Psychiatric Disease in Relation to Physical Illness

So on the psychiatry side we see that these disorders are exceedingly common. More common than diseases like arthritis, diabetes, and asthma, with which we are all familiar. What is the public health significance of these mental disorders? As noted earlier, depression is significantly associated with lower socioeconomic status. But there is also a very important correlation with physical disease. This is what is called the clinical conundrum (Eastwood). This says that while psychiatric disorders, usually depression or anxiety, often present with physical complaints there is, indeed, a true excess of physical ailments and premature death among psychiatric patients. In other words, patients who are depressed may go to the doctor and say that they have an upset stomach or headache, and the doctor may take this at face value. He will attempt to evaluate the patient, by taking a history and carrying out an examination, and put the symptoms into some physical disease context. If this fails he may tell the patient that there is nothing wrong with him so the patient continues to have his psychiatric disorder, which the doctor fails to recognize. This is a terrible state of affairs, although too common, and leaves the patient depressed and/or anxious and not knowing what to do.

So it is important that the presentation of psychiatric illness is recognized for what it is. A patient may have an affective illness, anxiety, or depression, and present with so-called somatic symptoms; or may be hypochondriacal; or may have psychiatric symptoms as an overlay to preexisting physical disease. Elderly patients may suffer from delirium. This is a condition where the patient is temporarily confused, due to such causes as too much medication or infection. It can be seen that there is a complex intertwining of physical and mental illnesses in their presentations. Beyond that there is outcome. The clinical conundrum says that not only are the psychiatrically ill misdiagnosed but they actually carry more risk for physical diseases. This can be understood in terms of risk for certain physical diseases and/or risk of premature death. At one time certain diseases were labelled as being "psychosomatic." This was intended to mean that such diseases were specifically caused by "stress." These were diseases like peptic ulcer, diabetes, hypertension, and rheumatoid arthritis. This kind of simplistic thinking is now viewed as naive. All diseases are a complex mixture of genetic risk and environmental hazards. Epidemiology, by means of cross-sectional and longitudinal studies, has successfully examined the mind-body relationship. Early studies from mental hospitals, in a variety of countries, showed that patients had more diseases, such as tuberculosis, than might be expected. These could lead to premature death from so-called natural causes. In addition, these patients had more "unnatural" deaths from suicide. Community studies, which were carried out later, and were much more sophisticated, however, came up with the same results. An example is the Stirling County study, in Nova Scotia, Canada, which has followed a community sample since 1952 (Murphy et al.) The patients with depression, particularly males, carried a significantly greater risk of premature death, especially from heart disease. So not only do the mentally ill contract more physical diseases in general, but more specific diseases. Depression and vascular disease, for example, appear to be intimately and reciprocally related. Thus 20 percent of patients who have had a heart attack develop depression, as do 50 percent of patients who have had a stroke. This is the case after controlling for vascular risk factors. So depression may be an independent risk factor for vascular disease and vice-versa. One explanation for less depression being found in elderly persons is that the depressed have died in middle age from vascular disease. Clearly, with advancing age, and especially in great (very old) age, the relationship between mental and physical illness becomes more complicated. Everybody succumbs to physical disease prior to death, but not every elderly person has a mental illness. Curiously, those with Alzheimer's disease are frequently and, ironically, physically well. We do need to know more about depression. Women carry twice the burden of risk for depression as men, yet men get more heart disease and more often commit suicide. Life events, early life experiences, and being separated or divorced are important factors associated with depression. The Cross National Collaborative group study found that the prevalence of depression varies from country to country; that mood disorders are becoming more common and starting earlier in life; and that only about 15 percent get treated, even in the most advanced countries.