Interleukin-6 and platelet protagonists in T lymphocyte and virological response

Systemic inflammation-based scores and mortality for all causes in HIV-infected patients: a MASTER cohort study

Background

Two biomarkers, the neutrophil to lymphocyte ratio (NLR) and platelet to lymphocyte ratio (PLR), have been shown to be indicative of systemic inflammation and predictive of mortality in general population. We aimed to assess the association of NLR and PLR, with risk of death in HIV-infected subjects when also taking account of HIV-related factors.

Methods

We conducted a multicenter Italian cohort study from 2000 to 2012 including HIV-infected subjects naïve at antiretroviral treatment.

The associations of NLR and PLR with all-cause mortality were tested by univariate and multivariate analyses using both time independent and dependent Cox proportional hazard models. We also fitted models with a cubic-spline for PLR and NLR to evaluate the possible non-linear relationship between biomarkers values and risk of death.

Results

Eight-thousand and two hundred thirty patients (73.1% males) with a mean age of 38.4 years (SD 10.1) were enrolled. During a median follow-up of 3.9 years, 539 patients died. PLR < 100 and ≥ 200, as compared to PLR of 100–200, and NLR ≥ 2, as compared to < 2, were associated with risk of death at both univariate and multivariate analyses. Using multivariate models with restricted cubic-splines, we found a linear relationship of increasing risk of death with increasing values for NRL over 1.1, and an U-shape curve for PLR, with higher mortality risk for values higher or lower than 120.

Conclusions

Our data suggest that NLR and PLR can reflect the severity of the underlying systemic disturbance of the inflammatory process and coagulation leading to augmented mortality in HIV positive subjects.

Electronic supplementary material

The online version of this article (doi:10.1186/s12879-017-2280-5) contains supplementary material, which is available to authorized users.

Thrombocytopenia is associated with an increased risk of cancer during treated HIV disease

OBJECTIVE

To assess the relationship between platelet counts and risk of AIDS and non-AIDS-defining events.

DESIGN

Prospective cohort.

METHODS

EuroSIDA patients with at least one platelet count were followed from baseline (first platelet ≥ 1 January 2005) until last visit or death. Multivariate Poisson regression was used to assess the relationship between current platelet counts and the incidence of non-AIDS-defining (pancreatitis, end-stage liver/renal disease, cancer, cardiovascular disease) and AIDS-defining events.

RESULTS

There were 62 898 person-years of follow-up (PYFU) among 12 279 patients, including 1168 non-AIDS-defining events [crude incidence 18.6/1000 PYFU, 95% confidence interval (CI) 17.5-19.6] and 735 AIDS-defining events (crude incidence 11.7/1000 PYFU, 95% CI 10.8-12.5). Patients with thrombocytopenia (platelet count ≤100 × 10/l) had a slightly increased incidence of AIDS-defining events [adjusted incidence rate ratio (aIRR) 1.42, 95% CI 1.07-1.86], when compared to those with platelet counts 101-200 × 10/l, whereas the incidence of non-AIDS-defining events was more than two-fold higher (aIRR 2.66, 95% CI 2.17-3.26). Among non-AIDS-defining events, the adjusted incidence of cancer (aIRR 2.20, 95% CI 1.61-3.01), but not cardiovascular disease (aIRR 0.66, 95% CI 0.32-1.34), was significantly higher in patients with thrombocytopenia. The association between thrombocytopenia and cancer remained unaltered in sensitivity analyses requiring repeated platelet counts to confirm thrombocytopenia and lagging platelets by 1 year prior to clinical events.

CONCLUSION

Patients with thrombocytopenia had increased incidence of AIDS-defining and non-AIDS-defining events, but the association with the latter, in particular cancer, was stronger. Future studies should investigate whether the pathophysiological processes underlying thrombocytopenia are associated with the development of cancer during treated HIV disease.

The role of alcohol on platelets, thymus and cognitive performance among HIV-infected subjects: are they related?

Our objective was to evaluate whether thrombocytopenia and small thymus volume, which may be associated with hazardous alcohol consumption, are predictors of cognitive performance after highly-active antiretroviral treatment (HAART). To achieve this goal 165 people living with HIV starting HAART underwent thymus magnetic resonance imaging, cognitive (HIV Dementia Score [HDS] and the California Verbal Learning Test [CVLT]), immune and laboratory assessments at baseline and after 6 months of HAART. At baseline, hazardous alcohol consumption was significantly correlated with both thymus size (r = -0.44, p = 0.003) and thrombocytopenia (r = 0.28, p = 0.001). Of interest, thrombocytopenic patients were characterized by a smaller thymus size. Individuals with and without cognitive impairment differed in alcohol consumption, platelet counts and thymus size, suggesting that they may be risk factors for neurological abnormalities. In fact, after HAART hazardous alcohol use associations with thrombocytopenia were related to cognitive decline (learning = -0.2 +/- 0.8, recall = -0.3 +/- 0.1 and HDS = -0.5). This contrasted with improvements on every cognitive measure (learning = 1.6 +/- 0.3, p = 0.0001, recall = 2.2 +/- 0.4, p = 0.0001 and HDS = 1.0, p = 0.05) in those with neither alcohol use nor thrombocytopenia. In adjusted analyses for sociodemographics, adherence and immune measurements, reduced thymus size was associated with a 90% and thrombocytopenia with a 70% increase in the risk of scoring in the demented range after HAART (RR = 1.9, p < 0.05 and RR = 1.7, p = 0.03) and with low CVLT scores (thymus volume RR = 2.0, p = 0.04, chronic alcohol use p = 0.05 and thrombocytopenia p = 0.06). Thymus volume and platelet counts were negatively affected by alcohol and were predictors of cognitive performance and improvements after HAART. These results could have important clinical and therapeutic implications.