Factors associated with fractures in HIV-infected persons: which factors matter?

The association between the CD4/CD8 ratio and surgical site infection risk among HIV-positive adults: insights from a China hospital

Purpose

It is well known that the CD4/CD8 ratio is a special immune-inflammation marker. We aimed to explore the relationship between the CD4/CD8 ratio and the risk of surgical site infections (SSI) among human immunodeficiency virus (HIV)-positive adults undergoing orthopedic surgery.

Methods

We collected and analyzed data from 216 HIV-positive patients diagnosed with fractures at the department of orthopedics, Beijing Ditan Hospital between 2011 and 2019. The demographic, surgical, and hematological data for all patients were collected in this retrospective cohort study. We explored the risk factors for SSI using univariate and multivariate logistic regression analysis. Then, the clinical correlation between the CD4 count, CD4/CD8 ratio, and SSI was studied using multivariate logistic regression models after adjusting for potential confounders. Furthermore, the association between the CD4/CD8 ratio and SSI was evaluated on a continuous scale with restricted cubic spline (RCS) curves based on logistic regression models.

Results

A total of 23 (10.65%) patients developed SSI during the perioperative period. Patients with hepatopathy (OR=6.10, 95%CI=1.46-28.9), HIV viral load (OR=8.68, 95%CI=1.42-70.2; OR=19.4, 95%CI=3.09-179), operation time (OR=7.84, 95%CI=1.35-77.9), and CD4 count (OR=0.05, 95%CI=0.01-0.23) were risk factors for SSI (P-value < 0.05). Our study demonstrated that a linear relationship between CD4 count and surgical site infection risk. In other words, patients with lower CD4 counts had a higher risk of developing SSI. Furthermore, the relationship between CD4/CD8 ratio and SSI risk was non-linear, inverse 'S' shaped. The risk of SSI increased substantially when the ratio was below 0.913; above 0.913, the risk of SSI was almost unchanged. And there is a 'threshold-saturation' effect between them.

Conclusion

Our research shows the CD4/CD8 ratio could be a useful predictor and immune-inflammation marker of the risk of SSI in HIV-positive fracture patients. These results, from a Chinese hospital, support the beneficial role of immune reconstitution in HIV-positive patients prior to orthopedic surgery.

People living with HIV and fracture risk

PLHIV have an increased risk of osteoporosis and fractures when compared with people of the same age and sex. In this review, we address the epidemiology and the pathophysiology of bone disease and fractures in PLHIV. The assessment of fracture risk and fracture prevention in these subjects is also discussed. The spectrum of HIV-associated disease has changed dramatically since the introduction of potent antiretroviral drugs. Today, the survival of people living with HIV (PLHIV) is close to that of the general population. However, the longer life-span in PLHIV is accompanied by an increased prevalence of chronic diseases. Detrimental effects on bone health are well recognised, with an increased risk of osteoporosis and fractures, including vertebral fractures, compared to the general population. The causes of bone disease in PLHIV are not fully understood, but include HIV-specific risk factors such as use of antiretrovirals and the presence of chronic inflammation, as well as traditional risk factors for fracture. Current guidelines recommend the use of FRAX to assess fracture probability in PLHIV age ≥ 40 years and measurement of bone mineral density in those at increased fracture risk. Vitamin D deficiency, if present, should be treated. Bisphosphonates have been shown to increase bone density in PLHIV although fracture outcomes are not available.

Fractures Related to Tenofovir: A Case/Noncase Study in the European Pharmacovigilance Database

BACKGROUND

There is no clear consensus on the relationship between tenofovir (TDF) and fracture risk because the studies published so far present contradictory findings.

STUDY QUESTION

Our objective was to detect, from the European pharmacovigilance database (EudraVigilance), a signal of fracture risk during TDF exposure in patients infected with HIV.

METHODS

Herein, we analyze all the cases of fractures suspected to be related to TDF recorded in EudraVigilance between 2001 and November 10, 2016. A case/noncase method was used to assess the association between fractures and TDF, calculating proportional reporting ratios (PRRs) and their 95% confidence intervals (CIs) as a measure of disproportionality. According to the Medical Dictionary for Regulatory Activities (MedDRA) terminology, osteoporotic fractures are included in High Level Group Term (HLGT) "Fractures" and traumatic fractures in HLGT "Bone and joint injuries," so, we selected cases included in both HLGTs. The noncases used as controls were all the remaining adverse drug reaction reports recorded in EudraVigilance during the same period.

RESULTS

There were 68,113 cases of fractures in the 4,776,472 reports recorded in EudraVigilance during the study period. TDF was involved in 181 cases. The median latency period until the appearance of fracture was 995 days. TDF was present as the only suspect drug in 140 cases. The PRR of TDF and fractures was 1.11 (95% CI, 0.96-1.28). Nevertheless, disproportionality was observed for some types of fractures: osteoporotic fractures (PRR 17.24; 95% CI, 9.90-30.01), bone fissure (PRR 16.60; 95% CI, 6.11-45.10), and pathological fracture (PRR 4.40; 95% CI, 2.77-7.00).

CONCLUSIONS

Our findings do not show a disproportionality for fractures in patients treated with TDF, although disproportionality was found for some types of fractures, mainly osteoporotic fractures.

Impact of Antiretroviral Drugs on Fracture Risk in HIV-Infected Individuals: A Case-Control Study Nested Within the French Hospital Database on HIV (FHDH-ANRS CO4)

BACKGROUND

HIV-infected patients have lower bone mineral density and a higher incidence of fractures than the general population of the same age and sex. To assess the impact of antiretroviral (ARV) drugs exposure on the risk of osteoporotic fractures, we conducted a nested case-control study.

METHODS

Cases were individuals enrolled while ARV-naive, with a first prospectively recorded fracture between 2000 and 2010. Controls were randomly selected after matching for sex, age (±3 years), period of HIV diagnosis (<1997/≥1997), and clinical center. The risk of fracture was analyzed with conditional logistic regression models, using different ways to model ARV exposure. All exposure variables and potential confounders were included in multivariable models.

RESULTS

Among 861 reviewed cases, 261 fractures were osteoporotic and 254 of cases were matched to at least one control (376 controls). The median year of fracture diagnosis was 2007 (interquartile range 2004-2009): 49% of patients had been exposed to tenofovir disoproxil fumarate (TDF) and 82% to protease inhibitors (PIs). After taking into account the transmission group, AIDS status, geographic origin, body mass index, current smoking status, alcohol consumption, exposure to systemic glucocorticoids, and the period of enrollment, there was no association between the risk of fracture and exposure to TDF [odds ratio for cumulative exposure: 1.04 (0.86-1.27), similar results for ever-exposed subjects], to nucleoside reverse transcriptase inhibitors, or to PIs [odds ratio for cumulative PI exposure: 1.02 (0.92-1.12)].

CONCLUSIONS

We found no evidence of an excess risk of fracture after exposure to TDF or PIs. This has important implications for the debate concerning tenofovir alafenamide versus generic TDF.

High Prevalence of Sarcopenia in HIV-Infected Individuals

Background

Sarcopenia is a geriatric syndrome that leads to a loss of functionality and mortality.

Methods

We assessed the prevalence of sarcopenia in HIV-infected patients attended in our HIV Unit who had at least two DXA scans from 2000 to 2016 (1,720 DXA scans from 860 individuals). Sarcopenia was determinate according to appendicular skeletal muscle mass index (ASM) calculated as the ratio between skeletal muscle mass index (SMI) by DXA and height² (kg/m²). We stratified patients by gender and age (<40, 41-50, and >50 years) and according to the interval between DXAs (≤3, 3-7, 7-10, >10 years). The statistical analysis was performed using SPSS version 19.

Results

Median (IQR) age was 52 (47; 57) years, and 76% were male. The median (IQR) time with HIV infection was 8 (3; 15) years. The prevalence of sarcopenia was 25.7% (95% CI, 22.8-28.7), more prevalent in those aged >50 years (27.8%). Stratifying by gender, 43% of women aged >50 years presented sarcopenia compared with 8.8% of men. The frequency of sarcopenia increased from 37.6% to 49.4% when interval between DXA was 7-10 years (n=109), significantly higher in women than in men (p=0.016). In addition to the traditional risk factors, time with HIV infection was associated with sarcopenia [RR 1.780 (95% CI, 1.314-2.411), p=0.001].

Conclusion

The prevalence and progression of sarcopenia in HIV-infected patients were high, mainly among women. Further studies are necessary to assess the best approaches to prevent this condition and its consequences.

The Hidden Burden of Fractures in People Living With HIV

The survival of people living with human immunodeficiency virus (HIV) has increased markedly since the advent of antiretroviral therapy (ART). However, other morbidities have emerged, including osteoporosis. The estimated incidence of fractures at any site in people living with HIV ranges from 0.1 per 1000 person‐years to 8.4 per 1000 person‐years: at least twice that of people without HIV. This increased risk seems to be related to HIV itself and its treatment. Risk factors for bone disease in HIV‐positive (HIV⁺) subjects include both classical risk factors for osteoporosis and fracture and factors linked to HIV itself, such as inflammation, reconstitution syndrome, low CD4, ART, and co‐infection with hepatitis B and C viruses. The risk of fractures in these individuals can be at least partially assessed by measurement of BMD and the Fracture Risk Assessment Tool (FRAX™). Only alendronate and zoledronic acid have been studied in HIV⁺ individuals; both show beneficial effects on BMD, although data on fracture reduction are not available. © 2018 The Authors. JBMR Plus Published by Wiley Periodicals, Inc. on behalf of American Society for Bone and Mineral Research.