title: The association of CD4+ T-cell counts and cardiovascular risk in treated HIV disease.
abstract: OBJECTIVE
  HIV-infected individuals are at high risk of developing cardiovascular disease. Whether earlier initiation of HIV therapy at higher CD4 cell counts has any effect on cardiovascular risk as assessed by endothelial function is unknown.
  
  
  METHODS
  Cross-sectional study of 74 antiretroviral-treated men with undetectable plasma HIV RNA levels.
  
  
  METHODS
  Participants underwent noninvasive assessment of endothelial function using brachial artery flow-mediated dilation (FMD). The association of nadir and current CD4 T-cell count with FMD was assessed using multivariable linear regression.
  
  
  RESULTS
  The median age was 47 years [interquartile range (IQR) 42-55], median current CD4 T-cell count was 659 cells/μl (IQR 542-845), and nadir CD4 cell count was 314 cells/μl (IQR 150-490). Twenty-eight percent had hypertension, and 32% hyperlipidemia. Nadir CD4 T-cell count less than 350 cells/μl was associated with lower FMD in age-adjusted and race-adjusted analyses and remained an independent predictor of FMD after adjustment for cardiovascular risk factors (hypertension, diabetes, smoking, hyperlipidemia) and HIV-related characteristics (HIV duration, HAART duration). After multivariable adjustment, individuals with nadir CD4 T-cell count less than 350 cells/μl had a 1.22% lower FMD compared with those with higher T-cell counts [95% confidence interval (CI) -2.20 to -0.19, P=0.02]. Proximal CD4 T-cell count showed little association with FMD.
  
  
  CONCLUSIONS
  Among treated HIV-infected individuals, nadir CD4 T-cell count less than 350 cells/μl is independently associated with lower FMD, suggesting that delayed therapy results in sustained harm to endothelial function. Our data support future prospective studies evaluating cardiovascular effects of HAART initiation at higher CD4 cell counts.
authors.affiliation: Division of Cardiology, Massachusetts General Hospital, Boston, Massachusetts, USA.
authors.forename: Jennifer E
authors.initials: JE
authors.lastname: Ho
authors.forename: Rebecca
authors.initials: R
authors.lastname: Scherzer
authors.forename: Frederick M
authors.initials: FM
authors.lastname: Hecht
authors.forename: Kristinalisa
authors.initials: K
authors.lastname: Maka
authors.forename: Van
authors.initials: V
authors.lastname: Selby
authors.forename: Jeffrey N
authors.initials: JN
authors.lastname: Martin
authors.forename: Peter
authors.initials: P
authors.lastname: Ganz
authors.forename: Steven G
authors.initials: SG
authors.lastname: Deeks
authors.forename: Priscilla Y
authors.initials: PY
authors.lastname: Hsue
mesh_terms: D000328:Adult; D023241:Antiretroviral Therapy, Highly Active; D001916:Brachial Artery / Q000000981:diagnostic imaging / Q000503:physiopathology*; D018791:CD4 Lymphocyte Count; D015496:CD4-Positive T-Lymphocytes / Q000502:physiology*; D002318:Cardiovascular Diseases / Q000150:complications / Q000503:physiopathology*; D003430:Cross-Sectional Studies; D004727:Endothelium / Q000503:physiopathology; D015658:HIV Infections / Q000150:complications / Q000188:drug therapy / Q000503:physiopathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D012367:RNA, Viral / Q000097:blood; D012307:Risk Factors; D014463:Ultrasonography; D019562:Viral Load
chemical_list: D012367:RNA, Viral