title: The importance of comorbidity in HIV-infected patients over 55: a retrospective case-control study.
abstract: OBJECTIVE
  To study the impact of comorbidity on the course of HIV disease in older patients as compared to a matched cohort of younger patients.
  
  
  METHODS
  In a retrospective case-control study, we compared 43 HIV-infected patients > 55 years old to a randomly selected cohort of 86 patients < 45 years old, matched by date of HIV diagnosis. We collected data on non-HIV-related morbidity (as assessed by the Charlson comorbidity index), initiator of HIV testing, HIV stage at time of HIV diagnosis (TOHD), AIDS defining diagnoses, AIDS-related illnesses (ARI), observed AIDS-free interval, survival, and frequency of HIV-related and unrelated hospitalizations.
  
  
  RESULTS
  The older cohort was more likely to have had HIV testing initiated by a health care provider (36 of 36 versus 50 of 66, P = 0.003), and to have acquired HIV from a transfusion (5 of 43 versus 0 of 86, P = 0.001), had lower CD4 cell counts at TOHD (205 versus 429, P = 0.02), a shorter observed AIDS-free interval (24.0 versus 52.8 months, P = 0.0002) and a shorter survival (28.2 versus 58.9 months, P = 0.0002). The older cohort had more HIV-related (13.4 versus 9.2 per 100 patient-months, P = 0.024) and non-HIV-related hospitalizations (12.9 versus 8.1 per 100 patient-months, P = 0.0001). The comorbidity index was significantly higher in the older cohort (0.907 versus 0.198, P = 0.0001) and was a strong predictor of mortality, independent of age group (risk ratio = 1.38 per comorbidity point, P = 0.0003).
  
  
  CONCLUSIONS
  Older HIV-infected patients presented with more advanced disease, which may have been due to lack of HIV awareness in this population. Older patients had a shorter observed AIDS-free interval and shorter survival. In addition, they had more HIV- and non-HIV-related comorbidity. The more rapid course and decreased survival in the elderly may be related to the increase in comorbidity.
authors.affiliation: University of Texas Southwestern Medical Center, Division of Infectious Diseases, Dallas 75235-9113, USA.
authors.forename: D J
authors.initials: DJ
authors.lastname: Skiest
authors.forename: E
authors.initials: E
authors.lastname: Rubinstien
authors.forename: N
authors.initials: N
authors.lastname: Carley
authors.forename: L
authors.initials: L
authors.lastname: Gioiella
authors.forename: R
authors.initials: R
authors.lastname: Lyons
mesh_terms: D017088:AIDS-Related Opportunistic Infections / Q000401:mortality; D000328:Adult; D000367:Age Factors; D000368:Aged; D016022:Case-Control Studies; D016009:Chi-Square Distribution; D015897:Comorbidity; D018450:Disease Progression; D005260:Female; D015658:HIV Infections / Q000150:complications* / Q000401:mortality; D006760:Hospitalization; D006801:Humans; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D011237:Predictive Value of Tests; D012189:Retrospective Studies; D012306:Risk; D016019:Survival Analysis