Immunological effects of antiretroviral therapy

The striking decline in HIV load with highly active antiretroviral combination therapy (HAART) is accompanied by substantial improvements in immune function, even in patients with more advanced disease. These include a general reduction in immune activation with increases in total CD4 and CD8 cell counts, memory and naive T cell subsets and antigen responses to certain opportunistic pathogens. At this time, it appears that HAART-induced improvements in function are limited to those T cells that have not yet been completely depleted by HIV. Long-term studies are needed to determine whether complete functional restoration of the repertoire is possible. Clinically, HAART improves survival and reduces progression of HIV disease. Some patients with active opportunistic disorders demonstrate complete or partial resolution of the infection or malignancy. However, persons with subclinical Mycobacterium avium complex or cytomegalovirus retinitis and those with chronic hepatitis B virus infection may sometimes experience acute flares if prophylactic therapy against the underlying disorder is not included in the regimen.

Comparison of clinical features, CD4 and CD8 responses among patients with acute HIV-1 infection from Geneva, Seattle and Sydney

OBJECTIVE

To compare the clinical features and T-cell subsets among 160 patients with acute HIV-1 infection not treated with antiretroviral agents from three different locations (Geneva, Seattle and Sydney).

DESIGN

Patients with documented acute HIV-1 infection were enrolled in four prospective studies: one randomized placebo controlled trial (RCT) and three observational cohort studies.

SETTING

All patients were diagnosed and followed in three university affiliated tertiary clinical care centers.

METHODS

The chi-square test was used for comparing proportions and one way analysis of variance (ANOVA) for comparing continuous variables among these groups. Multiple regression analysis was used to identify the variables independently associated with the duration of acute HIV-1 infection. The differences in mean CD4 and CD8 load between centers were assessed using the random-effect models for the longitudinal data.

RESULTS

Minor differences were noted in the frequency of symptoms among subjects enrolled at different locations. RCT patients reported a longer duration of symptoms (31 days) compared with that for observational patients (15 days; P < 0.0001). For the most common symptoms such as fever, skin rash, arthralgia, myalgia, and headaches, a longer duration was observed in the RCT group compared with that for observational patients (P range, 0.001 to < 0.0001). T-cells subsets within 100 days of seroconversion did not statistically differ by centre or by mode of recruitment.

CONCLUSIONS

These results suggest a selection bias toward patients with longer symptomatic acute HIV-1 infection enrolled in the RCT. Data collected from RCT are not comparable to that collected in observational studies. However, data from collaborative international studies can be combined.

Olestra consumption is not associated with macular pigment optical density in a cross-sectional volunteer sample in Indianapolis

The associations between the intake of the fat-substitute olestra and the concentrations of macular carotenoid pigments and serum lutein and zeaxanthin were investigated in a volunteer cross-sectional sample in Indianapolis. The study was conducted in January through March, 1998 after olestra-containing savory snacks had been sold in central Indiana for a year. Volunteers (n = 280) aged 18-50 y were recruited to make a single clinic visit during which macular pigment optical density (MPOD) was determined by psychophysical flicker photometry, serum was obtained for determination of lutein and zeaxanthin concentration, usual intake of olestra, carotenoids and nutrients were assessed by 1-y food frequency questionnaire, and health habits including smoking, physical characteristics such as eye color, demographics and medical history were determined by questionnaire. Intake of olestra at least one time per month for the past year was reported by 81:280 subjects and their mean, median and 90(th) percentile intakes were 1.09, 0.34 and 2.43 g olestra/d, respectively. Mean macular pigment optical density was not significantly different between olestra consumers and nonconsumers (0.213 +/- 0.014 vs. 0.211 +/- 0.010) nor was serum lutein and zeaxanthin concentration (0.361 +/- 0.017 vs. 0.375 +/- 0. 013 micromol/L) or intake (1242 +/- 103 mg/d vs. 1042 +/- 58 mg/d) in one-way or two-way ANOVA. Olestra intake was not associated with MPOD or serum lutein and zeaxanthin before or after correction for significant covariates of MPOD. Thus, olestra intake over the past year in a cross-sectional volunteer sample in Indianapolis was not associated with MPOD.

A syndrome of lipoatrophy, lactic acidaemia and liver dysfunction associated with HIV nucleoside analogue therapy: contribution to protease inhibitor-related lipodystrophy syndrome

BACKGROUND

Lipodystrophy (LD; peripheral lipoatrophy, central adiposity) hyperlipidaemia and insulin resistance often complicate protease inhibitor-containing antiretroviral therapy. Lipoatrophy and abdominal distension were observed in protease inhibitor-naive nucleoside analogue reverse transcriptase inhibitor (NRTI) recipients with lactic acidaemia and hepatic impairment, which are known NRTI-induced mitochondrial toxicities.

DESIGN AND SETTING

Case-control study in a university-based outpatient clinic.

PATIENTS AND METHODS

The patients studied included 14 NRTI recipients with lipoatrophy, 32 antiretroviral-naive patients without LD, 28 NRTI recipients without LD, 44 combined NRTI-protease inhibitor recipients without LD, and 102 NRTI-protease inhibitor recipients with LD. Data was obtained on body composition (questionnaire, physical examination, dual-energy x-ray absorptiometry and abdominal computerized tomography), with biochemical, lipid and glycaemic parameters.

RESULTS

The NRTI-LD syndrome was characterized by recent onset fatigue and nausea, peripheral lipoatrophy (6 kg loss over 4 months), abdominal distension (ascites +/- hepatomegaly) and elevated lactate (4.6, 1.1, 1.2, 1.4 and 1.7 mmol/l, respectively; P< 0.0001) and liver enzymes. Cases without hepatic involvement also had lower body fat and greater lactate than unaffected controls. Metabolic disturbances and weight improved after cessation. The NRTI-LD syndrome differed from protease inhibitor-related LD syndrome by the presence of recent onset symptoms and weight loss, higher lactate and alanine aminotransferase, and lower albumin, cholesterol, triglycerides, glucose and insulin. In treated controls, current stavudine therapy, protease inhibitor duration, and lactic acidaemia were independently associated with both lipoatrophy and abdominal obesity; total NRTI duration was also associated with lipoatrophy, and lamivudine and protease inhibitor duration with buffalo hump.

CONCLUSIONS

A syndrome of lipoatrophy, constitutional illness, lactic acidaemia and hepatic dysfunction can complicate NRTI therapy. Both protease inhibitor and NRTI therapies, particularly if associated with lactic acidaemia, contribute to LD syndrome, but have some distinguishable clinical and metabolic effects.

B-cell stimulation and prolonged immune deficiency are risk factors for non-Hodgkin's lymphoma in people with AIDS

OBJECTIVES

To identify risk factors for non-Hodgkin's lymphoma (NHL) in people with HIV infection.

DESIGN AND SETTING

Case-control study in Sydney, Australia.

PARTICIPANTS AND METHODS

Two hundred and nineteen patients with AIDS-related NHL were compared with 219 HIV-infected controls without NHL, matched for CD4 positive cell count and date of specimen collection. Data on demographic, infectious, treatment-related and immunological factors were abstracted by medical record review. The association between demographic factors, sexually transmissible diseases, HIV-related opportunistic infections, anti-viral therapy, duration of immune deficiency and indices of immune stimulation and risk of NHL were derived for these groups.

RESULTS

In a multivariate model, there were two independent groups of predictors of NHL risk. The first was duration of immunodeficiency, as measured by longer time since seroconversion (P for trend 0.008), and lower CD4 positive cell count 1 year prior to the time of NHL diagnosis (P for trend 0.009). The second predictor was B-cell stimulation, as indicated by higher serum globulin (a surrogate marker for serum immunoglobulin, P for trend 0.044) and HIV p24 antigenaemia [odds ratio (OR) for p24 positivity, 1.82; 95% confidence interval (CI), 1.15-2.88]. Indices of B-cell stimulation preceded the diagnosis of NHL by several years. Factors not related to NHL risk included clinical indices of Epstein-Barr virus infection and receipt of individual nucleoside analogue antiretroviral agents. Combination therapy with these agents was associated with a non-significant reduction in NHL risk (OR, 0.68; 95% CI, 0.39-1.18).

CONCLUSIONS

Markers of long-standing immune deficiency and B-cell stimulation were associated with an increased risk of developing NHL. Unless the strongest risk factor for NHL, immune deficiency, can be reversed, NHL is likely to become proportionately more important as a cause of morbidity and mortality in people with HIV infection.

Estimating the population impact in Australia of improved antiretroviral treatment for HIV infection

OBJECTIVE

To estimate the reduction in AIDS incidence, if any, which has occurred in Australia following the availability of new combination antiretroviral treatments from 1995.

DESIGN

Analyses were based on national surveillance data.

METHODS

Back-projection analyses based on quarterly AIDS counts to the end of 1994 were used to estimate the numbers of AIDS diagnoses which would have occurred if new treatments had not reduced the rate of progression to AIDS. Estimates of the reduction in AIDS diagnoses between 1995 and 1998 were made by subtracting the observed delay-adjusted AIDS counts from the predicted AIDS incidence.

RESULTS

AIDS incidence between 1995 and 1998 was estimated to have been reduced by 1093 cases (33%) following the availability of new antiretroviral treatments (95% confidence interval 831 (25%) to 1425 (43%) cases). The majority of this reduction in AIDS incidence was estimated to have occurred during 1997 (434 cases) and 1998 (427 cases).

CONCLUSIONS

AIDS incidence in Australia has declined since 1995 coincidental with introduction of new antiretroviral treatments. In particular, the more rapid decline in AIDS incidence since mid-1996 coincided with the availability and widespread uptake of combinations including protease inhibitors.

Antiretroviral therapy in adults: updated recommendations of the International AIDS Society-USA Panel

OBJECTIVE

To update recommendations for antiretroviral therapy for adult human immunodeficiency virus type 1 (HIV-1) infection, based on new information and drugs that are available.

PARTICIPANTS

A 17-member international physician panel with antiretroviral research and HIV patient care experience initially convened by the International AIDS Society-USA in December 1995.

EVIDENCE

Available clinical and basic science data including phase 3 controlled trials; data on clinical, virologic, and immunologic end points; research conference reports; HIV pathogenesis data; and panel expert opinion. Recommendations were limited to therapies available (US Food and Drug Administration approved) in 1999.

CONSENSUS PROCESS

The panel assesses new research reports and interim results and regularly meets to consider how the new data affect therapy recommendations. Recommendations are updated via full-panel consensus. Guidelines are presented as recommendations if the supporting evidence warrants routine use in the particular situation and as considerations if data are preliminary or incomplete but suggestive.

CONCLUSIONS

The availability of new antiretroviral drugs has expanded treatment choices. The importance of adherence, emerging long-term complications of therapy, recognition and management of antiretroviral failure, and new monitoring tools are addressed. Optimal care requires individualized management and ongoing attention to relevant scientific and clinical information in the field.

Impact of early HIV-1 RNA and T-lymphocyte dynamics during primary HIV-1 infection on the subsequent course of HIV-1 RNA levels and CD4+ T-lymphocyte counts in the first year of HIV-1 infection. Sydney Primary HIV Infection Study Group

Plasma HIV-1 RNA and CD4+ T-cell counts after HIV-1 seroconversion are important independent markers that predict the clinical course of HIV-1 infection. The prognostic significance of these parameters during primary HIV-1 infection, however, remains largely unknown. In a cohort of 53 male study subjects (age, 33 +/- 7 years), who consecutively presented with primary HIV-1 infection, we analyzed the relationship between early plasma HIV-1 RNA, CD4+ and CD8+ T-cell counts, beta2-microglobulin, and p24-antigen levels determined in the first 3 months and subsequent plasma HIV-1 RNA levels and CD4+ T-cell counts 6 to 12 months after onset of primary symptoms. Peak, nadir, and median HIV-1 RNA levels in the first 30 days were already significantly associated with HIV-1 RNA levels at 6 to 12 months (p = .02, p < .0001, and p = .01, respectively). Similarly, early nadir and median CD4+ T-lymphocyte counts in the first 30 days showed a significant relationship with CD4+ T-cell counts at 6 to 12 months (p = .009 and p = .0008, respectively). Study subjects with an early decline of CD4+ counts to <500 cells/microl had an eightfold higher risk that CD4+ counts were <500 cells/microl at 1 year. Of all evaluated virologic parameters, only nadir HIV-1 RNA at 76 days predicted CD4+ counts at 6 to 12 months (p = .006). Early HIV-1 RNA levels and CD4+ counts are already associated with the time course of those parameters 6 to 12 months after onset of symptoms. Nadir viral load was the strongest predictor of HIV-1 RNA levels as well as of CD4+ counts at 6 to 12 months. An early decline of CD4+ T lymphocytes may be a useful clinical prognostic marker for rapid disease progression.

Effect of long-term infection with nef-defective attenuated HIV type 1 on CD4+ and CD8+ T lymphocytes: increased CD45RO+CD4+ T lymphocytes and limited activation of CD8+ T lymphocytes

Members of the Sydney Blood Bank Cohort (SBBC) have been infected with an attenuated strain of HIV-1 with a natural nef/LTR mutation and have maintained relatively stable CD4+ T lymphocyte counts for 14-18 years. Flow cytometric analysis was used to examine the phenotype of CD4+ and CD8+ T lymphocytes in these subjects, including the immunologically important naive (CD45RA+CD62L+), primed (CD45RO+), and activated (CD38+HLA-DR+ and CD28-) subsets. The median values were compared between the SBBC and control groups, comprising age-, sex-, and transfusion-matched HIV-1-uninfected subjects; transfusion-acquired HIV-1-positive LTNPs; and sexually acquired HIV-1-positive LTNPs. Members of the SBBC not only had normal levels of naive CD4+ and CD8+ T lymphocytes, but had primed CD45RO+ CD4+ T lymphocytes at or above normal levels. Furthermore, these primed cells expressed markers suggesting recent exposure to specific antigen. SBBC members exhibited variable activation of CD8+ T lymphocytes. In particular, SBBC members with undetectable plasma HIV-1 RNA had normal levels of activated CD8+ T lymphocytes. Therefore, the result of long-term infection with natural nef/LTR mutant HIV-1 in these subjects suggests a decreased cytopathic effect of attenuated HIV-1 on susceptible activated CD4+ T lymphocyte subsets in vivo, and minimal activation of CD8+ T lymphocytes.

Dual efficacy of lamivudine treatment in human immunodeficiency virus/hepatitis B virus-coinfected persons in a randomized, controlled study (CAESAR). The CAESAR Coordinating Committee

The efficacy and safety of lamivudine in persons coinfected with human immunodeficiency virus (HIV) type 1 and hepatitis B virus (HBV) were examined in the CAESAR study, a randomized placebo-controlled trial assessing the addition of lamivudine (150 mg 2x/day) or lamivudine (150 mg 2x/day) plus loviride (100 mg 3x/day) to zidovudine-containing background antiretroviral treatment. Baseline hepatitis B surface antigen (HBsAg) results were available for 1790 study subjects, of whom 122 (6.8%) tested positive. Retrospective analyses for serial HBV DNA, HBsAg, and hepatitis B e antigen (HBeAg) were performed on stored sera from 118 HBsAg-positive subjects. HBV DNA and HBeAg were present in 83% and 63%, respectively. At weeks 12 and 52, median log10 HBV DNA change was -2.0 and -2.7, respectively, in the lamivudine arms, compared with no reduction among placebo recipients (P<.001). A trend to lower alanine transferase level, and delayed progression of HIV-1 disease (relative hazard, 0.26; 95% confidence interval, 0.08-0.80) were also seen in the lamivudine arms, compared with the placebo group.

Potent antiretroviral therapy of primary human immunodeficiency virus type 1 (HIV-1) infection: partial normalization of T lymphocyte subsets and limited reduction of HIV-1 DNA despite clearance of plasma viremia

Antiretroviral therapy commenced during primary human immunodeficiency virus type 1 (HIV-1) infection (PHI) may limit the extent of viral replication and prevent early loss of HIV-specific CD4 lymphocyte function. We studied the effect of current standard therapy (2 nucleoside analogues and a protease inhibitor) in 16 patients with symptomatic PHI. In the 13 patients who completed 1 year of treatment, plasma HIV RNA was <50 copies/mL and median CD4 cell counts were comparable to HIV-uninfected controls, with naive (CD45RA+CD62L+), primed (CD45RO+), and T cell receptor Vbeta subsets all within normal ranges. However, HIV-1 DNA levels in treated and untreated PHI patients were similar. Furthermore, CD8 cell counts remained elevated, including activated (CD38+HLA-DR+), replicating (Ki-67+), and cytotoxic (perforin+CD28-) lymphocytes. In conclusion, early antiretroviral therapy resulted in clearance of viremia and prevented loss of crucial CD4 subsets. The persistence of HIV-1 DNA together with increased CD8 T lymphocyte turnover and activation indicate continued expression of viral antigens.

Immune reconstitution in HIV-1 infected subjects treated with potent antiretroviral therapy

The introduction of potent antiretroviral drug regimens contributed to a decline in HIV-1 associated morbidity and mortality. Clinical observations of spontaneous remission of previously untreatable opportunistic infections in subjects on highly active antiretroviral therapy (HAART) reflect the substantial degree of immune reconstitution which can be achieved by those therapies. A biphasic increase of CD4+ T lymphocytes has been reported including naive (CD45RA+) and memory (CD45RO+) cell subsets. Proliferative lymphocyte responses to recall antigens and mitogens are enhanced over time, while T lymphocyte activation is largely reduced and T cell receptor (TCR) repertoires are partly restored. Proliferative lymphocyte responses specific to HIV-1 antigens, in contrast, remain weak. A complete normalisation of HIV-1 associated immunological alterations has not been reported so far, but the observation period of subjects on potent antiretroviral therapies is still relatively short.

Phenotypic analysis of CD8+ T lymphocytes in a cohort of HIV type 1-infected patients treated with saquinavir, ritonavir, and two nucleoside analogs for 1 year, and association with plasma HIV type 1 RNA

The phenotype of circulating CD8+ T lymphocytes and its association with plasma HIV-1 RNA were analyzed in 34 HIV-1-infected subjects, who were treated with saquinavir, ritonavir, and two nucleoside analogs (HAART) for 1 year. Four-color flow cytometry was applied to measure the expression of cell surface antigens CD38, HLA-DR, CD45RA, CD28, and CD62L on CD8+ T lymphocytes. The results were compared with data on 35 HIV-1-seronegative subjects, 18 untreated asymptomatic HIV-1-seropositive individuals, and 24 HIV-1-infected subjects receiving reverse transcriptase inhibitors (RTIs). Subjects receiving HAART showed a significantly elevated number and percentage of CD38- and HLA-DR-positive and CD28-negative CD8+ T lymphocytes as well as a lower percentage of naive (CD45RA+62L+) CD8+ T lymphocytes compared with HIV-1-uninfected controls. Even subjects with undetectable plasma HIV-1 RNA showed a persistent elevation of activated CD8+ T lymphocytes. However, fewer activated CD8+ T lymphocytes were observed in subjects receiving HAART than in untreated individuals and subjects administered RTIs. In individuals receiving RTIs, CD8+ cell activation was not significantly reduced compared with untreated subjects. Of all evaluated activation markers, the percentage of CD8+ T lymphocytes expressing CD38 and the combination of CD38 and HLA-DR showed the best correlation with plasma HIV-1 RNA. The persistence of CD8+ T lymphocyte activation in subjects receiving HAART strongly suggests ongoing viral activity, even in subjects with undetectable plasma HIV-1 RNA. A complete normalization of immunologic changes of CD8+ T lymphocytes would therefore require a more potent drug regimen or a longer duration of therapy.

Changes to AIDS dementia complex in the era of highly active antiretroviral therapy

OBJECTIVES

To determine the protective efficacy of highly active antiretroviral therapy (HAART) against AIDS dementia complex (ADC) relative to other initial AIDS-defining illnesses (ADIs), Australian AIDS notification data over recent years were examined.

METHODS

All initial ADIs in Australia over the period 1992-1997 were included. Three initial ADI groups were established: ADC; other predominantly central nervous system (CNS) ADIs (toxoplasmosis and cryptococcosis); and non-CNS ADIs. For each ADI grouping, the proportion of total ADls, and median CD4 cell count in the pre-HAART era (1992-1995) were compared with the HAART era (1996 and 1997).

RESULTS

Initial ADls peaked in Australia in 1994 (n = 1049), with a gradual decline to 1996 (n = 722), and a marked decline in 1997 (n = 367). ADC constituted 4.4% of initial ADIs over the period 1992-1995, but increased after the introduction of HAART to 6.0% in 1996 and 6.5% in 1997 (P = 0.02). In contrast, the proportion of other CNS ADIs (1992-1995, 8.1%; 1996, 6.0%; 1997, 8.2%; P = 0.41) was stable over the period 1992-1997. The median CD4 cell count at ADC diagnosis increased from 70/mm3 in 1992-1995 to 120/mm3 in 1996 and 170/mm3 in 1997 (P = 0.04). Although the median CD4 cell count also increased significantly over this period for both other CNS ADIs (40-60/mm3; P = 0.02), and non-CNS ADIs (60-70/mm3; P = 0.02), the increase was small.

CONCLUSION

A proportional increase in ADC compared with other ADIs and a marked increase in the median CD4 cell count at ADC diagnosis have occurred since the introduction of HAART in Australia. These changes suggest that HAART has a lesser impact on ADC than on other ADIs, with the poor CNS penetration of many antiretroviral agents a possible explanation.

Dietary carotenoids and certain cancers, heart disease, and age-related macular degeneration: a review of recent research

Key epidemiologic studies show associations between high dietary intakes of certain carotenoid-containing fruits and vegetables and reduced risk of prostate cancer, breast cancer, head and neck cancers, cardiovascular disease, and age-related macular degeneration, although overall the evidence is inconsistent. Little is known about the potential biochemical mechanisms whereby carotenoids might protect against disease, and human intervention trials are limited to high dose beta-carotene, which is not protective against lung cancer or cardiovascular disease. Authoritative scientific organizations continue to emphasize increased consumption of fruits and vegetables but do not make specific recommendations for carotenoids because of a lack of data that directly link them to disease reduction.

CD8+ anti-human immunodeficiency virus suppressor activity (CASA) in response to antiretroviral therapy: loss of CASA is associated with loss of viremia

CD8+ anti-human immunodeficiency virus (HIV) suppressor activity (CASA) defines the noncytolytic suppression of HIV mediated by secreted soluble factors. Changes in CASA in patients receiving combination antiretroviral therapy have not been described. Thirty-two HIV-infected patients receiving mono- or dual therapy for 52 weeks followed by highly active antiretroviral therapy (HAART) for a further 52 weeks were analyzed. T cell number and functional subsets, cutaneous delayed-type hypersensitivity, and plasma HIV RNA were assessed in 17 patients for CASA. Prior to therapy, CASA correlated inversely with HIV RNA (P<.001). Dual therapy yielded greater and more sustained changes in CASA than monotherapy, but HAART decreased CASA to levels observed in HIV-uninfected individuals. The magnitude of HIV RNA suppression correlated significantly with a decrease in activated CD8+ T lymphocytes (CD38+HLA-DR+), increases in naive CD4+ T lymphocytes (CD45RA+62L+), and increases in the delayed-type hypersensitivity score. However, changes in CASA did not correlate with changes in any T lymphocyte subset. CASA increases with improving immune function but appears more dependent on ongoing HIV replication.

Diagnosis, prediction, and natural course of HIV-1 protease-inhibitor-associated lipodystrophy, hyperlipidaemia, and diabetes mellitus: a cohort study

BACKGROUND

The prevalence and severity of lipodystrophy syndrome with long-term therapy for HIV-1 infection that includes a protease inhibitor is unknown. We studied the natural course of the syndrome to develop diagnostic criteria and identifying markers that predict its severity.

METHODS

We assessed 113 patients who were receiving HIV-1 protease inhibitors (mean 21 months) and 45 HIV-1-infected patients (28 with follow-up) never treated with a protease inhibitor. Lipodystrophy was assessed by questionnaire (including patients' rating of severity), physical examination, and dual-energy x-ray absorptiometry. Body composition and fasting lipid and glycaemic variables were compared with data obtained 8 months previously. Oral glucose tolerance was investigated.

FINDINGS

There was 98% concordance between patients' reports of the presence or absence of lipodystrophy (reported by 83% of protease-inhibitor recipients and 4% of treatment-naïve patients; p=0.0001) and physical examination. Patients' ratings of lipodystrophy were significantly associated with declining total body fat (p=0.02). Lower body fat was independently associated with longer duration of protease-inhibitor therapy and lower bodyweight before therapy, and more severe lipodystrophy was associated with higher previous (p < 0.03) and current (p < or = 0.01) triglyceride and C-peptide concentrations, and less peripheral and greater central fat (p=0.005 and 0.09, respectively). Body fat declined a mean 1.2 kg over 8 months in protease-inhibitor recipients (p=0.05). The prevalence of hyperlipidaemia remained stable over time (74% of treated patients vs 28% of naïve patients; p=0.0001). Impaired glucose tolerance occurred in 16% of protease-inhibitor recipients and diabetes mellitus in 7%; in all but three patients these abnormalities were detected on 2 h post-glucose load values.

INTERPRETATION

Diagnosis and rating severity of lipodystrophy is aided by the combination of physical examination, patient's rating, and measurement of body fat, fasting triglycerides, and C-peptide. Weight before therapy, fasting triglyceride, and C-peptide concentrations early in therapy, and therapy duration seem to predict lipodystrophy severity. Lipodystrophy was common and progressive after almost 2 years of protease inhibitor therapy, but was not usually severe. Hyperlipidaemia and impaired glucose tolerance were also common.

Comprehensive classification of symptoms and signs reported among 218 patients with acute HIV-1 infection

Acute HIV-1 illness presents a wide range of clinical manifestations. We assessed a classification and data reduction of clinical features among 218 patients with acute HIV-1 infection enrolled in four prospective seroincidence studies. Factor analysis allows the definition of eight factors based on groups of symptoms and signs: gastrointestinal transit disturbances, weight loss/abdominal pain, lymphadenopathy, myalgia/arthralgia, neurologic features, constitutional and mucocutaneous features, oral candidiasis, and anorexia/pharyngitis. These groups reflected the main target systems involved at the time of acute HIV-1 disease. Grouping of symptoms and signs based on groups of patients is potentially more informative than observations made on individual patients. It might facilitate diagnosis, suggest pathogenic mechanisms and reduce the number of variables for characterizing acute HIV-1 illness.

Long-term prognosis following zidovudine monotherapy in primary human immunodeficiency virus type 1 infection

Eighty-five subjects with symptomatic primary (P) human immunodeficiency virus (HIV) type 1 infection were analyzed in a retrospective cohort study to investigate the long-term clinical benefit of antiretroviral treatment during PHIV infection. Zidovudine treatment was initiated (PHIV treatment group) in 21 persons a median of 9 days after onset of PHIV symptoms and continued for a median of 55 days (range, 21-99). Sixty-four subjects did not receive early antiretroviral treatment (PHIV nontreatment group). After follow-up for 3-10 years, 33 subjects had developed AIDS and 22 subjects had died of AIDS. The median times for progression to AIDS and death were 6.4 and 9.1 years, respectively. Progression rates did not differ between the PHIV treatment and nontreatment groups. Zidovudine treatment initiated during PHIV infection did not improve long-term outcome after symptomatic PHIV infection.

Dietary carotenoids and lung cancer: a review of recent research

Several hundred carotenoid research studies have been published since 1996, when two major intervention trials showed a lack of protective effect of beta-carotene supplements against lung cancer. Recent epidemiologic studies continue to show an association between high dietary intake of beta-carotene and lower risk of lung cancer. New research is attempting to clarify the apparently contradictory results of intervention and epidemiologic studies. Promising areas of investigation include characterizing biologic activities of carotenoids and gaining further insight into whether they may serve primarily as markers for a healthy lifestyle or diet.

Kaposi's sarcoma-associated herpesvirus: a sexually transmissible infection?

We examined sexual behavior as a risk factor for Kaposi's sarcoma-associated herpesvirus (KSHV) infection and examined the relation between KSHV seropositivity and development of KS in cross-sectional and cohort studies of 130 homosexual men diagnosed with AIDS in Sydney, Australia during the period from 1991 to 1993. KSHV serology was measured using antibody tests to latency-associated nuclear antigen (LANA) and lytically expressed open reading frame (ORF) 65.2. In the cross-sectional analysis, 52% (68) of study subjects were KSHV-seropositive by either assay. KSHV-seropositive men were significantly more likely to be seropositive to both herpes simplex type 2 (odds ratio [OR] 3.0; 95% confidence interval [CI], 1.2-7.5 for LANA and OR 2.8; 95% CI, 1.3-6.0 for ORF 65) and hepatitis A virus (OR 2.2; 95% CI, 1.1-4.5 for ORF 65). KSHV-seropositive men reported nonsignificantly more casual sexual partners and were nonsignificantly more likely to report insertive oroanal contact with casual partners. These data suggest that KSHV might be sexually transmitted among homosexual men. Men were observed until October 1996 for development of KS. Those seropositive to either KSHV assay at baseline were more likely than the seronegative to develop KS during follow-up (rate ratio [RR] 4.4; 95% CI, 1.9-10.2). Of those seropositive for KSHV, 53% developed KS.

Demographic, dietary and lifestyle factors differentially explain variability in serum carotenoids and fat-soluble vitamins: baseline results from the sentinel site of the Olestra Post-Marketing Surveillance Study

Biochemical measures of nutrients or other dietary constituents can be an important component of nutritional assessment and monitoring. However, accurate interpretation of the nutrient concentration is dependent on knowledge of the determinants of the body pool measured. The purpose of this study was to identify the determinants of serum carotenoid and fat-soluble vitamin concentrations in a large, community-based sample (n = 1042). Multiple linear regression analysis was used to examine effects of demographic characteristics (age, sex, race/ethnicity, education), health-related behavior (exercise, sun exposure, smoking, alcohol consumption), and intake (diet, supplements) on serum retinol, 25-hydroxyvitamin D, alpha-tocopherol, phylloquinone, and carotenoid concentrations. Age, sex, race/ethnicity, vitamin A intake, and alcohol consumption were found to be determinants of serum retinol concentration. Race/ethnicity, vitamin D intake, body mass index, smoking status, and sun exposure were determinants of serum 25-hydroxyvitamin D concentration. Determinants of serum alpha-tocopherol were age, sex, race/ethnicity, alpha-tocopherol intake, serum cholesterol, percentage of energy from fat (inversely related), supplement use, and body mass index. Age, sex, phylloquinone intake, serum triglycerides, and supplement use were determinants of serum phylloquinone concentration. Primary determinants of serum carotenoids were age, sex, race/ethnicity, carotenoid intake, serum cholesterol, alcohol consumption, body mass index, and smoking status. Overall, the demographic, dietary, and other lifestyle factors explained little of the variability in serum concentrations of retinol (R2 = 0.20), 25-hydroxyvitamin D (R2 = 0.24), and the carotenoids (R2 = 0.15-0.26); only modest amounts of the variability in serum phylloquinone concentration (R2 = 0.40); and more substantial amounts of the variability in serum alpha-tocopherol concentration (R2 = 0.62).