UCLA

Objectives

To evaluate coronary artery calcification (CAC) on routine CT chest in hospitalised HIV patients and to assess individual risk factors.

Methods

Routine CT chests, May 2010-November 2015, of 143 hospitalised HIV-positive patients were reviewed for qualitative assessment of calcification in major coronary arteries by two radiologists. Presence, location and burden of calcification were evaluated on 3 mm axial images of CT chest. Cardiovascular risk factors and HIV lab parameters such as CD4 count, viral load and duration, and status of antiretroviral treatment were collected. Statistical analysis including multivariate logistic regression was performed.

Results

Forty-one patients (28.7%) showed CAC, left anterior descending (n = 38, 92.7%), circumflex (n = 18, 43.9%) and Right Coronary Artery (n = 13, 31.7%); mostly mild CAC burden and mostly proximal left coronary arteries with excellent interobserver and intraobserver agreements (K = 0.9, and 1). Age of CAC+ group (53.9 years) was significantly higher than CAC- group (43.4, p < 0.001, minimum age of CAC+, 27 years). No significant difference between two groups in sex, ethnicity and risk factors and HAART status. CAC+ group showed significantly longer HIV duration (12.3 years vs 8.6, p < 0.0344) and higher CD4 cell counts (mean = 355.9 vs 175.3, p = 0.0053) and significantly lower viral load (76 vs 414K, p = 0.02) than CAC- group. On multivariate logistic regression, age, HIV duration and CD4 were significantly associated with CAC+ (p-values < .05).

Conclusions

One-third of hospitalised HIV patients showed subclinical CAC on CT chest. HIV duration and age of patients were independent risk factors for developing CAC. Higher CD4 cell count was strongly associated with CAC+.

Advances in knowledge

Routine CT chest with or without contrast performed for non-cardiac indications is helpful in identification of subclinical CAC in HIV patients and radiologists should be encouraged to report CAC.CAC is seen in younger age group in HIV, and awareness of this finding on routine CT chest would help guiding clinicians to assess risk stratification for primary prevention of ischemic heart disease in this population at an earlier stage when compared to normal population.Duration of HIV infection and age of patients were independent risk factors for developing CAC in our study and CD4 count was strongly associated with presence of CAC.