Comparative effectiveness of early versus delayed metformin in the treatment of type 2 diabetes

Comparing the Effect of Early Versus Delayed Metformin Treatment on Glycaemic Parameters Among Australian Adults With Incident Diabetes: Evidence Using a National General Practice Database

PURPOSE

To compare the effect of early vs delayed metformin treatment for glycaemic management among patients with incident diabetes.

METHODS

Cohort study using electronic health records of regular patients (1+ visits per year in 3 consecutive years) aged 40+ years with 'incident' diabetes attending Australian general practices (MedicineInsight, 2011-2018). Patients with incident diabetes were defined as those who had a) 12+ months of medical data before the first recording of a diabetes diagnosis AND b) a diagnosis of 'diabetes' recorded at least twice in their electronic medical records or a diagnosis of 'diabetes' recorded only once combined with at least 1 abnormal glycaemic result (i.e., HbA1c ≥6.5%, fasting blood glucose [FBG] ≥7.0 mmol/L, or oral glucose tolerance test ≥11.1mmol/L) in the preceding 3 months. The effect of early (<3 months), timely (3-6 months), or delayed (6-12 months) initiation of metformin treatment vs no metformin treatment within 12 months of diagnosis on HbA1c and FBG levels 3 to 24 months after diagnosis was compared using linear regression and augmented inverse probability weighted models. Patients initially managed with other antidiabetic medications (alone or combined with metformin) were excluded.

FINDINGS

Of 18,856 patients with incident diabetes, 38.8% were prescribed metformin within 3 months, 3.9% between 3 and 6 months, and 6.2% between 6 and 12 months after diagnosis. The untreated group had the lowest baseline parameters (mean HbA1c 6.4%; FBG 6.9mmol/L) and maintained steady levels throughout follow-up. Baseline glycaemic parameters for those on early treatment with metformin (<3 months since diagnosis) were the highest among all groups (mean HbA1c 7.6%; FBG 8.8mmol/L), reaching controlled levels at 3 to 6 months (mean HbA1c 6.5%; FBG 6.9mmol/L) with sustained improvement until the end of follow-up (mean HbA1c 6.4%; FBG 6.9mmol/L at 18-24 months). Patients with timely and delayed treatment also improved their glycaemic parameters after initiating treatment (timely treatment: mean HbA1c 7.3% and FBG 8.3mmol/L at 3-6 months; 6.6% and 6.9mmol/L at 6-12 months; delayed treatment: mean HbA1c 7.2% and FBG 8.4mmol/L at 6-12 months; 6.7% and 7.1mmol/L at 12-18 months). Compared to those not managed with metformin, the corresponding average treatment effect for HbA1c at 18-24 months was +0.04% (95%CI -0.05;0.10) for early, +0.24% (95%CI 0.11;0.37) for timely, and +0.29% (95%CI 0.20;0.39) for delayed treatment.

IMPLICATIONS

Early metformin therapy (<3 months) for patients recently diagnosed with diabetes consistently improved HbA1c and FBG levels in the first 24 months of diagnosis.

Early treatment with dipeptidyl-peptidase 4 inhibitors reduces glycaemic variability and delays insulin initiation in type 2 diabetes: A propensity score-matched cohort study

AIMS

To examine whether early treatment intensification using dipeptidyl-peptidase 4 inhibitors (DPP4i) delays insulin initiation in Chinese patients diagnosed with type 2 diabetes for less than 5 years.

MATERIALS AND METHODS

In a territory-wide prospective cohort study, patients with type 2 diabetes initiating DPP4i at diabetes duration <2 years (early intensification) and 3-5 years (late intensification) were matched using 1:1 propensity-score matching (n = 908 in each arm). We used Cox regression to compare the risk of insulin initiation between the two groups. We explored the interactive and mediation effects of glycated haemoglobin (HbA1c) variability score (HVS), defined as the percentage of HbA1c varying by ≥0.5% compared with preceding values.

RESULTS

Of 1816 patients (60.7% men, mean age 54.4 ± 11.9 years), 92.4% and 71.9% were treated with metformin and sulphonylureas respectively at DPP4i initiation. Early DPP4i intensification [hazard ratio (HR) 0.71, (95% CI 0.58-0.68)] and low HVS (<50%) (HR = 0.40, 0.33-0.50) were associated with delayed insulin initiation during a median 4.08 years of follow-up. Early intensification with low HVS had the lowest risk versus late intensification with high HVS (HR = 0.30, 0.22-0.40) (pinteraction  = 0.013). HVS mediated 19.5% of the total effect of early DPP4i intensification on delaying insulin initiation. The late and early intensification groups had similar HbA1c at month 0 (8.4 ± 1.3% vs. 8.4 ± 1.5%) and month 3 (7.6 ± 1.2% vs. 7.6 ± 1.3%) after DPP4i initiation. By month 12, HbA1c in the late intensification group deteriorated (7.9 ± 1.4%) but remained stable in the early intensification group (7.6 ± 1.4%, p = 0.001) with persistent between-group difference over 72 months (8.2 ± 1.7% vs. 7.7 ± 1.6%, p = 0.001).

CONCLUSIONS

In type 2 diabetes, early DPP4i intensification delayed insulin initiation, partially explained by reduced glycaemic variability.

The substantial burden of non-communicable diseases and HIV-comorbidity amongst adults: Screening results from an integrated HIV testing services clinic for adults in Soweto, South Africa

BACKGROUND

South Africa is disproportionately impacted by non-communicable diseases (NCDs) and HIV/AIDS. We investigated the prevalence of known/unknown NCD risk factors, HIV, and NCD risk factor-HIV comorbidity; and treatment status on known diseases to determine the prevalence of controlled/uncontrolled disease.

METHODS

This cross-sectional study (June 2018-March 2019) within an integrated testing centre in Soweto, South Africa, screened adults (aged ≥18 years) for body mass index (BMI), hypertension (HT), rapid glucose and cholesterol, and HIV. Results were stratified by age group, sex, HIV-status, and self-reported ART use. Analysis included Fisher's exact, chi-squared, Kruskal Wallis, and Student's T-tests.

FINDINGS

Of 780 enrolled participants, 19.2% were HIV-positive, 37.5% were overweight/obese, 18.0% hypertensive, 10.8% hyperglycaemic, and 8.1% had hypercholesterolaemia. Significantly more women had overweight/obese BMI than men (46.8% vs 19.7%; p<0.0001), and women aged 25-34 years had significantly more hypercholesterolaemia than same-aged men (18.2% vs 5.6%; p = 0.02). HIV-positive participants had significantly more hyperglycaemia than HIV-negative participants (16.1% vs 9.6%; p = 0.02), and those on ART (63.9%) had significantly more hypercholesterolaemia than those not on ART (21.7% vs. 4.9%; p = 0.002). Of participants with HT, hyperglycaemia, and hypercholesterolaemia; 72.4%, 96.1%, and 93.3% were newly diagnosed. All participants with previously diagnosed NCDs remained with uncontrolled disease.

INTERPRETATION

There is a high burden of HIV, NCD risk factors, and comorbidity in Soweto, and amongst young adults (18-34 years), especially women. Lowering age requirements for glucose/cholesterol screening to 18+ years, regardless of BMI, HIV-status, or ART use, may yield timely NCD diagnosis/management.

Risk of incident dementia following metformin initiation compared with noninitiation or delay of antidiabetic medication therapy

PURPOSE

Emerging evidence suggests metformin compared with sulfonylurea is associated with an 8% to 10% lower risk for dementia. Guidelines recommend metformin as initial diabetes treatment, but there is still the question of treatment timing. Thus, the risk of dementia associated with initiating metformin compared with not initiating or delaying treatment was examined.

METHODS

A retrospective cohort study (1996 to 2015) was conducted with electronic health records from Veteran Health Affairs (VHA; n = 112 845) and Kaiser Permanente Washington (KPW; n = 14 333) healthcare systems. Patients were aged ≥50 years, had a hemoglobin A1c (HbA1c) between 6.5 and <9.5 mg/dL, and did not have dementia or fills for antidiabetic medications before cohort entry. Initiators started metformin monotherapy and noninitiators used no antidiabetic medications in the 6 months after the first qualifying HbA1c. The primary outcome was incident dementia. Propensity scores and inverse probability of treatment weighting (IPTW) controlled for confounding in Cox proportional hazards models.

RESULTS

During a median follow-up of 6.2 years in VHA and 6.8 years in KPW, there were 7547 new dementia cases in VHA and 1090 in KPW. After IPTW, there was no association between initiation of metformin (vs no initial treatment) and incident dementia in VHA (HR = 1.04; 95% confidence interval [CI]: 0.95-1.13) or KPW (HR = 0.81; 95% CI: 0.51-1.28). Results did not differ by age, baseline HbA1c, or race.

CONCLUSIONS

Results do not support initiating metformin earlier to prevent cognitive decline and, thus, may dampen enthusiasm for metformin as a potential antidementia drug. Randomized clinical trials could help clarify the relationship between metformin and cognitive decline.

Delays in Insulin Initiation among Patients with Type 2 Diabetes Mellitus in Southeast China: A Retrospective, Real-World Study

PURPOSE

To describe the extent of delays in insulin initiation, analyze its impact on glycemic control, and explore factors influencing delayed insulin initiation among Chinese type 2 diabetes mellitus (T2DM) patients.

METHODS

A real-world, retrospective cohort study with regional electronic health records from Fuzhou, southeast China was conducted among T2DM patients. Adult patients uncontrolled with oral antidiabetic drugs (OADs; HbA_1c ≥7%) and initiated on insulin treatment were included. Time to insulin initiation was described. After propensity-score matching, Wilcoxon rank-sum test and chi-square test were used to compare follow-up HbA_1c (first HbA_1c 3 months after insulin initiation) between timely (initiated insulin within 6 months after OAD failure) and delayed (initiated after 6 months) insulin-initiation groups. Sensitivity analysis was also performed by linear and logistic regression. Factors associated with delayed insulin initiation were explored using logistic regression.

RESULTS

A total of 940 patients were included, with mean±SD age 66.3±11.9 years. In sum, 328 had HbA_1c recorded 3 months after insulin initiation. After propensity-score matching (1:1 matching), 184 patients were included for further analysis. Median follow-up HbA_1c was lower in the timely-initiation group than the delayed-initiation group (7.25% vs 8.25%, P=0.009). Patients in the timely initiation group also had higher odds of achieving HbA_1c <7% (OR=3.15, P=0.001). Results were confirmed by logistic regression. Hypertension, coronary artery disease, baseline HbA_1c, and hospital level at insulin initiation were associated with delays in insulin initiation.

CONCLUSION

Timely insulin initiation after OAD failure is associated with better glycemic control.

High prevalence and heterogeneity of Dysglycemia in patients with tuberculosis from Peru: a prospective cohort study

BACKGROUND

The accuracy of different laboratory tests for diagnosis of diabetes mellitus (DM) and prediabetes (preDM) in populations exposed to tuberculosis (TB) remains poorly understood. Here, we examined the prevalence of DM and preDM in TB affected people in Lima, Peru.

METHODS

A prospective cohort study of patients affected TB and their household contacts (HHC), was conducted between February and November 2017 in Lima, Peru. Fasting plasma glucose (FPG), HbA1c and oral glucose tolerance test (OGTT) were used to detect DM and preDM in a prospective cohort of TB patients (n = 136) and household contacts (n = 138). Diagnostic performance of the laboratory tests was analyzed. Potential effects of sociodemographic and clinical factors on detection of dysglycemia were analyzed.

RESULTS

In TB patients, prevalence of DM and preDM was 13.97 and 30.88% respectively. Lower prevalence of both DM (6.52%) and preDM (28.99%) were observed in contacts. FPG, HbA1c and OGTT had poor agreement in detection of preDM in either TB cases or contacts. TB-DM patients had substantially lower hemoglobin levels, which resulted in low accuracy of HbA1c-based diagnosis. Classic sociodemographic and clinical characteristics were not different between TB patients with or without dysglycemia.

CONCLUSION

High prevalence of DM and preDM was found in both TB patients and contacts in Lima. Anemia was strongly associated with TB-DM, which directly affected the diagnostic performance of HbA1c in such population.

Factors Associated with Diabetes-Related Clinical Inertia in a Managed Care Population and Its Effect on Hemoglobin A1c Goal Attainment: A Claims-Based Analysis

BACKGROUND

Despite evidence showing the benefits of treatment intensification following an elevated hemoglobin A1c (A1c), clinical inertia, or failure to establish and/or escalate treatment to achieve treatment goals, is a concern among patients diagnosed with type 2 diabetes (T2DM). Clinical inertia may contribute to increased health care utilization and costs due to poor clinical outcomes in MCOs.

OBJECTIVES

To (a) identify factors associated with clinical inertia in T2DM and (b) determine differences in A1c goal attainment between patients who experience clinical inertia versus treatment intensification in a commercially insured population.

METHODS

Medical and pharmacy claims data were used to identify commercially insured patients in a regional MCO with a recorded A1c ≥ 8.0% between January 1, 2013, and December 31, 2015. In the 4 months following the first elevated A1c value (index date), patients were classified into 2 groups: treatment intensification or clinical inertia. Treatment intensification was defined as the addition of ≥ 1 new noninsulin antihyperglycemic medication, the addition of insulin, or a dose increase of any current noninsulin antihyperglycemic medication. Patients were required to have ≥ 1 follow-up A1c value 6-12 months after the index date and continuous enrollment in the health plan for 12 months before and after the index date. Patients were excluded if they had a diagnosis for gestational diabetes or type 1 diabetes or if they were on insulin in the pre-index period. The primary outcome of attaining A1c < 7.0% was compared between groups after propensity score matching (PSM). Factors associated with clinical inertia were identified using logistic regression.

RESULTS

3,078 patients, with a mean (SD) age of 54.4 (10.6) years and a mean (SD) baseline A1c of 9.6% (1.7), were included in the study. Of these, 1,093 patients (36%) experienced clinical inertia. After PSM, 1,760 patients remained; 880 in each group. In the clinical inertia group, 23% of patients achieved an A1c < 7.0% in the post-index period, compared with 35% in the treatment intensification group (P < 0.001). A greater likelihood of experiencing clinical inertia was associated with baseline treatment with 2 (OR = 1.51, 95% CI = 1.22-2.86; P < 0.001) or ≥ 3 (OR = 1.78, 95% CI = 1.30-2.42; P < 0.001) antihyperglycemic medications (vs. none), baseline age ≥ 65 years (OR = 2.11, 95% CI = 1.63-2.74; P < 0.001), and diagnosis of coronary heart disease (OR = 1.44, 95% CI = 1.10-1.88; P = 0.007). A baseline A1c ≥ 9.0% (vs. 8.0%-8.9%) was associated with a lower likelihood of experiencing clinical inertia (OR = 0.56, 95% CI = 0.48-0.66; P < 0.001).

CONCLUSIONS

More than a third of patients in a commercially insured population with T2DM and a baseline A1c ≥ 8% experienced clinical inertia. Clinical inertia resulted in worse A1c outcomes over the 12-month follow-up period. Results of this study suggest that treatment intensification should be monitored, with efforts made to educate health care providers on strategies aimed at improving glycemic control for high-risk patients.

DISCLOSURES

This study was funded by a grant from Janssen Scientific Affairs, which was involved in study design, interpretation of results, and manuscript review. Wander reports consulting fees from Sanofi Aventis outside the submitted work. McAdam-Marx reports grants from Sanofi Aventis and AstraZeneca outside the submitted work. Pesa and Bailey were employees of Janssen Scientific Affairs during the conduct of the study. Bailey also reports stock ownership in Johnson and Johnson. This study was presented as a poster at the Academy of Managed Care Pharmacy Nexus 2017; October 16-19, 2017; Grapevine, TX.

Change in HbA1c associated with treatment intensification among patients with type 2 diabetes and poor glycemic control

OBJECTIVE

We conducted a retrospective cohort study to investigate the HbA1c change associated with treatment intensification in a real-world population of patients with type 2 diabetes (T2D).

METHODS

Using a large US insurance claims database, patients aged ≥18 years with a T2D diagnosis and HbA1c ≥8.0% (64 mmol/mol) after ≥3 months of oral pharmacotherapy with metformin (± other oral antidiabetes agents) were identified (index date). Continuous enrollment was required for ≥12 months before (baseline) and after the index date with no baseline use of injectable antidiabetes drugs. We defined treatment intensification as prescriptions for injectable or additional oral antidiabetes drugs. Time to intensification was classified as timely (within 6 months) or not (≥6 months or not intensified). Linear regression models with propensity score 1:1 matching were performed to assess the effect of timely intensification on HbA1c.

RESULTS

Of the 11,525 patients meeting the inclusion criteria, only 37% had treatment intensified within 6 months. Mean age at index date was 57 years, 40% of the sample was female. The mean baseline A1C was 9.4% and 9.0%, while post-index A1C was 7.9% and 8.2% for timely intensified patients versus not, respectively. Patients with timely intensification had significantly greater HbA1c reduction compared with others (-0.33%, 95% CI: -0.41% to -0.25%) within 1 year of follow up.

CONCLUSIONS

In this analysis of patients with T2D and treatment failure in a real-world setting, earlier treatment intensification was associated with better glycemic control as indicated by lower HbA1c values.

Gaps and barriers in the control of blood glucose in people with type 2 diabetes

BACKGROUND

Glycaemic control is suboptimal in a large proportion of people with type 2 diabetes who are consequently at an increased and avoidable risk of potentially severe complications. We sought to explore attitudes and practices among healthcare professionals that may contribute to suboptimal glycaemic control through a review of recent relevant publications in the scientific literature.

METHODS

An electronic search of the PubMed database was performed to identify relevant publications from January 2011 to July 2015. The electronic search was complemented by a manual search of abstracts from key diabetes conferences in 2014/2015 available online.

RESULTS

Recently published data indicate that glycaemic control is suboptimal in a substantial proportion (typically 40%-60%) of people with diabetes. This is the case across geographic regions and in both low- and higher-income countries. Therapeutic inertia appears to be an important contributor to poor glycaemic control in up to half of people with type 2 diabetes. In particular, prescribers are often willing to tolerate extended periods of 'mild' hyperglycaemia as well as having low expectations for their patients. There are often delays of 3 years or longer in initiating or intensifying glucose-lowering therapy when needed.

CONCLUSION

Many people with type 2 diabetes are failed by current management, with approximately half not achieving or maintaining appropriate target blood glucose levels, leaving these patients at increased and avoidable risk of serious complications. Review criteria: The methodology of this review article is detailed in the 'Methods' section.

Treatment intensification for patients with type 2 diabetes and poor glycaemic control

AIMS

To identify the time to and patient characteristics associated with treatment intensification in patients with type 2 diabetes (T2D) and poor glycaemic control.

METHODS

Using a large US insurance claims database, we conducted a retrospective cohort study among adult patients with T2D and glycated haemoglobin (HbA1c) ≥8% (index date) after ≥3 months of therapy including metformin. Patients were required to have continuous enrolment for at least 12 months before (baseline) and after index date, and no injectable antidiabetes medications. We defined treatment intensification as prescription fill for injectable or additional oral antidiabetic drugs (OADs). Cox modelling was performed to identify factors associated with time to treatment intensification.

RESULTS

For the 11 525 patients meeting the inclusion criteria, the mean age at index date was 57 years, 40% were female and the mean index HbA1c was 9.1%. Overall, 37% of patients had their treatment intensified <6 months after, 11% had their treatment intensified 6-12 months after, and 52% did not have their treatment intensified <12 months after the index date. A higher index HbA1c was associated with early intensification [hazard ratio (HR) 1.18 for HbA1c ≥9 to <10% and HR 1.41 for HbA1c ≥10% compared with HbA1c ≥8 to <9%; p < 0.0001), and later line of therapy was associated with late intensification (HR 0.78 for metformin with one OAD and HR 0.68 for metformin with ≥2 OADs compared with metformin monotherapy; p < 0.0001).

CONCLUSIONS

Fewer than half of patients with T2D and treatment failure received intensification within 12 months in a real-world US population. Factors associated with treatment inertia can be used to target clinical care for these patients.