of tests designed to specifically test frontal lobe function, S.C.'s performance was variable. He scored 5.2 SD below a mean score on the Behavioral Dyscontrol Scale. This extremely poor performance was attributed to significant motor perseveration, impulsivity, and interference problems. He scored 2 SD below the mean on the FAS, a test that requires the patient to freely generate as many words as possible beginning with a specified letter of the alphabet within a minute. This marked reduction in verbal fluency was mainly attributable to impersistence. He also scored poorly on a test of design fluency, performing 4.5 SD below a mean performance. He performed adequately on the Wisconsin Card Sorting Test without failing any categories, and he performed at a mean level for the Trail Making and Stroop Tasks. The patient showed no insight into his performance during testing, assessing his performance on every test as above average. (Test results are given in terms of SDs from a mean population score. Readers are reminded that 97% of the population scored lie within 2 SDs from the mean. Therefore, a score that is either more than or less than 2 SDs from the mean puts the patient in the top or bottom 1.5% of the population, respectively.)

S.C. had a normal electroencephalogram. However, a magnetic resonance imaging scan (Fig. 1) showed cortical atrophy of the frontal lobes bilaterally but more marked on the right side in addition to moderate hydrocephaly. A brain single-photon emission computed tomography scan (Fig. 2) showed decreased blood flow to the frontal lobes, again with vastly reduced flow to the right side. These imaging studies corroborated neuropsychological and clinical impressions of a diagnosis of FTD.

Discussion

Many elements of S.C.'s case are typical of those observed for patients with FTD. Often it is the patient's family who seek the initial appointment. The story they tell is characteristically one of marked changes in lifestyle, leading to a series of very poor decisions or even several minor traffic accidents. The total disruption this causes in their daily lives is in marked contrast to a preserved orientation, normal mood, and good interpersonal rapport that belies the extent of their deficits. The subtle changes observed in the early stages of the disease along with a lack of conspicuous cognitive defects means that there is usually a marked delay between onset and diagnosis.9 This delay can become extended due to an unremarkable physical examination, including a lack of neurological abnormalities, and normal basic procedures; for example, the electroencephalogram is usually normal even when clinically evident dementia is present.4 Nevertheless, a distinct clinical picture can be drawn from the patient's history such as the lack of empathy, self-centeredness, and a decreased concern about friends and family, personal grooming, and appearance.10 Dietary habits and eating behaviors may also be altered to include hyperorality, excessive smoking or alcohol consumption, or a fixation preference for a certain type of food, such as sweets.11 Hypersexuality and sexual disinhibition can also occur,12 which can manifest itself in the form of a new found interest in pornography and excessive masturbation.

Brun et al.13 refined the clinical diagnostic features of FTD in 1994 and a consensus further updated these in 1998.14 These criteria were based upon initial reports of the disease emerging from Sweden and Manchester and published in the late 1980s and early 1990s.6,15,16 Diagnosis is made clinically by mode of presentation, neuroimaging procedures, and eventually confirmed at autopsy.10,17

Several screening and diagnostic tests have been developed, but no single test is considered the standard.18 The Mini-Mental State Examination is one of the most widely used bedside tests for mental status evaluation.19 However, it has its limitations, such as insensitivity to the frontal deficits found in early FTD and the inability to differentiate the various dementia subtypes.20

Some patients with FTD perform normally on batteries of tests designed to specifically test frontal lobe function. There have been several postulated reasons for this. Neary et al.6 suggested that the patients have a strategic failure to use memory effectively and that none of the tests we currently use require both memory and planning skills. Others have argued that frontal tests used at the moment are not "reality based" and that they require planning and executive function in a structured and rule-based setting. They argue that it is in real life unstructured situations like decision making related to financial planning that these patients fail because of inadequate foresight.21 More recent research has tried to address these issues. Bechara et al.22 designed a card game with an element of risk to it. In the game, a steady, nonrisk-taking strategy allows a gradual accumulation of points and offers the best chance of winning. Normal controls quickly realize this and perform very well on the task. Patients with frontal lobe damage, however, perform poorly by making risky decisions to try and make large short-term gains.

The changes characteristic of FTD have important effects on the ability of the sufferer to manage their affairs and their job-related duties. The inability to appreciate the consequences of their actions and to plan into the future, in combination with a total lack of insight regarding the changes in their behavior, eventually results in the patient leading a self-destructive lifestyle. The delay in diagnosis allows for destruction of their reputation and their financial stability, often along with their family life. Organizations, including the military, need to be more aware of the clinical effects of this disease to recognize and make allowances for the sufferers.

Conclusion

S.C. presented as a typical case of FTD. This disease, however, is still poorly recognized among the nonmedical public. The lack of conspicuous neurological changes in the early stages, in addition to the lack of a definitive screening instrument, causes frequent errors in diagnosis with possible differential diagnoses of personality disorder, hypomania, anxiety disorder, depression, or even alcoholism, depending on how the patient's behavioral disintegration and lack of judgment manifests itself. As this case demonstrates, the disease can have far-reaching ramifications for the lives of the patient and his family, and the diagnosis should always be considered in cases of erratic and unexplainable "out of character" behavior.

Acknowledgments We thank David Hermosillo Romo, PhD, for the neuropsychological testing.

References

1. Gustafson L: Frontal lobe degeneration of non-Alzheimer type II: clinical picture and differential diagnosis. Arch Gerontol Geriatr 1987; 6: 209-23.

2. Jagust WJ, Reed Br, Scab JP, Krarner JH, Budinger TF: Clinical-physiologic correlates of Alzheimer's disease and frontal lobe dementia. Am J Physiol Imag 1989; 4: 89-96.

3. Pachana NA, Boone KB, Miller BL, Cummings JL, Berman N: Comparison of neuropsychological functioning in Alzheimer's disease and frontotemporal dementia. J Int Neuropsychol Soc 1996; 2: 505-10.

4. Neary D, Snowden JS, Mann DM: Classification and description of frontofemporal dementias. Ann NY Acad Sci 2000; 920: 46-51.

5. Gustafson L: Clinical picture of frontal lobe degeneration of non-Alzhcimer type. Dementia 1993; 4: 143-8.

6. Neary D, Snowden JS, Northen B, Goulding PJ: Dementia of frontal lobe type. J Neurol Neurosurg Psychiatry 1988; 51: 353-61.

7. Snowden JS, Neary D, Mann DMA: Fronfo-Temporal Isobar Degeneration: Fronto-Temporal Dementia, Progressive Aphasia, Semantic Dementia. New York, Churchill Livingstone, 1996.

8. Neary D, Snowden JS, Gustafson L, Passant U, Stuss D, Black S, et al: Frontotemporal lobar degeneration: a consensus on clinical diagnostic criteria. Neurology 1988; 51: 1546-54.

9. Gregory CA, Serra-Mestres J, Hodges JR: Early diagnosis of the frontal variant of frontotemporal dementia: how sensitive are standard neuroimaging and neuropsychologic tests? Neuropsychiatry Neuropsychol Behav Neurol 1999; 12: 128-35.

10. Rosen HJ, Lengenfelder J, Miller B: Frontotemporal dementia. Neurol Clin 2000; 18: 979-92.

11. Brun A, Gustafson L: Clinical and pathological aspects of frontotemporal deinentia. In: The Human Frontal Lobes, pp 349-69. Edited by Miller BL, Cummings JL. New York, The Guilford Press, 1999.

12. Miller BL, Darby AL, Swartz JR, Yener GG, Mena I: Dielary changes, compulsions and sexual behavior in frontotemporal degeneration. Dementia 1995; 6: 195-9.

13. Brun A, Englund B, Gustafson L: Clinical and neuropathological criteria for frontotemporal dementia. J Neurol Neurosurg Psychiatry 1994; 57: 416-8.

14. Neary D, Snowden JS, Gustafson L, et al: Frontotemporal lobar degeneration: a consensus on clinical diagnostic criteria. Neurology 1998; 51: 1546-54.

15. Brun A: Frontal lobe degeneration of non-Alzheimer type: I neuropathology. Arch Gerontol Geriatr 1987; 6: 193-208.

16. Rossor MN (editor): Unusual Dementias, pp 477-689. London, Bailliere Tindall, 1992.

17. Kitagaki H, Mori E, Yamaji S, Ishii K, Hirono N, Kobashi S, et al: Frontotemporal dementia and Alzheimer disease: evaluation of cortical atrophy with automated hemispheric surface display generated with MR images. Radiology 1998; 208: 431-9.

18. Gifford DR, Cummings JL: Evaluating dementia screening tests: methodologic standards to rate their performance. Neurology 1999; 52: 224-7. 19. Tombaugh TN, McIntyre NJ: The mini-mental state examination: a comprehensive review. J Am Geriatr Soc 1992; 40: 922-935.

20. Gregory CA, Orrell M, Sahakian B, Hodges JR: Can frontotemporal dementia and Alzheimer's disease be differentiated using a battery of test? Int J Geriatr Psychiatry 1997; 12: 375-83.

21. Goel V, Grafman J, Tajik J, Gana S, Danto D: A study of the performance of patients with frontal lobe lesions in a financial planning task. Brain 1997; 120: 1805-22.

22. Bechara A, Damasio H, Tranel D, Damasio AR: Deciding advantageously before knowing the advantageous strategy. Science 1997; 275: 1293-5.

Guarantor: Raymond Faber, MD

Contributors: Victoria M. Hill, PhD*[dagger]; Billy J. Kim, BA*[dagger]; Raymond Faber, MD*[dagger]

* Psychiatry Service, Audie L. Murphy Memorial Veterans Administration Hospital, 7400 Merton Minter, San Antonio, TX 78229.

[dagger] University of Texas Health Science Center at San Antonio, San Antonio, TX 78229.

This manuscript was received for review in May 2002. The revised manuscript was accepted for publication in July 2002.

Reprint & Copyright (C) by Association of Military Surgeons of U.S., 2003.

Copyright Association of Military Surgeons of the United States Apr 2003
Provided by ProQuest Information and Learning Company. All rights Reserved