Abacavir substitution for nucleoside analogs in patients with HIV lipoatrophy: a randomized trial

CONTEXT

Peripheral lipoatrophy may complicate antiretroviral therapy of human immunodeficiency virus (HIV) infection, often related to duration and type of nucleoside analog therapy, and may have a mitochondrial pathogenesis. No proven therapy exists for lipoatrophy, but abacavir is a nucleoside analog that may be less toxic to mitochondria.

OBJECTIVE

To determine if substitution of stavudine or zidovudine with abacavir improves HIV lipoatrophy without affecting control of HIV replication.

DESIGN

Randomized, open-label 24-week study.

SETTING

Seventeen hospital HIV outpatient clinics and primary care centers in Australia and England, with randomization from June 2000 through January 2001.

PARTICIPANTS

A total of 111 adults (109 men) with moderate or severe lipoatrophy who were receiving stavudine (n = 85) or zidovudine (n = 26) and had stable plasma HIV RNA levels below 400 copies/mL and no prior abacavir therapy.

INTERVENTION

Patients were randomly assigned to switch from stavudine or zidovudine to abacavir, 300 mg twice per day, while continuing all other antiretroviral therapy (n = 54) or to continue all antiretroviral therapy (n = 57).

MAIN OUTCOME MEASURES

The primary end point was limb fat mass, measured by dual-energy x-ray absorptiometry; key secondary end points were plasma HIV RNA levels, adverse events, physician-assessed (via subjective measures) lipodystrophy severity, total and central fat mass, and fasting metabolic (lipid, glycemic, and lactate) levels.

RESULTS

There was a significant increase in limb fat in the abacavir group relative to the stavudine/zidovudine group (0.39 vs 0.08 kg; mean difference, 0.31; 95% confidence interval [CI], 0.06-0.57 kg), as well as significant relative increases in subcutaneous thigh (P =.01), arm (P<.001), and abdominal (P =.001) fat areas on computed tomography. Switching had no significant effect on secondary end points, including plasma HIV RNA (for unadjusted comparison between groups at week 24, odds ratio, 1.38; 95% CI, 0.48-3.96). Change in limb fat mass at week 24 did not correlate with change in subjectively determined perceived lipoatrophy severity (r = -0.06; P =.53 by Spearman correlation). Hypersensitivity to abacavir was seen in 5 patients (10%).

CONCLUSIONS

In this sample of lipoatrophic HIV-infected adults, switching from stavudine or zidovudine to abacavir for 24 weeks led to significant, albeit modest, objectively measured increases in limb fat. Clinical lipoatrophy, as assessed subjectively, did not resolve, however, and at the rate of increase observed may take years to resolve with use of this strategy. Longer-term follow-up is needed.

Reversal of atherogenic lipoprotein profile in HIV-1 infected patients with lipodystrophy after replacing protease inhibitors by nevirapine

BACKGROUND

The widespread use of protease inhibitors (PI) has been associated with abnormalities in the lipid profile of HIV-1-infected patients. Treatment simplification approaches in which PI are replaced by nevirapine (NVP) have been shown to improve PI-related toxicity.

OBJECTIVE

To assess the impact on plasma lipids of replacing the PI by NVP in HIV-1 infected patients with lipodystrophy.

METHODS

We studied 34 patients with lipodystrophy who had been the first to be enrolled in a prospective, randomized trial of continuing current treatment, or replacing PI with NVP. Sixteen patients replaced their PI with NVP and 18 continued their current PI-containing treatment. Total, low density lipoprotein (LDL), very low density lipoprotein (VLDL), intermediate density lipoprotein and high density lipoprotein (HDL) cholesterol and triglyceride levels, the size and particle number of LDL were determined at baseline and after 24 weeks, by nucleic magnetic resonance spectroscopy.

FINDINGS

After 24 weeks of replacing the PI with NVP, we observed a reduction of total cholesterol (P = 0.028), LDL-cholesterol (P = 0.001), the number of circulating LDL particles (P = 0.003) and the VLDL-1 triglyceride level (P = 0.032). A concomitant significant increase was observed in both HDL-cholesterol level (P = 0.002) and HDL particle size (P < 0.001). No significant changes were observed in the group that continued taking the PI.

CONCLUSIONS

The replacement of PI by NVP improved the lipid profile both by reducing the number and lipid content of atherogenic LDL particles, and increasing the protective HDL fraction. Although total triglyceride levels remained unchanged, a reduction in the VLDL-1 fraction contributes to the reduction of LDL particles. These changes are expected to reduce the risk of cardiovascular disease in HIV-1-infected patients on highly active antiretroviral therapy.

Serum adiponectin and leptin levels in patients with lipodystrophies

Lipodystrophies are characterized by selective but variable loss of body fat and metabolic complications of insulin resistance. We hypothesized that reduced synthesis and secretion of adipocyte-specific proteins may be related to the metabolic complications of lipodystrophy. Therefore, we compared fasting serum concentrations of adiponectin and leptin, in 18 patients with congenital generalized lipodystrophy (CGL), 11 with acquired generalized lipodystrophy (AGL), 46 with familial partial lipodystrophy-Dunnigan variety (FPLD) and 18 with acquired partial lipodystrophy (APL) and studied their relationship to metabolic parameters. Patients with CGL and AGL had markedly reduced serum adiponectin levels compared to those with FPLD and APL (median [range]: 1.5 [0.4-7.5], 3.2 [0.6-7.7], 6.9 [1.9-23.2] and 7.9 [3.1-13.3] microg/mL, respectively, p < 0.0001); the same trend was noted for serum leptin levels (0.63 [0.05-3.7], 2.18 [0.05-11.30], 2.86 [0.23-9.00] and 6.24 [1.21-10.4] ng/mL, respectively, p < 0.0001). Serum adiponectin levels correlated negatively with fasting serum triglycerides (r = -0.6, p < 0.001) and insulin levels (r = -0.5, p < 0.0001) and positively with serum high-density lipoprotein cholesterol levels (r = 0.5, p < 0.001). Serum adiponectin levels were lower in patients with diabetes compared to non-diabetic subjects (3.0 vs. 7.1 microg/mL, p < 0.001). Our results indicate that serum adiponectin and leptin levels are extremely low in patients with generalized lipodystrophies and may be related to severe insulin resistance and its metabolic complications in lipodystrophies.

Triglyceride-induced diabetes mellitus in congenital generalized lipodystrophy

High levels of triglycerides and free fatty acids have been implicated in the pathogenesis of type 2 diabetes mellitus (DM). Congenital generalized lipodystrophy (CGL) is an autosomal recessive syndrome characterized by intense whole body reduction of subcutaneous fat. Its clinical manifestations appear during the first years of life. However, DM is usually a late event. We report a patient with CGL, diagnosed at 4 months of age, who has severe hypertriglyceridemia (serum triglyceride 12.34 mmol/l and cholesterol 3.90 mmol/l), muscular hypertrophy, hepatomegaly and DM (fasting glycemia 25.9 mmol/l). Hepatic biopsy revealed steatosis and fibrosis. A modified normolipidic (composed of medium chain triglycerides) normocaloric normoproteic milky diet and insulin therapy were instituted. After 1 month treatment a reduction of serum glucose and triglyceride levels (4.13 mmol/I and 7.7 mmol/l, respectively) was noted, with later normalization, which led to the discontinuation of insulin therapy. The patient has been maintaining good control with diet alone, presenting normal serum lipid levels (triglycerides 1.07 mmol/l, total cholesterol 2.71 mmol/l) and the following glycemic profile at OGTT: 0' 4.4 mmol/l; 30' 7.0 mmol/l; 60' 3.8 mmol/l; 90' 5.3 mmol/l, and 120' 5.2 mmol/l. The disappearance of hepatic steatosis was evidenced by a biopsy obtained 1 year after the beginning of treatment. In conolusion, this report suggests that the DM occurring in CGL can be precipitated by high triglyceride levels.

Characterization of adiposity and metabolism in Lmna-deficient mice

Dunnigan's Familial Partial Lipodystrophy (FPLD) is an autosomal dominant disease characterized by regional fat loss and insulin resistance. FPLD is caused by mutations in the LMNA gene, which encodes intermediate filaments of the nuclear lamina. Different LMNA mutations cause Emery-Dreifuss muscular dystrophy and/or a dilated cardiomyopathy. It is not known how LMNA mutations cause any of the disease phenotypes. Here we measure physical and metabolic characteristics of Lmna-/- and +/- mice to determine their usefulness as models for FPLD. Lmna-/- mice, which die prematurely of muscular dystrophy, have little fat, but do not show the insulin resistance characteristic of FPLD. Lmna+/- mice, despite treatment with a high fat diet, do not have decreased fat stores or metabolic features of FPLD. We also show, in mice, that Lmna transcripts are expressed at high levels in muscle and adipose tissue, but do not vary by body region or sex. In conclusion, Lmna+/- and -/- mice do not mimic Dunnigan's FPLD, and differential expression of lamins A and C does not appear to contribute to sex- or tissue-specific LMNA phenotypes.

Elevated concentrations of free fatty acids are associated with increased insulin response to standard glucose challenge in human immunodeficiency virus-infected subjects with fat redistribution

Fat redistribution, defined by both increased abdominal visceral fat and/or decreased abdominal, extremity, and facial subcutaneous fat, is increasingly recognized among human immunodeficiency virus (HIV)-infected patients treated with combination antiretroviral therapy. Fat redistribution in this population is associated with insulin resistance and dyslipidemia and is often referred to as the HIV lipodystrophy syndrome (LIPO). Fatty acids are known to modulate insulin resistance in other disease states, but a comprehensive evaluation of fatty acids has not been undertaken among HIV-infected patients with fat redistribution. In this study, we investigated fatty acid concentrations in 64 HIV-infected individuals (45 men and 19 women) with evidence of fat redistribution (LIPO) in comparison to 30 HIV-infected individuals (20 men and 10 women) without evidence of fat redistribution (NONLIPO) and 32 HIV-negative healthy control subjects (C) (21 males and 11 females) of similar age and body mass index (BMI). Glucose, insulin, and free fatty acid (FFA) levels were measured in response to a 75-g oral glucose tolerance test (OGTT) in the LIPO, NONLIPO, and C subjects. In addition, fasting lipids were obtained, and body composition was determined by anthropometric measurements and dual-energy x-ray absorptiometry (DXA). Fasting FFA concentrations were significantly increased in the LIPO group as compared with NONLIPO and C subjects (0.74 +/- 0.03 v 0.60 +/- 0.04 [mean +/- SEM] mmol/L, P =.002, LIPO v NONLIPO; 0.74 +/- 0.03 v 0.59 +/- 0.03 mmol/L, P =.001, LIPO v C). In contrast, fasting FFA concentrations were not increased in the NONLIPO group (0.60 +/- 0.04 v 0.59 +/- 0.03, P =.909, NONLIPO v C). Similarly, fasting triglycerides and 120-minute OGTT FFA were significantly increased in the LIPO group as compared with the NONLIPO and C group. FFA decreased in HIV-infected LIPO, NONLIPO, and C subjects in response to OGTT, but the 120-minute FFA concentrations remained significantly elevated in LIPO patients compared with NONLIPO and C subjects. In a multivariate regression model of LIPO patients, fasting FFA (P =.027) was a strong independent predictor of insulin area under the curve (AUC), controlling for age, BMI, gender, and body composition (r(2) for model =.31). No differences were observed in FFA concentrations in the LIPO group in an analysis based on current protease inhibitor (PI) use. These data suggest that FFA concentrations are increased in HIV-infected patients with fat redistribution. Increased fasting concentrations of fatty acids are associated with abnormal insulin responses to standard glucose challenge in HIV-infected patients with fat redistribution. Further studies are necessary to determine the mechanism of increased fatty acid concentrations and the role played by increased FFA in mediating insulin resistance in this population.

Increased serum interferon alpha in HIV-1 associated lipodystrophy syndrome

BACKGROUND

A syndrome of lipodystrophy (LD) associated with peripheral lipoatrophy and central/visceral adiposity has been reported in HIV-1-infected patients treated by combined antiretroviral therapy (ART). Lipid metabolism is partly regulated by both steroid hormones and cytokines and we have previously reported that dyslipidaemia in LD-positive men is correlated to an increase in cortisol : DHEA ratio (Christeff et al., AIDS 1999;13:2251). In this study we questioned whether it is also related to cytokine perturbations.

MATERIALS AND METHODS

A cross-sectional study was performed on 42 HIV-1-positive men on ART, 27 of whom had symptoms of LD, defined by computed tomography scan. Serum cytokines (IFN-alpha, TNF-alpha, sTNF-RI, sTNF-RII, IL-6, IL-1beta and IL-2) and lipids [cholesterol, triglycerides (TG) and their subclasses], and apolipoproteins (Apo), were determined.

RESULTS

Serum IFN-alpha was markedly increased in LD-positive compared with LD-negative men and controls. IL-6 and TNF-alpha concentrations were also significantly elevated in HIV-positive men compared to controls but the levels of these cytokines did not differ between the two groups of patients. A significant positive correlation was found between accumulation of IFN-alpha and increased levels of cholesterol, TG, VLDL cholesterol, VLDL TG, ApoB and ApoB-ApoA1 ratio. A multivariate forward-performed analysis revealed that IFN-alpha is the best marker for lipid perturbations associated to LD, followed by insulin and cortisol : DHEA ratio.

CONCLUSIONS

This study demonstrates an association between serum IFN-alpha and lipid alterations in LD-positive men. The concomittant action of IFN-alpha and cortisol : DHEA ratio is probably one of the mechanisms responsible for hyperlipidaemia in LD syndrome.

Does race protect an oriental population from developing lipodystrophy in HIV-infected individuals on HAART?

OBJECTIVES

Lipodystrophy, hyperlipidaemia and hyperinsulinaemia are common metabolic complications of highly active antiretroviral therapy (HAART) in human immunodeficiency virus (HIV)-infected Caucasians. We questioned whether such complications also occur in other races.

METHODS

A cross-sectional analysis was performed in an outpatient clinic of a university teaching hospital with 156 Koreans, divided into HIV-infected subjects receiving HAART (n=57, group 1), HAART-naïve subjects (n=42, group 2), and healthy controls (n=57, group 3). Lipodystrophy was assessed by physical examination and questionnaire and body composition by dual-energy X-ray absorptiometry. Fasting triglyceride, total cholesterol, low-density (LDL) and high-density lipoprotein (HDL) cholesterol, free fatty acid (FFA), Apolipoprotein A1 (ApoA1), Apolipoprotein B (ApoB), glucose, insulin, c-peptide, leptin, cortisol, dehydroepiandrosterone (DHEA), CD4, CD8 lymphocyte counts and HIV RNA load were measured.

RESULTS

Lipodystrophy was observed in only 3.5% of HAART-treated HIV-infected Koreans. No statistical difference in regional fat accumulation or peripheral fat wasting was observed between groups 1, 2 and 3. No statistical difference in triglyceride, total cholesterol, LDL cholesterol, FFA, ApoA1, ApoB, glucose, insulin, C-peptide, leptin, cortisol, and DHEA were observed between groups 1, 2 and 3. HDL cholesterol was significantly lower in HIV-infected individuals compared to controls.

CONCLUSIONS

Lipodystrophy, hyperlipidaemia, and insulin resistance are rare metabolic complications of HAART in an oriental HIV-infected group of individuals. These findings warrant further race-specific metabolic complication studies in HIV-infected subjects receiving HAART.

Leptin and adipose tissue maldistribution in HIV-infected male patients with predominant fat loss treated with antiretroviral therapy

BACKGROUND

Metabolic disturbances and fat maldistribution are main features of the antiretroviral-related lipodystrophy syndrome (LDS). Different phenotypes of fat distribution abnormalities can be observed: fat loss, fat accumulation, or a mixed pattern. In patients with predominant loss of fat, the roles of leptin, lipids, and glucose homeostasis disturbances have not yet been clearly established.

METHODS

The study comprised 34 HIV-infected male patients receiving antiretroviral treatment that included protease inhibitors. A lipoatrophic phenotype, defined as fat loss in face or extremities, both normal weight and waist:hip ratio, and absence of fat accumulation elsewhere, was present in all cases. Fat distribution disturbances were confirmed by abdominal and midthigh computed tomography-calculated adipose tissue content. Fasting plasma glucose, insulin, proinsulin, total leptin, testosterone, and lipid profiles were measured. After 2 hours, 75-g oral glucose tolerance test (OGTT), glucose, insulin, and proinsulin levels were also obtained. Insulin resistance was calculated using the homeostasis model assessment for insulin resistance (HOMA-r) method. Both healthy study subjects ( n = 385) and antiretroviral-naive HIV-positive patients ( n = 13) were used as controls.

RESULTS

Of these LDS patients, 5.8% showed diagnostic criteria for diabetes and 17.8% for impaired glucose tolerance. A lipid pattern characterized by high total cholesterol and high low density lipoprotein (LDL) plasma levels, hypertriglyceridemia, and normal high density lipoprotein (HDL) levels was observed. Fasting insulin and 2-hour post OGTT insulin levels, and insulin resistance index were significantly higher in LDS patients than in antiretroviral-naive HIV-positive patients. Plasma leptin levels were significantly lower in lipoatrophic patients than in healthy control individuals. Patients with LDS presented with significant midthigh fat reduction and visceral fat accumulation compared with findings in antiretroviral-naive HIV-positive patients. A significant correlation was found between plasma leptin levels and midthigh fat content.

CONCLUSION

Peripheral fat loss in extremities in LDS patients with lipoatrophic phenotype is also associated with low plasma leptin levels, visceral fat accumulation, and metabolic disturbances related to an increased cardiovascular risk. In LDS patients, plasma leptin levels could be a marker of subcutaneous adipose tissue content.

A novel heterozygous mutation in peroxisome proliferator-activated receptor-gamma gene in a patient with familial partial lipodystrophy

Familial partial lipodystrophies (FPL) are a heterogeneous group of genetic disorders characterized by marked loss of subcutaneous (sc) fat from the extremities. Affected individuals show an increased preponderance of insulin resistance, diabetes mellitus and dyslipidemia. Recently, lamin A/C gene mutations were found in patients with FPL, Dunnigan variety. However, the genetic basis of other phenotypes remains unknown. We studied peroxisome proliferator-activated receptor-gamma (PPARgamma) gene as a candidate gene in seven FPL patients who did not appear to have Dunnigan variety. Analysis of the coding region of PPARG revealed C to T heterozygous mutation at nucleotide 1273 in exon 6 which changes a highly conserved residue, arginine at position 425 to cysteine (R425C) in the patient FX200.21. The patient is a 64-year-old nonHispanic white woman who developed diabetes mellitus and hypertriglyceridemia at age 32 years and lipodystrophy of the extremities and face at age 50 years. She also had hirsutism. Anthropometry and whole body magnetic resonance imaging revealed marked loss of sc fat particularly from the extremities but sc truncal fat was slightly increased. None of the four unaffected family members harbored the mutation. We conclude that heterozygous, R425C, mutation in PPARG could be the molecular basis for one of the familial partial lipodystrophy phenotypes.

Antiretroviral treatment simplification with nevirapine in protease inhibitor-experienced patients with hiv-associated lipodystrophy: 1-year prospective follow-up of a multicenter, randomized, controlled study

BACKGROUND

Simpler and less toxic antiretroviral strategies are needed to maximize treatment compliance without sacrificing potency, at least for drug-experienced HIV-infected patients currently on regimens containing protease inhibitors (PIs). Small nonrandomized studies have suggested a beneficial role of PI-sparing regimens on lipodystrophy.

OBJECTIVES

To assess the virologic, immunologic, and clinical benefit of switching the PI to nevirapine in patients with HIV-associated lipodystrophy and sustained viral suppression before entry in the study.

DESIGN

Open-labeled, prospective, randomized, multicenter study.

SETTING

Seven reference inpatient centers for HIV/AIDS in Spain.

PATIENTS

One hundred six HIV-infected adults with clinically evident lipodystrophy who sustained HIV-RNA suppression for at least 6 months with PI-containing antiretroviral combinations.

INTERVENTION

Replacement of the PI with nevirapine during 48 weeks (Group A) versus continuing the prior PI (Group B).

MEASUREMENTS

Several virologic and immunologic analyses, standard and specific biochemical tests, and anthropometric and dual X-ray absorptiometry measurements.

RESULTS

At week 48, an HIV-1 RNA level <400 copies/ml was maintained in 79% and 77% of patients in Groups A and B, respectively, whereas 74% and 72% of patients had viral load levels <50 copies/ml. Absolute CD4+ counts significantly increased in both groups compared with baseline values, and a significant decrease in CD38+CD8+ cells was observed in Group A (p <.01) but not in group B. Overall, no significant changes in anthropometric or body shape measurements were found after 48 weeks. Fasting total cholesterol and triglyceride levels decreased in Group A (but not in Group B) compared with baseline values (p <.05), although no significant differences were seen between groups at the end of the study. Subjects in Group A reported a better quality of life (QOL) index than controls (p <.001), with the main reason reported being the greater simplicity of the new drug regimen.

CONCLUSIONS

Protease inhibitor-sparing regimens, including nevirapine, seem to be an effective alternative for PI-experienced patients. Nevirapine-based triple therapies allow maintained control of HIV-1 RNA levels and improve the immunologic response at 48 weeks of follow-up in patients with prior sustained virologic suppression. The switch to nevirapine significantly improved the lipidic profile in Group A, although there were no differences between groups at the end of the study. Additionally, no significant changes were seen in terms of lipodystrophy-related body shape changes 1 year after the PI substitution. Finally, nevirapine-containing regimens have a simpler dosing schedule, and this facilitates high adherence and improves QOL.

Lipodystrophy syndrome in children infected with human immunodeficiency virus

Lipodystrophy syndrome (LDS), a fat-wasting condition commonly reported in adults infected with human immunodeficiency virus (HIV), has been linked to the use of antiretroviral agents. Recently, LDS was observed in children infected with HIV Little is known about the pathophysiology of this condition, although it is believed that LDS has many causes and modes of presentation. Even less is known about what long-term effects LDS will have on HIV-infected patients. Three patients who developed LDS were observed in a pediatric HIV clinic. Due to the lack of knowledge about the condition's natural course and the benefits versus risks of treatment, they were not treated specifically for LDS. Their lipid profiles, however, continue to be monitored closely twice/year.

Assessment of growth hormone dynamics in human immunodeficiency virus-related lipodystrophy

Human immunodeficiency virus (HIV) lipodystrophy (LIPO) is characterized by increased visceral adiposity, peripheral fat atrophy, dyslipidemia, and insulin resistance. GH concentrations are known to vary inversely with excess weight and body fat but have not been investigated in HIV lipodystrophy. Twenty-one subjects with HIV LIPO, 20 HIV-infected nonlipodystrophy subjects (NONLIPO), and 20 control (C) subjects were prospectively recruited for this study and compared. Subjects in the three groups were all male, age-matched [median, 47 yr old (interquartile range, 37-50) LIPO; 41 (37-44) NONLIPO; and 43 (37-49) C], and body mass index-matched [median, 24.3 kg/m(2) (interquartile range, 22.2-26.6) LIPO; 24.4 (23.3-25.9) NONLIPO; and 24.8 (22.7-26.1) C] (P: > 0.05 for all comparisons). Visceral abdominal fat [16,124 mm(2) (11,246-19,790) LIPO; 7,559 (5,134-11,201) NONLIPO; and 8,803 (6,165-11,623) C; P < 0.01 LIPO vs. NONLIPO and LIPO vs. C] and the ratio of visceral abdominal fat to sc abdominal fat [1.37 (0.71-2.44) LIPO vs. 0.57 (0.47-0.78) NONLIPO vs. 0.55 (0.41-0.71) C, P < 0.01 LIPO vs. NONLIPO and LIPO vs. C] were significantly increased in the LIPO subjects but were not significantly different between NONLIPO and C. The mean overnight GH concentration, determined from frequent sampling every 20 min (from 2000 h to 0800 h) was decreased in the LIPO subjects [0.38 microg/L (0.13-0.67) LIPO vs. 0.96 (0.53-1.30) NONLIPO vs. 0.81 (0.49-1.03) C, P < 0.05 LIPO vs. NONLIPO and LIPO vs. C] and not significantly different between NONLIPO and C. Pulse analysis demonstrated decreased baseline GH [0.08 microg/L (0.06-0.21) LIPO vs. 0.19 (0.10-0.32) NONLIPO vs. 0.17 (0.12-0.57) C, P < 0.05 LIPO vs. NONLIPO and LIPO vs. C] and GH peak amplitude [1.06 microg/L (0.46-1.94) LIPO vs. 2.47 (1.22-3.43) NONLIPO and 2.27 (1.36-4.25) C, P < 0.05 LIPO vs. NONLIPO and LIPO vs. C] in the LIPO subjects but no significant difference in pulse frequency. No significant differences were observed between NONLIPO and C for any GH parameter. Insulin-like growth factor-I was not different between the groups. Total body fat (r = -0.40, P = 0.01) and visceral fat (r = -0.58, P = 0.0001) correlated inversely with mean overnight GH concentrations in the HIV-infected patients. In a multivariate regression model, controlling for age, body mass index, body fat, and visceral fat, only visceral fat was a significant predictor of mean GH concentrations (P = 0.0036, r(2) for model = 0.40). These data demonstrate normal GH pulse frequency and insulin-like growth factor-I concentrations but reduced mean GH concentrations, basal GH concentrations, and GH pulse amplitude in patients with HIV lipodystrophy. Increased visceral adiposity is the strongest predictor of reduced GH concentrations in HIV lipodystrophy. Further studies are necessary to determine the clinical significance of reduced GH in patients with HIV lipodystrophy.

Metabolic abnormalities and cardiovascular disease risk factors in adults with human immunodeficiency virus infection and lipodystrophy

We evaluated metabolic and clinical features of 71 HIV-infected patients with lipodystrophy by comparing them with 213 healthy control subjects, matched for age and body mass index, from the Framingham Offspring Study. Thirty HIV-infected patients without fat redistribution were compared separately with 90 matched control subjects from the Framingham Offspring Study. Fasting glucose, insulin, and lipid levels; glucose and insulin response to standard oral glucose challenge; and anthropometric measurements were determined. HIV-infected patients with lipodystrophy demonstrated significantly increased waist-to-hip ratios, fasting insulin levels, and diastolic blood pressure compared with controls. Patients with lipodystrophy were more likely to have impaired glucose tolerance, diabetes, hypertriglyceridemia, and reduced levels of high-density lipoprotein (HDL) cholesterol than were controls. With the exception of HDL cholesterol level, these risk factors for cardiovascular disease (CVD) were markedly attenuated in patients without lipodystrophy and were not significantly different in comparison with controls. These data demonstrate a metabolic syndrome characterized by profound insulin resistance and hyperlipidemia. CVD risk factors are markedly elevated in HIV-infected patients with fat redistribution.

Apoprotein c-III and E-containing lipoparticles are markedly increased in HIV-infected patients treated with protease inhibitors: association with the development of lipodystrophy

Long-term therapy with protease inhibitors (PIs) can induce hypertriglyceridemia and development of a lipodystrophy. To better understand these metabolic alterations, the apoprotein and lipoparticle profile was investigated in male HIV patients under antiretroviral therapy: 49 received PIs, and 14 were given only two reverse transcriptase inhibitors. As controls, 63 male subjects were selected from a population study carried out in the Toulouse, France, area. Fasting glucose, insulin, and C-peptide were also determined. All patients under PIs displayed low levels of plasma glucose and increased insulin. PI administration was associated with moderate hypertriglyceridemia, low high-density cholesterol and apolipoprotein (apo) A-I levels. The most striking changes were a 2- to 3-fold increase in apo E and apo C-III, essentially recovered as associated to apo B-containing lipoparticles. Levels of those lipoparticles were two to eight times above control values. About 50% of PI-treated patients had developed a patent lipodystrophy. Multivariate analysis revealed that, among the investigated parameters, apo C-III was the only one found strongly associated with the occurrence of lipodystrophy (odds ratio, 5.5; P: < 0.015). Finally, 13 PI-receiving subjects with patent hypertriglyceridemia were given fenofibrate and were reevaluated 2 months later. Triglycerides, apo E, apo C-III, and the corresponding lipoparticles had returned to nearly normal levels. These results document the accumulation of potentially atherogenic lipoparticles under PIs. Apo C-III may play a pivotal role in the development of hypertriglyceridemia and lipodystrophy.

Hyperandrogenemia in human immunodeficiency virus-infected women with the lipodystrophy syndrome

A novel lipodystrophy syndrome characterized by insulin resistance, hypertriglyceridemia, and fat redistribution has recently been described in human immunodeficiency virus (HIV)-infected men and women. Women with the HIV lipodystrophy syndrome exhibit a marked increase in waist-to-hip ratio and truncal adiposity; however, it is unknown whether androgen levels are increased in these patients. In this study, we assessed androgen levels in female patients with clinical lipodystrophy based on evidence of significant fat redistribution in the trunk, extremities, neck and/or face (LIPO: n = 9; age, 35.7+/-1.7 yr; BMI, 24.7+/-0.8 kg/m2) in comparison with age- and BMI-matched nonlipodystrophic HIV-infected females (NONLIPO: n = 14; age, 37.6+/-1.1 yr; BMI, 23.4+/-0.6 kg/m2) and healthy non-HIV-infected control subjects (C: n = 16; age, 35.8+/-0.9 yr; BMI, 23.1+/-0.4 kg/m2). Fasting insulin, lipid levels, virologic parameters, and regional body composition using dual energy x-ray absorptiometry were also assessed. Total testosterone [ LIPO, 33+/-6 ng/dL (1.1+/-0.2 nmol/L); NONLIPO, 17+/-2 ng/dL (0.6+/-0.1 nmol/L); C, 23+/-2 ng/dL (0.8+/-0.1 nmol/L); P < 0.05 LIPO vs. C and LIPO vs. NONLIPO] and free testosterone determined by equilibrium dialysis [LIPO, 4.5+/-0.9 pg/mL (16+/-3 pmol/L); NONLIPO, 1.7+/-0.2 pg/mL (6+/-1 pmol/L); C, 2.4+/-0.2 pg/mL (8+/-1 pmol/L); P < 0.05 LIPO vs. C and LIPO vs. NONLIPO] were increased in the lipodystrophic patients. Sex hormone-binding globulin levels were not significantly different between LIPO and C, but were significantly lower in the LIPO vs. NONLIPO patients (LIPO 84+/-7 vs. NONLIPO 149+/-17 nmol/L, P < 0.05). The LH/FSH ratio was significantly increased in the LIPO group compared with the NONLIPO and C subjects (LIPO, 2.0+/-0.6; NONLIPO, 1.1+/-0.1; C, 0.8+/-0.1; P < 0.05 LIPO vs. NONLIPO and LIPO vs. C). Body fat distribution was significantly different between LIPO and C subjects. Trunk to extremity fat ratio (1.46+/-0.17 vs. 0.75+/-0.05, LIPO vs. C, P < 0.05) was increased and extremity to total fat ratio decreased (0.40+/-0.03 vs. 0.55+/-0.01, LIPO vs. C, P < 0.05). In contrast, fat distribution was not different in the NONLIPO group vs. control subjects. Among the HIV-infected patients, free testosterone correlated with percent truncal fat (trunk fat/trunk mass) (r = 0.43, P = 0.04). These data suggest that hyperandrogenemia is another potentially important feature of the HIV-lipodystrophy syndrome in women. Additional studies are necessary to determine the clinical significance of increased androgen levels and the relationship of hyperandrogenism to fat redistribution and insulin resistance in this population of patients.

LMNA R482Q mutation in partial lipodystrophy associated with reduced plasma leptin concentration

Mutations in LMNA, which encodes lamins A and C, have been found in patients with autosomal dominant Dunnigan-type familial partial lipodystrophy (FPLD). We analyzed the relationship between plasma leptin and the rare LMNA R482Q mutation in 23 adult FPLD subjects compared with 25 adult family controls with normal LMNA in an extended Canadian FPLD kindred. We found that the LMNA Q482/R482 genotype was a significant determinant of plasma leptin, the ratio of plasma leptin to body mass index (BMI), plasma insulin, and plasma C peptide (P= 0.015, P = 0.0007, P = 0.0004, and P < 0.0001, respectively), but not BMI (P = 0.67). Family members who were heterozygous for LMNA Q482/R482 had significantly lower plasma leptin and leptin:BMI ratio than unaffected R482/R482 homozygotes. Fasting plasma concentrations of insulin and C peptide were both significantly higher in LMNA Q482/R482 heterozygotes than in R482/R482 homozygotes. Multivariate regression analysis revealed that the LMNA R482Q genotype accounted for 40.9%, 48.2%, 86.9%, and 81.0%, respectively, of the attributable variation in log leptin, leptin:BMI ratio, log insulin, and log C peptide (P = 0.013, P = 0.0007, P = 0.0002 and P < 0.0001, respectively). The results indicate that a rare FPLD mutation in LMNA determines the plasma leptin concentration. It remains to be established whether the reduction in leptin results from the reduced adipose tissue mass in FPLD or from another subcellular effect of mutant LMNA. It also remains to be established whether the insulin resistance in FPLD is a consequence of the reduced plasma leptin or of another functional change resulting from mutant LMNA.

HIV-1 protease inhibitors induce an increase of triglyceride level in HIV-infected men without modification of insulin sensitivity: a longitudinal study

We investigated longitudinally the effect of protease inhibitors (PI) on insulin sensitivity, glycemia, and serum lipids in HIV-infected patients. Ninety-one consecutive patients treated with PI for at least 12 months were included in this study. Fasting glycemia, lipid profile, insulinemia, CD4 T lymphocytes, and plasma HIV-1 RNA were performed at baseline and on PI therapy. Insulin sensitivity and insulin secretion were measured by the homeostasis model assessment (HOMA MODEL) using the fasting glucose and insulin concentrations. Triglycerides (+ 0.34 mmol/l, SD = 1.07, p = 0.001) and cholesterol (+ 1.07 mmol/l, SD = 1.21, p= 0.001) significantly increased on PI therapy. Fasting glycemia, insulin sensitivity, and insulin secretion were not modified after PI therapy. PI therapy significantly increased body mass index (0.35 kg/m2, p < 0.05). Serum lipid changes correlated with changes in the CD4+ cell count. Lipodystrophy was observed in 40.6% of patients treated with PI. Our longitudinal study found that PI therapy had no major impact on fasting glycemia, insulin sensitivity, and insulin secretion. These findings are not consistent with previous cross-sectional studies, which did not include baseline measurements before PI initiation. However, we observed a similar profile of lipid changes induced by PI therapy. These results suggest that PI could be responsible for the development of hypertriglyceridemia by a mechanism independent of insulin resistance which remains to be elucidated.

Efficacy and safety of troglitazone in the treatment of lipodystrophy syndromes

BACKGROUND

Troglitazone promotes adipocyte differentiation in vitro and increases insulin sensitivity in vivo. Therefore, troglitazone may have therapeutic benefit in lipoatrophic diabetes.

OBJECTIVE

To determine whether troglitazone ameliorates hyperglycemia and hypertriglyceridemia or increases fat mass in lipoatrophic patients.

DESIGN

Open-labeled prospective study.

SETTING

United States and Canada.

PATIENTS

20 patients with various syndromes associated with lipoatrophy or lipodystrophy.

INTERVENTION

6 months of therapy with troglitazone, 200 to 600 mg/d.

MEASUREMENTS

Levels of hemoglobin A1c triglycerides, free fatty acids, and insulin; respiratory quotient; percentage of body fat; liver volume; and regional fat mass.

RESULTS

In the 13 patients with diabetes who completed 6 months of troglitazone therapy, hemoglobin A1c levels decreased by a mean of 2.8% (95% CI, 1.9% to 3.7%; P < 0.001). In all 19 study patients, fasting triglyceride levels decreased by 2.6 mmol/L (230 mg/dL) (CI, 0.7 to 4.5 mmol/L [62 to 398 mg/dL]; P = 0.019) and free fatty acid levels decreased by 325 micromol/L (CI, 135 to 515 micromol/L; P = 0.035). The respiratory quotient decreased by a mean of 0.12 (CI, 0.08 to 0.16; P < 0.001), suggesting that troglitazone promoted oxidation of fat. Body fat increased by a mean of 2.4 percentage points (CI, 1.3 to 4.5 percentage points; P = 0.044). Magnetic resonance imaging showed an increase in subcutaneous adipose tissue but not in visceral fat. In one patient, the serum alanine aminotransferase level increased eightfold during the 10th months of troglitazone treatment but normalized 3 months after discontinuation of treatment Liver biopsy revealed an eosinophilic infiltrate, suggesting hypersensitivity reaction as a cause of hepatotoxicity.

CONCLUSION

Troglitazone therapy improved metabolic control and increased body fat in patients with lipoatrophic diabetes. The substantial benefits of troglitazone must be balanced against the risk for hepatotoxicity, which can occur relatively late in the treatment course.

Barraquer-Simons lipodystrophy, Raynaud's phenomenon and cutaneous vasculitis

We report a 32-year-old man who presented with a 2-year history of unexplained weight loss and symptoms of Raynaud's phenomenon. Clinical examination and investigations were consistent with a diagnosis of acquired partial lipodystrophy (Barraquer-Simons disease). This patient also exhibited an associated cutaneous vasculitis and peripheral perniotic changes. He had normal renal function and glucose tolerance and no immunological abnormality has been detected in his serum to date. The absence of C3-nephritic factor in the presence of overt lipodystrophy suggests that there may be another factor or immunological mediator responsible for the subcutaneous changes seen in patients with lipodystrophy.

[A further case of analbuminemia]

At routine follow-up a 23-year-old female presented a high erythrocyte sedimentation rate and handicapping lipodystrophy of the lower limbs. Protein electrophoresis showed absence of an albumin peak and the diagnosis of analbuminaemia was therefore proposed. Investigation of family members disclosed that one brother out of a total of four siblings also had analbuminaemia. The hereditary pathway often appears to be autosomalrecessive. Subsequent review of the literature revealed only 28 other observed cases, although today electrophoresis has become a worldwide routine examination. Surprisingly, the almost complete absence of so important a protein as albumin does not trigger disease. The body is able to compensate for the lack of albumins with other proteins. The absence of abumin is typically associated with hyperlipidaemia and lipodystrophy in the female sex.

Lipodystrophy associated with protease inhibitors

Lipodystrophies, characterized by reduction of subcutaneous fat over part or all of the body surface, are uncommon. Their causes are unknown. Recently, lipodystrophy has been reported in human immunodeficiency virus (HIV)-infected patients taking protease inhibitors, which have been recommended since 1996 as standard therapy for HIV disease in combination with nucleoside analogues. In these cases, lipodystrophy consists of an association of peripheral lipoatrophy with central adiposity. We report four HIV-infected men on protease inhibitors who developed a disfiguring lipodystrophy. In three of them, the protease inhibitor was administered for a mean duration of 21.5 months (range 19-23) with good immunological and virological responses. Patient 4 had been treated for 2 years with successive combinations of protease inhibitors with nucleoside analogues without success. The four patients progressively developed an increase in abdominal girth associated with fat wasting of the face and legs. Two of them had recurrent paronychia of the great toes. Triglyceride levels were moderately increased in all patients, and one had a slightly increased cholesterol level. One patient had elevated glucose and insulin plasma levels during a glucose tolerance test. In two patients, a deep biopsy taken from the thigh showed thinning of the subcutaneous fat without other morphological changes. Computed tomographic scans of the face and abdomen confirmed the loss of almost all subcutaneous fat of the cheek and temporal regions, and abdominal perivisceral fat accumulation. For patients 1-3, the protease inhibitor was replaced by a non-nucleoside reverse transcriptase inhibitor. Nine months later, dysmorphic changes had not regressed, but lipid abnormalities had returned to normal and the paronychia had disappeared.