Mohammed T. Abou-Saleh

588 PRINCIPLES AND PRACTICE OF GERIATRIC PSYCHIATRYfor antisocial PD. The mean concordance rate for monozygotictwins for the disorder was double that of dizygotic twins (68% vs.33%). Adoption studies 9,10 have also found ‘‘temperamental’’factors to be a major determinant for antisocial PD. Familystudies find increased rates of substance abuse, antisocial PD andother psychopathology in first-degree relatives of felons, manywith the diagnosis of antisocial PD 11 .Schizotypal PD has been well examined from a geneticperspective and owes much of its appearance as a diagnosis tothat association. Schizotypal PD has a significant heritablerelationship to schizophrenia. Kendler et al. 12 were unable tofind an equivalent environmental association. Torgersen 13 confirmedthe genetic link between schizoid and paranoid features ofschizophrenia and schizotypal PD.The final disorder that has yielded studies on heritability isborderline PD. A credible familial association has been foundbetween borderline PD, affective disorders and other PD 14 .Previous associations between ‘‘borderline states’’ and theschizophrenic spectrum have been difficult to interpret becauseof differing definitions of ‘‘borderline states’’ and the relationshipsof these definitions to current DSM-IV criteria for borderline PD.Individuals with a history of impulsive or affective instability,which more closely fit present borderline PD criteria, may nothave a greater prevalence of schizophrenia in their relatives 14 .In summary, there is clear evidence of heritability for some PDbut much that remains unexamined. As Clarkin, Speilman andKlausner 15 note in their conceptual overview of PD in the elderly,the research on the relationship of genetic factors to PD is sparse,and speculations concerning the neurobiology of PD remainspremature. The remaining ‘‘nurture’’ factors also comprise asignificant component, but have yet to be clarified.Neurobiological studies have been very rare. EEG slow-waveactivity has been associated with antisocial PD. Borderlinepatients have a significantly higher percentage of marginal EEGabnormalities than controls 16 . They also show changes incerebrospinal 5-hydroxyindole-acetic acid (5-HIAA), a measureof serotonin activity that is correlated negatively with measures ofaggressivity. Finally, schizotypal and borderline PD have beenlinked with low platelet monoamine oxidase (MAO) activity 17,18 .Individuals with schizotypal PD may also show impaired smoothpursuit eye movement. 19,20 .ASSESSMENTAssessment of PD requires an examination of variables that maybe difficult to measure, especially in older adults. There are, forinstance, problems in obtaining a reliable diagnosis. Since all thestandardized instruments used to measure PD have beendeveloped for a younger population, these devices thereby requiremore administration time for older adults (since they have longerpersonal histories). Consequently, there is no ‘‘gold standard’’ ofdiagnosis for PD in older adults. Molinari et al. 21 studiedgeropsychiatric inpatients with depression, and found generaldiscordance between patient self-report, family informant ratings,social worker evaluations, and consensus case conferencecategorical diagnosis of PD. It appears that there are variedperceptions of an individual’s personality, all of which should betaken into account for a comprehensive evaluation of Axis IIpathology.From a clinical perspective, PD is quite common in medicalpractice, yet infrequently recognized. Mental health professionalsare loathe to diagnose PD, particularly in old age, due to concernsover pejorative bias, pessimistic belief in Axis II changes,managed care reimbursement biases, and focus on medical orAxis I pathology (particularly cognitive impairment) in old age.Often the PD patient presents with unrealistic expectations,complaints and demands, and an inappropriate interpersonalstance. Essential features of PD, regardless of age, will include:maladaptive behavior as a lifestyle; inflexibility in managinginterpersonal situations; multiple physical, social and interpersonalproblems; and externalization of these problems in theabsence of psychosis 22 . Yet these same features are sometimesaccepted, erroneously, as part of the aging process. In a geriatricsetting, somatic presentations of PD are common, which cancomplicate ‘‘teasing out’’ true co-morbid medical/cognitiveproblems from personality dysfunction. Patients with PDfrequently present with chief complaints of ‘‘bad nerves’’,sleeplessness, non-specific requests for help and pain syndromes.In addition, Axis I disorders can confound appropriate diagnosisand confuse the long-term picture. For example, evidence suggeststhat older depressives are significantly more likely to have lifetimepersonality dysfunction than controls 23,24 . Therefore, it behoovesthe clinician to ascertain whether a pattern of historicallymaladaptive personality traits exist in the older patient withdepression. Treatment of the depression may very well result in asymptom picture reflecting a baseline PD, rather than adepression in partial remission.EPIDEMIOLOGYSome early anecdotal reports suggested that personality characteristicsbecome uniformly less harsh with age 25,26 . Otherclinicians working with older adults believed that the ‘‘highenergy’’PDs (e.g. Cluster B) mellow, while the ‘‘low-energy’’ PDs(e.g. Cluster C) may be aggravated by the aging process 27–29 .DSM-IV 1 states that, ‘‘Some PDs tend to become less obvious orremit with age, whereas this appears to be less true for some othertypes’’ (p. 632). This statement underscores some of the morerecent empirical work in this area, and contrasts with the morebenign general appraisals of DSM-III 30 and DSM-III-R 31 , whichmerely note that PD becomes ‘‘less obvious’’ with age. Earlyresearch yielded wide variability in PD prevalence rates due toinadequate definitions of PD, non-standardized measures, anddifferent samples of older adults. With the introduction ofDSM-III and the development of instruments tied to DSM-IIIcriteria, some consistent findings have emerged. This section onepidemiology will therefore largely focus on studies usingstandardized measures, and will be divided into community,institutional, outpatient and depression studies.Community SettingsIn community settings, two studies 26,32 compared young and olderadults utilizing the Coolidge Axis II Inventory. Coolidge et al. 26 ,found a greater need for organization and more restricted affect inolder adults, while Segal et al. 32 found that older adults weresignificantly higher on obsessive–compulsive and schizoid PD, butlower on the antisocial, borderline, histrionic, narcissistic andparanoid scales. Ames and Molinari 33 used the StructuredInterview for Disorders of Personality scale (SIDP-R) anddetected a trend of less PD in older adults, with significantlyfewer older adults meeting the criteria for more than one PD.Cohen et al. 34 used the Structured Psychiatric Examination andfound that those over the age of 55 were less likely (6.6% vs.10.5%) to have PD, due to a three-fold decrease of Cluster B PDin older adults. These data documenting personality ‘‘mellowing’’in older adult community samples are in stark contrast to theresults of a more recent study by Segal et al. 35 , who found that ahigh number (63%) of very old (X=76.2 years) communitydwellingadults met PD criteria by self-report. However, this studywas potentially flawed by failure to take into account the cognitive