XI. STRATEGIES FOR IMPROVING DIABETES CARE D iabetes is a chronic illness that requires continuing medical care and patient self-management education to prevent acute complications and to reduce the risk of long-term complications. Diabetes care is complex and requires that many issues, beyond glycemic control, be addressed. A large body of evidence exists that supports a range of interventions to improve diabetes outcomes. These standards of care are intended to provide clinicians, patients, researchers, payors, and other interested individuals with the components of diabetes care, treatment goals, and tools to evaluate the quality of care. While individual preferences, comorbidities, and other patient factors may require modification of goals, targets that are desirable for most patients with diabetes are provided. These standards are not intended to preclude more extensive evaluation and management of the patient by other specialists as needed. For more detailed information, refer to Bode (Ed.): Medical Management of Type 1 Diabetes (1), Burant (Ed): Medical Management of Type 2 Diabetes (2), and Klingensmith (Ed): Intensive Diabetes Management (3). The recommendations included are diagnostic and therapeutic actions that are known or believed to favorably affect health outcomes of patients with diabetes. A grading system (Table 1), developed by the American Diabetes Association (ADA) and modeled after existing methods, was utilized to clarify and codify the evidence that forms the basis for the recommendations. The level of evidence that supports each recommendation is listed after each recommendation using the letters A, B, C, or E.

Standards of Medical Care in Diabetes

25. Multiple Imputation for Nonresponse in Surveys. By D. B. Rubin. ISBN 0 471 08705 X. Wiley, Chichester, 1987. 258 pp. £30.25.

Multiple Imputation for Nonresponse in Surveys

We investigate conditions sufficient for identification of average treatment effects using instrumental variables. First we show that the existence of valid instruments is not sufficient to identify any meaningful average treatment effect. We then establish that the combination of an instrument and a condition on the relation between the instrument and the participation status is sufficient for identification of a local average treatment effect for those who can be induced to change their participation status by changing the value of the instrument. Finally we derive the probability limit of the standard IV estimator under these conditions. It is seen to be a weighted average of local average treatment effects.

Evolution and Rationality Some Recent Game-Theoretic Results. Identification and Estimation of Local Average Treatment Effects

The 2015 American Geriatrics Society (AGS) Beers Criteria are presented. Like the 2012 AGS Beers Criteria, they include lists of potentially inappropriate medications to be avoided in older adults. New to the criteria are lists of select drugs that should be avoided or have their dose adjusted based on the individual's kidney function and select drug–drug interactions documented to be associated with harms in older adults. The specific aim was to have a 13‐member interdisciplinary panel of experts in geriatric care and pharmacotherapy update the 2012 AGS Beers Criteria using a modified Delphi method to systematically review and grade the evidence and reach a consensus on each existing and new criterion. The process followed an evidence‐based approach using Institute of Medicine standards. The 2015 AGS Beers Criteria are applicable to all older adults with the exclusion of those in palliative and hospice care. Careful application of the criteria by health professionals, consumers, payors, and health systems should lead to closer monitoring of drug use in older adults.

American Geriatrics Society 2015 Updated Beers Criteria for Potentially Inappropriate Medication Use in Older Adults

https://www.thelancet.com/pdfs/journals/lancet/PIIS0140-6736(13)62154-6.pdf

Pathophysiology and treatment of type 2 diabetes: perspectives on the past, present, and future

Objective: To estimate risk and relative risk (RR) of acute pancreatitis among patients using incretin-based diabetes therapies (exenatide or sitagliptin) compared to patients treated with agents w...

Use of a claims-based active drug safety surveillance system to assess the risk of acute pancreatitis with exenatide or sitagliptin compared to metformin or glyburide.

Aim: Reports of acute pancreatitis associated with exenatide treatment prompted this study to estimate the association between acute pancreatitis and exenatide use relative to other antihyperglycaemic drugs.



Methods: This cohort study included patients without claims for prior pancreatic disease who initiated exenatide or other antihyperglycaemic drugs between June 2005 and December 2007. Acute pancreatitis was identified with diagnosis codes and confirmed through review of blinded medical records. Poisson regression models provided estimates of rate ratios (RRs) and 95% confidence intervals (CIs) comparing the rate of acute pancreatitis during periods of current (days supplied + 31 days), recent (current definition + 31 days) and past use (≥32 days beyond current definition) of exenatide relative to other antihyperglycaemic drugs, adjusted for propensity scores. A prespecified nested case–control analysis provided RR estimates adjusted for patient characteristics abstracted from medical records.



Results: Initiators of exenatide (N = 25719) had more baseline claims for obesity and concomitant diabetes drugs than comparators (N = 234536). There were 40 confirmed cases of acute pancreatitis in the exenatide cohort and 254 among other antihyperglycaemic drug initiators. Compared to other antihyperglycaemic drugs, the propensity score-adjusted RR for exenatide was 0.5 (95% CI 0.2–0.9) for current use, 1.1 (95% CI 0.4–3.2) for recent use and 2.8 (95% CI 1.6–4.7) for past use. The case–control analysis resulted in a RR of 0.2 for current use (95% CI 0.0–1.4) and 0.1 for recent use (95% CI 0.0–1.3), but an attenuated RR in the past use association (RR 1.1; 95% CI 0.1–11.0).



Conclusions: Exenatide use was not associated with an increased risk of acute pancreatitis.

A cohort study of acute pancreatitis in relation to exenatide use

Importance It is important to understand the relationship between sleep medication use and injurious falls in nursing home residents. Objective To conduct a case-crossover study to estimate the association between nonbenzodiazepine hypnotic drug use (zolpidem tartrate, eszopiclone, or zaleplon) and the risk for hip fracture among a nationwide sample of long-stay nursing home residents, overall and stratified by individual and facility-level characteristics. Design and Setting Case-crossover study performed in an academic research setting. Participants The study participants included 15 528 long-stay US nursing home residents 50 years or older with a hip fracture documented in Medicare Part A and Part D fee-for-service claims between July 1, 2007, and December 31, 2008. Main Outcome Measures Odds ratios (ORs) of hip fracture were estimated using conditional logistic regression models by comparing the exposure to nonbenzodiazepine hypnotic drugs during the 0 to 29 days before the hip fracture (hazard period) with the exposure during the 60 to 89 and 120 to 149 days before the hip fracture (control periods). Analyses were stratified by individual and facility-level characteristics. Results Among the study participants, 1715 (11.0%) were dispensed a nonbenzodiazepine hypnotic drug before the hip fracture, with 927 exposure-discordant pairs included in the analyses. The mean (SD) age of participants was 81.0 (9.7) years, and 77.6% were female. The risk for hip fracture was elevated among users of a nonbenzodiazepine hypnotic drug (OR, 1.66; 95% CI, 1.45-1.90). The association between nonbenzodiazepine hypnotic drug use and hip fracture was somes greater in new users (OR, 2.20; 95% CI, 1.76-2.74) and in residents with mild vs moderate to severe impairment in cognition (OR, 1.86 vs 1.43; P = .06), with moderate vs total or severe functional impairment (OR, 1.71 vs 1.16; P = .11), with limited vs full assistance required with transfers (OR, 2.02 vs 1.43; P = .02), or in a facility with fewer Medicaid beds (OR, 1.90 vs 1.46; P = .05). Conclusions and Relevance The risk for hip fracture is elevated among nursing home residents using a nonbenzodiazepine hypnotic drug. New users and residents having mild to moderate cognitive impairment or requiring limited assistance with transfers may be most vulnerable to the use of these drugs. Caution should be exercised when prescribing sleep medications to nursing home residents.

https://jamanetwork.com/journals/jamainternalmedicine/articlepdf/1657760/iiq130125_754_761.pdf

Nonbenzodiazepine sleep medication use and hip fractures in nursing home residents.

Extended case-control study results on thromboembolic outcomes among transdermal contraceptive users.

Self-matched case-only studies (such as the case-crossover or self-controlled case-series method) control by design for time-invariant confounders (measured or unmeasured), but they do not control for confounders that vary with time. A bidirectional case-crossover design can be used to adjust for exposure-time trends. In pharmacoepidemiology, however, illness often influences future use of medications, making a bidirectional design problematic. Suissa's case-time-control design combines a case-crossover and case-control design, and adjusts for exposure-trend bias in the cases' self-controlled odds ratio by dividing that ratio by the corresponding self-controlled odds ratio in a concurrent matched control group. However, if not well matched, the control group may reintroduce selection bias. We propose a "case-case-time-control" that involves crossover analyses in cases and future-case controls. This person-time sampling strategy improves matching by restricting controls to future cases. We evaluate the proposed study design through simulations and analysis of a theoretically null relationship using Veterans Administration (VA) data. Simulation studies show that the case-case-time-control can adjust for exposure trends while controlling for time-invariant confounders. Use of an inappropriate control group left case-time-control analyses biased by exposure-time trends. When analyzing the relationship between vitamin exposure and stroke, using data on 3192 patients in the VA system, a case-crossover odds ratio of 1.5 (95% confidence interval = 1.3-1.7) was reduced to 1.1 (0.9-1.3) when divided by the concurrent exposure trend odds ratio (1.4) in matched future cases. This applied example demonstrates how our approach can adjust for exposure trends observed across time axes.

David D. Dore

Papers

Use of a claims-based active drug safety surveillance system to assess the risk of acute pancreatitis with exenatide or sitagliptin compared to metformin or glyburide.

A cohort study of acute pancreatitis in relation to exenatide use

Nonbenzodiazepine sleep medication use and hip fractures in nursing home residents.

Extended case-control study results on thromboembolic outcomes among transdermal contraceptive users.

Future cases as present controls to adjust for exposure trend bias in case-only studies.