Page 297 - SAHCS HIVMed Journal Vol 20 No 1 2019

Page 4 of 6 Original Research

prevented and treated. In the cART era, more than 50% of
25
Source of the curve
AGE WF Reference line deaths of HIV-positive individuals in Europe and North
26
America are not because of AIDS. In highly resourced regions,
ROC curve cardiovascular disorders and hepatic disease, mainly because
1.0 of chronic co-infection with hepatitis B or C, are important
causes of morbidity and mortality among the HIV-infected.
The development of hepatic steatosis in mono-infected HIV
0.8
patients is common and in one report, the cumulative incidence
over a 4.9 year period was 24%. NAFLD is also associated
27
with idiopathic cirrhosis in HIV-infected patients, and cardiac
0.6
Sensi vity 0.4 disease and decreased survival in the general population. Its
28
early recognition – it is asymptomatic in the early stages – in
the HIV-infected is therefore a priority.
WC and BMI are widely used for the identification of
0.2
individuals with NAFLD. 29,30 Both metrics have limitations
because BMI does not take into account the specific
0 distribution between peripheral and central fat compartments.
0 0.2 0.4 0.6 0.8 1.0 WC is a better marker in that sense, but it also does not
31
1 - specificity reliably reflect the quantity of visceral fat tissue alone.
Waist-to-height ratio as a measurement of abdominal obesity
FIGURE 1: Results of the receiver operating characteristic analysis.
linked to age showed better sensitivity in the risk evaluation
than WC in different populations. The advantage of this
TABLE 3: The presence of steatosis in subgroups of patients (formed according
to the cut-off values of the visceral fat and age). indicator is probably because of neutralisation of the
Subgroups of patients Steatosis Total influence of the height, so it enables identification of fat
Absent Present concentration in relation only to age and no other body
N s.d. N s.d. measurements. All three anthropometric measurements
Group 1 (visceral fat < 31.98, age < 38.5) 27 2.9 0 -3.4 27 showed significant differences in our study population, being
Group 2 (visceral fat > 31.98, age < 38.5) 12 0.4 4 -0.4 16 higher in patients who developed steatosis than in those who
Group 3 (visceral fat < 31.98, age > 38.5) 9 0.5 4 -0.6 13 did not.
Group 4 (visceral fat > 31.98, age > 38.5) 3 -3.1 29 3.7 32
Total N 51 - 37 - 88 In the results of our study, the VFT > 31.98 mm was
N, number; s.d., standard deviation.
significantly associated with the presence of steatosis in HIV-
Discussion positive patients, and requires to be checked in additional
HIV-infected populations such as women, children, non-
Obesity represents an emerging health care issue of modern Caucasian populations and those not on cART.
times. A very important fact is that the obesity phenotype is
19
not an entirely reliable predictor of the development of the In our study, the cut-off age point of > 38.5 years was
cardiometabolic syndrome (CMS). The intake of excessive associated with steatosis. Our ROC analysis provided us
20
9
calories and suboptimal physical activity lead to the with a cross section of categories. Lombardi et al. showed
deposition of triglycerides in peripheral and central depots that age is indeed a significant predictor of steatosis,
of fat. Although the peripheral depot has a protective role in confirming that the risk is higher with increasing age. In this
cardiovascular diseases development, excessive caloric same study, BMI and WC were also predictors of the
intake over time overwhelms this depot and fat is transferred development of steatosis and fibrosis.
to the central compartment, leading to central obesity (CO), In a large retrospective study, Sebastiani et al. observed that
27
a fundamental component of the CMS. Waist circumference elevated blood glucose levels were a reliable predictor of
21
is used as the most common anthropometric measurement advanced liver fibrosis. In our cohort, patients with steatosis
of CO, even though it reflects the volumes of both peripheral did have generally higher blood glucose levels, but as a
and central fat tissue compartment. The importance of single predictor, glucose levels were an insensitive measure
quantification of the VFT lies in its specificity. Visceral fat of hepatic steatosis.
tissue behaves as an endocrine organ: it excretes several
proteins, and via direct or indirect actions, it assists in the This study does have several limitations. These include the
22
regulation of numerous physiological and pathophysiological cross-sectional nature of the study and the restriction of the
processes. 23,24 study to male gender only. Women and children make up
large numbers of the HIV-infected in middle- to low-income
The relationship between the WC and the visceral fat countries. The question of the value of VFT is likely to be of
compartment is especially relevant to people living with HIV, importance to this group too. Cross-sectional studies do not
as it is usually a manifestation of drug toxicity and can be answer the question of intervention and of long-term

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