Glycated haemoglobin threshold for dysglycaemia screening, and application to metabolic syndrome diagnosis in HIV-infected Africans

Feasibility of prevention of type 2 diabetes in low- and middle-income countries

Type 2 diabetes is a leading cause of global mortality and morbidity. Nearly 80% of individuals with diabetes live in low- and middle-income countries (LMICs), where nearly half of those with the condition remain undiagnosed. The majority of known cases have sub-optimal clinical outcomes. Moreover, large populations with impaired glucose tolerance and/or impaired fasting glucose contribute to the rapid increase in type 2 diabetes. Globally, priority should be given to limit the population with diabetes, especially in LMICs, alongside actions to optimise the care of people diagnosed with diabetes. Primary prevention studies in LMICs have generated evidence to show the efficacy and scalability of strategies to fully prevent or delay the development of diabetes in high-risk groups. However, these are mainly limited to certain countries in Asia, particularly China and India. The studies have indicated that prevention policies are effective in populations with a high risk of type 2 diabetes, and they also have long-term benefits, not only for the risk of type 2 diabetes but also for the risk of associated metabolic disorders, such as CVDs. For the effective conduct of national programmes, innovative mechanisms must be implemented, such as the use of information technology, joint efforts of multiple teams implementing similar programmes, and involvement of governmental and non-governmental partnerships. Continuous monitoring and long-term studies are required to assess the utility of these programmes. The effectiveness of such programmes in LMICs has not been proven over the longer term, except in China. Despite the available evidence, the feasibility of prevention strategies for type 2 diabetes in LMICs at population level remains an enigma. There remain challenges in the form of cultural, societal and economic constraints; insufficient infrastructure and healthcare capacity; and the non-fully elucidated natural history and determinants of type 2 diabetes in LMICs.

Associations of HIV and prevalent type 2 diabetes mellitus in the context of obesity in South Africa

It is unclear how rising obesity among people with HIV (PWH) in sub-Saharan Africa (SSA) impacts their risk of type 2 diabetes mellitus (diabetes). Using a South African national cross-sectional sample of adult PWH and their peers without HIV (PWOH), we examined the associations between HIV and prevalent diabetes across the spectrum of body mass index (BMI), waist circumference (WC) and waist-to-height ratio (WtHR). Analyses were sex stratified, and adjusted for age, sociodemographic and behavioral factors. The prevalence of diabetes among males was similar between PWH and PWOH, overall and at all levels of adiposity. In contrast, overall diabetes prevalence was higher among female PWOH than female PWH. However, there were differences according to adiposity such that, compared to female PWOH, relative diabetes prevalence in female PWH was reduced with obesity but accentuated with leanness. These differences in the relationship between adiposity and diabetes by HIV serostatus call for better mechanistic understanding of sex-specific adipose tissue biology in HIV in South Africa, and possibly in other HIV endemic settings in SSA.

Optimal glycated hemoglobin A1c value for prediabetes and diabetes in patients with pancreatic diseases

Background

Some articles suggest that using HbA1c alone for diabetes diagnosis is inappropriate. It requires considerable researches to explore the efficacy of HbA1c for diagnosing hyperglycemia in patients with pancreatic disease.

Methods

This study analyzed 732 patients, comprising of 331 without pancreatic disease and 401 patients diagnosed with pancreatic diseases. All participants underwent the HbA1c assay and oral glucose tolerance test. Kappa coefficients were calculated to assess agreement between the HbA1c and glucose criteria. The receiver operating characteristic curve (ROC) was used to calculate the optimal HbA1c value. DeLong test was analyzed to compared the aera under curves (AUCs).

Results

There were 203 (61.3%) patients with NGT, 78 (23.6%) with prediabetes, and 50 (15.1%) with diabetes in patients without pancreatic diseases. In patients with pancreatic disease, 106 participants were diagnosed with NGT (36.4%), 125 with prediabetes (31.2%), and 130 with diabetes (32.4%). Patients with pancreatic disease exhibited elevated levels of bilirubin, transaminase enzymes, aspartate transaminase, high density lipoprotein cholesterol and total bile acid. The sensitivity and specificity of the HbA1c (6.5%) for diagnosing pancreatic diabetes were 60.8% (95% CI 52.3, 69.3) and 92.6% (95% CI 89.5, 95.7). In prediabetes, the sensitivity and specificity of HbA1c (5.7%) is 53.2% (44.3, 62.0) and 59.6 (51.5, 67.6). The optimal HbA1c value for diagnosing diabetes was 6.0% (AUC = 0.876, 95% CI 0.839, 0.906), with the sensitivity of 83.8% and the specificity of 76.8%. The optimal HbA1c value for the diagnosis of prediabetes was 5.8% (AUC = 0.617, 95% CI: 0.556, 0.675), with the corresponding sensitivity and specificity of 48.0% and 72.6% respectively. The combined tests (HbA1c, 6.0% or FPG, 7.0mmol/L) presented the sensitivity of 85.7% (95% CI 79.1, 91.3)and the specificity of 92.6% (95% CI 87.6, 97.3) in pancreatic diabetes.

Conclusion

From our results, the recommended HbA1c by ADA criterion may not be sufficiently sensitive to diagnose hyperglycemia in pancreatic disease. The optimal value of 5.8% and 6.0% improved the accuracy for diagnosing prediabetes and diabetes and should be considered to be applied. Besides, we advocate the combination of HbA1c and FPG test for the diagnosis of diabetes in patients with pancreatic diseases.

Prevalence and influences of diabetes and prediabetes among adults living with HIV in Africa: a systematic review and meta-analysis

INTRODUCTION

In people living with human immunodeficiency virus (PLHIV), traditional cardiovascular risk factors, exposure to HIV per se and antiretroviral therapy (ART) are assumed to contribute to cardiometabolic diseases. Nevertheless, controversy exists on the relationship of HIV and ART with diabetes. To clarify the relationship between HIV and type 2 diabetes, this review determined, in PLHIV in Africa, diabetes and prediabetes prevalence, and the extent to which their relationship was modified by socio-demographic characteristics, body mass index (BMI), diagnostic definitions used for diabetes and prediabetes, and HIV-related characteristics, including CD4 count, and use and duration of ART.

METHODS

For this systematic review and meta-analysis (PROSPERO registration CRD42021231547), a comprehensive search of major databases (PubMed-MEDLINE, Scopus, Web of Science, Google Scholar and WHO Global Health Library) was conducted. Original research articles published between 2000 and 2021 in English and French were included, irrespective of study design, data collection techniques and diagnostic definitions used. Observational studies comprising at least 30 PLHIV and reporting on diabetes and/or prediabetes prevalence in Africa were included. Study-specific estimates were pooled using random effects models to generate the overall prevalence for each diagnostic definition. Data analyses used R statistical software and "meta" package.

RESULTS

Of the 2614 records initially screened, 366 full-text articles were assessed for eligibility and 61 were selected. In the systematic review, all studies were cross-sectional by design and clinic-based, except for five population-based studies. Across studies included in the meta-analysis, the proportion of men was 16-84%. Mean/median age was 30-62 years. Among 86,412 and 7976 participants, diabetes and prediabetes prevalence rates were 5.1% (95% CI: 4.3-5.9) and 15.1% (9.7-21.5). Self-reported diabetes (3.5%) was lower than when combined with biochemical assessments (6.2%; 7.2%).

DISCUSSION

While not statistically significant, diabetes and prediabetes were higher with greater BMI, in older participants, urban residents and more recent publications. Diabetes and prediabetes were not significantly different by HIV-related factors, including CD4 count and ART.

CONCLUSIONS

Although HIV-related factors did not modify prevalence, the diabetes burden in African PLHIV was considerable with suboptimal detection, and likely influenced by traditional risk factors. Furthermore, high prediabetes prevalence foreshadows substantial increases in future diabetes in African PLHIV.

Glycated haemoglobin and fasting plasma glucose tests in the screening of outpatients for diabetes and abnormal glucose regulation in Uganda: A diagnostic accuracy study

BACKGROUND AND OBJECTIVES

To understand the utility of glycated haemoglobin (HBA1C) in screening for diabetes and Abnormal Glucose Regulation (AGR) in primary care, we compared its performance to that of the fasting plasma glucose (FPG) test.

METHODS

This was a prospective diagnostic accuracy study conducted in eastern Uganda. Patients eligible for inclusion were consecutive adults, 30-75 years, receiving care at the outpatient department of a general hospital in eastern Uganda. We determined the sensitivity, specificity and optimum cut-off points for HBA1C and FPG tests using the oral glucose tolerance test (OGTT) as a clinical reference standard.

RESULTS

A total of 1659 participants underwent FPG testing of whom 310 were also HBA1C and OGTT tested. A total of 113 tested positive for diabetes and 168 for AGR on the OGTT. At recommended cut-off points for diabetes, the HBA1C and FPG tests had comparable sensitivity [69.8% (95% CI 46.3-86.1) versus 62.6% (95% CI 41.5-79.8), respectively] and specificity [98.6% (95% CI 95.4-99.6) versus 99.4% (95% CI 98.9-99.7), respectively]. Similarly, the sensitivity of HBA1C and the FPG tests for Abnormal Glucose Regulation (AGR) at ADA cut-offs were comparable [58.9% (95% CI 46.7-70.2) vs 47.7% (95% CI 37.3-58.4), respectively]; however, the HBA1C test had lower specificity [70.7% (95% CI 65.1-75.8)] than the FPG test [93.5% (95% CI 88.6-96.4)]. At the optimum cut-offs points for diabetes [45.0 mmol/mol (6.3%) for HBA1C and 6.4 mmol/L (115.2 mg/dl) for FPG], HBA1C and FPG sensitivity [71.2% (95% CI 46.9-87.8) versus 72.7% (95% CI 49.5-87.8), respectively] and specificity [95.1% (95% CI91.8 97.2) versus 98.7% (95% CI 98.0 99.2), respectively] were comparable. Similarly, at the optimum cut-off points for AGR [42.0 mmol/mol (6.0%) for the HBA1C and 5.5 mmol/l (99.0 mg/dl) for the FPG test], HBA1C and FPG sensitivity [42.3% (95% CI 31.8-53.6) and 53.2 (95% CI 43.1-63.1), respectively] and specificity [89.1% (95% CI 84.1 92.7) and 92.7% (95% CI 91.0 94.1), respectively] were comparable.

DISCUSSION

HBA1C is a viable alternative diabetes screening and confirmatory test to the FPG test; however, the utility of both tests in screening for prediabetes in this outpatient population is limited.

HIV infection and anaemia do not affect HbA1c for the detection of diabetes in black South Africans: Evidence from the Durban Diabetes Study

OBJECTIVE

South Africa has a high burden of HIV infection and anaemia. These conditions may cause HbA_1c to over- or underestimate glycaemia; however, this has not been comprehensively investigated in African populations. We assessed the association of anaemia, HIV infection and antiretroviral therapy (ART) with HbA_1c , and implications for the detection and diagnosis of diabetes, in a black South African population.

RESEARCH DESIGN AND METHODS

In this population-based cross-sectional study in eThekwini municipality (Durban), South Africa, we assessed HbA_1c and conducted oral glucose tolerance tests (OGTTs), HIV diagnostic tests and full blood count measurements among 1067 participants without a history of diabetes diagnosis. Linear regression was used to examine differences in HbA_1c by anaemia (comparator: no anaemia), or HIV and ART (comparator: no HIV) status. HbA_1c -based diabetes prevalence was compared with OGTT-based prevalence among individuals with anaemia and with untreated and ART-treated HIV.

RESULTS

In adjusted analyses, normocytic and microcytic anaemia were associated with higher HbA_1c compared with no anaemia, whereas macrocytic anaemia and ART-treated HIV were associated with lower HbA_1c compared with no anaemia and no HIV, respectively. However, magnitudes of association were small (range: β  = -3.4 mmol/mol or -0.31%, p < 0.001 [macrocytic anaemia] to β = 2.1 mmol/mol or 0.19%, p < 0.001 [microcytic anaemia]). There was no significant difference in diabetes prevalence based on HbA_1c or OGTT among individuals with anaemia (2.9% vs. 3.3%, p = 0.69), untreated HIV (1.6% vs. 1.6% p = 1.00) or ART-treated HIV (2.9% vs. 1.2%, p = 0.08).

CONCLUSIONS

Our results suggest that anaemia and HIV status appear unlikely to materially affect the utility of HbA_1c for diabetes detection and diagnosis in this population. Further studies are needed to examine these associations in sub-Saharan African populations.

Recent data on adipose tissue, insulin resistance, diabetes and dyslipidaemia in antiretroviral therapy controlled HIV-infected persons

PURPOSE OF REVIEW

Increased total body fat with truncal redistribution is common in antiretroviral therapy (ART)-controlled persons living with HIV(PLWH), leading to insulin resistance, prediabetes/diabetes and dyslipidaemia. We address these topics here.

RECENT FINDINGS

Most antiretrovirals are associated with gain in trunk fat, including visceral adipose tissue (VAT). Protease-inhibitors could inhibit white fat ability to dissipate energy (i.e. beiging) favouring fat gain. Expansion of VAT is associated with a pro-inflammatory profile linked to the tryptophan-kynurenine pathway and CD4+ subtypes. ART-associated increased adipose tissue (AT) quantity leads to decreased AT density, insulin resistance and dyslipidaemia that could be improved by lifestyle modifications.PLWH present high level of insulin resistance, regardless of their treatment, and a higher prevalence of prediabetes, but not diabetes, than noninfected persons. Otherwise, HbA1c values appear inaccurate to diagnose prediabetes/diabetes in PLWH.ART-related-dyslipidaemia is characterized by elevated LDL-C and/or high triglycerides and reduced HDL-C. Whereas treatment with protease inhibitors generally results in worsened lipid values, treatment with integrase-strand-transfer-inhibitors is associated with a better profile. Tenofovir-alafenamide is associated with higher lipid levels than tenofovir-disoproxil-fumarate. Treatment of LDL-C-dyslipidaemia could benefit, in statin-insufficiently controlled patients, from the class of proprotein-convertase-subtilsin-kenin-type-9 (PCSK-9) inhibitors.

SUMMARY

Lifestyle modifications are mandatory to reduce fat and improve dysglycaemia/dyslipidaemia. New drugs can efficiently control diabetes and LDL-C-dyslipidaemia.

The investigation of diabetes in people living with HIV: A systematic review

AIMS

HbA_1c is reported to underestimate glycaemia in people living with HIV (PLHIV). There is not an internationally agreed screening method for diabetes. The primary aim was to identify which tests are performed to diagnose and monitor diabetes in PLHIV. Secondary aims were to identify whether prevalence or incidence of diabetes differs according to marker of glycaemia and how figures compare in PLHIV compared to people without.

METHODS

Electronic databases were searched for studies investigating diabetes in PLHIV, not pregnant, aged ≥18 years. Narrative analysis and descriptive statistics were used to describe which markers of glycaemia, and their frequency, were employed in the diagnosis and monitoring of diabetes in PLHIV. Diagnostic studies provided prevalence or incidence of diabetes.

RESULTS

In all, 45 of 1028 studies were included. Oral glucose tolerance test (OGTT), fasting glucose (FG), HbA_1c and Fructosamine were used to investigate diabetes. In total, 27 studies described diagnosing diabetes, 14 using OGTT, 12 FG and 7 HbA1c. All 18 studies monitoring diabetes used HbA1c. Prevalence ranged from 1.3% to 26% and incidence 2.9% to 12.8%. Studies using glucose and HbA_1c reported HbA_1c to diagnose fewer people with diabetes, monitoring studies found HbA_1c to underestimate glycaemia levels. Controlled studies demonstrate diabetes was more common in PLHIV.

CONCLUSION

OGTT was used most frequently to diagnose diabetes, and HbA_1c to monitor known diabetes. Prevalence and incidence varied depending on marker of glycaemia used. Studies reported a discrepancy in accuracy of HbA_1c in PLHIV, to address this, well-designed, prospective studies, providing individual-level data on HbA_1c levels and an additional marker of glycaemia in PLHIV are needed.

Management of periodontal disease in patients with diabetes- good clinical practice guidelines: A joint statement by Indian Society of Periodontology and Research Society for the Study of Diabetes in India

There is a huge body of literature suggesting an association and a bidirectional relationship between periodontal disease and diabetes. Diabetes and periodontal diseases are both chronic diseases with a high prevalence. Dentists/periodontists, in their daily clinical practice, very often attend to diabetes patients with diverse oral health conditions and cater to their dental treatment needs. Safe and effective periodontal therapy in this population requires a broad understanding of diabetes, medical management of diabetes, and essential modifications to dental/periodontal therapy that may be required. This paper describes a joint statement put forth by the Indian Society of Periodontology and the Research Society for the Study of Diabetes in India aiming to provide expert consensus and evidence-based guidelines for optimal clinical management of periodontal conditions in diabetes patients or patients at risk for diabetes. Although this paper is not envisioned to be a comprehensive review of this topic, it intends to provide the guidelines for dental professionals and periodontists.