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Top POEMs of 2017: Diabetes Mellitus and Thyroid Disease

Top 20 POEMs of 2017

Home Glucose Monitoring Offers No Benefit to Patients Not Using Insulin

Clinical question
Does home monitoring of blood glucose levels improve glycemic control or quality of life in patients with type 2 diabetes who are not using insulin?

Bottom line
Lots of numbers, lots of money, lots of strips in landfills, little to show for it. Home glucose monitoring of patients in primary care does not improve hemoglobin A1c scores or quality of life over 1 year in patients who are not taking insulin. Patients did not feel more empowered or satisfied as a result of home monitoring nor have fewer hypoglycemic episodes, and their physicians did not seem to respond to the home glucose levels to any beneficial effect. (LOE = 1b)(www.essentialevidenceplus.com)

Reference
Young LA, Buse JB, Weaver MA, et al, for the Monitor Trial Group. Glucose self-monitoring in non-insulin-treated patients with type 2 diabetes in primary care settings. A randomized trial. JAMA Intern Med 2017;177(7):920-929.

Study design: Randomized controlled trial (nonblinded)

Funding source: Government

Allocation: Concealed

Setting: Outpatient (any)

Synopsis
These researchers identified adults (average age: 61 years) with type 2 diabetes not treated with insulin and hemoglobin A1c levels between 6.5% and 9.5%. Most of the patients (75%) monitored their blood glucose levels at home prior to the study but had not been seen by an endocrinologist. The 450 patients (who had type 2 diabetes for an average 8 years) were randomly assigned, using concealed allocation, to 1 of 3 arms: (1) no home glucose monitoring; (2) standard once-daily monitoring; and (3) enhanced once-daily monitoring, consisting of glucose values immediately reported to the patient plus automated, tailored messaging delivered via the meter. The patients' physicians were given the home glucose monitoring results but were not asked to follow a specific protocol to respond to them. After both 6 months and 1 year, there was no difference, on average, among the groups in hemoglobin A1c levels, hospitalizations, episodes of severe hypoglycemia, or quality of life scores. Similarly, there was no difference among groups in treatment satisfaction or feelings of empowerment.

Allen F. Shaughnessy, PharmD, MMedEd
Professor of Family Medicine
Tufts University
Boston, MA

Detrimental Effect of Tight Glucose Control on CV Mortality Persists Over 9 Years

Clinical question
What is the long-term effect of intensive blood glucose control in patients with type 2 diabetes?

Bottom line
The initial Action to Control Cardiovascular Risk in Diabetes (ACCORD) study, which compared standard treatment with intensive control, found that, despite good intentions, cardiovascular and overall mortality is significantly higher when blood glucose levels are lower. This study, which followed up patients for an additional 5 years, found that patients in the intensive treatment group continued to keep their hemoglobin A1c levels lower than in the standard care group; they also continued to be at increased risk of death from a cardiovascular event. Not good. (LOE = 2b)(www.essentialevidenceplus.com)

Reference
The ACCORD Study Group. Nine-year effects of 3.7 years of intensive glycemic control on cardiovascular outcomes. Diabetes Care 2016;39(5):701-708.

Study design: Cohort (prospective)

Funding source: Government

Setting: Outpatient (any)

Synopsis
This report is a follow-up of patients who were enrolled in the ACCORD study, which randomly assigned patients with type 2 diabetes and a high risk for cardiovascular outcomes to receive either usual care or treatment aimed at intensive control of blood glucose. After the 3.7 years of the study, patients were followed up for an additional 5 years to determine the long-term effect of their initial treatment. The patients were no longer on a protocol and their treatment goals were at the discretion of their clinician, but, A1c levels were still lower overall in the patients who had been in the intensive-care group. The investigators did a great job of keeping track of the patients, following up with 98% of them (n = 8601) who did not suffer a primary outcome or death during the original trial. Over this additional time, intensive glucose lowering did not increase or decrease the primary composite outcome of nonfatal myocardial infarction, nonfatal stroke, or cardiovascular death, death from any other cause, or overall mortality. The increased cardiovascular mortality rate seen with intensive control during the active treatment stage decreased in the subsequent years, but was still higher than in the group initially treated with standard treatment (hazard ratio 1.20; 95% CI 1.03 - 1.39; P = .02).

Allen F. Shaughnessy, PharmD, MMedEd
Professor of Family Medicine
Tufts University
Boston, MA

Screening for Pre-Diabetes: Neither HbA1c nor Fasting Glucose Results are Very Accurate

Clinical question
Are screening tests for pre-diabetes accurate?

Bottom line
"What's in a name?" Juliet pondered… to her detriment, as it turned out. So, too, with the diagnosis of "pre-diabetes." In this analysis, an elevated (by various criteria) HbA1c or fasting plasma glucose level only sometimes lines up with impaired glucose tolerance testing results via a glucose tolerance test. If we take an abnormal 2-hour glucose tolerance test result to be the true harbinger of eventual type 2 diabetes, an HbA1c level is neither sensitive or specific and a fasting glucose is specific (can accurately rule-in risk) but not sensitive. Depending on the screening test you use (or are required to use), many people will receive an incorrect diagnosis, while others will be falsely reassured. (LOE = 1a-)(www.essentialevidenceplus.com)

Reference
Barry E, Roberts S, Oke J, Vijayaraghavan S, Normansell R, Greenhalgh T. Efficacy and effectiveness of screen and treat policies in prevention of type 2 diabetes: systematic review and meta-analysis of screening tests and interventions. BMJ 2017;356:i6538.

Study design: Meta-analysis (other)

Funding source: Foundation

Setting: Various (meta-analysis)

Synopsis
The authors conducting this systematic review and meta-analysis searched several databases for all research papers that evaluated the diagnostic accuracy of laboratory-based (not office-based) HbA1c or fasting blood glucose tests to identify impaired glucose tolerance, using an oral glucose tolerance test as the reference standard for diagnosis. Heterogeneity among the studies was high, probably due to the differences in populations and settings. Across all studies the prevalence of impaired glucose tolerance was 27% but varied by study, which will make predictive values bounce around. For HbA1c tests, the sensitivity was .49 (95% CI .4 - .58) and the specificity was .79 (.73 - .84). For fasting blood glucose tests, the sensitivity was .25 (.19 - .32) and the specificity was .94 (.92 - .96). In other words, neither is very good at predicting oral glucose tolerance test results.

Allen F. Shaughnessy, PharmD, MMedEd
Professor of Family Medicine
Tufts University
Boston, MA

Treatment of Subclinical Hypothyroidism Ineffective in Older Adults

Clinical question
Is there a clinical benefit to treating subclinical hypothyroidism in older adults?

Bottom line
Treatment of patients with a minimally elevated thyrotropin (thyroid-stimulating hormone) level did not result in any improvement in symptoms. If patients present with a thyrotropin level between 4.6 mIU and 10 mIU per liter, repeat the test as the levels often normalize (this occurred in 60% of the patients initially referred for the study). Only consider treatment if levels increase to above 10.0 mIU/L. (LOE = 1b)(www.essentialevidenceplus.com)

Reference
Stott DJ, Rodondi N, Kearney PM, et al, for the TRUST Study Group. Thyroid hormone therapy for older adults with subclinical hypothyroidism. N Engl J Med 2017;376(26):2534-2544.

Study design: Randomized controlled trial (double-blinded)

Funding source: Government

Allocation: Concealed

Setting: Outpatient (any)

Synopsis
Whether to treat patients with subclinical hypothyroidism (slightly elevated thyrotropin, normal T4, and no or minimal symptoms) remains controversial. The authors of this study recruited 737 such adults, 65 years and older, and randomized them to receive thyroid replacement or matching placebo. The mean baseline thyrotropin level was 6.4 mIU/L (normal range: 0.4 to 4.59 mIU/L), and few had a value greater than 10.0 mIU/L. The groups were balanced, allocation was appropriately concealed, and analysis was by intention to treat. Patients were followed up for 1 year, and the primary outcomes were the 4-item ThyPRO thyroid symptom score and a 7-item Tiredness Score. The treatment dose of levothyroxine was started at 50 mcg daily for most patients, and gradually increased until the thyrotropin was in the normal range (the placebo group had sham titration of their "dose"). The final achieved average thyrotropin level was just over 3.0, which is a bit higher than the target 2.5 mIU/L recommended by some guidelines (Eur Thyroid J 2013;2:215-28). At the end of the study period, there was no difference in any clinical outcomes. A subset of slightly more than half the patients in each group had extended follow-up for a median of 2 years, and at that time there was a slightly greater improvement in the Tiredness Score in the levothyroxine group, but this was of marginal clinical and statistical significance. There was no difference in harms, including cardiovascular events, although the study was not powered to detect a difference if there was one.

Mark H. Ebell, MD, MS
Professor
University of Georgia
Athens, GA

POEMs are provided by Essential Evidence Plus, a point-of-care clinical decision support system published by Wiley-Blackwell. For more information, please see http://www.essentialevidenceplus.com(www.essentialevidenceplus.com).

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