BACKGROUND

Higher levels of small low-density lipoprotein (LDL) and lower levels of high-density lipoprotein (HDL) subclasses have been associated with increased risk of cardiovascular disease. The extent to which HIV infection and HIV/hepatitis C virus (HCV) coinfection are associated with abnormalities of lipoprotein subclasses is unknown.

METHODS

Lipoprotein subclasses were measured by nuclear magnetic resonance (NMR) spectroscopy in plasma samples from 569 HIV-infected and 5948 control participants in the Fat Redistribution and Metabolic Change in HIV Infection (FRAM), Coronary Artery Risk Development in Young Adults (CARDIA), and Multi-Ethnic Study of Atherosclerosis (MESA) studies. Multivariable regression was used to estimate the association of HIV and HIV/HCV coinfection with lipoprotein measures with adjustment for demographics, lifestyle factors, and waist-to-hip ratio.

RESULTS

Relative to controls, small LDL levels were higher in HIV-monoinfected persons (+381 nmol/l, P <0.0001), with no increase seen in HIV/HCV coinfection (-16.6 nmol/l). Levels of large LDL levels were lower (-196 nmol/l, P <0.0001) and small HDL were higher (+8.2 μmol/l, P < 0.0001) in HIV monoinfection with intermediate values seen in HIV/HCV coinfection. Large HDL levels were higher in HIV/HCV-coinfected persons relative to controls (+1.70 μmol/l, P <0.0001), whereas little difference was seen in HIV-monoinfected persons (+0.33, P = 0.075). Within HIV-infected participants, HCV was associated independently with lower levels of small LDL (-329 nmol/l, P <0.0001) and small HDL (-4.6 μmol/l, P <0.0001), even after adjusting for demographic and traditional cardiovascular risk factors.

CONCLUSION

HIV-monoinfected participants had worse levels of atherogenic LDL lipoprotein subclasses compared with controls. HIV/HCV coinfection attenuates these changes, perhaps by altering hepatic factors affecting lipoprotein production and/or metabolism. The effect of HIV/HCV coinfection on atherosclerosis and the clinical consequences of low small subclasses remain to be determined.

The incidence of esophageal cancer has been increasing while the prognosis remains very poor. Endoscopic submucosal dissection (ESD) was developed in Japan for en bloc resection of early gastric cancer with excellent results. The use of ESD in early squamous cell cancer (SCC) of the esophagus in Japan has been increasing with long-term results comparable to those in early gastric cancer. The use of ESD in Barrett's neoplasia in western countries has been challenged by the low complete resection rates and the risk of metachronous lesions from surrounding non-dysplastic Barrett's epithelium. Efforts to combine ESD with other treatment modalities such as radiofrequency ablation in Barrett's neoplasia and chemoradiation in SCC appear to be promising. The use of steroid therapy (local or systemic) has been demonstrated to prevent post-ESD stenosis, which is the most common complication after esophageal ESD.