Random blood glucose as a screening test for diabetes in a biethnic population

Appropriate use of plasma glucose tests for diagnosis of diabetes mellitus in Ibadan, Nigeria

Background: Diabetes mellitus is a growing epidemic in Africa. Its diagnosis relies exclusively on laboratory evidence, which differs based on clinical circumstances.Objective: The study described the appropriateness of plasma glucose test requests per the American Diabetes Association criteria.Methods: We reviewed the plasma glucose test requests received by the chemical pathology laboratory of the University College Hospital, Ibadan, Nigeria between June 2018 and November 2018. The American Diabetes Association diabetes diagnostic criteria were used to define the appropriateness of test requests and determine the potential for ill-informed clinical decisions.Results: Four hundred and twenty-three requisition forms were included, with the majority from the medical wards/clinics (72.3%); the most frequent reason for a plasma glucose test was systemic hypertension (28.6%). Fasting plasma glucose was most requested (254; 60.0%). One hundred and sixteen (27.4%) requests were potentially inappropriate, with the 2-h postprandial plasma glucose (2hPPG) test requests (83; 71.6%) being the most inappropriate. The difference in the proportion of inappropriate requests was not statistically significantly between medical or surgical wards/clinics (Odds ratio 1.131, 95% confidence interval 0.709–1.803, p = 0.605). Inappropriate requests in six cases may have triggered inappropriate action.Conclusion: A third of the glucose tests requested for querying diabetes mellitus may have been inappropriate. Results of such testing may trigger inappropriate clinical action. To improve the quality of care and for economic reasons, laboratories should have programmes to improve the appropriate use of their services.

Tuberculosis risk among people with diabetes mellitus in Sub-Saharan Africa: a systematic review

Objectives

People with diabetes mellitus (DM) have a higher tuberculosis (TB) risk, but the evidence from sub‐Saharan Africa (SSA) was scarce until recently and not included in earlier global summaries. Therefore, this systematic review aims to determine the risk of active TB disease among people with DM in SSA and whether HIV alters this association.

Methods

Medline, Embase, CINAHL, Web of Science, Global Health and African Index Medicus were searched between January 1980 and February 2021. Cohort, case‐control and cross‐sectional studies from SSA, which assessed the association between DM and active TB, were included if adjusted for age. Two researchers independently assessed titles, abstracts, full texts, extracted data and assessed the risk of bias. Estimates for the association between DM and TB were summarised using a random effects meta‐analysis. PROSPERO: CRD42021241743.

Results

Nine eligible studies were identified, which reported on 110,905 people from 5 countries. Individual study odds ratios (OR) of the TB–DM association ranged from 0.88 (95% CI 0.17–4.58) to 10.7 (95% CI 4.5–26). The pooled OR was 2.77 (95% CI 1.90–4.05). High heterogeneity was reduced in sensitivity analysis (from I² = 57% to I² = 6.9%), by excluding one study which ascertained DM by HbA1c. Risk of bias varied widely between studies, especially concerning the way in which DM status was determined.

Conclusions

There is a strong positive association between DM and active TB in SSA. More research is needed to determine whether HIV, a key risk factor for TB in SSA, modifies this relationship.

Diabetes screening among active tuberculosis patients in Western Australia Tuberculosis Control Program using HbA1c

BACKGROUND

Diabetes mellitus is an important risk factor for tuberculosis (TB), and studies in high TB burden countries have shown diabetes screening to be both feasible and to have a high yield. However, scarce information is available for low TB burden countries. Diabetes screening was previously not part of our routine practice.

AIM

To screen and determine the prevalence of diabetes in the Western Australian Tuberculosis Control Program.

METHODS

We measured HbA1c and random plasma glucose in patients with active TB. We also collected details on their demographics, TB and diabetes.

RESULTS

A total of 105 patients was recruited over a year. Of those, 17 (16.2%) had diabetes. Seven cases (6.7%) were newly diagnosed diabetics. Age, cavitating disease and family history of diabetes were found to be significantly associated with diabetes. Multilobar disease, gender, body mass index, smear and culture positivity were not significantly different between groups.

CONCLUSION

Our study showed high prevalence of diabetes among active TB patients. Diabetes screening at diagnosis of active TB presents as a good opportunity to detect diabetes even in low prevalence country and has become part of our standard care.

Glucose challenge test screening for prediabetes and early diabetes

AIMS

To test the hypothesis that a 50-g oral glucose challenge test with 1-h glucose measurement would have superior performance compared with other opportunistic screening methods.

METHODS

In this prospective study in a Veterans Health Administration primary care clinic, the following test performances, measured by area under receiver-operating characteristic curves, were compared: 50-g oral glucose challenge test; random glucose; and HbA1c level, using a 75-g oral glucose tolerance test as the 'gold standard'.

RESULTS

The study population was comprised of 1535 people (mean age 56 years, BMI 30.3 kg/m2 , 94% men, 74% black). By oral glucose tolerance test criteria, diabetes was present in 10% and high-risk prediabetes was present in 22% of participants. The plasma glucose challenge test provided area under receiver-operating characteristic curves of 0.85 (95% CI 0.78-0.91) to detect diabetes and 0.76 (95% CI 0.72-0.80) to detect high-risk dysglycaemia (diabetes or high-risk prediabetes), while area under receiver-operating characteristic curves for the capillary glucose challenge test were 0.82 (95% CI 0.75-0.89) and 0.73 (95% CI 0.69-0.77) for diabetes and high-risk dysglycaemia, respectively. Random glucose performed less well [plasma: 0.76 (95% CI 0.69-0.82) and 0.66 (95% CI 0.62-0.71), respectively; capillary: 0.72 (95% CI 0.65-0.80) and 0.64 (95% CI 0.59-0.68), respectively], and HbA1c performed even less well [0.67 (95% CI 0.57-0.76) and 0.63 (95% CI 0.58-0.68), respectively]. The cost of identifying one case of high-risk dysglycaemia with a plasma glucose challenge test would be $42 from a Veterans Health Administration perspective, and $55 from a US Medicare perspective.

CONCLUSIONS

Glucose challenge test screening, followed, if abnormal, by an oral glucose tolerance test, would be convenient and more accurate than other opportunistic tests. Use of glucose challenge test screening could improve management by permitting earlier therapy.

Antioxidant and metabolic impairment result in DNA damage in arsenic-exposed individuals with severe dermatological manifestations in Eastern India

Arsenic is an environmental toxicant, free-radical generator, carcinogenic agent, and aging promoter. Recently, blood samples were analyzed from individuals (control- male 12, female 13; arsenic-exposed- male 16, female 14; and exposed to ≥100 μg/L As, ≥10 y) with dermatological symptoms in few affected villages in Eastern India to unravel their hematopoietic, metabolic, and antioxidant profiles. White blood cells recovered from buffy coat were used for DNA fragmentation test. Present observation suggests that significant number of individuals developed pigmentation and palmoplantar hyperkeratosis with black-brownish patch on their body and many of those developed carcinomas. Hematopoietic data show a significant increase in eosinophil and decrease in monocyte count in either sex. Though insignificant, an increase in neutrophil in female and lymphocyte count in male arsenic-exposed individuals are supported by the earlier report on sex dimorphic immune sensitization. Significant increase in serum alanine transaminase in both sexes and bilirubin only in male suggests the eventuality of hepatic disintegration. Arsenic exposure significantly decreased serum amylase in female. A significant decrease in antioxidant components like catalase, soluble thiol, and recently recognized uric acid worsened the situation by generating free radicals as observed in significant rise in malondialdehyde level, which finally increased DNA fragmentation and arsenic-associated mutagenesis and carcinogenesis. This could attribute to lowering in immune competence and related necrotic and/or apoptotic manifestations.

Random blood glucose measurement at antenatal booking to screen for overt diabetes in pregnancy: a retrospective study

OBJECTIVE

To assess random venous blood glucose (RBG) measurement at antenatal booking to detect "overt diabetes in pregnancy" (ODIP).

RESEARCH DESIGN AND METHODS

A retrospective analysis of regional hospital obstetric data from 2004-2008 was performed. Universal RBG screening was included at booking. Oral glucose tolerance test (OGTT) was administered if RBG >7.0 mmol/L or other indications, e.g., if a 50-g glucose challenge test was >7.7 mmol/L at 26-28 weeks. ODIP was based upon World Health Organization plasma glucose criteria for diabetes.

RESULTS

RBG data were collected from 17,852/26,369 (67.7%) pregnancies around the initial antenatal visit; 3,007 women had an OGTT. The receiver operator curve area under the curve for RBG to detect ODIP was 0.86 (0.80-0.92) (assuming women without an OGTT did not have ODIP).

CONCLUSIONS

RBG at booking may provide a sufficiently sensitive screening tool for the detection of ODIP. We recommend further studies and comparison with fasting glucose and HbA(1c).

Point-of-care testing as a tool for screening for diabetes and pre-diabetes

AIM

To determine the utility of finger-prick point-of-care testing (POCT) of blood glucose for the detection of dysglycaemia.

METHODS

A fasting POCT and an oral glucose tolerance test (OGTT) with laboratory assays were performed as part of the baseline screening for 5309 participants enrolled in the Te Wai o Rona Diabetes Prevention Strategy. Participants were aged 46 +/- 19 years with no self-reported diabetes. Dysglycaemia, including diabetes, was defined using World Health Organization criteria. Agreement between the two fasting plasma glucose measurements and their screening properties (with sensitivity and specificity for cut points) were compared using receiver operator characteristic analysis.

RESULTS

A total of 3225 participants had both capillary and venous fasting blood sampled within 30 min and then underwent OGTT. New diabetes was found in 161 participants (5.0%) and pre-diabetes in 414 [impaired glucose tolerance 299 (9.3%), impaired fasting glucose 115 (3.6%)]. The mean difference in capillary and venous measures was 0.02 mmol/l (95% confidence interval -0.04 to +0.01; limits of agreement -1.37 to 1.33 mmol/l). Capillary POCT was a poorer predictor of dysglycaemia and impaired glucose tolerance and new diabetes (area under curve 0.76 and 0.71) than venous laboratory analysis (area under curve 0.87 and 0.81 respectively). Optimal screening criteria were best at a venous glucose of 5.4 mmol/l; 77% sensitivity/specificity.

CONCLUSIONS

POCT significantly underestimated the true blood glucose at diagnostic levels for diabetes. POCT cannot be recommended as a means of screening for or diagnosing diabetes or pre-diabetes.

Comparability of venous and capillary glucose measurements in blood

AIM

Diabetes and glucose intolerance are diagnosed by measurement of glucose in blood. Glucose is usually measured as venous plasma or capillary whole blood and diagnostic criteria frequently provide equivalence estimates for these two methods. This study examined the relationship between glucose measured in capillary and venous samples collected at random, fasting and 2 h after oral glucose.

METHODS

Simultaneous measurements of venous plasma and capillary blood glucose were performed on random samples in 609 people, fasting samples in 685 people, and 2 h after oral glucose samples in 463 people. Separate capillary and venous samples were collected each time. A variance component model was used to construct conversion algorithms between venous and capillary results.

RESULTS

The relationship between venous and capillary glucose values varied, with venous plasma being higher than capillary blood for random and fasting samples but lower for sampling 2 h after oral glucose. Discrepancies were observed between measured capillary blood values and the published WHO capillary blood equivalence values for venous plasma values for all except a fasting venous value of 7.0 mmol/l. For example, for a fasting venous plasma glucose of 6.1 mmol/l the WHO equivalent value is 5.6 mmol/l, while the measured value was 5.2 mmol/l, and for a 2-h venous plasma glucose of 11.1 mmol/l the WHO value is 11.1 mmol/l, while the measured result was 11.7 mmol/l.

CONCLUSIONS

These results highlight the difficulty in equating glucose levels from one sampling and measuring procedure to another, and raise uncertainties about current published equivalence values which could lead to misclassifications in glucose tolerance status.

The utility of a single glucometer measurement of fasting capillary blood glucose in the prevalence determination of diabetes mellitus in an urban adult Palestinian population

This paper aims to evaluate the utility of a single glucometer fasting capillary blood glucose (FCBG) measurement in determining the prevalence of diabetes mellitus in a homogeneous adult population. FCBG measurements were compared with results of the oral glucose tolerance test (OGTT) in 445 subjects aged 30-65 years in an urban cross-sectional study in Old Ramallah. Prevalence of diabetes, sensitivity, specificity and predictive values were calculated at different cut-off levels of FCBG, using OGTT as the reference. The prevalence of OGTT-diagnosed diabetes was 2.7%, while it varied considerably using different cut-off levels of FCBG. The sensitivity of a single glucometer (Exac Tech II) measurement of FCBG at the cut-off level of 6.7 mmol 1(-1) was 33.3%, with a specificity of 98.8%. Using the cut-off level of 6.1 mmol 1(-1) as suggested by the 1998 provisional report of a WHO consultation, the sensitivity increased to 41.7%. At a cut-off level of 5.6 mmol 1(-1), a sensitivity of 66.6% was reached, but the specificity decreased slightly. It can be concluded that a single glucometer measurement of FCBG in an adult population is not useful in determining the prevalence of diabetes mellitus.