Helmchen, H., Baltes, M. M., Geiselmann, B., Kanowski, S., Linden, M., Reischies, F. M., Wagner, M., Wernicke, T., & Wilms, H.-U. (1999). Psychiatric illness in old age. In P. B. Baltes & K. U. Mayer (Eds.), The Berlin Aging Study: Aging from 70 to 100 (pp. 167-196). Cambridge: Cambridge University Press.
In this chapter, we report
empirical findings from the Berlin Aging Study (BASE) on the types and
frequencies of psychiatric illnesses in old age, their somatic and social
predictors, and their consequences.
Nearly half (44%) of the West Berliners aged 70 and above had no psychiatric disorders, whereas less than a quarter (24%) was clearly psychiatrically ill (specified DSM-III-R1 diagnoses). The remaining third consisted of carriers of psychopathological symptoms without illness value (16%) and of psychiatric syndromes with illness value (17%). Because this last group (mainly affective disorders) differs from the psychiatrically healthy in indicators of health impairment (in prognosis and use of psychotropic drugs), despite not fulfilling the criteria of operationalized DSM-III-R diagnoses, we speak of "subdiagnostic psychiatric morbidity." In further analyses we tried to determine the thresholds defining gradations from mental health to subdiagnostic psychiatric morbidity. Thus, with the help of a consensus conference between internists and psychiatrists, which was specifically developed for the purpose of BASE, we have demonstrated that in the case of depression, scores on the Hamilton Depression Scale (HAMD) are half as great when cases that are probably of somatic origin are excluded.
The most frequent psychiatric illness in old age is dementia, affecting 14% of those aged 70 years and above. Recalculated for the population of over-65-year-olds, this corresponds to a prevalence of 6% (excluding mild forms). The number of dementia cases increases strongly with age. Whereas no cases were found in BASE at the age of 70, more than 40% of 90-year-olds were affected. Depressive illnesses are the second most frequent psychiatric diagnosis, affecting 9% of the elderly population. There is no clear relationship with age. On the level of diagnoses, there is no association between dementia and depression. On the syndromal level, however, one finds a positive correlation between mild cognitive disorders (Mini Mental State Examination [MMSE] score over 16) and depressivity (HAMD and Center for Epidemiologic Studies-Depression Scale [CES-D]). For severe cognitive disorders, this correlation is negative.
Persons with depressive illnesses or dementia have a higher rate of physical illnesses than the mentally healthy. It remains to be seen whether physical illnesses are the causes or consequences of mental illnesses. In terms of possible social risk factors, an important finding is that a lower level of education increases the likelihood of a dementia diagnosis. This is in agreement with other studies.
Mental illnesses differ with regard to their consequences for everyday functioning. With dementia, one observes a decrease in instrumental or practical activities, a doubling of sleep and rest phases, and a reduction of time spent outdoors. In contrast, depressive disorders rarely have similar effects. Therapeutic consequences of mental disorders also differ. About two thirds of older people take psychotropic drugs (defined broadly, including analgesics) and a quarter take strictly defined psychotropic drugs. More than two thirds of the psychotropic drug prescriptions can be regarded as appropriate. Overdosages were not observed. A comparatively low rate of overall prescriptions (i.e., including medication for somatic disorders) was found for persons with dementia while the rate of neuroleptics was actually increased. In the case of depressive illnesses, the general medication rate was relatively high. However, only few depressive elderly patients were treated specifically with antidepressive medication, which is suggestive of undermedication.
According to these BASE findings, it must be emphasized that older adults need careful differential diagnosis and treatment of mental disorders, because the form, course, and treatment are just as varied -- if not more, due to multimorbidity -- in old age as in younger years.