title: [A retrospective clinical study of chronic high altitude disease complicated by acute exacerbation in high altitude environment].
abstract: OBJECTIVE
  To study chronic high altitude disease (CHAD) with concurrent acute high altitude disease (AHAD) in regions of high altitude.
  
  
  METHODS
  18,090 inpatients from Feb. 1956 to Dec. 1995 conforming to a screening standard were observed in a hospital located at altitude 3658 m. 1,028 inpatients suffering from CHAD when hospitalized were collected as a study group. 17,020 inpatients suffering from non-HAD when first hospitalized served as a control group. The morbidity rate of AHAD in these two groups in a follow-up period of 1 - 20 years was analyzed.
  
  
  RESULTS
  (1) AHAD morbidity rate was increasing with prolongation of observation time in the control group, but it was not so in the study group. Annual and accumulative morbidity of AHAD in the study group was obviously higher than that in the control group (P < 0.005, OR = 5.03, RR = 4.33). (2) The morbidity rates of three types of AHAD aside from high altitude pulmonary edema (HAPE) of high altitude hypertension (HAH) group and high altitude cerebral edema (HACE) of high altitude heart disease (HAHD) group was obviously higher in the study group than in the control (P < 0.05 - 0.005). AHAD morbidity rate in HAHD group and Monge's disease was 23.5% and 22.0% (OR = 7.33 - 6.71, RR = 5.86 - 5.47). (3) AHAD morbidity rate in HAHD group and Monge's disease group was obviously higher than that in the control, constituting mainly a high morbidity of mild acute high altitude disease.
  
  
  CONCLUSIONS
  The risk of AHAD increases about 5-fold in CHAD patients than in the multitude of high altitude acclimatization, being most evident in HAHD and Monge's disease.
authors.affiliation: The Chengdu Military Tibet General Hospital, Lhasa 850003, China.
authors.forename: Yue
authors.initials: Y
authors.lastname: Huang
authors.forename: Su-zhi
authors.initials: SZ
authors.lastname: Li
authors.forename: Ling-chang
authors.initials: LC
authors.lastname: Guo
authors.forename: Xue-kai
authors.initials: XK
authors.lastname: Wang
authors.forename: Si-yuan
authors.initials: SY
authors.lastname: Jiang
mesh_terms: D000208:Acute Disease; D000293:Adolescent; D000328:Adult; D000368:Aged; D000531:Altitude; D000532:Altitude Sickness / Q000150:complications*; D002648:Child; D002675:Child, Preschool; D002908:Chronic Disease; D004777:Environment; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies