Continuous Glucose Monitor Metrics Are Associated with Emergency Department Visits and Hospitalizations for Hypoglycemia and Hyperglycemia, But Have Low Predictive Value

Objective: Determine whether continuous glucose monitor (CGM) metrics can provide actionable advance warning of an emergency department (ED) visit or hospitalization for hypoglycemic or hyperglycemic (dysglycemic) events. Research Design and Methods: Two nested case-control studies were conducted among insulin-treated diabetes patients at Kaiser Permanente, who shared their CGM data with their providers. Cases included dysglycemic events identified from ED and hospital records (2016-2021). Controls were selected using incidence density sampling. Multiple CGM metrics were calculated among patients using CGM >70% of the time, using CGM data from two lookback periods (0-7 and 8-14 days) before each event. Generalized estimating equations were specified to estimate odds ratios and C-statistics. Results: Among 3626 CGM users, 108 patients had 154 hypoglycemic events and 165 patients had 335 hyperglycemic events. Approximately 25% of patients had no CGM data during either lookback; these patients had >2 × the odds of a hypoglycemic event and 3-4 × the odds of a hyperglycemic event. While several metrics were strongly associated with a dysglycemic event, none had good discrimination. Conclusion: Several CGM metrics were strongly associated with risk of dysglycemic events, and these can be used to identify higher risk patients. Also, patients who are not using their CGM device may be at elevated risk of adverse outcomes. However, no CGM metric or absence of CGM data had adequate discrimination to reliably provide actionable advance warning of an event and thus justify a rapid intervention.

Willingness to take less medication for type 2 diabetes among older patients: The Diabetes & Aging Study

BACKGROUND

To examine the willingness of older patients to take less diabetes medication (de-intensify) and to identify characteristics associated with willingness to de-intensify treatment.

METHODS

Survey conducted in 2019 in an age-stratified, random sample of older (65-100 years) adults with diabetes on glucose-lowering medications in the Kaiser Permanente Northern California Diabetes Registry. We classified survey responses to the question: "I would be willing to take less medication for my diabetes" as willing, neutral, or unwilling to de-intensify. Willingness to de-intensify treatment was examined by several clinical characteristics, including American Diabetes Association (ADA) health status categories used for individualizing glycemic targets. Analyses were weighted to account for over-sampling of older individuals.

RESULTS

A total of 1337 older adults on glucose-lowering medication(s) were included (age 74.2 ± 6.0 years, 44% female, 54.4% non-Hispanic white). The proportions of participants willing, neutral, or unwilling to take less medication were 51.2%, 27.3%, and 21.5%, respectively. Proportions of willing to take less medication varied by age (65-74 years: 54.2% vs. 85+ years: 38.5%) and duration of diabetes (0-4 years: 61.0% vs. 15+ years: 44.2%), both p < 0.001. Patients on 1-2 medications were more willing to take less medication(s) compared with patients on 10+ medications (62.1% vs. 46.6%, p = 0.03). Similar proportions of willingness to take less medications were seen across ADA health status, and HbA1c. Willingness to take less medication(s) was similar across survey responses to questions about patient-clinician relationships.

CONCLUSIONS

Clinical guidelines suggest considering treatment de-intensification in older patients with longer duration of diabetes, yet patients with these characteristics are less likely to be willing to take less medication(s).

Glycemic control and diabetes complications across health status categories in older adults treated with insulin or insulin secretagogues: The Diabetes & Aging Study

BACKGROUND

For older adults with type 2 diabetes (T2D) treated with insulin or sulfonylureas, Endocrine Society guideline recommends HbA1c between 7% to <7.5% for those in good health, 7.5% to <8% for those in intermediate health, and 8% to <8.5% for those in poor health. Our aim was to examine associations between attained HbA1c below, within (reference), or above recommended target range and risk of complication or mortality.

METHODS

Retrospective cohort study of adults ≥65 years old with T2D treated with insulin or sulfonylureas from an integrated healthcare delivery system. Cox proportional hazards models of complications during 2019 were adjusted for sociodemographic and clinical variables. Primary outcome was a combined outcome of any microvascular or macrovascular event, severe hypoglycemia, or mortality during 12-month follow-up.

RESULTS

Among 63,429 patients (mean age: 74.2 years, 46.8% women), 8773 (13.8%) experienced a complication. Complication risk was significantly elevated for patients in good health (n = 16,895) whose HbA1c was above (HR 1.97, 95% CI 1.62-2.41) or below (HR 1.29, 95% CI 1.02-1.63) compared to within recommended range. Among those in intermediate health (n = 30,129), complication risk was increased for those whose HbA1c was above (HR 1.45, 95% CI 1.30-1.60) but not those below the recommended range (HR 0.99, 95% CI 0.89-1.09). Among those in poor health (n = 16,405), complication risk was not significantly different for those whose HbA1c was below (HR 0.98, 95% CI 0.89-1.09) or above (HR 0.96, 95% CI 0.88-1.06) recommended range.

CONCLUSIONS

For older adults with T2D in good health, HbA1c below or above the recommended range was associated with significantly elevated complication risk. However, for those in poor health, achieving specific HbA1c levels may not be helpful in reducing the risk of complications.

Racial and Ethnic Differences in the Association Between Mean Glucose and Hemoglobin A1c

Background: Studies have reported significantly higher hemoglobin A1c (A1C) in African American patients than in White patients with the same mean glucose, but less is known about other racial/ethnic groups. We evaluated racial/ethnic differences in the association between mean glucose, based on continuous glucose monitor (CGM) data, and A1C. Methods: Retrospective study among 1788 patients with diabetes from Kaiser Permanente Northern California (KPNC) who used CGM devices during 2016 to 2021. In this study population, there were 5264 A1C results; mean glucose was calculated from 124,388,901 CGM readings captured during the 90 days before each A1C result. Hierarchical mixed models were specified to estimate racial/ethnic differences in the association between mean glucose and A1C. Results: Mean A1C was 0.33 (95% confidence interval: 0.23-0.44; P < 0.0001) percentage points higher among African American patients relative to White patients for a given mean glucose. A1C results for Asians, Latinos, and multiethnic patients were not significantly different from those of White patients. The slope of the association between mean glucose and A1C did not differ significantly across racial/ethnic groups. Variance for the association between mean glucose and A1C was substantially greater within groups than between racial/ethnic groups (65% vs. 9%, respectively). Conclusions: For African American patients, A1C results may overestimate glycemia and could lead to premature diabetes diagnoses, overtreatment, or invalid assessments of health disparities. However, most of the variability in the mean glucose-A1C association was within racial/ethnic groups. Treatment decisions driven by guideline-based A1C targets should be individualized and supported by direct measurement of glycemia.

Severe hypoglycemia and falls in older adults with diabetes: The Diabetes & Aging Study

Objective

To estimate rates of severe hypoglycemia and falls among older adults with diabetes and evaluate their association.

Research Design and Methods

Survey in an age-stratified, random sample adults with diabetes age 65-100 years; respondents were asked about severe hypoglycemia (requiring assistance) and falls in the past 12 months. Prevalence ratios (adjusted for age, sex, race/ethnicity) estimated the increased risk of falls associated with severe hypoglycemia.

Results

Among 2,158 survey respondents, 79 (3.7%) reported severe hypoglycemia, of whom 68 (86.1%) had no ED visit or hospitalization for hypoglycemia. Falls were reported by 847 (39.2%), of whom 745 (88.0%) had no fall documented in outpatient or inpatient records. Severe hypoglycemia was associated with a 70% greater prevalence of falls (adjusted prevalence ratio = 1.7 (95% CI, 1.3-2.2)).

Conclusion

While clinical documentation of events likely reflects severity or care-seeking behavior, severe hypoglycemia and falls are common, under-reported life-threatening events.

Development and Validation of the Life Expectancy Estimator for Older Adults with Diabetes (LEAD): the Diabetes and Aging Study

BACKGROUND

Estimated life expectancy for older patients with diabetes informs decisions about treatment goals, cancer screening, long-term and advanced care, and inclusion in clinical trials. Easily implementable, evidence-based, diabetes-specific approaches for identifying patients with limited life expectancy are needed.

OBJECTIVE

Develop and validate an electronic health record (EHR)-based tool to identify older adults with diabetes who have limited life expectancy.

DESIGN

Predictive modeling based on survival analysis using Cox-Gompertz models in a retrospective cohort.

PARTICIPANTS

Adults with diabetes aged ≥ 65 years from Kaiser Permanente Northern California: a 2015 cohort (N = 121,396) with follow-up through 12/31/2019, randomly split into training (N = 97,085) and test (N = 24,311) sets. Validation was conducted in the test set and two temporally distinct cohorts: a 2010 cohort (n = 89,563; 10-year follow-up through 2019) and a 2019 cohort (n = 152,357; 2-year follow-up through 2020).

MAIN MEASURES

Demographics, diagnoses, utilization and procedures, medications, behaviors and vital signs; mortality.

KEY RESULTS

In the training set (mean age 75 years; 49% women; 48% racial and ethnic minorities), 23% died during 5 years follow-up. A mortality prediction model was developed using 94 candidate variables, distilled into a life expectancy model with 11 input variables, and transformed into a risk-scoring tool, the Life Expectancy Estimator for Older Adults with Diabetes (LEAD). LEAD discriminated well in the test set (C-statistic = 0.78), 2010 cohort (C-statistic = 0.74), and 2019 cohort (C-statistic = 0.81); comparisons of observed and predicted survival curves indicated good calibration.

CONCLUSIONS

LEAD estimates life expectancy in older adults with diabetes based on only 11 patient characteristics widely available in most EHRs and claims data. LEAD is simple and has potential application for shared decision-making, clinical trial inclusion, and resource allocation.

An electronic medical record (EMR) prompt improves screening rates for metabolic conditions among children with obesity

OBJECTIVE

This study evaluated the effectiveness of an automated prompt in the electronic medical record (EMR) to increase screening rates for metabolic conditions and referrals to health education and to improve BMI percentile among children with obesity.

METHODS

The intervention used an EMR reminder that provided a panel of lab orders (hemoglobin A1c, lipid panel, and alanine aminotransferase) during clinical encounters among pediatric patients ages 10 to 18 with BMI ≥ 95th percentile. Data on demographics, comorbid conditions, BMI, lab results, and health education referrals were analyzed. Cohorts during the year before (n = 3479) and after (n = 3439) workflow implementation were compared.

RESULTS

The distribution of race/ethnicity among children with obesity was 56% Hispanic, 19% White, 11% Filipino, 4% Pacific Islander, 3% Black, and 1% East/South Asian. Orders for metabolic lab tests increased from 2% in the pre-workflow period to 52% in the post-workflow period (p < 0.0001). Completed screening rates improved from 1% to 27% (p < 0.0001). Health education referrals increased from 0.4% to 7% (p < 0.0001). We observed a mean change in BMI percentile of -0.13% (p = 0.06).

CONCLUSIONS

This study validates the use of an EMR-based prompt to improve metabolic lab screening and health education referrals among children with obesity. During the limited period of follow-up, we found no significant change in BMI percentile.

Validation of a Hypoglycemia Risk Stratification Tool Using Data From Continuous Glucose Monitors

This cohort study uses data from continuous glucose monitoring to validate a hypoglycemia risk stratification tool.

Continuous Glucose Monitor Use Prevents Glycemic Deterioration in Insulin-Treated Patients with Type 2 Diabetes

Continuous glucose monitoring (CGM) is indicated in poorly controlled insulin-treated patients with type 2 diabetes (T2D) to improve glycemic control and reduce the risk of hypoglycemia, but the benefits of CGM for lower risk patients have not been well studied. Among 17,422 insulin-treated patients with T2D with hemoglobin A1c (HbA1c) <8% and no recent severe hypoglycemia (based on emergency room visits or hospitalizations), CGM initiation occurred in 149 patients (17,273 noninitiators served as reference). Changes in HbA1c and severe hypoglycemia rates for the 12 months before and after CGM initiation were calculated. CGM initiation was associated with decreased HbA1c (-0.06%), whereas noninitiation was associated with increased HbA1c (+0.32%); a weighted adjusted difference-in-difference model of change in HbA1c yielded a net benefit of -0.30%; 95% CI -0.50%, -0.10%; P = 0.004). No significant differences were observed for severe hypoglycemia. CGM may be useful in preventing glycemic deterioration in well-controlled patients with insulin-treated T2D.

Association of Real-time Continuous Glucose Monitoring With Glycemic Control and Acute Metabolic Events Among Patients With Insulin-Treated Diabetes

IMPORTANCE

Continuous glucose monitoring (CGM) is recommended for patients with type 1 diabetes; observational evidence for CGM in patients with insulin-treated type 2 diabetes is lacking.

OBJECTIVE

To estimate clinical outcomes of real-time CGM initiation.

DESIGN, SETTING, AND PARTICIPANTS

Exploratory retrospective cohort study of changes in outcomes associated with real-time CGM initiation, estimated using a difference-in-differences analysis. A total of 41 753 participants with insulin-treated diabetes (5673 type 1; 36 080 type 2) receiving care from a Northern California integrated health care delivery system (2014-2019), being treated with insulin, self-monitoring their blood glucose levels, and having no prior CGM use were included.

EXPOSURES

Initiation vs noninitiation of real-time CGM (reference group).

MAIN OUTCOMES AND MEASURES

Ten end points measured during the 12 months before and 12 months after baseline: hemoglobin A1c (HbA1c); hypoglycemia (emergency department or hospital utilization); hyperglycemia (emergency department or hospital utilization); HbA1c levels lower than 7%, lower than 8%, and higher than 9%; 1 emergency department encounter or more for any reason; 1 hospitalization or more for any reason; and number of outpatient visits and telephone visits.

RESULTS

The real-time CGM initiators included 3806 patients (mean age, 42.4 years [SD, 19.9 years]; 51% female; 91% type 1, 9% type 2); the noninitiators included 37 947 patients (mean age, 63.4 years [SD, 13.4 years]; 49% female; 6% type 1, 94% type 2). The prebaseline mean HbA1c was lower among real-time CGM initiators than among noninitiators, but real-time CGM initiators had higher prebaseline rates of hypoglycemia and hyperglycemia. Mean HbA1c declined among real-time CGM initiators from 8.17% to 7.76% and from 8.28% to 8.19% among noninitiators (adjusted difference-in-differences estimate, -0.40%; 95% CI, -0.48% to -0.32%; P < .001). Hypoglycemia rates declined among real-time CGM initiators from 5.1% to 3.0% and increased among noninitiators from 1.9% to 2.3% (difference-in-differences estimate, -2.7%; 95% CI, -4.4% to -1.1%; P = .001). There were also statistically significant differences in the adjusted net changes in the proportion of patients with HbA1c lower than 7% (adjusted difference-in-differences estimate, 9.6%; 95% CI, 7.1% to 12.2%; P < .001), lower than 8% (adjusted difference-in-differences estimate, 13.1%; 95% CI, 10.2% to 16.1%; P < .001), and higher than 9% (adjusted difference-in-differences estimate, -7.1%; 95% CI, -9.5% to -4.6%; P < .001) and in the number of outpatient visits (adjusted difference-in-differences estimate, -0.4; 95% CI, -0.6 to -0.2; P < .001) and telephone visits (adjusted difference-in-differences estimate, 1.1; 95% CI, 0.8 to 1.4; P < .001). Initiation of real-time CGM was not associated with statistically significant changes in rates of hyperglycemia, emergency department visits for any reason, or hospitalizations for any reason.

CONCLUSIONS AND RELEVANCE

In this retrospective cohort study, insulin-treated patients with diabetes selected by physicians for real-time continuous glucose monitoring compared with noninitiators had significant improvements in hemoglobin A1c and reductions in emergency department visits and hospitalizations for hypoglycemia, but no significant change in emergency department visits or hospitalizations for hyperglycemia or for any reason. Because of the observational study design, findings may have been susceptible to selection bias.

A catalog of associations between rare coding variants and COVID-19 outcomes

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) causes coronavirus disease-19 (COVID-19), a respiratory illness that can result in hospitalization or death. We investigated associations between rare genetic variants and seven COVID-19 outcomes in 543,213 individuals, including 8,248 with COVID-19. After accounting for multiple testing, we did not identify any clear associations with rare variants either exome-wide or when specifically focusing on (i) 14 interferon pathway genes in which rare deleterious variants have been reported in severe COVID-19 patients; (ii) 167 genes located in COVID-19 GWAS risk loci; or (iii) 32 additional genes of immunologic relevance and/or therapeutic potential. Our analyses indicate there are no significant associations with rare protein-coding variants with detectable effect sizes at our current sample sizes. Analyses will be updated as additional data become available, with results publicly browsable at https://rgc-covid19.regeneron.com.

Clinical Response to Real-Time Patient-Reported Diabetic Peripheral Neuropathy Symptoms

INTRODUCTION

To assess clinician response to real-time patient-reported data about diabetic peripheral neuropathy (DPN) symptoms, we analyzed DPN diagnosis and treatment patterns after administration of a 4-question symptom questionnaire in a large vertically integrated health care system.

METHODS

Retrospective cohort study to analyze data from 160,852 patients screened for DPN symptoms from April 2012 to March 2014. Electronic medical record data were used to study changes in DPN diagnosis, treatment initiation, and treatment intensification. We used logistic regression to study the association of patient characteristics with the odds of clinical response.

RESULTS

Of patients queried, 50,684 (31.5%) reported symptoms. Patients reporting DPN symptoms experienced a greater increase in new DPN diagnoses (16 percentage points; p < 0.0001) and medication use (4 percentage points; p < 0.0001) compared with those denying symptoms. Among patients reporting symptoms, women and nonwhite patients were less likely to receive a DPN diagnosis, whereas older patients were more likely to receive a DPN diagnosis. Overall, patients who were older, were Asian (hazard ratio = 0.67, 95% confidence interval = 0.63-0.77), and had lower socioeconomic status (hazard ratio = 0.89, 95% confidence interval = 0.80-0.99) were less likely to be treated. However, these racial and socioeconomic differences were not statistically significant for patients with preexisting DPN diagnoses.

CONCLUSION

Patients' real-time reports of DPN symptoms were associated with increased clinical activity. Patient- and clinician-level factors associated with the likelihood of receiving a DPN diagnosis need further study because a formal diagnosis may be associated with more equitable treatment.

Association of Initiation of Basal Insulin Analogs vs Neutral Protamine Hagedorn Insulin With Hypoglycemia-Related Emergency Department Visits or Hospital Admissions and With Glycemic Control in Patients With Type 2 Diabetes

IMPORTANCE

In clinical trials of patients with type 2 diabetes, long-acting insulin analogs modestly reduced the risk of nocturnal hypoglycemia compared with human neutral protamine Hagedorn (NPH) insulin, but cost 2 to 10 times more. Outcomes in clinical practice may differ from trial results.

OBJECTIVE

To compare the rates of hypoglycemia-related emergency department (ED) visits or hospital admissions associated with initiation of long-acting insulin analogs vs human NPH insulin in patients with type 2 diabetes.

DESIGN, SETTING, AND PARTICIPANTS

A retrospective observational study using data from Kaiser Permanente of Northern California from January 1, 2006, through September 30, 2015. Patients with type 2 diabetes who initiated a long-acting insulin analog or NPH insulin were included and censored at death, loss of health plan coverage, change in insulin treatment, or study end on September 30, 2015.

EXPOSURE

Initiation of basal insulin analogs (glargine or detemir) vs NPH insulin.

MAIN OUTCOMES AND MEASURES

The primary outcome was the time to a hypoglycemia-related ED visit or hospital admission and the secondary outcome was the change in hemoglobin A1c level within 1 year of insulin initiation.

RESULTS

There were 25 489 patients with type 2 diabetes who initiated basal insulin therapy (mean age, 60.2 [SD, 11.8] years; 51.9% white; 46.8% female). During a mean follow-up of 1.7 years, there were 39 hypoglycemia-related ED visits or hospital admissions among 1928 patients who initiated insulin analogs (11.9 events [95% CI, 8.1 to 15.6] per 1000 person-years) compared with 354 hypoglycemia-related ED visits or hospital admissions among 23 561 patients who initiated NPH insulin (8.8 events [95% CI, 7.9 to 9.8] per 1000 person-years) (between-group difference, 3.1 events [95% CI, -1.5 to 7.7] per 1000 person-years; P = .07). Among 4428 patients matched by propensity score, the adjusted hazard ratio was 1.16 (95% CI, 0.71 to 1.78) for hypoglycemia-related ED visits or hospital admissions associated with insulin analog use. Within 1 year of insulin initiation, hemoglobin A1c level decreased from 9.4% (95% CI, 9.3% to 9.5%) to 8.2% (95% CI, 8.1% to 8.2%) after initiation of insulin analogs and from 9.4% (95% CI, 9.3% to 9.5%) to 7.9% (95% CI, 7.9% to 8.0%) after initiation of NPH insulin (adjusted difference-in-differences for glycemic control, -0.22% [95% CI, -0.09% to -0.37%]).

CONCLUSIONS AND RELEVANCE

Among patients with type 2 diabetes, initiation of a basal insulin analog compared with NPH insulin was not associated with a reduced risk of hypoglycemia-related ED visits or hospital admissions or with improved glycemic control. These findings suggest that the use of basal insulin analogs in usual practice settings may not be associated with clinical advantages for these outcomes.

Correction to: Comparative Analysis of the Expression of Glutathione Peroxidase and Glutathione Reductase Genes in Human Sperm after Cryopreservation

The second author's name should read A. Yu. Romanov.

Effect of Out-of-Pocket Cost on Medication Initiation, Adherence, and Persistence among Patients with Type 2 Diabetes: The Diabetes Study of Northern California (DISTANCE)

OBJECTIVE

To estimate the effect of out-of-pocket (OOP) cost on nonadherence to classes of cardiometabolic medications among patients with diabetes.

DATA SOURCES/SETTING

Electronic health records from a large, health care delivery system for 223,730 patients with diabetes prescribed 842,899 new cardiometabolic medications during 2006-2012.

STUDY DESIGN

Observational, new prescription cohort study of the effect of OOP cost on medication initiation and adherence.

DATA COLLECTION

Adherence and OOP costs were based on pharmacy dispensing records and benefits.

PRINCIPAL FINDINGS

Primary nonadherence (never dispensed) increased monotonically with OOP cost after adjusting for demographics, neighborhood socioeconomic status, Medicare, medical financial assistance, OOP maximum, deductibles, mail order pharmacy incentive and use, drug type, generic or brand, day's supply, and comorbidity index; 7 percent were never dispensed the new medication when OOP cost ≥$11, 5 percent with OOP cost of $1-$10, and 3 percent when the medication was free of charge (p < .0001). Higher OOP cost was also strongly associated with inadequate secondary adherence (≥20 percent of time without adequate medication). There was no clinically significant or consistent relationship between OOP costs and early nonpersistence (dispensed once, never refilled) or later stage nonpersistence (discontinued within 24 months).

CONCLUSIONS

Cost-sharing may deter clinically vulnerable patients from initiating essential medications, undermining adherence and risk factor control.

Association of Patient-Physician Language Concordance and Glycemic Control for Limited-English Proficiency Latinos With Type 2 Diabetes

IMPORTANCE

Providing culturally competent care to the growing number of limited-English proficiency (LEP) Latinos with diabetes in the United States is challenging.

OBJECTIVE

To evaluate changes in risk factor control among LEP Latinos with diabetes who switched from language-discordant (English-only) primary care physicians (PCPs) to language-concordant (Spanish-speaking) PCPs or vice versa.

DESIGN, SETTING, AND PARTICIPANTS

This pre-post, difference-in-differences study selected 1605 adult patients with diabetes who self-identified as Latino, whose preferred language was Spanish, and who switched PCPs between January 1, 2007, and December 31, 2013. Study participants were members of the Kaiser Permanente Northern California health care system (an integrated health care delivery system with access to bilingual PCPs and/or professional interpreter services). Spanish-speaking and English-only PCPs were identified by self-report or utilization data.

EXPOSURES

Change in patient-PCP language concordance after switching PCPs.

MAIN OUTCOMES AND MEASURES

Glycemic control (glycated hemoglobin [HbA1c] < 8%), poor glycemic control (HbA1c > 9%), low-density-lipoprotein (LDL) control (LDL < 100 mg/dL), and systolic blood pressure (SBP) control (SBP < 140 mm Hg).

RESULTS

Overall, 1605 LEP Latino adults with diabetes (mean [SD] age, 60.5 [13.1] years) were included in this study, and there was a significant net improvement in glycemic and LDL control among patients who switched from language-discordant PCPs to concordant PCPs relative to those who switched from one discordant PCP to another discordant PCP. After adjustment and accounting for secular trends, the prevalence of glycemic control increased by 10% (95% CI, 2% to 17%; P = .01), poor glycemic control decreased by 4% (95% CI, -10% to 2%; P = .16) and LDL control increased by 9% (95% CI, 1% to 17%; P = .03). No significant changes were observed in SBP control. Prevalence of LDL control increased 15% (95% CI, 7% to 24%; P < .001) among LEP Latinos who switched from concordant to discordant PCPs. Risk factor control did not worsen following a PCP switch in any group.

CONCLUSIONS AND RELEVANCE

We observed significant improvements in glycemic control among LEP Latino patients with diabetes who switched from language-discordant to concordant PCPs. Facilitating language-concordant care may be a strategy for diabetes management among LEP Latinos.

Adherence to Newly Prescribed Diabetes Medications Among Insured Latino and White Patients With Diabetes

Importance

Medication adherence is essential to diabetes care. Patient-physician language barriers may affect medication adherence among Latino individuals.

Objective

To determine the association of patient race/ethnicity, preferred language, and physician language concordance with patient adherence to newly prescribed diabetes medications.

Design, Setting, and Participants

This observational study was conducted from January 1, 2006, to December 31, 2012, at a large integrated health care delivery system with professional interpreter services. Insured patients with type 2 diabetes, including English-speaking white, English-speaking Latino, or limited English proficiency (LEP) Latino patients with newly prescribed diabetes medication.

Exposures

Patient race/ethnicity, preferred language, and physician self-reported Spanish-language fluency.

Main Outcomes and Measures

Primary nonadherence (never dispensed), early-stage nonpersistence (dispensed only once), late-stage nonpersistence (received ≥2 dispensings, but discontinued within 24 months), and inadequate overall medication adherence (>20% time without sufficient medication supply during 24 months after initial prescription).

Results

Participants included 21 878 white patients, 5755 English-speaking Latino patients, and 3205 LEP Latino patients with a total of 46 131 prescriptions for new diabetes medications. Among LEP Latino patients, 50.2% (n = 1610) had a primary care physician reporting high Spanish fluency. For oral medications, early adherence varied substantially: 1032 LEP Latino patients (32.2%), 1565 English-speaking Latino patients (27.2%), and 4004 white patients (18.3%) were either primary nonadherent or early nonpersistent. Inadequate overall adherence was observed in 1929 LEP Latino patients (60.2%), 2975 English-speaking Latino patients (51.7%), and 8204 white patients (37.5%). For insulin, early-stage nonpersistence was 42.8% among LEP Latino patients (n = 1372), 34.4% among English-speaking Latino patients (n = 1980), and 28.5% among white patients (n = 6235). After adjustment for patient and physician characteristics, LEP Latino patients were more likely to be nonadherent to oral medications and insulin than English-speaking Latino patients (relative risks from 1.11 [95% CI, 1.06-1.15] to 1.17 [95% CI, 1.02-1.34]; P < .05) or white patients (relative risks from 1.36 [95% CI, 1.31-1.41] to 1.49 [95% CI, 1.32-1.69]; P < .05). English-speaking Latino patients were more likely to be nonadherent compared with white patients (relative risks from 1.23 [95% CI, 1.19-1.27] to 1.30 [95% CI, 1.23-1.39]; P < .05). Patient-physician language concordance was not associated with rates of nonadherence among LEP Latinos (relative risks from 0.92 [95% CI, 0.71-1.19] to 1.04 [95% CI, 0.97-1.1]; P > .28).

Conclusions and Relevance

Nonadherence to newly prescribed diabetes medications is substantially greater among Latino than white patients, even among English-speaking Latino patients. Limited English proficiency Latino patients are more likely to be nonadherent than English-speaking Latino patients independent of the Spanish-language fluency of their physicians. Interventions beyond access to interpreters or patient-physician language concordance will be required to improve medication adherence among Latino patients with diabetes.

Depressive symptoms and adherence to cardiometabolic therapies across phases of treatment among adults with diabetes: the Diabetes Study of Northern California (DISTANCE)

OBJECTIVE

Among adults with diabetes, depression is associated with poorer adherence to cardiometabolic medications in ongoing users; however, it is unknown whether this extends to early adherence among patients newly prescribed these medications. This study examined whether depressive symptoms among adults with diabetes newly prescribed cardiometabolic medications are associated with early and long-term nonadherence.

PATIENTS AND METHODS

An observational follow-up of 4,018 adults with type 2 diabetes who completed a survey in 2006 and were newly prescribed oral antihyperglycemic, antihypertensive, or lipid-lowering agents within the following year at Kaiser Permanente Northern California was conducted. Depressive symptoms were examined based on Patient Health Questionnaire-8 scores. Pharmacy utilization data were used to identify nonadherence by using validated methods: early nonadherence (medication never dispensed or dispensed once and never refilled) and long-term nonadherence (new prescription medication gap [NPMG]: percentage of time without medication supply). These analyses were conducted in 2016.

RESULTS

Patients with moderate-to-severe depressive symptoms had poorer adherence than nondepressed patients (8.3% more patients with early nonadherence, P=0.01; 4.9% patients with longer NPMG, P=0.002; 7.8% more patients with overall nonadherence [medication gap >20%], P=0.03). After adjustment for confounders, the models remained statistically significant for new NPMG (3.7% difference, P=0.02). There was a graded association between greater depression severity and nonadherence for all the models (test of trend, P<0.05).

CONCLUSION

Depressive symptoms were associated with modest differences in early and long-term adherence to newly prescribed cardiometabolic medications in diabetes patients. Interventions targeting adherence among adults with diabetes and depression need to address both initiation and maintenance of medication use.

Identifying Spanish Language Competent Physicians: The Diabetes Study of Northern California (DISTANCE)

OBJECTIVES

Language barriers negatively impact health care access and quality for US immigrants. Latinos are the second largest immigrant group and the largest, fastest growing minority. Health care systems need simple, low cost and accurate tools that they can use to identify physicians with Spanish language competence. We sought to address this need by validating a simple and low-cost tool already in use in a major health plan.

DESIGN SETTING PARTICIPANTS

A web-based survey conducted in 2012 among physicians caring for patients in a large, integrated health care delivery system. Of the 2,198 survey respondents, 111 were used in additional analysis involving patient report of those physicians' fluency.

MAIN OUTCOME MEASURES

We compared health care physicians' responses to a single item, Spanish language self-assessment tool (measuring "medical proficiency") with patient-reported physician language competence, and two validated physician self-assessment tools (measuring "fluency" and "confidence").

RESULTS

Concordance between medical proficiency was moderate with patient reports (weighted Kappa .45), substantial with fluency (weighted Kappa .76), and moderate-to-substantial with confidence (weighted Kappas .53 to .66).

CONCLUSIONS

The single-question self-reported medical proficiency tool is a low-cost tool useful for quickly identifying Spanish competent physicians and is potentially suitable for use in clinical settings. A reasonable approach for health systems is to designate only those physicians who self-assess their Spanish medical proficiency as "high" as competent to provide care without an interpreter.

Communication Barriers and the Clinical Recognition of Diabetic Peripheral Neuropathy in a Diverse Cohort of Adults: The DISTANCE Study

The purpose of this study was to explore communication barriers as independent predictors and potential mediators of variation in clinical recognition of diabetic peripheral neuropathy (DPN). In this cross-sectional analysis, we estimated the likelihood of having a DPN diagnosis among 4,436 patients with DPN symptoms. We controlled for symptom frequency, demographic and clinical characteristics, and visit frequency using a modified Poisson regression model. We then evaluated 4 communication barriers as independent predictors of clinical documentation and as possible mediators of racial/ethnic differences: difficulty speaking English, not talking to one's doctor about pain, limited health literacy, and reports of suboptimal patient-provider communication. Difficulty speaking English and not talking with one's doctor about pain were independently associated with not having a diagnosis, though limited health literacy and suboptimal patient-provider communication were not. Limited English proficiency partially attenuated, but did not fully explain, racial/ethnic differences in clinical documentation among Chinese, Latino, and Filipino patients. Providers should be encouraged to talk with their patients about DPN symptoms, and health systems should consider enhancing strategies to improve timely clinical recognition of DPN among patients who have difficult speaking English. More work is needed to understand persistent racial/ethnic differences in diagnosis.

Financial Strain and Medication Adherence among Diabetes Patients in an Integrated Health Care Delivery System: The Diabetes Study of Northern California (DISTANCE)

OBJECTIVE

To examine self-reported financial strain in relation to pharmacy utilization adherence data.

DATA SOURCES/STUDY SETTING

Survey, administrative, and electronic medical data from Kaiser Permanente Northern California.

STUDY DESIGN

Retrospective cohort design (2006, n = 7,773).

DATA COLLECTION/EXTRACTION METHODS

We compared survey self-reports of general and medication-specific financial strain to three adherence outcomes from pharmacy records, specifying adjusted generalized linear regression models.

PRINCIPAL FINDINGS

Eight percent and 9 percent reported general and medication-specific financial strain. In adjusted models, general strain was significantly associated with primary nonadherence (RR = 1.37; 95 percent CI: 1.04-1.81) and refilling late (RR = 1.34; 95 percent CI: 1.07-1.66); and medication-specific strain was associated with primary nonadherence (RR = 1.42, 95 percent CI: 1.09-1.84).

CONCLUSIONS

Simple, minimally intrusive questions could be used to identify patients at risk of poor adherence due to financial barriers.

Reach and Validity of an Objective Medication Adherence Measure Among Safety Net Health Plan Members with Diabetes: A Cross-Sectional Study

BACKGROUND

With the expansion of Medicaid and low-cost health insurance plans among diverse patient populations, objective measures of medication adherence using pharmacy claims could advance clinical care and translational research for safety net care. However, safety net patients may experience fluctuating prescription drug coverage, affecting the performance of adherence measures.

OBJECTIVE

To evaluate the performance of continuous medication gap (CMG) for diverse, low-income managed care members with diabetes.

METHODS

We conducted this cross-sectional analysis using administrative and clinical data for 680 members eligible for a self-management support trial at a nonprofit, government-sponsored managed care plan. We applied CMG methodology to cardiometabolic medication claims for English- , Cantonese- , or Spanish-speaking members with diabetes. We examined inclusiveness (the proportion with calculable CMG) and selectivity (sociodemographic and medical differences from members without CMG). For validity, we examined unadjusted associations of suboptimal adherence (CMG >  20%) with suboptimal cardiometabolic control.

RESULTS

429 members (63%) had calculable CMG. Compared with members without CMG, members with CMG were younger, more likely employed, and had poorer glycemic control but had better blood pressure and lipid control. Suboptimal adherence occurred more frequently among members with poor cardiometabolic control than among members with optimal control (28% vs. 12%, P = 0.02).

CONCLUSIONS

CMG demonstrated acceptable inclusiveness and validity in a diverse, low-income safety net population, comparable with its performance in studies among other insured populations. CMG may provide a useful tool to measure adherence among increasingly diverse Medicaid populations, complemented by other strategies to reach those not captured by CMG.

An algorithm to identify medication nonpersistence using electronic pharmacy databases

OBJECTIVE

Identifying patients who are medication nonpersistent (fail to refill in a timely manner) is important for healthcare operations and research. However, consistent methods to detect nonpersistence using electronic pharmacy records are presently lacking. We developed and validated a nonpersistence algorithm for chronically used medications.

MATERIALS AND METHODS

Refill patterns of adult diabetes patients (n = 14,349) prescribed cardiometabolic therapies were studied. We evaluated various grace periods (30-300 days) to identify medication nonpersistence, which is defined as a gap between refills that exceeds a threshold equal to the last days' supply dispensed plus a grace period plus days of stockpiled medication. Since data on medication stockpiles are typically unavailable for ongoing users, we compared nonpersistence to rates calculated using algorithms that ignored stockpiles.

RESULTS

When using grace periods equal to or greater than the number of days' supply dispensed (i.e., at least 100 days), this novel algorithm for medication nonpersistence gave consistent results whether or not it accounted for days of stockpiled medication. The agreement (Kappa coefficients) between nonpersistence rates using algorithms with versus without stockpiling improved with longer grace periods and ranged from 0.63 (for 30 days) to 0.98 (for a 300-day grace period).

CONCLUSIONS

Our method has utility for health care operations and research in prevalent (ongoing) and new user cohorts. The algorithm detects a subset of patients with inadequate medication-taking behavior not identified as primary nonadherent or secondary nonadherent. Healthcare systems can most comprehensively identify patients with short- or long-term medication underutilization by identifying primary nonadherence, secondary nonadherence, and nonpersistence.

Ethnic Differences in Geriatric Conditions and Diabetes Complications Among Older, Insured Adults With Diabetes: The Diabetes and Aging Study

OBJECTIVE

The aim of this study was to evaluate ethnic differences in burden of prevalent geriatric conditions and diabetic complications among older, insured adults with diabetes.

METHOD

An observational study was conducted among 115,538 diabetes patients, aged ≥60, in an integrated health care system with uniform access to care.

RESULTS

Compared with Whites, Asians and Filipinos were more likely to be underweight but had substantively lower prevalence of falls, urinary incontinence, polypharmacy, depression, and chronic pain, and were least likely of all groups to have at least one geriatric condition. African Americans had significantly lower prevalence of incontinence and falls, but higher prevalence of dementia; Latinos had a lower prevalence of falls. Except for end-stage renal disease (ESRD), Whites tended to have the highest rates of prevalent diabetic complications.

DISCUSSION

Among these insured older adults, ethnic health patterns varied substantially; differences were frequently small and rates were often better among select minority groups, suggesting progress toward the Healthy People 2020 objective to reduce health disparities.

Incidence of remission in adults with type 2 diabetes: the diabetes & aging study

OBJECTIVE

To estimate the incidence of remission in adults with type 2 diabetes not treated with bariatric surgery and to identify variables associated with remission.

RESEARCH DESIGN AND METHODS

We quantified the incidence of diabetes remission and examined its correlates among 122,781 adults with type 2 diabetes in an integrated healthcare delivery system. Remission required the absence of ongoing drug therapy and was defined as follows: 1) partial: at least 1 year of subdiabetic hyperglycemia (hemoglobin A1c [HbA₁c] level 5.7-6.4% [39-46 mmol/mol]); 2) complete: at least 1 year of normoglycemia (HbA₁c level <5.7% [<39 mmol/mol]); and 3) prolonged: complete remission for at least 5 years.

RESULTS

The incidence density (remissions per 1,000 person-years; 95% CI) of partial, complete, or prolonged remission was 2.8 (2.6-2.9), 0.24 (0.20-0.28), and 0.04 (0.01-0.06), respectively. The 7-year cumulative incidence of partial, complete, or prolonged remission was 1.47% (1.40-1.54%), 0.14% (0.12-0.16%), and 0.007% (0.003-0.020%), respectively. The 7-year cumulative incidence of achieving any remission was 1.60% in the whole cohort (1.53-1.68%) and 4.6% in the subgroup with new-onset diabetes (<2 years since diagnosis) (4.3-4.9%). After adjusting for demographic and clinical characteristics, correlates of remission included age >65 years, African American race, <2 years since diagnosis, baseline HbA₁c level <5.7% (<39 mmol/mol), and no diabetes medication at baseline.

CONCLUSIONS

In community settings, remission of type 2 diabetes does occur without bariatric surgery, but it is very rare.

Impact of a pharmacy benefit change on new use of mail order pharmacy among diabetes patients: the Diabetes Study of Northern California (DISTANCE)

OBJECTIVE

To assess the impact of a pharmacy benefit change on mail order pharmacy (MOP) uptake.

DATA SOURCES/STUDY SETTING

Race-stratified, random sample of diabetes patients in an integrated health care delivery system.

STUDY DESIGN

In this natural experiment, we studied the impact of a pharmacy benefit change that conditionally discounted medications if patients used MOP and prepaid two copayments. We compared MOP uptake among those exposed to the benefit change (n = 2,442) and the reference group with no benefit change (n = 8,148), and estimated differential MOP uptake across social strata using a difference-in-differences framework.

DATA COLLECTION/EXTRACTION METHODS

Ascertained MOP uptake (initiation among previous nonusers).

PRINCIPAL FINDINGS

Thirty percent of patients started using MOP after receiving the benefit change versus 9 percent uptake among the reference group (p < .0001). After adjustment, there was a 26 percentage point greater MOP uptake (benefit change effect). This benefit change effect was significantly smaller among patients with inadequate health literacy (15 percent less), limited English proficiency (14 percent less), and among Latinos and Asians (24 and 16 percent less compared to Caucasians).

CONCLUSIONS

Conditionally discounting medications delivered by MOP effectively stimulated MOP uptake overall, but it unintentionally widened previously existing social gaps in MOP use because it stimulated less MOP uptake in vulnerable populations.

Associations between antidepressant adherence and shared decision-making, patient-provider trust, and communication among adults with diabetes: diabetes study of Northern California (DISTANCE)

BACKGROUND

Depression and adherence to antidepressant treatment are important clinical concerns in diabetes care. While patient-provider communication patterns have been associated with adherence for cardiometabolic medications, it is unknown whether interpersonal aspects of care impact antidepressant medication adherence.

OBJECTIVE

To determine whether shared decision-making, patient-provider trust, or communication are associated with early stage and ongoing antidepressant adherence.

DESIGN

Observational new prescription cohort study.

SETTING

Kaiser Permanente Northern California.

PATIENTS

One thousand five hundred twenty-three adults with type 2 diabetes who completed a survey in 2006 and received a new antidepressant prescription during 2006-2010.

MEASUREMENTS

Exposures included items based on the Trust in Physicians and Interpersonal Processes of Care instruments and the Consumer Assessment of Healthcare Providers and Systems (CAHPS) communication scale. Measures of adherence were estimated using validated methods with physician prescribing and pharmacy dispensing data: primary non-adherence (medication never dispensed), early non-persistence (dispensed once, never refilled), and new prescription medication gap (NPMG; proportion of time without medication during 12 months after initial prescription).

RESULTS

After adjusting for potential confounders, patients' perceived lack of shared decision-making was significantly associated with primary non-adherence (RR = 2.42, p < 0.05), early non-persistence (RR = 1.34, p < 0.01) and NPMG (estimated 5% greater gap in medication supply, p < 0.01). Less trust in provider was significantly associated with early non-persistence (RRs 1.22-1.25, ps < 0.05) and NPMG (estimated NPMG differences 5-8%, ps < 0.01).

LIMITATIONS

All patients were insured and had consistent access to and quality of care.

CONCLUSIONS

Patients' perceptions of their relationships with providers, including lack of shared decision-making or trust, demonstrated strong associations with antidepressant non-adherence. Further research should explore whether interventions for healthcare providers and systems that foster shared decision-making and trust might also improve medication adherence.

Health literacy and antidepressant medication adherence among adults with diabetes: the diabetes study of Northern California (DISTANCE)

BACKGROUND

Previous studies have reported that health literacy limitations are associated with poorer disease control for chronic conditions, but have not evaluated potential associations with medication adherence.

OBJECTIVE

To determine whether health literacy limitations are associated with poorer antidepressant medication adherence.

DESIGN

Observational new prescription cohort follow-up study.

PARTICIPANTS

Adults with type 2 diabetes who completed a survey in 2006 and received a new antidepressant prescription during 2006-2010 (N = 1,366) at Kaiser Permanente Northern California.

MAIN MEASURES

Validated three-item self-report scale measured health literacy. Discrete indices of adherence based on pharmacy dispensing data according to validated methods: primary non-adherence (medication never dispensed); early non-persistence (dispensed once, never refilled); non-persistence at 180 and 365 days; and new prescription medication gap (NPMG; proportion of time that the person is without medication during 12 months after the prescription date).

KEY RESULTS

Seventy-two percent of patients were classified as having health literacy limitations. After adjusting for sociodemographic and clinical covariates, patients with health literacy limitations had significantly poorer adherence compared to patients with no limitations, whether measured as early non-persistence (46 % versus 38 %, p < 0.05), non-persistence at 180 days (55 % versus 46 %, p < 0.05), or NPMG (41 % versus 36%, p < 0.01). There were no significant associations with primary adherence or non-persistence at 365 days.

CONCLUSIONS

Poorer antidepressant adherence among adults with diabetes and health literacy limitations may jeopardize the continuation and maintenance phases of depression pharmacotherapy. Findings underscore the importance of national efforts to address health literacy, simplify health communications regarding treatment options, improve public understanding of depression treatment, and monitor antidepressant adherence.

Association between estimated GFR, health-related quality of life, and depression among older adults with diabetes: the Diabetes and Aging Study

BACKGROUND

Although chronic kidney disease (CKD) is a highly prevalent condition among older adults with diabetes, the associations between health-related quality of life (HRQoL) and severity of CKD in this population are not well understood. The objective of this study was to assess HRQoL and depressive symptoms across estimated glomerular filtration rate (eGFR) stages.

STUDY DESIGN

Cross-sectional.

SETTING & PARTICIPANTS

5,805 members of Kaiser Permanente Northern California, 60 years or older with diabetes, from the 2005-2006 Diabetes Study of Northern California (DISTANCE) survey.

PREDICTOR

eGFR categories were defined as ≥90 (referent category), 75-89, 60-74, 45-59, 30-44, or ≤29 mL/min/1.73 m(2).

OUTCOMES

HRQoL was measured using the modified Short Form-8 Physical Component Summary (PCS) and Mental Component Summary (MCS) scores. Depressive symptoms were measured using the Patient Health Questionnaire-8.

RESULTS

In unadjusted linear regression analyses, physical (PCS) and mental (MCS) HRQoL scores were significantly lower with worsening eGFR level. However, after adjustment for sociodemographics, diabetes duration, obesity, and cardiovascular comorbid conditions and taking into account interactions with proteinuria, none of the eGFR categories was significantly or substantively associated with PCS or MCS score. In both unadjusted and adjusted analyses, higher risk of depressive symptoms was observed in respondents with eGFR ≤29 mL/min/1.73 m(2) (relative risk, 2.02; 95% CI, 1.10-3.71; P < 0.05) compared with the referent group. However, this eGFR-depression relationship was no longer significant after adjusting for hemoglobin level.

LIMITATIONS

Participants are part of a single health care delivery system.

CONCLUSIONS

Our findings suggest the need for greater attention to and potential interventions for depression in patients with reduced eGFR.

Confirming genes influencing risk to cleft lip with/without cleft palate in a case-parent trio study

A collection of 1,108 case-parent trios ascertained through an isolated, nonsyndromic cleft lip with or without cleft palate (CL/P) was used to replicate the findings from a genome-wide association study (GWAS) conducted by Beaty et al. (Nat Genet 42:525-529, 2010), where four different genes/regions were identified as influencing risk to CL/P. Tagging SNPs for 33 different genes were genotyped (1,269 SNPs). All four of the genes originally identified as showing genome-wide significance (IRF6, ABCA4 and MAF, plus the 8q24 region) were confirmed in this independent sample of trios (who were primarily of European and Southeast Asian ancestry). In addition, eight genes classified as 'second tier' hits in the original study (PAX7, THADA, COL8A1/FILIP1L, DCAF4L2, GADD45G, NTN1, RBFOX3 and FOXE1) showed evidence of linkage and association in this replication sample. Meta-analysis between the original GWAS trios and these replication trios showed PAX7, COL8A1/FILIP1L and NTN1 achieved genome-wide significance. Tests for gene-environment interaction between these 33 genes and maternal smoking found evidence for interaction with two additional genes: GRID2 and ELAVL2 among European mothers (who had a higher rate of smoking than Asian mothers). Formal tests for gene-gene interaction (epistasis) failed to show evidence of statistical interaction in any simple fashion. This study confirms that many different genes influence risk to CL/P.

Communication and medication refill adherence: the Diabetes Study of Northern California

BACKGROUND

Poor medication refill adherence contributes to poor cardiometabolic control and diabetes outcomes. Studies linking communication between patients and health care providers to adherence often use self-reported adherence and have not explored differences across communication domains or therapeutic indications.

METHODS

To investigate associations between patient communication ratings and cardiometabolic medication refill adherence, we conducted a cross-sectional analysis of 9377 patients in the Diabetes Study of Northern California (DISTANCE), a race-stratified, random sample of Kaiser Permanente survey respondents. Eligible participants received 1 or more oral hypoglycemic, lipid-lowering, or antihypertensive medication in the 12 months preceding the survey. Communication was measured with a 4-item Consumer Assessment of Healthcare Providers and Systems Survey (CAHPS) score and 4 items from the Trust in Physicians and Interpersonal Processes of Care instruments. Poor adherence was classified as greater than a 20% continuous medication gap for ongoing medication therapies. Using modified least squares regression, we calculated differences in poor adherence prevalence for a 10-point decrease in CAHPS score and compared higher vs lower communication ratings on other items, adjusting for necessary sociodemographic and medical confounders derived from a directed acyclic graph.

RESULTS

In this cohort, 30% had poor cardiometabolic medication refill adherence. For each 10-point decrease in CAHPS score, the adjusted prevalence of poor adherence increased by 0.9% (P=.01). Compared with patients offering higher ratings, patients who gave health care providers lower ratings for involving patients in decisions, understanding patients' problems with treatment, and eliciting confidence and trust were more likely to have poor adherence, with absolute differences of 4% (P=.04), 5% (P=.02), and 6% (P=.03), respectively. Associations between communication and adherence were somewhat larger for hypoglycemic medications than for other medications.

CONCLUSIONS

Poor communication ratings were independently associated with objectively measured inadequate cardiometabolic medication refill adherence, particularly for oral hypoglycemic medications. Future studies should investigate whether improving communication skills among clinicians with poorer patient communication ratings could improve their patients' cardiometabolic medication refill adherence and outcomes.

Association of depression with increased risk of dementia in patients with type 2 diabetes: the Diabetes and Aging Study

CONTEXT

Although depression is a risk factor for dementia in the general population, its association with dementia among patients with diabetes mellitus has not been well studied.

OBJECTIVE

To determine whether comorbid depression in patients with type 2 diabetes increases the risk of development of dementia.

DESIGN

The Diabetes and Aging Study was a cohort investigation that surveyed a racially/ethnically stratified random sample of patients with type 2 diabetes.

SETTING

A large, integrated, nonprofit managed care setting in Northern California.

PARTICIPANTS

A sample of 19,239 diabetes registry members 30 to 75 years of age.

MAIN OUTCOME MEASURES

The Patient Health Questionnaire 8, International Classification of Diseases, Ninth Revision (ICD-9) diagnoses of depression, and/or antidepressant prescriptions in the 12 months prior to baseline were used to identify prevalent cases of depression. Clinically recognized dementia was identified among subjects with no prior ICD-9 Clinical Modification (ICD-9-CM) diagnoses of dementia. To exclude the possibility that depression was a prodrome of dementia, dementia diagnoses were only based on ICD-9-CM diagnoses identified in years 3 to 5 postbaseline. The risk of dementia for patients with depression and diabetes relative to patients with diabetes alone was estimated using Cox proportional hazard regression models that adjusted for sociodemographic, clinical, and health risk factors and health use.

RESULTS

During the 3- to 5-year period, 80 of 3766 patients (2.1%) with comorbid depression and diabetes (incidence rate of 5.5 per 1000 person-years) vs 158 of 15,473 patients (1.0%) with diabetes alone (incidence rate of 2.6 per 1000 person-years) had 1 or more ICD-9-CM diagnoses of dementia. Patients with comorbid depression had a 100% increased risk of dementia during the 3 to 5 years postbaseline (adjusted hazard ratio, 2.02; 95% confidence interval, 1.73-2.35).

CONCLUSION

Depression in patients with diabetes was associated with a substantively increased risk for development of dementia compared with those with diabetes alone.

Ethnic differences in appointment-keeping and implications for the patient-centered medical home--findings from the Diabetes Study of Northern California (DISTANCE)

OBJECTIVE

To examine ethnic differences in appointment-keeping in a managed care setting.

DATA SOURCES/STUDY SETTING

Kaiser Permanente Diabetes Study of Northern California (DISTANCE), 2005-2007, n = 12,957.

STUDY DESIGN

Cohort study. Poor appointment-keeping (PAK) was defined as missing >1/3 of planned, primary care appointments. Poisson regression models were used to estimate ethnic-specific relative risks of PAK (adjusting for demographic, socio-economic, health status, and facility effects).

DATA COLLECTION/EXTRACTION METHODS

Administrative/electronic health records and survey responses.

PRINCIPAL FINDINGS

Poor appointment-keeping rates differed >2-fold across ethnicities: Latinos (12 percent), African Americans (10 percent), Filipinos (7 percent), Caucasians (6 percent), and Asians (5 percent), but also varied by medical center. Receiving >50 percent of outpatient care via same-day appointments was associated with a 4-fold greater PAK rate. PAK was associated with 20, 30, and 40 percent increased risk of elevated HbA1c (>7 percent), low-density lipoprotein (>100 mm/dl), and systolic blood pressure (>130 mmHg), respectively.

CONCLUSIONS

Latinos and African Americans were at highest risk of missing planned primary care appointments. PAK was associated with a greater reliance on same-day visits and substantively poorer clinical outcomes. These results have important implications for public health and health plan policy, as primary care rapidly expands toward open access to care supported by the patient-centered medical home model.

Adherence to laboratory test requests by patients with diabetes: the Diabetes Study of Northern California (DISTANCE)

OBJECTIVES

To estimate rates and predictors of clinical laboratory test completion by patients with diabetes after provider referral.

STUDY DESIGN

Prospective cohort study.

METHODS

Among 186,306 adult members with diabetes in Kaiser Permanente Northern California, we searched the electronic medical records (July 1, 2008, to June 30, 2009) of each patient for the first outpatient order to obtain the following laboratory tests commonly used to measure risk factor control or adverse effects of pharmacotherapy: levels of glycosylated hemoglobin, low density lipoprotein cholesterol, serum creatinine, urinary albumin, or creatine kinase (the latter only among persons using statins). We measured laboratory test attendance as completion of an order (including time to results) within 6 months of the referral date and looked for variations by subgroups.

RESULTS

Laboratory test attendance ranged from 86% for glycosylated hemoglobin level to 73% for serum creatinine level. Time to laboratory test attendance was a median of 7 to 11 days and a mean of 25 to 30 days. Laboratory test attendance was more likely for women and older patients or for orders after a face-to-face provider visit and was less likely for orders by a pharmacist. However, most variations (even by laboratory copayment) were small or not clinically substantive. In subanalyses, we observed no clinically significant variations by race/ethnicity, socioeconomic status, trust in provider, or patient-provider communication and found no association with depressive symptoms, health literacy, or English fluency.

CONCLUSION

The fact that 1 in 7 patients did not complete laboratory tests within 6 months of the provider referral may help explain why healthcare services seem to fall short of optimal diabetes care.

Barriers to insulin initiation: the translating research into action for diabetes insulin starts project

OBJECTIVE

Reasons for failing to initiate prescribed insulin (primary nonadherence) are poorly understood. We investigated barriers to insulin initiation following a new prescription.

RESEARCH DESIGN AND METHODS

We surveyed insulin-naïve patients with poorly controlled type 2 diabetes, already treated with two or more oral agents who were recently prescribed insulin. We compared responses for respondents prescribed, but never initiating, insulin (n = 69) with those dispensed insulin (n = 100).

RESULTS

Subjects failing to initiate prescribed insulin commonly reported misconceptions regarding insulin risk (35% believed that insulin causes blindness, renal failure, amputations, heart attacks, strokes, or early death), plans to instead work harder on behavioral goals, sense of personal failure, low self-efficacy, injection phobia, hypoglycemia concerns, negative impact on social life and job, inadequate health literacy, health care provider inadequately explaining risks/benefits, and limited insulin self-management training.

CONCLUSIONS

Primary adherence for insulin may be improved through better provider communication regarding risks, shared decision making, and insulin self-management training.

Ethnic differences in anemia among patients with diabetes mellitus: the Diabetes Study of Northern California (DISTANCE)

To examine ethnic differences in hemoglobin testing practices and to test the hypothesis that ethnicity is an independent predictor of anemia among patients with diabetes mellitus. We conducted a panel study to assess the rate of hemoglobin testing during 1999-2001 and the period prevalence and incidence of anemia among 79,985 adults with diabetes mellitus receiving care within Kaiser Permanente of Northern California. Anemia was defined as hemoglobin <13.0 g/dL in men or < 12.0 g/dL in women. Overall, 82.1% of the cohort was tested for anemia at least once during the 3-year study period. Mixed ethnicity patients were most likely to be tested, followed by whites, blacks, Latinos, and Asians (P < 0.0001). Fifteen percent of the cohort had prevalent anemia at baseline, and an additional 22% of those tested developed anemia during the study period. Anemia was more prevalent among blacks and mixed ethnicity persons compared with other racial/ethnic groups. Anemia was also more prevalent among those >/=70 years of age or with estimated glomerular filtration rate <60 ml/min/1.73 m(2). In multivariable models, blacks had higher and Asians had lower odds of prevalent anemia and hazard ratios of incident anemia compared with whites. Within a large, diverse cohort with diabetes, ethnicity was predictive of anemia, even after adjustment for age, level of kidney function, and other potential confounders. Blacks with diabetes are at increased risk of anemia relative to whites. These differences may account for some of the observed ethnic disparities in diabetes complications.

Mail-order pharmacy use and adherence to diabetes-related medications

OBJECTIVE

To investigate whether patients who use mail-order pharmacies were more likely to have good medication adherence than patients who use local pharmacies.

STUDY DESIGN

Cross-sectional investigation.

METHODS

We conducted cross-sectional analyses of patients from the Kaiser Permanente Northern California (KPNC) diabetes registry who received a new antiglycemic, antihypertensive, or lipid-lowering index medication between January 1, 2006, and May 31, 2006. We defined good adherence as medication availability at least 80% of the time (ie, a continuous measure of medication gaps value of < or = 20%) and compared adherence between mail-order users (> or = 66% of refills by mail) and KPNC local pharmacy users (all refills in person). Adherence was calculated from the initial dispensing through 15 months of follow-up, medication discontinuation, or May 31, 2007, whichever came first. We analyzed the data using multivariate logistic regression models, after determining that unmeasured patient-level factors and self-selection did not significantly bias our analyses.

RESULTS

A total of 13,922 eligible patients refilled an index medication. Compared with those who used only local KPNC pharmacies, patients who received medications by mail were more likely to have good adherence (84.7% vs 76.9%, P <.001). After adjusting for potential confounders, including days' supply and out-of-pocket costs, mailorder users had better adherence to antiglycemic, antihypertensive, and lipid-lowering medications (P <.001 for all).

CONCLUSIONS

Compared with patients who obtained medication refills at local pharmacies, patients who received them by mail were more likely to have good adherence. The association between mail-order use and medication adherence should be evaluated in a randomized clinical trial.

New prescription medication gaps: a comprehensive measure of adherence to new prescriptions

OBJECTIVE

Describe a novel approach to comprehensively summarize medication adherence.

DATA SOURCES/STUDY SETTING

Kaiser Permanente Northern California Diabetes Registry (n approximately 220,000)

STUDY DESIGN

In a new prescription cohort design (27,329 subjects prescribed new medications), we used pharmacy utilization data to estimate adherence during 24 months follow-up. Proportion of time without sufficient medications (medication gaps) was estimated using a novel measure (New Prescription Medication Gaps [NPMG]) and compared with a traditional measure of adherence.

DATA COLLECTION/EXTRACTION METHODS

Data derived from electronic medical records and survey responses.

PRINCIPAL FINDINGS

Twenty-two percent of patients did not become ongoing users (had zero or only one dispensing of the new prescription). The proportion of newly prescribed patients that never became ongoing users was eightfold greater than the proportion who maintained ongoing use, but with inadequate adherence. Four percent of those with at least two dispensings discontinued therapy during the 24 months follow-up. NPMG was significantly associated with high out-of-pocket costs, self-reported adherence, and clinical response to therapy.

CONCLUSIONS

NPMG is a valid adherence measure. Findings also suggest a larger burden of inadequate adherence than previously thought. Public health efforts have traditionally focused on improving adherence in ongoing users; clearly more attention is needed to address nonpersistence in the very first stages after a new medication is prescribed.

Glycemic response to newly initiated diabetes therapies

OBJECTIVE

The glycemic response to antihyperglycemic therapies for type 2 diabetes has been thoroughly evaluated in randomized controlled trials, but inadequately studied in real-world settings.

STUDY DESIGN

We studied glycemic response among 15 126 type 2 diabetic patients who initiated any single new antihyperglycemic agent (metformin, sulfonylureas, thiazolidinediones, or insulin added to medical nutrition therapy or to existing diabetes therapies) during 1999-2000 within Kaiser Permanente of Northern California, an integrated healthcare delivery system.

METHODS

Pre-post (3-12 months after initiation) change in glycosylated hemoglobin (A1C) was analyzed using ANCOVA (analysis of covariance) models adjusted for baseline A1C, concurrent (ongoing) antihyperglycemic therapy, demographics, health behaviors, medication adherence, clinical factors, and processes of care.

RESULTS

Mean A1C was 9.01% (95% confidence interval [CI] 8.98%-9.04%) before therapy initiation and 7.87% (95% CI 7.85%-7.90%) 3 to 12 months after initiation (mean A1C reduction 1.14 percentage points; 95% CI 1.11-1.17). Overall, 30.2% (95% CI 29.2%-31.1%) of patients achieved glycemic target (A1C < 7%). Although baseline disease severity and concurrent therapies differed greatly across therapeutic classes, after adjustment for these baseline clinical characteristics, no significant differences were noted in glucose-lowering effect across therapeutic classes. Treatment effects did not differ by age, race, diabetes duration, obesity, or level of renal function.

CONCLUSIONS

Metformin, sulfonylures, thiazolidinediones, and insulin were equally effective in improving glucose control. Nonetheless, most patients failed to achieve the glycemic target. Findings suggest that, to keep up with progressive worsening of glycemic control, patients and providers must commit to earlier, more aggressive therapy intensification, triggered promptly after A1C exceeds the recommended glycemic target.

Effect of cost-sharing changes on self-monitoring of blood glucose

OBJECTIVE

To study the effect of cost-sharing policy changes on utilization of test strips for self-monitoring of blood glucose.

STUDY DESIGN

A legislative mandate (January 1, 2000) required California health plans to cover diabetes supplies, including those for self-monitoring of blood glucose. One health plan, Kaiser Permanente Northern California, initially waived established copayments and provided free test strips to members with diabetes mellitus for 2 years but later instituted a 20% coinsurance charge for a portion of their membership.

METHODS

A retrospective cohort design was used to study pharmacy-based estimates of test strip utilization changes during this natural experiment. Analyses included 2 cohort investigations using pretest-posttest analysis with control subjects to study transitions from a copayment period to a free test strip period and from the free test strip period to a coinsurance period.

RESULTS

During the copayment period, test strip utilization was inversely related to copayments for test strips. Offering free test strips did not increase utilization, even among those paying higher copayments before the policy change. Price-elastic patterns formed before and during the copayment period persisted, despite receiving free test strips for 2 years. The coinsurance, introduced after 2 years of receiving free test strips, resulted in statistically significant (but not clinically relevant) decreased utilization (approximately 1-3 fewer test strips/month). Change patterns did not differ by socioeconomic status.

CONCLUSIONS

Offering free test strips shifted costs from patient to health plan, without improving adherence. The introduced coinsurance slightly reduced utilization and adherence to recommendations about self-monitoring of blood glucose. Neither intervention had marked clinical effect. Cross-sectional analyses should not be used to predict utilization changes in the face of rapidly evolving benefit policies.

Longitudinal study of new and prevalent use of self-monitoring of blood glucose

OBJECTIVE

We sought to assess longitudinal association between self-monitoring of blood glucose (SMBG) and glycemic control in diabetic patients from an integrated health plan (Kaiser Permanente Northern California).

RESEARCH DESIGN AND METHODS

Longitudinal analyses of glycemic control among 1) 16,091 patients initiating SMBG (new-user cohort) and 2) 15,347 ongoing users of SMBG (prevalent-user cohort). SMBG frequency was based on pharmacy use (number of blood glucose test strips dispensed), and glycemic control was based on HbA(1c) (A1C). In the new-user cohort, ANCOVA models (pre- and posttest design) were used to assess the effect of initiating SMBG. In the prevalent-user cohort, repeated-measure, mixed-effects models with random-intercept and time-dependent covariates were used to assess changes in SMBG and A1C. All models were stratified by therapy (no medications, oral agents only, or insulin) and adjusted for baseline A1C, sociodemographics, insulin injection frequency, comorbidity index, medication adherence, smoking status, health care use, and provider specialty.

RESULTS

Greater SMBG practice frequency among new users was associated with a graded decrease in A1C (relative to nonusers) regardless of diabetes therapy (P < 0.0001). Changes in SMBG frequency among prevalent users were associated with an inverse graded change in A1C only among pharmacologically treated patients (P < 0.0001).

CONCLUSIONS

These observational findings are consistent with short-term benefits of initiating SMBG practice for all patients but continuing benefits only for pharmacologically treated patients. Differences in effectiveness between new versus prevalent users of SMBG have implications for guideline development and interpretation of observational outcomes data.

Pioglitazone initiation and subsequent hospitalization for congestive heart failure

AIMS

Thiazolidinediones (TZD) have been associated with an expansion in plasma volume and the development of peripheral oedema. A recent study reported an association between the use of TZDs and development of congestive heart failure (CHF). The objective of this study was to determine if short-term use of pioglitazone, a TZD, is associated with increased risk of admission to hospital because of CHF in a well-characterized, community-based cohort of Type 2 diabetic patients without prevalent CHF.

METHODS

A cohort study of all patients in the Kaiser Permanente Medical Care Program with Type 2 diabetes (Kaiser Permanente Northern California Diabetes Registry) who initiated any diabetes pharmacotherapy (n = 23 440) between October 1999 and November 2001. Only patients initiating single new therapies ('new users') were included to reduce confounding and create mutually exclusive exposure groups. We constructed Cox proportional hazards models (with sulphonylureas initiators specified as the reference group) to evaluate the impact of initiating new diabetes therapies on time-to-incident admission to hospital because of CHF, defined by primary hospital discharge diagnosis.

RESULTS

Patients initiated pioglitazone (15.2%), sulphonylureas (25.3%), metformin (50.9%), and insulin (8.6%) alone, or as additions to pre-existing or maintained therapies. Three hundred and twenty admissions for CHF were observed during the follow-up (mean 10.2 months) after drug initiation. Relative to patients initiating sulphonylureas, there were no significant increases in the incidence of hospitalization for CHF in those initiating pioglitazone [hazard ratio (HR) = 1.28; 95% confidence interval (CI): 0.85-1.92] after adjusting for demographic, behavioural and clinical factors. There was a significantly higher incidence among those initiating insulin (HR = 1.56; 95% CI: 1.00-2.45) and lower incidence among those initiating metformin (HR = 0.70; 95% CI: 0.49-0.99).

CONCLUSIONS

This study of patients with Type 2 diabetes failed to find evidence that short-term pioglitazone use was associated with an elevated risk of hospitalization for CHF relative to the standard, first-line diabetes therapy.

Achieving good glycemic control: initiation of new antihyperglycemic therapies in patients with type 2 diabetes from the Kaiser Permanente Northern California Diabetes Registry

OBJECTIVE

To compare the effectiveness of antihyperglycemic therapies in type 2 diabetic patients with poor glycemic control (baseline glycosylated hemoglobin [HbA1C] > 8%).

STUDY DESIGN

Longitudinal (cohort) study.

METHODS

Study patients were 4775 type 2 diabetic patients who initiated new antihyperglycemic therapies and maintained them for up to 1 year. The study setting was Kaiser Permanente Northern California Medical Group, an integrated, prepaid, healthcare delivery organization. Treatment regimens were 1 or more of the following: insulin, thiazolidinediones, sulfonylureas, biguanides (metformin), or other less frequently used options (including meglitinides or alpha-glucosidase inhibitors).

RESULTS

In this cohort, the mean HbA1C was 9.9% when therapy was initiated. Within 1 year, there was a drop of 1.3 percentage points in the mean HbA1C (to 8.6%), and 18% of new initiators achieved HbA1C values of < or = 7%. After adjusting for baseline clinical differences, the proportion of patients treated to goal was greatest among those receiving thiazolidinediones in combination (24.6%-25.7%) or a regimen of metformin and insulin (24.9%), while the least success was experienced by those receiving sulfonylureas alone (12.5%) or insulin-sulfonylureas regimens (10.9%). The probability of achieving the target goal was most strongly predicted by the level of glycemic control before initiation, but patient behaviors (eg, frequent self-monitoring, lower rates of missed appointments) also were strongly associated with greater levels of control.

CONCLUSION

Overall, therapy initiation resulted in an impressive population-level benefit. However, since most new initiators still had not achieved good control within 12 months, careful monitoring and prompt therapy intensification remain important.

Missed Appointments and Poor Glycemic Control

OBJECTIVE

When patients miss scheduled medical appointments, continuity and effectiveness of healthcare delivery is reduced, appropriate monitoring of health status lapses, and the cost of health services increases. We evaluated the relationship between missed appointments and glycemic control (glycosylated hemoglobin or HbA1c) in a large, managed care population of diabetic patients.

RESEARCH DESIGN AND METHODS

Missed appointment rate was related cross-sectionally to glycemic control among 84,040 members of the Kaiser Permanente Northern California Diabetes Registry during 2000. Adjusted least-square mean estimates of HbA1c were derived by level of appointment keeping (none missed, 1-30% missed, and >30% missed appointments for the calendar year) stratified by diabetes therapy.

RESULTS

Twelve percent of the subjects missed more than 30% of scheduled appointments during 2000. Greater rates of missed appointments were associated with significantly poorer glycemic control after adjusting for demographic factors (age, sex), clinical status, and health care utilization. The adjusted mean HbA1c among members who missed >30% of scheduled appointments was 0.70 to 0.79 points higher (P <0.0001) relative to those attending all appointments. Patients who missed more than 30% of their appointments were less likely to practice daily self-monitoring of blood glucose and to have poor oral medication refill adherence.

CONCLUSION

Patients who underuse care lack recorded information needed to determine level of risk. Frequently missed appointments were associated with poorer glycemic control and suboptimal diabetes self-management practice, are readily ascertained in clinical settings, and therefore could have clinical utility as a risk-stratifying criterion indicating the need for targeted case management.

Intron homing with limited exon homology. Illegitimate double-strand-break repair in intron acquisition by phage t4

The td intron of bacteriophage T4 encodes a DNA endonuclease that initiates intron homing to cognate intronless alleles by a double-strand-break (DSB) repair process. A genetic assay was developed to analyze the relationship between exon homology and homing efficiency. Because models predict exonucleolytic processing of the cleaved recipient leading to homologous strand invasion of the donor allele, the assay was performed in wild-type and exonuclease-deficient (rnh or dexA) phage. Efficient homing was supported by exon lengths of 50 bp or greater, whereas more limited exon lengths led to a precipitous decline in homing levels. However, extensive homology in one exon still supported elevated homing levels when the other exon was completely absent. Analysis of these "one-sided" events revealed recombination junctions at ectopic sites of microhomology and implicated nucleolytic degradation in illegitimate DSB repair in T4. Interestingly, homing efficiency with extremely limiting exon homology was greatly elevated in phage deficient in the 3'-5' exonuclease, DexA, suggesting that the length of 3' tails is a major determinant of the efficiency of DSB repair. Together, these results suggest that illegitimate DSB repair may provide a means by which introns can invade ectopic sites.

Role of exonucleolytic degradation in group I intron homing in phage T4

Homing of the phage T4 td intron is initiated by the intron-encoded endonuclease I-TevI, which cleaves the intronless allele 23 and 25 nucleotides upstream of the intron insertion site (IS). The distance between the I-TevI cleavage site (CS) and IS implicates endo- and/or exonuclease activities to resect the DNA segment between the IS and CS. Furthermore, 3' tails must presumably be generated for strand invasion by 5'-3' exonuclease activity. Three experimental approaches were used to probe for phage nucleases involved in homing: a comparative analysis of in vivo homing levels of nuclease-deficient phage, an in vitro assay of nuclease activity and specificity, and a coconversion analysis of flanking exon markers. It was thereby demonstrated that T4 RNase H, a 5'-3' exonuclease, T4 DNA exonuclease A (DexA) and the exonuclease activity of T4 DNA polymerase (43Exo), 3'-5' exonucleases, play a role in intron homing. The absence of these functions impacts not only homing efficiency but also the extent of degradation and flanking marker coconversion. These results underscore the critical importance of the 3' tail in intron homing, and they provide the first direct evidence of a role for 3' single-stranded DNA ends as intermediates in T4 recombination. Also, the involvement of RNase H, DexA, and 43Exo in homing provides a clear example of the harnessing of functions variously involved in phage nucleic acid metabolism for intron propagation.