Comorbidity

Comorbidity is a common phenomenon. In English it is called comorbidity; some translate it as "co-illness" or "concurrent disease," but in Chinese the term that best captures the English word is gongbing (comorbidity). It means the simultaneous presence of two or more diseases. For example, a cancer patient may also suffer from major depressive disorder, schizophrenia, diabetes, or hypertension; a patient with borderline personality disorder may also have post-traumatic stress syndrome or depression.

For patients who have several diseases at once, relief of one usually eases the suffering of the others. If a cancer patient receives proper treatment and the cancer goes into remission, his depression may lighten and his blood pressure may fall. Generally, for comorbid patients the ideal approach is to treat several diseases simultaneously, which maximally improves quality of life.

Treating stubborn diseases such as cancer and depression is therefore no easy matter. Only yesterday, a PhD in Chinese medicine consulted me about treating cancer. I told him there is no secret trick for treating such diseases; one can only raise one's own comprehensive level. The tumor patients I have seen over the years are truly walking complexes of disease, usually with several comorbid conditions. When they turn to Chinese medicine for help, we must approach them from many angles, helping to relieve both their physical and spiritual suffering.

The Tang-dynasty physician Sun Simiao, revered as the King of Medicine, wrote a famous essay called "On the Absolute Sincerity of the Great Physician." He also wrote one called "On the Learning and Practice of the Great Physician," in which he says: "Whoever wishes to become a great physician must be thoroughly familiar with the Suwen, the Jiayi [Zhenjing], the Huangdi Zhenjing, the Mingtang Liuzhu, the twelve meridians, the three regions and nine indicators of pulse examination, the five zang and six fu, the exterior-interregion acupoints, the bencao and herb pairs, and the classic prescriptions of Zhang Zhongjing, Wang Shuhe, Ruan Henan, Fan Dongyang, Zhang Miao, Jin Shao, and others. He must also subtly understand yin-yang and destiny, the various schools of physiognomy, turtle-shell divination, and the Liu Ren method of the Zhouyi, and must be proficient in all of these; only then can he become a great physician. Otherwise, he is like a man walking at night without eyes, forever stumbling. Next, he must read these prescriptions repeatedly, ponder their subtle principles, and diligently study them; only then can he speak of the Way of medicine. He must also read widely—and why? Without the Five Classics he will not know the way of benevolence and righteousness; without the Three Histories he will not know the affairs of antiquity and the present; without the philosophers he will not, on seeing events, quietly retain their meaning; without the Buddhist canon he will not know the virtues of loving-kindness, compassion, sympathetic joy, and equanimity; without Zhuang[zi] and Lao[zi] he will not be able to abide in truth and embody the natural workings of things, and so auspicious and inauspicious prohibitions will rise up at every step. As for the waxing and waning of the five phases and the astronomy of the seven luminaries, these too must be explored. If he can study all of them, then in the Way of medicine there will be no obstruction, and he will reach perfection."

From this essay we can see that Sun Simiao believed a physician who would be a great physician must study almost every kind of learning, reaching the state of "supreme clarity" described in the Buddhist sutras. The sutra describes supreme clarity this way: "When the defilements of the mind are utterly ended, pure and without blemish, this is called supreme clarity. Before heaven and earth existed, down to the present day, in all the ten directions, there is nothing not seen, nothing not known, nothing not heard; having attained all wisdom, one may be called enlightened."

The times are advancing, and human knowledge is being renewed ever faster. When we look again at the standards of the King of Medicine Sun Simiao, they are already outdated. A physician today, whether Chinese or Western, who wishes to reach the standard of a great physician must at the very least be proficient in biology, chemistry, modern medicine, Chinese medicine, psychology, psychiatry, and even religion, philosophy, sociology, history—every discipline bound up with human physical and mental health. The amount a physician must learn is the greatest of any profession. The ancients said that if one cannot be a great minister, one should be a great physician—but being a great physician is hard! At the very least, I myself am still far from being one.

The reason we must learn so much is that every patient we face may present with comorbidity. Even if we cannot relieve or remove all their suffering, we must at least be able to recognize their diseases. To this day, even in the countries with the best medical conditions, about half of diagnoses are wrong. Many patients with chronic diseases are misdiagnosed for years or over a decade, and some are misdiagnosed their whole lives. If diagnosis cannot be accurate, treatment is even less likely to work. This has made the lives of many patients outright tragedies.

Comorbidity often creates the illusion that one disease is caused by another. For example, many cancer patients suspect that they got cancer because of long-term melancholy; some even wonder whether a "cancer-prone personality" exists.

At present there are no data to confirm such an idea. From a biological standpoint, most psychiatric or psychological illnesses have a physiological basis in damage to some region of the brain, whereas the biological basis of cancer lies chiefly in overexpression of proto-oncogenes and inactivation of tumor suppressor genes; there is no necessary causal link between the two. If there is any resemblance, it may simply be that both are caused by the interplay of inborn genes and acquired environment.