1. Chapter 6 Cause of Disease Lecturer: QU Hongyan

2. Brief introduction The cause of disease, refers to the factors that damage the relative equilibrium and result in disease. The etiology, an important component of the theoretical system of traditional Chinese medicine, studies the concept of various pathogenic factors, their formation, nature, pathogenic characteristics and the clinical manifestations of the disease caused by them.

3. others Endogenous pathogenic factors Pathogenic factors Exogenous pathogenic factors Pathological products

4. Methods to seek the cause of disease seeking the cause by syndrome differentiation TCM studies the cause of a disease, by understanding objective conditions that may become pathogenic factors according to the manifestations of the disease and through analysis of symptoms and signs of disease to infer its cause A characteristic of etiology in TCM

5. Exogenous pathogenic factors  Exogenous pathogenic factors---refer to the pathogenic factors which originate from the nature and invade the body from the body surface, or through the mouth and nose, causing exogenous disease. Six excesses Pestilential qi

6. Six excesses

7. Basic concept Six qi ： a collective term for six normal climate changes in nature including wind, cold, summer- heat, dampness, dryness and heat (fire). Six excesses ： a collective term for six exogenous pathogens including pathogenic wind, pathogenic cold, pathogenic summer-heat, pathogenic dampness, pathogenic dryness and pathogenic heat (fire).

8. UUnder the following conditions, six qi will turn into six excesses: six qi changes sharply, which goes beyond the normal adaptive ability ； body resistance becomes weak due to deficiency of healthy qi. Climatic changes （ six qi ） Healthy qi Six excesses Fall ill Healthy Six qi

9. Common pathogenic characteristics of six excesses  1 ． Exogenousness ： the six excesses usually invade the body through the body surface, the mouth and nose.  2 ． Seasonality ： diseases caused by the six excesses are often characteristic of distinct seasonality. In spring there are more wind diseases; dryness disease more in autumn

10. Common pathogenic characteristics of six excesses  3 3 ． Regionality ： Diseases caused by the six excesses are often connected with the environments and regions where people live and work.  4 4 ． Combination ： each of the six excesses can cause disease either alone or in combination with another. e.g. wind-heat cold wind-cold-dampness arthralgia

11. Common pathogenic characteristics of six excesses  5 ． Transformability ： Under certain conditions, the natures of diseases caused by six excesses can transform into one another. e.g. Wind-cold syndrome of exterior may turn into interior heat syndrome.

12. Wind pathogen  All exogenous pathogenic factors characteristic of lightness, rising, and opening-dispersing and migrating are called wind pathogen.

13.  Wind pertains to yang and is characteristic of lightness, rising and opening-dispersing and tends to attack yang location  Characteristic of wind being mobile and rapid changeable  Characteristic of wind being mobile  Wind being primary pathogen Natures and characteristics

14. Cold pathogen  All exogenous pathogenic factors characteristic of cold, coagulation and contraction are called cold pathogen.  Cold is prevalent in winter so there are more diseases caused by cold in this season. Diseases caused by cold can also be seen in other seasons.

15.  Cold pertains to yin and is apt to attack yang qi  Cold having property of coagulation and stagnation  Cold having property of contraction Natures and characteristics

16. Dampness pathogen All exogenous pathogenic factors characteristic of heavy turbidity, stickiness and stagnation and downward are called dampness pathogen.  Dampness is the dominant qi in late-summer or in the intersection of summer and autumn, it is the dampest in the year because there is steaming damp-heat and vaporizing water.  In addition, diseases caused by dampness can also result from swimming and drenching, living in wet and damp places and working in the water.

17.  Dampness is a yin pathogen and apt to hamper qi movement and damage yang qi  Characteristic of dampness being heavy and turbid  Characteristic of dampness being sticky and stagnant  Characteristic of dampness being descending and apt to attack yin locations Natures and characteristics

18. Summer-heat pathogen During the time from summer solstice to autumn begins, the exogenous pathogenic factors characteristic of scorching-hot, ascending and dispersive, mixed with dampness are called pathogenic summer-heat.  Summer-heat is the dominant qi in summer and transformed from fire-heat qi. It is only seen in summer, which is characterized by an apparent seasonality. So summer-heat is a pure exogenous evil and attacks the body usually not from the interior, but the exterior.

19.  Summer-heat pertains to yang and is characteristic of scorching-hot  Characteristic of summer-heat being ascending and dispersive, impairment of fluids and exhaustion of qi  Summer-heat being likely to be mixed with dampness Natures and characteristics

20. Dryness pathogen All exogenous pathogenic factors characteristic of dryness and astringency are called dryness pathogen.  Dryness, the dominant qi in autumn marked by depurating, descending, astringency and dryness, can be seen in four seasons of the year.

21.  Characteristic of dryness being dry and puckery and apt to impair fluids  Dryness likely to injure lung Natures and characteristics The lung is a tender viscus. It is externally connected with skin and hair, opens into the nose and aversion to dryness

22. Fire (heat) pathogen All exogenous pathogenic factors characteristic of torridity and flaming up are called fire (heat) pathogen.  Fire (heat) blooms in summer but is not so seasonal as summer-heat and it is no affected by seasons and climates. therefore fire diseases are seen in four seasons.

23.  Fire (heat) is a yang pathogen which characteristic being flaring up  Fire (heat) being likely to disturb heart-mind  Fire (heat) being likely to consume body fluids and exhaust qi  Fire (heat) being likely to cause convulsion and bleeding  Fire (heat) being likely to cause sores and abscesses Natures and characteristics

24. Pestilential qi Concept  It is an exogenous pathogenic factor which is strongly infective, and it can cause diseases through air, food, bites by insects and animals, dermal contact, etc. Pathogenic characteristics of pestilential qi  Strong infective and epidemic  Acute onset and severe condition  Diseases vary with pestilential qi but symptoms are similar

25. Internal injury pathogenic factors  Internal injury cause of disease are those generated internally, which can directly lead to disorders of qi and blood as well as impairment of visecra. Internal injury due to seven emotions Improper diet Overstrain and overease

26. Internal injury due to seven emotions

27. Basic concept Seven emotions ： refer to seven emotional activities including joy, anger, worry, anxiety, sadness, fear and fright. Internal injury due to seven emotions ： when the emotional stimulations are too abrupt, violent, and prolonged and beyond one’s adaptability or when there is diminished adaptability due to imbalanced yin-yang, qi and blood of viscera, can they turn into pathogenic factors.

28. Emotional stimulus Healthy qi Fall ill Be healthy Internal Injury due To seven emotions Seven emotions

29. Relationship between seven emotions and visceral essential qi 五脏 liver heart spleen lung kidney essence Qi 情志 anger joy anxiety sadness fear store transform generate impairhurt injure

30. Pathogenic characteristics IImpairing the viscera AAffecting the visceral qi movement TTending to cause emotional diseases AAffecting the sequelae of diseases Rage leading to qi ascending, excessive joy leading to qi loose Fear leading to qi sinking Fright leading to qi turbulance.

31. Irregularity of diet

32. Unhygienic diet Food preference Improper diet

33. Conscious control of eating Obstinate Psychological diseases Anorexia, lusterless Complexion, palpitations Short breath, general lassitude Overeating impairs the spleen and stomach Gastric and abdominal fullness and distention eruction, acid regurgitation anorexia, vomiting and diarrhea

34. Unhygienic diet  This refers to eating unclean food, such as taking food gone bad, polluted by pestilent evils, parasites or mistaken intake of poisonous food. Gastric and abdominal pain, nausea and vomiting, diarrhea with borborygmus, or dysentery Take in the food that has gone bad Take in the food contaminated by epidemic toxin Infectious diseases

35. Diet predilection  This refers to the phenomenon that diseases can start due to the liking of foods with certain taste or specially eating certain foods, including predilection for cold or hot food, or predilection for one of the five tastes or predilection for alcohol. Predilection for cold or heat Predilection for the five tastes Predilection for alcohol Predilection for one type of food

36. Predilection for cold or heat Abdominal pain diarrhea Excessive intake of cold food Partiality to spicy-hot food Thirst, halitosis, abdominal distention pain, constipation etc Impair the yang qi of spleen and stomach Cold-dampness is produced internally Impair the stomach yin

37. Predilection for the five tastes Long term of preferring food with a certain taste can cause the preponderance of its corresponding viscera, thus causing disharmony among viscera. acidbittersweetpungentsalt liverheartspleenlungkidney e.g.

38. Predilection for one type of food  It refers to a long period of special taking of some foods or not taking some foods or lack of certain food. Obesity, vertigo stroke, consumptive thirst and so on Long time of excessive ingesting rich food Long time for lacking of some nutrients Night blindness goiter and tumor Production of Phlegm and transformation of heat

39. Imbalance between work and rest

40. It refers to long time of overstrain or indulgence in easy life. Normal work can help build the body and improve health Proper rest can remove fatigue and help recover strength

41. overstrain Overease/ indulgence in easy life overexcertion Mental overstrains Sexual overstrains

42. Overexertion It refers to prolonged engagement of physical labor or exercise, beyond a normal limit. Reluctant to speak fatigue and tiredness sweating, dyspnea etc Consumption of qi Impairment of the body Injure muscles, tendons and bones Impair the functions of viscera and cause asthenia of visceral qi

43. Mental overstrains Heart throb, amnesia, insomnia dreaminess, poor appetite, abdominal distention and diarrhea, etc. mental overstrains Impair the heart and the spleen and consume qi and blood It refers to long time of attention or pensiveness.

44. Sexual overstrains Aching and weakness in the waistand knees, vertigo, tinnitus, dispiritedness, or spermatorrhea prospermia, and impotence in men and dysmenorrhea leukorrhea or sterility in women sexual overstrains Consume essence In the kidney It refers to excessive sexual activities, masturbation, or early pregnancy or giving many births.

45. Indulgence in easy life Reduced appetite, abdominal distention, limb heaviness, muscular flaccidity, oppression in chest and shortness of breath Absence of physical work sports Qi stagnation of the spleen and stomach

46. Pathological products  Phlegm-fluid retention  Stagnant blood  calculus