Inaccurate glycosylated hemoglobin A1C measurements in human immunodeficiency virus-positive patients with diabetes mellitus

What Is the Influence of HIV Serostatus on HbA1c? A Prospective Analysis Using Continuous Glucose Monitoring

OBJECTIVE

Type 2 diabetes (T2D) is reported to be more common in people living with HIV (PLWH). Clinical guidelines recommend screening for diabetes in PLWH, but there is no agreed method due to studies reporting HbA1c is falsely low in PLWH. These studies were performed in the early HIV era when participants were taking older preparations of antiretroviral therapy that are rarely used today. We aimed to investigate whether HIV serostatus influences HbA1c.

RESEARCH DESIGNS AND METHODS

We conducted a prospective cohort study of PLWH and age- and sex-matched HIV-negative participants who were purposely recruited from clinics in Brighton, U.K. Each participant wore a Dexcom G6 continuous glucose monitor (CGM) for up to 10 days, had glucose measured during an oral glucose tolerance test, and fructosamine and paired HbA1c were measured. We performed regression analysis to assess the influence of HIV on HbA1c and used a separate model for CGM glucose, venous glucose, and fructosamine. In addition, we included predictor variables used in previous studies that explored HbA1c discrepancy.

RESULTS

We recruited 60 PLWH (90% men, 50% with T2D, mean ± SD age 57 ± 10.7 years, 100% undetectable viral load) and 48 people without HIV (92% men, 30% with T2D, mean age 57.7 ± 8.9 years). We found that HIV serostatus did not have a significant influence on HbA1c within the regression models.

CONCLUSIONS

We performed a comprehensive assessment of glycemia to assess whether HIV serostatus influences HbA1c. We did not find any strong evidence that HIV serostatus influenced HbA1c. The results of our study support incorporating HbA1c into routine clinical blood work in PLWH.

HIV and type 2 diabetes: An evolving story

INTRODUCTION

Diabetes is widely reported to be more common in people living with HIV (PLWH). Much of the data supporting this originated during the earlier HIV era. The perceived increased risk of type 2 diabetes is reflected in HIV clinical guidelines that recommend screening for diabetes in PLWH on anti-retroviral therapy (ART). However, international HIV clinical guidelines do not agree on the best marker of glycaemia to screen for diabetes. This stems from studies that suggest HbA1c underestimates glycaemia in PLWH.

METHODS

Within this review we summarise the literature surrounding the association of HIV and type 2 diabetes and how this has changed over time. We also present the evidence on HbA1c discrepancy in PLWH.

CONCLUSION

We suggest there is no basis to any international guidelines to restrict HbA1c based on HIV serostatus. We recommend, using the current evidence, that PLWH should be screened annually for diabetes in keeping with country specific guidance. Finally, we suggest future work to elucidate phenotype and natural history of type 2 diabetes in PLWH across all populations.

Falsely Decreased HbA1c in a Type 2 Diabetic Patient Treated with Dapsone

OBJECTIVE

To discuss a case of a falsely low hemoglobin A1c (HbA1c) in a transplant patient treated with dapsone and its implications. HbA1c is widely used as a measure of glycemic control in diabetic patients. With the increasing transplant population, it is important to be mindful of medications used in this population that can affect HbA1c and to use other measures of glycemic control to guide treatment decisions.

METHODS

We present details of the case and review the relevant literature.

RESULTS

A 61-year-old patient received a liver transplant in 2012 and subsequently was noted to have a falling HbA1c despite evidence of hyperglycemia based on fingerstick glucose and fructosamine measurements. Review of the medical records revealed that the discordance between HbA1c and fingerstick glucose levels developed after initiation of dapsone therapy. Dapsone may lead to a falsely low HbA1c via several mechanisms. Upon cessation of dapsone therapy, the patient's HbA1c returned to pre-dapsone levels.

CONCLUSION

It is important to be aware of medications commonly used in transplant patients that may lead to a falsely low HbA1c level so that incorrect treatment decisions are not made. Fructosamine correlates with HbA1c and can be used as a measure of glycemic control in transplant patients when HbA1c cannot be used.

Endocrinological aspects of HIV infection

PURPOSE

Patients with human immunodeficiency virus (HIV) are living longer with effective antiretroviral therapies and are enjoying near normal life span. Therefore, they are encountering endocrine issues faced by the general population along with those specific to HIV infection. The purpose of this article is to review the common endocrine aspects of HIV infection, and the early detection and management strategies for these complications.

METHODS

Recent literature on HIV and endocrine disease was reviewed.

RESULTS

HIV can influence endocrine glands at several levels. Endocrine glandular function may be altered by the direct effect of HIV viral proteins, through generation of systemic and local cytokines and the inflammatory response and via glandular involvement with opportunistic infections and HIV-related malignancies. Endocrine disorders seen in people with HIV include metabolic issues related to obesity such as diabetes, hyperlipidemia, lipohypertrophy, lipoatrophy and lipodystrophy and contribute significantly to quality of life, morbidity and mortality. In addition, hypogonadism, osteopenia and osteoporosis are also more prevalent in the patients with HIV. Although disorders of hypothalamic-pituitary-adrenal axis resulting in adrenal insufficiency can be life threatening, these along with thyroid dysfunction are being seen less commonly in the antiretroviral therapy (ART) era. ARTs have greatly improved life expectancy in people living with HIV but can also have adverse endocrine effects.

CONCLUSIONS

Clinicians need to have a high index of suspicion for endocrine abnormalities in people with HIV as they can be potentially life threatening if untreated. Endocrine evaluation should be pursued as in the general population, with focus on prevention, early detection and treatment to improve quality of life and longevity.

Noncommunicable diseases among HIV-infected persons in low-income and middle-income countries: a systematic review and meta-analysis

OBJECTIVE

To appropriately identify and treat noncommunicable diseases (NCDs) among persons living with HIV (PLHIV) in low-and-middle-income countries (LMICs), it is imperative to understand the burden of NCDs among PLHIV in LMICs and the current management of the diseases.

DESIGN

Systematic review and meta-analysis.

METHODS

We examined peer-reviewed literature published between 1 January 2010 and 31 December 2016 to assess currently available evidence regarding HIV and four selected NCDs (cardiovascular disease, cervical cancer, depression, and diabetes) in LMICs with a focus on sub-Saharan Africa. The databases, PubMed/MEDLINE, Cochrane Review, and Scopus, were searched to identify relevant literature. For conditions with adequate data available, pooled estimates for prevalence were generated using random fixed effects models.

RESULTS

Six thousand one hundred and forty-three abstracts were reviewed, 377 had potentially relevant prevalence data and 141 were included in the summary; 57 were selected for quantitative analysis. Pooled estimates for NCD prevalence were hypertension 21.2% (95% CI 16.3-27.1), hypercholesterolemia 22.2% (95% CI 14.7-32.1), elevated low-density lipoprotein 23.2% (95% CI 15.2-33.6), hypertriglyceridemia 27.2% (95% CI 20.7-34.8), low high-density lipoprotein 52.3% (95% CI 35.6-62.8), obesity 7.8% (95% CI 4.3-13.9), and depression 24.4% (95% CI 12.5-42.1). Invasive cervical cancer and diabetes prevalence were 1.3-1.7 and 1.3-18%, respectively. Few NCD-HIV integrated programs with screening and management approaches that are contextually appropriate for resource-limited settings exist.

CONCLUSION

Improved data collection and surveillance of NCDs among PLHIV in LMICs are necessary to inform integrated HIV/NCD care models. Although efforts to integrate care exist, further research is needed to optimize the efficacy of these programs.

Theory of signs and statistical approach to big data in assessing the relevance of clinical biomarkers of inflammation and oxidative stress

Biomarkers are widely used not only as prognostic or diagnostic indicators, or as surrogate markers of disease in clinical trials, but also to formulate theories of pathogenesis. We identify two problems in the use of biomarkers in mechanistic studies. The first problem arises in the case of multifactorial diseases, where different combinations of multiple causes result in patient heterogeneity. The second problem arises when a pathogenic mediator is difficult to measure. This is the case of the oxidative stress (OS) theory of disease, where the causal components are reactive oxygen species (ROS) that have very short half-lives. In this case, it is usual to measure the traces left by the reaction of ROS with biological molecules, rather than the ROS themselves. Borrowing from the philosophical theories of signs, we look at the different facets of biomarkers and discuss their different value and meaning in multifactorial diseases and system medicine to inform their use in patient stratification in personalized medicine.

Non-Communicable Disease Preventive Screening by HIV Care Model

Importance

The Human Immunodeficiency Virus (HIV) epidemic has evolved, with an increasing non-communicable disease (NCD) burden emerging and need for long-term management, yet there are limited data to help delineate the optimal care model to screen for NCDs for this patient population.

Objective

The primary aim was to compare rates of NCD preventive screening in persons living with HIV/AIDS (PLWHA) by type of HIV care model, focusing on metabolic/cardiovascular disease (CVD) and cancer screening. We hypothesized that primary care models that included generalists would have higher preventive screening rates.

Design

Prospective observational cohort study.

Setting

Partners HealthCare System (PHS) encompassing Brigham & Women’s Hospital, Massachusetts General Hospital, and affiliated community health centers.

Participants

PLWHA age >18 engaged in active primary care at PHS.

Exposure

HIV care model categorized as infectious disease (ID) providers only, generalist providers only, or ID plus generalist providers.

Main Outcome(s) and Measures(s)

Odds of screening for metabolic/CVD outcomes including hypertension (HTN), obesity, hyperlipidemia (HL), and diabetes (DM) and cancer including colorectal cancer (CRC), cervical cancer, and breast cancer.

Results

In a cohort of 1565 PLWHA, distribution by HIV care model was 875 ID (56%), 90 generalists (6%), and 600 ID plus generalists (38%). Patients in the generalist group had lower odds of viral suppression but similar CD4 counts and ART exposure as compared with ID and ID plus generalist groups. In analyses adjusting for sociodemographic and clinical covariates and clustering within provider, there were no significant differences in metabolic/CVD or cancer screening rates among the three HIV care models.

Conclusions

There were no notable differences in metabolic/CVD or cancer screening rates by HIV care model after adjusting for sociodemographic and clinical factors. These findings suggest that HIV patients receive similar preventive health care for NCDs independent of HIV care model.

Oral Glucose Tolerance Testing identifies HIV+ infected women with Diabetes Mellitus (DM) not captured by standard DM definition

OBJECTIVE

HIV-infected (HIV+) individuals may have differential risk of diabetes mellitus (DM) compared to the general population, and the optimal diagnostic algorithm for DM in HIV+ persons remains unclear. We aimed to assess the utility of oral glucose tolerance testing (OGTT) for DM diagnosis in a cohort of women with or at risk for HIV infection.

METHODS

Using American Diabetic Association DM definitions, DM prevalence and incidence were assessed among women enrolled in the Women's Interagency HIV Study. DM was defined by 2-hour OGTT ≥ 200 mg/dL (DM_OGTT) or a clinical definition (DM_C) that included any of the following: (i) anti-diabetic medication use or self-reported DM confirmed by either fasting glucose (FG) ≥126 mg/dL or HbA1c ≥ 6.5%, (ii) FG ≥ 126 mg/dL confirmed by a second FG ≥ 126 mg/dL or HbA1c 6.5%, or (iii) HbA1c 6.5% confirmed by FG ≥ 126 mg/dL cohort.

RESULTS

Overall, 390 women (285 HIV+, median age 43 years; 105 HIV-, median age 37 years) were enrolled between 2003-2006. Over half of all women were African American. Using DM_C, DM prevalence rates were 5.6% and 2.8% among HIV+ and HIV- women, respectively. Among HIV+ women, adding DM_OGTT to DM_C increased DM prevalence from 5.6% to 7.4%, a 31% increase in the number of diabetes cases diagnosed (p=0.02). In HIV- women, no additional cases were diagnosed by DM-OGTT.

CONCLUSION

In HIV+ women, OGTT identified DM cases that were not identified by a standardized clinical definition. Further investigation is needed to determine whether OGTT should be considered as an adjunctive tool for DM diagnosis in the setting of HIV infection.

Fructosamine and Hemoglobin A1c Correlations in HIV-Infected Adults in Routine Clinical Care: Impact of Anemia and Albumin Levels

Fructosamine is an alternative method to hemoglobin A1c (HbA1c) for determining average glycemia. However, its use has not been extensively evaluated in persons living with HIV (PLWH). We examined the relationship between HbA1c and fructosamine values, specifically focusing on anemia (which can affect HbA1c) and albumin as a marker of liver disease. We included 345 PLWH from two sites. We examined Spearman rank correlations between fructosamine and HbA1c and performed linear test for trends to compare fructosamine and HbA1c correlations by hemoglobin and albumin quartiles. We examined discrepant individuals with values elevated only on one test. We found a correlation of 0.70 between fructosamine and HbA1c levels. Trend tests for correlations between fructosamine and HbA1c were significant for both albumin (p = 0.05) and hemoglobin (p = 0.01) with the lowest correlations in the lowest hemoglobin quartile. We identified participants with unremarkable HbA1c values but elevated fructosamine values. These discrepant individuals had lower mean hemoglobin levels than those elevated by both tests. We demonstrated a large correlation between HbA1c and fructosamine across a range of hemoglobin and albumin levels. There were discrepant cases particularly among those with lower hemoglobin levels. Future studies are needed to clarify the use of fructosamine for diabetes management in PWLH.

Alternative biomarkers for assessing glycemic control in diabetes: fructosamine, glycated albumin, and 1,5-anhydroglucitol

The growing attention to alternative glycemic biomarkers including fructosamine, glycated albumin (GA), 1,5-anhydroglucitol (1,5-AG), is attributable to the limitations of the glycated hemoglobin (HbA1c) assay. It is important to recognize the conditions in which HbA1c levels may be difficult to interpret. Serum fructosamine and GA have been proposed useful tools for monitoring of short-term glycemic control. These biomarkers not only reflect well glycemic control in hematologic disorder, but also represent postprandial glucose fluctuation. Serum 1,5-AG may be useful for estimating within-day glucose variation. Use of these nontraditional tests can be more helpful in the management of diabetes as complement traditional measures. Further larger cohort studies are warranted to determine whether nontraditional biomarkers have potential utility for early diagnosis, management of diabetes, and prevention of diabetic complications.

Monitoring HIV-infected Patients with Diabetes: Hemoglobin A1c, Fructosamine, or Glucose?

BACKGROUND

Published studies report inappropriately low hemoglobin A1C (HbA1c) values that underestimate glycemia in HIV patients.

METHODS

We reviewed the charts of all HIV patients with diabetes mellitus (DM) at our clinic. Fifty-nine patients had HbA1c data, of whom 26 patients also had fructosamine data. We compared the most recent HbA1c to finger-stick (FS) glucose averaged over three months, and fructosamine to FS averaged over six weeks. Predicted average glucose (pAG) was calculated as reported by Nathan et al: pAG (mg/dL) = 28.7 × A1C% − 46.7. Data were analyzed using the Statistical Analysis System (SAS) and Kruskal–Wallis test.

RESULTS

HbA1c values underestimated (UE) actual average glucose (aAG) in 19% of these patients and overestimated (OE) aAG in 27%. HbA1c estimated aAG within the established range in only 54% of the patients. There were no statistical differences in the types of HIV medication used in patients with UE, OE, or accurately estimated (AE) glycemia. A Spearman correlation coefficient between HbA1c and aAG was r = 0.53 (P < 0.0001). Correlation between fructosamine and aAG was r = 0.47 (P = 0.016).

CONCLUSIONS

The correlations between HbA1c and aAG and between fructosamine and aAG were weaker than expected, and fructosamine was not more accurate than HbA1c.

Diagnosing and managing diabetes in HIV-infected patients: current concepts

Diabetes mellitus (DM) is a common condition with significant associated morbidity and mortality. DM diagnosis and management among human immunodeficiency virus (HIV)-infected patients is a particularly relevant topic as the HIV-infected population ages and more HIV-infected individuals live with chronic medical comorbidities. Although there is mixed evidence regarding HIV as an independent risk factor for DM, multiple factors related to HIV and its treatment are associated with DM. This review covers the epidemiology of DM in HIV-infected patients, and diagnosis, management, and treatment goals for DM in HIV-infected patients. We highlight the most recent DM treatment guidelines from the American Diabetes Association and the European Association for the Study of Diabetes, emphasizing individualization of DM medication therapy and treatment goals. Finally, we review a comprehensive approach to cardiovascular disease risk reduction in HIV-infected patients with DM and measures to prevent other complications of DM.

Inaccuracy of haemoglobin A1c among HIV-infected men: effects of CD4 cell count, antiretroviral therapies and haematological parameters

BACKGROUND

There is limited evidence that among HIV-infected patients haemoglobin A1c (HbA1c) values may not accurately reflect glycaemia. We assessed HbA1c discordance (observed HbA1c - expected HbA1c) and associated factors among HIV-infected participants in the Multicenter AIDS Cohort Study (MACS).

METHODS

Fasting glucose (FG) and HbA1c were measured at each semi-annual MACS visit since 1999. All HIV-infected and HIV-uninfected men for whom at least one FG and HbA1c pair measurement was available were evaluated. Univariate median regression determined the association between HbA1c and FG by HIV serostatus. The relationship between HbA1c and FG in HIV-uninfected men was used to determine the expected HbA1c. Generalized estimating equations determined factors associated with the Hb1Ac discordance among HIV-infected men. Clinically significant discordance was defined as observed HbA1c - expected HbA1c ≤-0.5%.

RESULTS

Over 13 years, 1500 HIV-uninfected and 1357 HIV-infected men were included, with a median of 11 visits for each participant. At an FG of 125 mg/dL, the median HbA1c among HIV-infected men was 0.21% lower than among HIV-uninfected men and the magnitude of this effect increased with FG >126 mg/dL. Sixty-three percent of HIV-infected men had at least one visit with clinically significant HbA1c discordance, which was independently associated with: low CD4 cell count (<500 cells/mm(3)); a regimen containing a protease inhibitor, a non-nucleoside reverse transcriptase inhibitor or zidovudine; high mean corpuscular volume; and abnormal corpuscular haemoglobin.

CONCLUSION

HbA1c underestimates glycaemia in HIV-infected patients and its use in patients with risk factors for HbA1c discordance may lead to under-diagnosis and to under-treatment of established diabetes mellitus.

Clinical features, diagnostic criteria and pathogenesis of diabetes mellitus

Diabetes mellitus is a metabolic disorder of glucose homeostasis and associated with long-term vascular complications leading to morbidity and mortality. It is the fastest growing non-communicable disease throughout the world. The pathophysiology of diabetes is complex and multifactorial. Understanding pathological mechanisms of disease can help clinicians to identify and treat the factors involved effectively, and design preventive strategies so as to halt the pandemic of this deadly disorder.

Association of HIV infection with incident diabetes mellitus: impact of using hemoglobin A1C as a criterion for diabetes

BACKGROUND

Data regarding the association between HIV and diabetes mellitus (DM) are conflicting, with little known regarding the impact of including hemoglobin A1C (A1C) as a criterion for DM.

METHODS

Pooled logistic regression was used to quantify the association between HIV and DM in 1501 HIV-infected and 550 HIV-uninfected participants from the Women's Interagency HIV Study. Incident DM was defined using the following 3 criteria, definition I: fasting glucose (FG) ≥126 mg/dL, anti-DM medication or reporting DM diagnosis (with confirmation by FG ≥126 mg/dL or anti-DM medication); definition II: confirmation with a second FG ≥126 mg/dL, and definition III: addition of A1C ≥6.5% confirmed by FG ≥126 mg/dL or anti-DM medication.

RESULTS

DM incidence per 100 person-years was 2.44, 1.55, and 1.70 for HIV-infected women; 1.89, 0.85, and 1.13 for HIV-uninfected women, using definition I, II, and III, respectively. After adjustment for traditional DM risk factors, HIV infection was associated with 1.23-, 1.90-, and 1.38-fold higher risk of incident DM, respectively; the association reached statistical significance only when confirmation with a second FG ≥126 mg/dL was required. Older age, obesity, and a family history of DM were each consistently and strongly associated with increased DM risk.

CONCLUSIONS

HIV infection is consistently associated with greater risk of DM. Inclusion of an elevated A1C to define DM increases the accuracy of the diagnosis and only slightly attenuates the magnitude of the association otherwise observed between HIV and DM. By contrast, a DM diagnosis made without any confirmatory criteria for FG ≥126 mg/dL overestimates the incidence, while also underestimating the effects of HIV on DM risk, and should be avoided.

HIV infection and glycemic response to newly initiated diabetic medical therapy

OBJECTIVES

Type 2 diabetes (DM2) is increasingly common in HIV-infected individuals. Antiretroviral agents and chronic inflammation may adversely affect glycemic control. However, little is known about the effectiveness of diabetic medical therapy in HIV-infected patients. The objective of this study was to compare the effectiveness of initial diabetic medical therapy in patients with and without HIV infection.

DESIGN

A retrospective cohort study was conducted among adults with DM2 initiating diabetic medications within the Centers for AIDS Research Network of Integrated Clinical Systems cohort.

METHODS

Generalized estimating equations were used to compare changes in hemoglobin A1c (HbA1c) through the year after initiation of therapy, controlling for baseline HbA1c and demographic and clinical covariates.

RESULTS

Two hundred and eighty-six HIV-infected patients and 858 age and sex-matched HIV-uninfected patients initiated diabetic medications during the study period. Overall, patients had an adjusted absolute mean reduction in HbA1c of 1.04% [95% confidence interval (CI) -0.87 to -1.22] during the first year of therapy. HIV-infected patients achieved significantly smaller reductions in HbA1c, with an absolute mean difference of -0.17% (95% CI -0.28 to -0.06; P = 0.003). On subanalyses, HIV-infected patients on a protease inhibitor-based regimen had significantly smaller reductions in HbA1c compared to HIV-uninfected patients (adjusted absolute difference -0.21%, 95% CI -0.35 to -0.08; P = 0.002).

CONCLUSION

Patients with HIV infection who initiate diabetic medical therapy achieve smaller reductions in HbA1c than patients without HIV infection in the course of routine clinical care. This less robust response may in part be related to use of antiretrovirals that exacerbate insulin resistance, specifically protease inhibitors.

Hyperparathyroidism and complications associated with vitamin D deficiency in HIV-infected adults in New York City, New York

Although recent studies report a high prevalence of vitamin D deficiency in HIV-infected adults similar to that in the general population, metabolic complications of vitamin D deficiency may be worsened with HIV infection and remain insufficiently characterized. We conducted a retrospective cross-sectional cohort study to determine prevalence and correlates of vitamin D deficiency and hyperparathyroidism among HIV-infected patients attending an urban clinic. Vitamin D deficiency was defined as 25(OH)-vitamin D <20 ng/ml and insufficiency as 20 to <30 ng/ml, and hyperparathyroidism as parathyroid-hormone >65 pg/ml. We used the X(2) test to compare proportions and logistic regression to assess for associations. Among 463 HIV-infected patients, the prevalence of vitamin D deficiency was 59%. The prevalence of hyperparathyroidism was 30% among patients with vitamin D deficiency, 23% among those with insufficiency, and 12% among those with sufficient vitamin D levels. Vitamin D deficiency was associated with increased odds of hyperparathyroidism. Severe vitamin D deficiency was associated with elevated alkaline phosphatase, a marker for increased bone turnover. Although efavirenz use was associated with vitamin D deficiency, and protease inhibitor use with decreased odds of vitamin D deficiency, there was no statistical difference in rates of hyperparathyroidism stratified by combination antiretroviral therapy (cART) use. Given the increased risk of osteopenia with HIV infection and cART use, vitamin D supplementation for all HIV-infected patients on cART should be prescribed in accordance with the 2011 Endocrine Society guidelines. In HIV-infected patients with severe vitamin D deficiency or hyperparathyroidism, screening for osteomalacia and osteopenia may be warranted.

Drugs affecting HbA1c levels

Glycated hemoglobin (HbA1c) is an important indicator of glycemic control in diabetes mellitus, based on which important diagnostic and therapeutic decisions are routinely made. However, there are several situations in which the level of HbA1c may not faithfully reflect the glycemic control in a given patient. Important among these is the use of certain non-diabetic medications, which can affect the HbA1c levels in different ways. This review focuses on the non-diabetic medications which can inappropriately raise or lower the HbA1c levels, and the postulated mechanisms for the same.

Glycated Hemoglobin A(1c) as screening for diabetes mellitus in HIV-infected individuals

The American Diabetes Association now recommends hemoglobin A(1c) (HbA(1c)) screening for the diagnosis of diabetes. It has been reported that HbA(1c) levels underestimate glycemic levels in HIV-infected persons. We examined the performance of HbA(1c) as a screening test for diabetes in a group of HIV-infected people without diabetes. We conducted a retrospective cross-sectional cohort study among HIV-infected patients determining the sensitivity and specificity of HbA(1c) as a screening test compared to fasting blood glucose (FBG). The effect of treatment regimen on the relationship between HbA(1c) and FBG was assessed by multiple linear regressions. Twenty-two of the 395 patients included in the study were newly diagnosed with diabetes based on FBG≥126 mg/dL. Using a cutoff of HbA(1c)≥6.5%, HbA(1c) had a sensitivity of 40.9% and specificity of 97.5% for identification of incident diabetes. At an HbA(1c) level of 5.8% the product of sensitivity and specificity was maximized, with values of 88.8% and 77.5% respectively. Higher mean cell volume (MCV) values (p=0.02) and current use of a non-nucleoside reverse transcriptase inhibitors (NNRTIs; p=0.02) significantly increased the slope, while PI use significantly decreased the slope (p<0.001), of the linear regression of HbA(1c) compared to FBG. Tenofovir use did not significantly alter the slope or y-intercept of the line. Among HIV-infected nondiabetic patients, HbA(1c) is insensitive, although highly specific for diagnosing diabetes. Current antiretroviral (ART) use has significant and variable influence on the relationship between HbA(1c) and FBG. The use of HbA(1c) in conjunction with FBG may be the best modality to screen for diabetes.

Falsely decreased HbA1c in a type 2 diabetic patient treated with dapsone

Glycated hemoglobin A1c (HbA1c) is an important indicator of glycemic control. The current recommendation for glycemic control based on HbA1c values has been widely accepted. However, HbA1c values depend on the lifespan of erythrocytes and the assay methods used. Here, we report the case of a patient with type 2 diabetes with unusual falling of HbA1c due to interference from dapsone treatment for leukocytoclastic vasculitis. He was a 52-year-old man, who was diagnosed with type 2 diabetes mellitus 5 years previously and who had been treated in our hospital in the past 3 years. Glycemia was controlled by sulfonylurea and metformin. During the 3-years follow-up period, HbA1c dropped significantly during the addition of dapsone treatment, although plasma glucose levels remained stable. HbA1c levels were raised after discontinuation of dapsone. With rechallenge of dapsone usage, HbA1c decreased again. We conclude that dapsone may be the cause of artificially low HbA1c. Other measurements to monitor glycemic control should be considered when dapsone is used for the treatment of concurrent disorders, such as autoimmune disease and pneumocystis jiroveci pneumonia.

South Asian Consensus Guidelines for the rational management of diabetes in human immunodeficiency virus/acquired immunodeficiency syndrome

As newer methods of management are made available, and accessible, survival rates with human immunodeficiency virus (HIV) are increasing. This means that chronic, metabolic complications of HIV are becoming more frequent in clinical practice, as acute morbidity is controlled. Management of HIV/acquired immunodeficiency syndrome (AIDS) is gradually expanding to include these chronic and metabolic complications of the disease, and the adverse effects associated with its treatments, including diabetes. Unfortunately, no guidelines are available to help the medical practitioners choose appropriate therapy for patients with these conditions. The aim of the South Asian Consensus Guidelines is to provide evidence-based recommendations to assist healthcare providers in the rational management of type 2 diabetes mellitus in patients with HIV. The development of these guidelines used systematic reviews of available evidence to form its key recommendations. These guidelines and associated review of literature represent a compilation of available knowledge regarding rational management of diabetes in HIV. Patients of diabetes with concomitant HIV infection are managed optimally with insulin therapy and judicious use of highly active antiretroviral therapy with suitable alternatives is also recommended. These guidelines should prove helpful to physicians, not only in South Asia, but also across the globe, while managing patients with coexistent HIV and diabetes.

Glycated haemoglobin in diabetic women with and without HIV infection: data from the Women's Interagency HIV Study

BACKGROUND

Limited data suggest that glycated haemoglobin (haemoglobin A1c; A1C) values might not reflect glycaemic control accurately in HIV-infected individuals with diabetes.

METHODS

We evaluated repeated measures of paired fasting glucose and A1C values in 315 HIV-infected and 109 HIV-uninfected diabetic participants in the Women's Interagency HIV Study. Generalized estimating equations used log A1C as the outcome variable, with adjustment for log fasting glucose concentration in all models.

RESULTS

An HIV-infected woman on average had 0.9868 times as much A1C (that is, 1.32% lower; 95% confidence interval 0.9734-0.9904) as an HIV-uninfected woman with the same log fasting glucose concentration. In multivariate analyses, HIV serostatus was not associated, but White, other non-Black race, and higher red blood cell mean corpuscular volume (MCV) were statistically associated with lower A1C values. Use of diabetic medication was associated with higher A1C values. In multivariate analyses restricted to HIV-infected women, White and other race, higher MCV, and HCV viraemia were associated with lower A1C values, whereas older age, use of diabetic medications and higher CD4(+) T-cell count were associated with higher A1C values. Use of combination antiretroviral therapy, protease inhibitors, zidovudine, stavudine or abacavir was not associated with A1C values.

CONCLUSIONS

A1C values were modestly lower in HIV-infected diabetic women relative to HIV-uninfected diabetic women after adjustment for fasting glucose concentration. The difference was abrogated by adjustment for MCV, race and diabetic medication use. Our data suggest that in clinical practice A1C gives a reasonably accurate refection of glycaemic control in HIV-infected diabetic women.

Management of the Metabolic Syndrome in Patients With Human Immunodeficiency Virus

Patients with human immunodeficiency virus (HIV) are an increasing subpopulation of patients seen in endocrine/ diabetes clinics. This article explores evidence-based treatment recommendations for patients with metabolic syndrome who are also positive for HIV. Patients infected with HIV may manifest metabolic abnormalities. They often present with low high-density lipoprotein (HDL-C), hypertension, visceral adiposity, and insulin resistance, among other symptoms consistent with features of the metabolic syndrome. The etiologies of the metabolic abnormalities are not completely understood. The role of highly active antiretroviral therapy (HAART) and the separate effect of HIV on patients who are surviving longer may contribute to the increased incidence of the development of the metabolic syndrome. The role of the health care team is to provide patient education to patients with HIV concerning lifestyle modification in order to prevent complications related to the metabolic syndrome.

The effects of intermittent, CD4-guided antiretroviral therapy on body composition and metabolic parameters

OBJECTIVE

To assess the effects of decreased antiretroviral therapy exposure on body fat and metabolic parameters.

DESIGN

Substudy of the Strategies for Management of Anti-Retroviral Therapy study, in which participants were randomized to intermittent CD4-guided [Drug Conservation (DC) group] or to continuous [Viral Suppression (VS) group] antiretroviral therapy.

METHODS

Participants at 33 sites were coenrolled in the Strategies for Management of Anti-Retroviral Therapy Body Composition substudy. Regional fat was assessed annually by whole-body dual-energy X-ray absorptiometry and abdominal computed tomography. Fasting metabolic parameters were assessed at months 4, 8, and annually. Treatment groups were compared for changes in fat and metabolic markers using longitudinal mixed models.

RESULTS

Two hundred and seventy-five patients were randomized to the DC (n = 142) or VS (n = 133) group and followed for a median of 2.0 years. By month 12, limb fat (DC-VS difference 9.8%, 95% confidence interval 3.5-16.1; P = 0.003) and subcutaneous abdominal fat (DC-VS difference 14.3 cm, 95% confidence interval -0.1 to 28.7; P = 0.05) increased in the DC group. There was no treatment difference in visceral abdominal fat (DC-VS difference -2.1%, 95% confidence interval -13.5 to 9.4; P = 0.72). Lipids significantly decreased in the DC group by month 4 and treatment differences persisted throughout follow-up (P < or = 0.001). By 12 months, hemoglobin A1C increased in the DC (+0.3%) and remained stable in the VS group (P = 0.003); the treatment difference remained significant throughout follow-up (P = 0.02).

CONCLUSION

After 12 months, intermittent antiretroviral therapy increased subcutaneous fat, had no effect on visceral abdominal fat, decreased plasma lipids, and increased hemoglobin A1C compared with continuous antiretroviral therapy.

A1C underestimates glycemia in HIV infection

OBJECTIVE

The objective of this study was to determine the relationship between A1C and glycemia in HIV infection.

RESEARCH DESIGN AND METHODS

We completed a prospective cross-sectional study of 100 HIV-infected adults with type 2 diabetes (77%) or fasting hyperglycemia (23%) with measured glucose, A1C, mean corpuscular volume (MCV), and fructosamine. A total of 200 HIV-uninfected type 2 diabetic subjects matched for key demographic characteristics served as control subjects.

RESULTS

Relative to the control subjects, A1C underestimated glucose by 29 +/- 4 mg/dl in the HIV-infected subjects. Current nucleoside reverse transcriptase inhibitors (NRTIs), higher MCV and hemoglobin, and lower HIV RNA and haptoglobin were associated with greater A1C-glucose discordance. However, only MCV and current NTRI use, in particular abacavir, remained significant predictors in multivariate analyses. Fructosamine more closely reflected glycemia in the HIV-infected subjects.

CONCLUSIONS

A1C underestimates glycemia in HIV-infected patients and is related to NRTI use. Use of abacavir and increased MCV were key correlates in multivariate analyses. Fructosamine may be more appropriate in this setting.

No relationship between mean plasma glucose and glycated haemoglobin in patients with cystic fibrosis-related diabetes

AIM

Cystic fibrosis-related diabetes (CFRD) prevalence has increased dramatically with the improved life expectancy of patients with cystic fibrosis (CF). Glycated haemoglobin (HbA(1c)) is an important tool for monitoring blood glucose control but, unlike in type 1 and type 2 diabetes, a correlation between HbA(1c), fructosamine and mean plasma glucose has not been clearly established in CF. This study aimed to examine the relationship between mean plasma glucose and HbA(1c) or fructosamine in stable patients with CFRD.

METHODS

Fifteen type 1 diabetes and 13 CFRD patients (HbA(1c)<9.0%; no anaemia), matched for age and body mass index (BMI), provided 72 capillary blood glucose profiles taken 3days/month for three months. At the end of this time, HbA(1c) and fructosamine were measured. Mean plasma glucose was estimated using the Diabetes Control and Complications Trial (DCCT) conversion formula, and linear regressions carried out to establish its relationship with HbA(1c) and fructosamine.

RESULTS

In type 1 diabetes patients, mean plasma glucose correlated significantly with HbA(1c) (r=0.68; P=0.005). In CFRD patients, no correlation was found between mean plasma glucose and HbA(1c) (r=0.24; P=0.460). Also, no association was found between mean plasma glucose, representing the month before blood sampling, and fructosamine in either group.

CONCLUSION

Unlike in type 1 diabetes, HbA(1c) did not correlate with mean plasma glucose in CFRD subjects. Thus, having a normal HbA(1c) may not be sufficient to indicate a low risk of diabetes complications in CFRD. Further studies are required to explain such a discrepancy.

Assessing glycemic control with self-monitoring of blood glucose and hemoglobin A(1c) measurements

Hemoglobin A(1c) (HbA(1c)) is the gold standard for monitoring glycemic control and serves as a surrogate for diabetes-related complications. Although HbA(1c) measures mean glycemic exposure during the preceding 2 to 3 months, it does not provide iInformation about day-to-day changes in glucose levels. Self-monitoring of blood glucose represents an important adjunct to HbA(1c) because it can distinguish among fasting, preprandial, and postprandial hyperglycemia; detect glycemic excursions; identify hypoglycemia; and provide immediate feedback to patients about the effect of food choices, activity, and medication on glycemic control.

Inappropriately low glycated hemoglobin values and hemolysis in HIV-infected patients

In order to test the accuracy of glycated hemoglobin (HbA1c) in predicting mean glycemia in HIV-infected patients, we recorded consecutive HbA1c measurements from 1238 non-HIV-infected and 112 HIV-infected patients, all devoid of any hemoglobinopathy, in a retrospective, transversal study. Mean fasting glycemia from the six previous weeks (measured-Gly) and HbA1c-estimated glycemia [HbA1c-Gly (1.85x%HbA1c-4.78) mM] were compared. Mean hemoglobin, red cell volume, serum creatinine, CD4 count, and HIV viral load from the same period were collected in HIV-infected patients. Although measured-Gly was not significantly different between non-HIV-infected (6.95+/-3.23 mM) and HIV-infected patients (6.62+/-2.42 mM), HbA1c underestimated the mean fasting glycemia by 12.3% in HIV-infected as compared to non-HIV-infected patients (p=0.0001). The difference "measured-Gly-HbA1c-Gly" was correlated with the red cell volume (p<0.0001) in HIV-infected patients. We then searched for the presence of subclinical hemolysis, a cause of both macrocytosis and reduced HbA1c levels, in HIV-infected patients. To this end, we prospectively measured serum haptoglobin in 249 consecutive samples from HIV-infected subjects without any known cause of hemolysis. A very low haptoglobin level, a marker of hemolysis, was frequent and negatively correlated with the red cell volume in these patients. Treatment with nucleoside analogues was significantly associated with macrocytosis and low haptoglobin. In conclusion, HbA1c could be inappropriately low in HIV-infected patients. Its underestimation of mean fasting glycemia could be due to an antiretroviral-induced subclinical hemolysis, but further studies are needed to explore this hypothesis. Self-monitoring of blood glucose and search for latent hemolysis should be promoted in diabetic HIV-infected patients.

Decline in haemoglobin A1c values in diabetic patients receiving interferon-alpha and ribavirin for chronic hepatitis C

Haemoglobin A1c (A1c) levels are lower during haemolysis because of the shorter exposure of haemoglobin (Hb) to plasma glucose. Ribavirin (RBV) used in combination with interferon-alpha (IFN) for chronic hepatitis C causes reversible haemolytic anaemia. This study examined the extent to which RBV treatment influences A1c levels in diabetic patients. A retrospective analysis identified 32 diabetic patients who underwent hepatitis C treatment with IFN and RBV. Each subject had at least three measures of A1c, Hb and glucose: before, during and after therapy. A1c values decreased from a mean pretreatment level of 7.2% to an on-treatment A1c level of 5.2% [mean paired difference -2.01%; 95% confidence interval (CI) -1.59% to -2.43%; P < 0.001]. During therapy, mean Hb levels decreased from 15.1 g/dL at baseline to a nadir of 11.7 g/dL (P < 0.001) with a rise in lactose dehydrogenase levels and reticulocyte counts, and unchanged mean corpuscular volume values confirming haemolysis. At the same time, glucose levels declined by a mean of 38.4 mg/dL (95% CI 13.4-63.5 mg/dL; P = 0.002) as did body weights by a mean of 3.15 kg (P < 0.001). According to published glucose-A1c correlation tables, this decline of glucose concentration by 38.4 mg/dL correlates to a decline in A1c level of 1.08%. In conclusion, reductions of A1c levels by a mean of 2.01% during hepatitis C therapy with IFN + RBV are due to a combination of decreased glucose levels (1.08%) and RBV-induced haemolysis (0.93%). A1c levels should not be measured during hepatitis C treatment with IFN + RBV because they do not adequately reflect glycaemic control.