A cross-sectional study of HIV-infected men over 21 and under the age of 50 years who were naïve to ART in a tertiary teaching hospital in central Madrid, Spain.
Subjects and study design; Inclusion criteria and ethical concerns
245 adult men (over 21 and under the age of 50 years) who came to the Infectious Disease Division appointment in Hospital Fundación Jimenez Díaz in Madrid, from January 1st, 2014 to September 30th, 2017, with a recent diagnosis of HIV infection, without previous HIV treatment. All subjects underwent a baseline DXA scan (HOLOGIC QDR 4500C, Marlborough, MA, USA) performed prior to start ART. Further, all patients who started treatment between May 1st and September 30th, 2017 were invited to participate in a substudy on bone mineral metabolism. The protocol for this study was approved by the clinical research ethics committee of the Hospital Fundación Jimenez Diaz (approval code: PIC, 155-2016, approved on 20 December 2016) and is in adherence with the tenets of the Declaration of Helsinki. All patients provided signed informed consent before being included in the study.
Exclusion criteria were as follow: patients over 50 years old, previous HIV or bone-targeting treatment (denosumab, vitamin D), treatment with systemic corticosteroids, diagnosed of diabetes, rheumatologic and renal diseases, thyrotoxicosis, advanced liver disease, malabsorption syndrome, neoplasms or previous fragility fractures.
Measurements and reference values
We gathered such epidemiologic data as age, race, and country of birth. Lifestyle-related aspects used as study variables included alcohol, tobacco, and drug consumption, physical activity, and approximate calcium intake. Additionally, anthropometric data were collected for all patients. Blood test was done fasting, measured by Advia 2400 system (Siemens , Munich, Germany) for values related to calcium, phosphorus and vitamin D. Immunological and virologic parameters (i.e., CD4+, CD8+, and HIV-1 viral load) were measured by PCR (Roche, Basel, Switzerland).
Underweight was defined as a body mass index (BMI) of <20 kg/m2. The values related to bone and mineral metabolism used were the following: 25OH Vitamin D (30-50 ng/ml), and parathormone (PTH) (10–70 pg/ml). Patients considered smokers if they were current or past tobacco users; consumers of alcohol if their total intake was over 30 g/day; and drug users (cocaine, mephedrone, amphetamines, ketamine, GHB) if any of these drugs were taken at least once weekly. For the purposes of this study, sufficient physical exercise was a minimum of 120 minutes per week. Three servings of calcium-rich foods (e.g., milk, cheese, other dairy products) daily was considered an appropriate intake.
DXA scan was performed before the start of ART. BMD was determined by bone densitometry in lumbar spine (LS), and femoral neck (FN). Being our sample subjects under 50 year and according to the World Health Organization (WHO) guidelines, the subjects were classified with Z-score, considering Low BDM values under -2.(4)
Statistical Analysis
Qualitative variables were expressed in terms of frequency and percentages. Based on the results of the Kolmogorov-Smirnov test for normality, quantitative variables were measured as either mean and standard deviation or median and interquartile range (IQR). Qualitative variables were analyzed using the Chi-squared test or Fisher’s exact test. Quantitative variables were compared using Student’s t test. For all determinations, we used R software version 3.6.0 (R Core team (2020); R Foundation for Statistical Computing, Vienna, Austria), and statistical significance was set at p < 0.05.