Meta-analysis of individual patient data in randomised trials of self monitoring of blood glucose in people with non-insulin treated type 2 diabetes

Title: SMBG is important along with Diabetes self-management education for management of type2 Diabetes as SMBG represents thus an important adjunct to HbA1C, because it probably differentiate fasting, pre-prandial, and postprandial hyperglycemia; detect glycemic excursions; identify hypoglycaemia; and may provide immediate feedback about the effect of food choices, physical exercise, and medication on glycemic control

The author of the article says that “It is widely agreed that for further evaluation of self monitoring of blood glucose(SMBG), the therapeutic interventions and efforts to promote behavioural change should be more tightly aligned to the results obtained from self monitoring, and targeted at those likely to benefit.

Early studies linking test results to specific drug and behavioural strategies have had promising results, although not achieving the 0.5% reduction in HbA1c that is generally accepted to be of clinical relevance. Smaller reductions of HbA1c level might be of importance from a public health perspective if achieved on a wide scale and at lower cost; however, costs of self monitoring remain high, even in low and middle income countries, with the costs of unsubsidised test strips varying from $0.35 in Australia to $3.11 in India.37 Until further studies can establish potential target groups and promising interventions to improve glycaemic control with self monitoring, our meta-analysis using individual patient data does not provide convincing evidence to support its routine use for people with non-insulin treated type 2 diabetes using the range of interventions employed within the included trials.”

It is fact that in India the cost of SMBG is very high; almost for strips Rs 600-700/= per month . The bulk of patients are not in financial capacity to spend for such high cost for daily check up at least thrice a day and to have food accordingly. Moreover, glucometer and strips result give many times does not reflect true glucose value except hypoglycaemia if occur.

It is however very good to detect hypoglycaemia in type 2 diabetics also. Diabetes care according this author is complex one and requires many vital issues to tackle, beyond only glycemic control. It requires a range of interventions and support to improve diabetes control and outcomes. If the author is not wrong, in 2009, an International Expert Committee, which included representatives from the American Diabetes Association (ADA), the International Diabetes Federation (IDF), and the European Association for the Study of Diabetes (EASD) recommended the use of the HB A1C test to diagnose and monitoring diabetes, with a threshold of ≥6.5% , and ADA adopted this criterion in 2010 .

HbA1C reflects glycemic control for three months. This diagnostic test should be performed using a method that must be certified by the National Glyco-haemoglobin Standardization Program (NGSP) and NABL accredited Laboratories in West Bengal and must be standardized or traceable to the Diabetes Control and Complications Trial (DCCT) reference assay. Point-of-care HbA1C assays, for which proficiency testing is probably mandated, are not sufficiently accurate at this time to use for diagnostic purposes in many laboratories of Kolkata metropolis even and not available in urban ,district or subdivisional and rural or state general hospitals of health care system in West Bengal india. So health care providers doctors have to depend on the established glucose criteria for the diagnosis of diabetes (FPG and 2-h PBG) and it remains valid as well for drug monitoring and control .

Just as there is less than 100% concordance between the FPG and 2-h PG tests, there is not perfect concordance between A1C and either glucose-based test. Analyses of National Health and Nutrition Examination Survey (NHANES) data also indicates that, assuming universal screening of the undiagnosed, the A1C cut point of ≥6.5% identifies one-third fewer cases of undiagnosed diabetes than a fasting glucose cut point of ≥126 mg/dL (7.0 mmol/L). However, in community practice, a large portion of the diabetic population remains still unaware of their condition in West Bengal. Thus, the lower sensitivity of Hb A1C at the designated cut point may well be offset by the test's greater practicality, and wider application of a more convenient test (A1C) may actually increase the number of diagnoses made. SMBG also may be carried out three or more times daily for patients who are using multiple insulin injections or insulin pump therapy or in Type 2 DM who are on OHA.

What is to be considered as glycemic control?

Assessment of glycemic control. Two primary techniques are available for health providers doctors and patients to assess the effectiveness of the management plan on glycemic control: patient self-monitoring of blood glucose (SMBG) or interstitial glucose, and Hb A1C which is not available in most places and cost 300 to 500 Rupees in Indian currency depending on laboratories where done.

Glucose monitoring Recommendations

• For patients using less-frequent insulin injections, noninsulin OHA therapies, or medical nutrition therapy (MNT) alone, SMBG may be useful as a guide towards management on consultation with doctor.
• To achieve postprandial glucose targets, postprandial SMBG may be appropriate.
• When prescribing SMBG, one must ensure that patients receive initial instruction in, and routine follow-up evaluation of, SMBG technique and their ability to use data to adjust therapy be insulin or OHA.
• Continuous glucose monitoring (CGM) in conjunction with intensive insulin regimens can be a useful tool to lower Hb A1C in selected adults (age ≥25 years) with type 1 diabetes( Insulin Dependent & MODY).
• Although the evidence for Hb A1C-lowering is less strong in children, teens, and younger adults, CGM may be helpful in these groups. Success correlates with adherence to ongoing use of the device.
• CGM may be a supplemental tool to SMBG in those with hypoglycaemia unawareness and/or frequent hypoglycaemic episodes.

Diabetes self-management education (DSME) is the difficult one but should be an ongoing process of facilitating the knowledge about diabetes, its complications, signs and symptoms of hypoglycaemia, benefit of daily exercise, care for foot , eye , infections , behavioural changes, skill, and ability necessary for diabetes self-care. This process incorporates the needs, goals, and life experiences of the persons with diabetes and is to be guided by evidence-based standard common and consequential SMBG information, motivation, and behavioural skills deficits which is usually present. The overall objectives of DSME are to support informed decision-making, self-care behaviours, problem-solving and active collaboration with the health care doctors team and to improve clinical outcomes, health status, and quality of life style. and patients with these gaps were less likely to test thus frequently. Clinical education focusing on relevant SMBG information, motivation to act, and behavioural skills for acting effectively may be thus a priority according to me. Real-time information provided by self-monitoring of blood glucose (SMBG) represents thus an important adjunct to A1C, because it probably differentiate fasting, preprandial, and postprandial hyperglycemia; detect glycemic excursions; identify hypoglycemia; and may provide immediate feedback about the effect of food choices, physical exercise, and medication on glycemic control.

The importance of SMBG is widely thus appreciated and may be recommended as a component of management in patients with type 1 or insulin-treated type 2 diabetes, or OHA treated type2 diabetes as well as in diabetic pregnancy, for both women with pregestational type 1 and gestational diabetes. Nevertheless, and of course HbA1C is best.

Competing interests: None declared

published in BMJ

http://www.bmj.com/content/344/bmj.e486/rr/572551 as Rapid Response