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Introduction: Monitoring of glycemic control includes daily monitoring of glucose at home as well as periodic monitoring of overall glycemia. The aims of monitoring glycemic control are: To assess with accuracy and precision the level of glycemic control achieved by each individual so that they may benefit from attaining their most realistic glycemic targets (1, 2) (A). To help in preventing both the acute complication of hypoglycemia and the chronic complications of microvascular and macrovascular diseases (A). To minimize the effect of hypoglycemia (A) and hyperglycemia (B/C) on cognitive function and mood. To collect data on glycemic control from each diabetes center for comparison with stated local, national, and international standards so that the performance and standards of the interdisciplinary Diabetes Care Teams may be improved (3). Measurement of immediate glycemic control is best determined by self-monitoring of blood glucose (SMBG) as this provides immediate documentation of hyperglycemia and hypoglycemia, allowing implementation of strategies to optimally treat, as well as to avoid, out of range glucose values. Hemoglobin A1c (HbA1c) is the only measure of glycemic control for which robust outcome data are available. Elevated HbA1c predicts long-term microvascular and macrovascular outcomes (1, 2) (A). However, HbA1c has limitations as a measure of glycemic control, i.e., average blood glucose (BG). In the Diabetes Control and Complications Trial (DCCT) 96% of complications were explained by variations in HbA1c (4) However, HbA1c of 7.0% corresponded to a higher average BG (measured seven times a day) of 192 mg/dL (10.7 mmol/L) in the conventionally treated patients vs. 163 mg/dL (9 mmol/L) in the intensively treated patients (6). HbA1c can only be one of the several measures of optimal glycemic control, along with documented hypoglycemia, type of treatment, patient's age, and quality of life. The DCCT, and similar studies, provides clear evidence in adults and adolescents that better metabolic control, as measured by a lower HbA1c level, is associated with fewer and delayed microvascular complications (1, 2, 7–15). The DCCT also showed that patients in the intensive treatment group had less risk of retinopathy than the conventional group even when having the same HbA1c (4). Additional studies have shown that frequent and accurate BG monitoring and concomitant optimal adjustment of insulin to carbohydrate intake and exercise (16, 17) are required to attain and to maintain optimal metabolic control. Finally, follow-up data from the DCCT indicate that 5–7 yr of poor glycemic control, even during adolescence and young adulthood, results in an increased risk for microvascular and macrovascular complications in the subsequent 6–10 yr (7, 9, 13, 14, 18). These data support trying to achieve for each individual an HbA1c as close to the normal range as possible. Both hypoglycemia and hyperglycemia may result in central nervous system (CNS) alterations, both acutely and chronically. Lower HbA1c levels may be associated with an increase in episodes of severe hypoglycemia (1, 2) (A). Severe hypoglycemia is a significant cause for morbidity and occasional mortality in young people with type 1 diabetes (19–22). Most, but not all, studies have shown that repeated episodes of hypoglycemic seizures in young children may cause permanent CNS changes and/or cognitive dysfunction (23–30). Additionally, the long-term follow-up of the DCCT participants has been reassuring that there was no evidence for permanent neurocognitive changes related to hypoglycemia in adolescent and young adult individuals, suggesting that the effect of severe hypoglycemia on long-term neuropsychological functioning may be age dependent (31, 32). Regardless of the long-term sequelae of hypoglycemia, the fear of hypoglycemia has been shown to cause intentional decreases in insulin dosing, resulting in elevated glucose levels and increased HbA1c (33). Conversely, there is evidence that chronic hyperglycemia (particularly in young boys) might be related to poorer neurocognitive outcomes (34) (B). Acute hyperglycemia (BG > 15 mmol/L) is associated with reduced motor cognitive performance in a field study of adults with type 1 diabetes (35) (B), confirming findings using clamp studies in children of reduced performance when BG was > 20 mmol/L compared with 5–10 mmol/L (36) (B). Families report effects of hyperglycemia (15–18 mmol/L) on mood and coordination (37) (C). Long-term studies on hyperglycemia and cognitive functioning are not available. Brain imaging studies show that both hypoglycemia and hyperglycemia cause changes in the white and gray matter of developing brains (38). There is evidence for CNS changes in children with diabetes associated with hyperglycemia as well as hypoglycemia, although the cognitive functioning and brain imaging findings in children with diabetes as a whole are not significantly different from healthy control children (38, 39). The CNS changes in association with hyperglycemia are relatively new findings but are consistent with reported neurocognitive findings (34). One theory is that chronic hyperglycemia during the early years before age 5, when the brain is still developing, will affect it negatively with white matter dysfunction due to a non-optimal myelinization. This makes the brain more vulnerable to any subsequent insult, including hypoglycemia, that occurs later in the child's life (40) [E]. Experts agree that at present, safest recommendation for improving glycemic control generally in all children is to achieve the lowest HbA1c that can be sustained without disabling or severe hypoglycemia while avoiding prolonged periods of significant hyperglycemia (BG levels > 15–20 mmol/L) (35–37) and episodes of diabetic ketoacidosis (DKA) and that these goals can only be achieved by some form of frequent glucose monitoring. SMBG helps to monitor immediate and daily levels of control; helps to determine immediate and daily insulin requirements; helps guide insulin adjustments to decrease fluctuations in BG levels; detects hypoglycemia and assists in its management; and assists in the safe management of hyperglycemia. The frequency of SMBG is associated with improved HbA1c in patients with type 1 diabetes (41) (A) (16, 17,42–46) (B). This is thought to be because of both better insulin adjustment for food consumed and an improved ability to quickly correct out-of-target glucose values. In addition, early detection of lower glucose values prior to symptomatic hypoglycemia may allow correction with a decreased risk of overcorrection and resultant hyperglycemia. The use of SMBG during exercise may also allow improved insulin management and a decreased risk for hypoglycemia during and following exercise (47). Patient acceptance of SMBG may be enhanced by including the opportunity for testing alternative sites in addition to the fingertips, e.g., the palm of the hand or the forearm. In the fasting state, glucose readings from the forearm are similar to the fingertip (48) (B). These alternative sites may be slower to reflect falling BG levels, so it is advised that fingertips are used when symptoms of hypoglycemia are present and to recheck the glucose using the fingertip if the alternative site test is in a low range (49) (B). Equipment. There are many types of excellent monitors for SMBG; however, significant inaccuracies may arise from operator-related errors (50). Health care professionals should choose and advise on a type that is robust, precise, accurate, and familiar to them as well as affordable to the patient. Timing of SMBG. BG is best measured at different times in the day to show levels of BG after the overnight fast, during the night to detect unnoticed hypoglycemia and hyperglycemia, in response to the action profiles of insulin (at anticipated peaks and troughs of insulin action), and after food intake (1.5–2 h after a meal), and in association with vigorous sport or exercise (during and several hours after) so that changes may be made in management to improve BG profiles (45, 51, 52) (B); to confirm hypoglycemia and to monitor recovery; and during intercurrent illness to prevent hyperglycemic crises. The number and regularity of SMBG should be individualized depending on availability of equipment; type of insulin regimen; and ability of the child to identify hypoglycemia. Note: successful application of intensified diabetes management with multiple injection therapy or insulin infusion therapy requires frequent SMBG (four to six times a day) and regular, frequent review of the results to identify patterns requiring adjustment to the diabetes treatment plan. Targets. The targets are intended as guidelines. There is little age-related scientific evidence for strict glucose targets (Table 1). However, each child should have their targets individually determined with the goal of achieving a value as close to normal as possible while avoiding severe hypoglycemia as well as frequent mild to moderate hypoglycemia (E). It is recognized that in many countries, urine glucose monitoring is the only monitoring method available and that it provides useful but different information from SMBG (53) (B). Urinary glucose reflects glycemic levels over the preceding several hours and is affected by the renal threshold for glucose, which in children is approximately 10–11 mmol/L (180–200 mg/dL) (54). Periodic, quantitative, timed urine glucose determinations to include different times of the day, e.g., from dinner until bed, overnight until arising, etc., can allow determination of grams of glucose excreted during these times and may increase the usefulness of urine glucose determinations (E). Limitations of urine glucose monitoring include uncertain correlation with BG levels; inability to detect hypoglycemia or monitor response to treatment of hypoglycemia; less valuable as an educational tool to identify glycemic patterns; and unhelpful in hyperglycemic crises because of the lag phase between recovery and changes in urine glucose. Target. As many urine tests as possible should show no glycosuria without the occurrence of frequent or severe hypoglycemia (E). Equipment. Glucose oxidase strips that are relatively inexpensive, convenient, and safe. Some non-specific reducing agent methods are used such as Clinitest tablets or Benedict's test. These are less convenient to use and are also potentially dangerous if the chemical reagents come into contact with the skin, esophagus, or gastrointestinal tract. Intermittent BG monitoring, SMBG, determines the capillary glucose level at the moment when the test is performed, generally two to six times a day. Minimally invasive devices are available, and others are in development that measure interstitial fluid glucose every 1–20 min, i.e., ‘continuous’ measurement. Currently, these devices are expensive and may not be available in many countries. Insurance coverage is also limited. Over time, these devices are becoming more widely available and, with greater evidence of efficacy, may be covered by both national and private insurance. As continuous glucose monitoring becomes more widely available, it is anticipated that decreased BG targets may be achieved more safely, allowing further decreases in target HbA1c levels and improved outlooks for children with diabetes (55, 56). Minimally invasive sensors use a catheter or a small plastic chip containing a sensor inserted into the subcutaneous space to measure the interstitial glucose. They are replaced every and two to times daily using SMBG These sensors glucose levels to a or to an insulin infusion for by the The continuous glucose results are available to the during the monitoring and are in the or for to a at a later The the and/or the to review the results and insulin The review of the continuous glucose monitoring results is a tool for the effects of insulin and exercise on glucose In addition, delayed devices for use are available to and management sensor devices may guide adjustments of insulin and can identify times of consistent hyperglycemia and times of increased risk for hypoglycemia a more to home SMBG (A). Both the and delayed devices have been in management following of insulin infusion and of hypoglycemia and hyperglycemia (B). These devices have been used in to frequency of hypoglycemia and strategies to decrease its during and following in these studies has information that improved for insulin management for all with diabetes including not using continuous Some devices allow targets to be so that an will the to a glucose value to or the target in min, on the of of the interstitial glucose use of blood glucose values decrease and in the hypoglycemic range also decreases These results the that that with more use of continuous glucose monitoring, decreased blood glucose targets be allowing further decreases in target HbA1c levels and improved for children with type 1 However, studies in use of sensors have in improved glucose control with frequent adolescents may not be to a as or for as prolonged a of as is required to result in improved glucose the frequency of sensor use over a predicts the HbA1c effect of the These results indicate is to that is less in a life and to identify to help adolescents to required to maintain optimal glucose or blood should be during episodes of hyperglycemia, insulin intercurrent illness and ketoacidosis (E). determination has been shown to be more in avoiding than urine determinations (B). for or urine testing strips for testing are available, which detect increased levels of in lower than of mmol/L to mmol/L to mmol/L to and mmol/L to of urine or levels in the of hyperglycemia indicate insulin and risk for metabolic to The of with hyperglycemia and be to be because of and requires further (E). in to blood is not in out or for blood are available for blood testing and can also be used for capillary BG testing different the strips are many advise using the blood testing for young in it is more to a urine or for any age individual if the urine is testing is for patients as they have a subcutaneous insulin of blood levels can guide e.g., if therapy can be or if more intensive treatment is required to severe ketoacidosis mmol/L is and no action is mmol/L is but quickly to containing carbohydrate if BG is injection of a insulin if BG is elevated to mmol/L mg/dL) or mmol/L risk of but can be with and injection of a insulin diabetes or should be > mmol/L is by contact with diabetes or is for for more Note: BG levels be before insulin in patients with or or blood may be elevated in diabetic patients as a metabolic response to low carbohydrate during prolonged or as well as in and in BG levels are normal or low in these and insulin is not To correct the metabolic containing with low glucose and may be used when BG levels are mg/dL The of the fluid should be increased further when BG is mg/dL However, if is > insulin is the BG level has after for for more testing should be when there is illness with and/or the BG value mmol/L mg/dL) in an child be in with the day or there are BG levels mmol/L in a young an insulin or a with a of prior episodes of Additionally, if there is with elevated BG or urine glucose, and or risk for should be with It is for a monitoring or some type of to be used to patterns of glycemic control and adjustments to The is useful at the of and should and of BG levels; insulin of glycemic control hypoglycemic of and in the to help the cause for the and episodes of Monitoring should not be used as a but as a for the of and strategies for improving glycemic control (E). home review of to identify patterns in glycemic levels and subsequent adjustment in diabetes management are required for successful intensified diabetes management (E). In some monitoring is the has to a and can the BG monitoring data for this may for a although of management may be with this method (E). Glucose becomes to the of during the life of the is approximately or HbA1c reflects levels of over the preceding the most However, the most is not because the most is HbA1c monitoring has been shown to be the most useful measure in metabolic control and is the only measure for which data are available in of its with later microvascular and macrovascular complications (1, 2) (A). and normal range for children should be available. There should be quality control with national and DCCT It is that scientific also HbA1c in DCCT if the is not to these (E). It is that a capillary method for of the child's blood is available and that the HbA1c result is available at the of the so that immediate adjustments in management can be on the HbA1c method using a has been shown to results to methods (E). for the of HbA1c should be available to all for young people with diabetes (E). of will on and child should have a of one there should be to six in children and to in children (E). with type diabetes should have two to because adolescents may insulin requiring more than adults (E). HbA1c target range for all of is (Table 1). These targets are intended as guidelines. child should have their targets individually determined with the goal of achieving a value as close to normal as possible while avoiding severe hypoglycemia as well as frequent mild to moderate hypoglycemia. The goal is to the long-term microvascular and macrovascular complications of diabetes while also avoiding sequelae of acute hypoglycemia and the CNS changes associated with both hypoglycemia and hyperglycemia. from the DCCT is available for and for children can only be determined using these data and The intensively treated adolescent of the DCCT achieved a HbA1c of while in the adult achieved a HbA1c of in the follow-up of Diabetes and Complications an average HbA1c of of DCCT during the yr of follow-up reported to In addition, a of children should to achieve an HbA1c the normal range at some in the after (during the generally between 1 and after In many studies, there is evidence of an increased risk for hypoglycemia as the HbA1c decreases (1, 2) (A) but this is not the (C). control and the risk of hypoglycemia may be decreased by the of insulin and the frequency of BG monitoring. for HbA1c are with the that will be to severe hypoglycemia. severe hypoglycemia is more when hypoglycemia is present, HbA1c targets be increased when hypoglycemia In individuals, are at a glucose level of mmol/L while symptoms of hypoglycemia at a of mmol/L mg/dL) and cognitive dysfunction at mmol/L mg/dL) hypoglycemia in with diabetes is as the occurrence of a glucose value > mmol/L mg/dL) without or symptoms of group this level to subsequent hypoglycemia (B). is as before and can be associated with reduced of the of hypoglycemia It occurs when a or hypoglycemic to a significant decrease in of hypoglycemia is more in maintain generally lower BG levels monitoring devices are becoming available that may benefit with hypoglycemic as the devices will when glucose is a range or with of of glucose. There is evidence that of of hypoglycemia can be by avoiding hypoglycemia for although this is for young and should be in the and symptoms of hypoglycemia and a for hypoglycemia should be at every diabetes care (E). The children are at increased risk for outcomes from severe hypoglycemia, and because they are to hypoglycemia, in achieving lower targets for children is In many that the average HbA1c is in lowest in this the more at As adulthood, targets similar to of the adult should be that the and adjustments of adolescence achieving these targets all adolescents are the from achieving HbA1c the diabetes that the increased in diabetes care during the adolescent as well as the effect of and of However, results from the DCCT and the follow-up studies that poor control for 5–7 yr that is similar to the of may have prolonged effects (7, 9, 13, 14, (A). better insulin and glucose monitors are available compared with the DCCT adolescents at may still be to achieve a lower HbA1c levels than the DCCT adolescent average without to care in this goals may to an of and on of many patients (E). 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