Hypoglycemia in patients with diabetes who are fasting for laboratory blood tests: the Cape Girardeau Hypoglycemia En Route Prevention Program

Compatibility between an overnight fasting and random cholesterol tests in Asians

Recent Western guidelines recommend non-fasting lipid profiles to manage dyslipidaemia. We explored its applicability to an Asian population. We determined the differences between an overnight fasting and non-fasting cholesterol profiles of patients with type-2 diabetes mellitus (T2DM) in Singapore. We studied 470 multi-ethnic Asian adult patients with T2DM and dyslipidaemia from 2 primary care clinics in Singapore. Non-fasting blood specimens were collected within 6 h after their last meal and within 14 days of a fasting specimen. The intraclass correlation coefficient (ICC) was used to compare the intraindividual lipid profiles. An ICC value > 0.75 implies good correlation. The mean age and T2DM duration of the study population were 62.5 years and 9.8 years respectively. Their mean non-fasting period was 2.46 h. The mean differences between non-fasting and fasting total cholesterol (TC), high-density lipoprotein (HDL-C), triglyceride (TG), low-density lipoprotein (LDL-C), and non HDL-C were + 0.04 mmol/l, - 0.001 mmol/l, + 0.48 mmol/l, - 0.15 mmol/l, and - 0.05 mmol/l respectively. The ICC (95% CI) for TC, HDL-C, TG, LDL-C and non-HDL-C were 0.820 (0.788-0.847), 0.873 (0.850-0.893), 0.579 (0.516-0.636), 0.764 (0.723-0.799), and 0.825 (0.794-0.852) respectively. The fasting and non-fasting lipid profiles were similar in our local Asian patients with T2DM taking statin. Their non-fasting lipid profile can be used to assess their cholesterol treatment status.

Fasting-Evoked En Route Hypoglycemia in Diabetes (FEEHD): From Guidelines to Clinical Practice

BACKGROUND

Lipid profiles have been used for the purposes of health screening and monitoring of the effects of lipid-lowering medications, especially in patients with diabetes who are prone to hyperlipidemia. Fasting for lipid profiles has been the norm for the past decades. This long-lasting tradition poses a risk of hypoglycemia, especially in patients with diabetes.

OBJECTIVE

Our aim is to review the overlooked occurrence of hypoglycemia in patients who fast for laboratory tests, especially lipid profile tests, and commute to the laboratory facility while fasting; a condition we titled "Fasting-Evoked En route Hypoglycemia in Diabetes patients" or "FEEHD". We also review its prevalence and clinical impact on patients with diabetes.

METHODS

We undertook an extensive literature search using search engines such as PubMed and Google Scholar. We used the following keywords for the search: Fasting, Non-fasting; Hypoglycemia; Hypoglycemic Agents; Laboratory Tests; Glucose, Hypoglycemia, Lipid Profiles, FEEHD.

RESULTS

Our literature review has shown that the prevalence of FEEHD is alarmingly high (17-21% of patients at risk). This form of hypoglycemia is under recognized in the clinical practice despite its frequent occurrence. Recent changes in various international guidelines have uniformly endorsed the utilization of non-fasting lipid profiles as the new standard for obtaining lipid profiles with the exception of certain conditions. Multiple studies showed the efficacy of non-fasting lipid tests in comparison to fasting lipid tests, in routine clinical practice.

CONCLUSION

We hope to increase awareness among clinicians about this overlooked and potentially harmful form of hypoglycemia in patients with diabetes, which can be easily avoided. We also hope to call upon clinicians to consider changing the habit of ordering lipid profiles in the fasting state, which has been recently shown to be largely unnecessary in routine clinical settings, with few exceptions in selected cases.

Hypoglycemia Among Patients with Type 2 Diabetes: Epidemiology, Risk Factors, and Prevention Strategies

PURPOSE OF REVIEW

Hypoglycemia is the most common and often treatment-limiting serious adverse effect of diabetes therapy. Despite being potentially preventable, hypoglycemia in type 2 diabetes incurs substantial personal and societal burden. We review the epidemiology of hypoglycemia in type 2 diabetes, discuss key risk factors, and introduce potential prevention strategies.

RECENT FINDINGS

Reported rates of hypoglycemia in type 2 diabetes vary widely as there is marked heterogeneity in how hypoglycemia is defined, measured, and reported. In randomized controlled trials, rates of severe hypoglycemia ranged from 0.7 to 12 per 100 person-years. In observational studies, hospitalizations or emergency department visits for hypoglycemia were experienced by 0.2 (patients treated without insulin or sulfonylurea) to 2.0 (insulin or sulfonylurea users) per 100 person-years. Patient-reported hypoglycemia is much more common. Over the course of 6 months, 1-4% non-insulin users reported need for medical attention for hypoglycemia; 1-17%, need for any assistance; and 46-58%, any hypoglycemia symptoms. Similarly, over a 12-month period, 4-17% of insulin-treated patients reported needing assistance and 37-64% experienced any hypoglycemic symptoms. Hypoglycemia is most common among older patients with multiple or advanced comorbidities, patients with long diabetes duration, or patients with a prior history of hypoglycemia. Insulin and sulfonylurea use, food insecurity, and fasting also increase hypoglycemia risk. Clinical decision support tools may help identify at-risk patients. Prospective trials of efforts to reduce hypoglycemia risk are needed, and there is emerging evidence supporting multidisciplinary interventions including treatment de-intensification, use of diabetes technologies, diabetes self-management, and social support. Hypoglycemia among patients with type 2 diabetes is common. Patient-centered multidisciplinary care may help proactively identify at-risk patients and address the multiplicity of factors contributing to hypoglycemia occurrence.

Fasting-Evoked En Route Hypoglycemia in Diabetes (FEEHD): An Overlooked Form of Hypoglycemia in Clinical Practice

OBJECTIVE

Many patients with diabetes opt to fast for lab tests, especially for lipid profiles, thus missing breakfast. In parallel, recent studies and international guidelines have indicated that routine fasting for lipid panels may not be necessary. Missing breakfast while fasting for lab tests may invoke hypoglycemia, if patients are not properly instructed about adjusting diabetes medications on the night before or on the day of the lab test. Our group described this form of hypoglycemia and introduced the term FEEHD to refer to it (fasting-evoked en route hypoglycemia in diabetes). In a recently published small study, we reported a rate of occurrence of FEEHD of 27.1%. The objective of this study was to evaluate the rate of occurrence of FEEHD in another clinic.

METHODS

Patients with diabetes were asked to complete a simple, 2-page survey inquiring about hypoglycemic events while fasting for labs in the preceding 12 months.

RESULTS

A total of 525 patients completed the surveys out of 572 patients invited (91.8% response rate). A total of 363 patients with complete data were analyzed, with a mean age of 60.6 (SD 12.5) years. A total of 62 (17.1%) patients reported having experienced one or more FEEHD events in the prior 12 months. Of the 269 patients who were at higher risk of FEEHD (on insulin secretagogues or on insulin), 59 (21.9%) reported having experienced FEEHD. Only 33 of FEEHD patients (53%) recalled having contacted their provider regarding the events and only 22 (35%) indicated having received some sort of FEEHD prevention instructions.

CONCLUSION

Our study shows a significant rate of occurrence of FEEHD in the real world (a clinical practice). FEEHD is especially dangerous, as patients often commute (drive) to and from the laboratory facility (potential risk of traffic accidents). Given study limitations, further studies are needed to assess prevalence of FEEHD in other settings and in the general populations.

The traditions and risks of fasting for lipid profiles in patients with diabetes

Fasting overnight has been traditionally recommended by clinicians when ordering laboratory tests for lipid profiles for the purposes of health screening or monitoring of the effects of lipid-lowering medications. Patients with diabetes are tested for lipid profiles at least annually. This deeply rooted tradition of fasting for lipid testing has recently been challenged. Several studies have shown little benefit obtained by testing lipids in fasting compared with postprandial states. Furthermore, recent studies have shown the importance of postprandial lipid spikes in the pathogenesis of cardiovascular disease. At the same time, recent reports have alerted the medical community to the risk of hypoglycemia in patients with diabetes on antidiabetic medications (particularly insulin and sulfonylureas) who are asked to fast for lab tests. This article reviews the literature on these emerging issues in lipid testing in patients with diabetes, and offers recommendations for lipid testing in these patients in view of these emerging discussions.