Predictors of glycemic control among patients with Type 2 diabetes: a longitudinal study

Association between metformin use and risk of prostate cancer and its grade

BACKGROUND

Metformin is commonly prescribed to treat type 2 diabetes. Recent evidence suggests that it may possess antitumoral properties. The aim of this study was to test the association between metformin use and risk of prostate cancer and its grade among men with diabetes.

METHODS

Data were obtained from population-based health-care administrative databases in Ontario, Canada. This retrospective cohort study used a nested case-control approach to examine the relationship between metformin exposure and the risk of prostate cancer within a cohort of incident diabetic men aged 66 years or older. We conducted four case-control analyses, defining case subjects as 1) any prostate cancer, 2) high-grade, 3) low-grade, and 4) biopsy-diagnosed. In each analysis, case subjects were matched to five control subjects on age and cohort entry date. Metformin exposure was determined based on prescriptions before cancer diagnosis, and adjusted odds ratios (aOR) were estimated using conditional logistic regression. All statistical tests were two-sided.

RESULTS

Within our cohort of 119 315 men with diabetes, there were 5306 case subjects with prostate cancer and 26 530 matched control subjects. Within the cancer case subjects, 1104 had high- grade cancer, 1719 had low-grade cancer, and 3524 had biopsy-diagnosed cancer. There was no association between metformin use and risk of any prostate cancer (aOR = 1.03, 95% confidence interval [CI] = 0.96 to 1.1), high-grade cancer (aOR = 1.13, 95% CI = 0.96 to 1.32), low-grade cancer (aOR = 0.94, 95% CI = 0.82 to 1.06), or biopsy-diagnosed cancer (aOR = 0.98, 95% CI = 0.84 to 1.02).

CONCLUSIONS

This large study did not find an association between metformin use and risk of prostate cancer among older men with diabetes, regardless of cancer grade or method of diagnosis.

Characterization of factors affecting attainment of glycemic control in Asian Americans with diabetes in a culturally specific program

PURPOSE

The purpose of this study is to examine the effectiveness of a culturally specific pilot clinic for Asian Americans (AA) in reaching glycemic target and to characterize factors affecting the attainment of glycemic control in comparison with white counterparts.

METHODS

This electronic health record review included all new AA patients with type 2 diabetes (n = 109) in a culturally specific program and a randomly selected sample of new white patients with type 2 diabetes (n = 218) in the adult clinic within the same time period and diabetes center.

RESULTS

AA and whites had a comparable proportion of patients with A1C ≤7% (32.1%, 34.9%; P = .621) at baseline and after 12 months of care (48.6%, 56.0%; P = .210), with a similar A1C decline (-0.9% ± 1.6%, -0.8% ± 1.7%, P = .710) by 12 months. Factors associated with the lack of success in reaching target in AA but not in whites included older age, lower educational attainment, less likelihood of having health insurance, and a need for more educational visits. The percentage of AA reaching A1C ≤7%, as compared to whites, worsened among those with highest initial A1C when stratified by ascending quartiles (96.7% vs 85.2%, P = .101; 61.9% vs 58.9%, P = .813; 24.0% vs 37.7%, P = .230; 15.2% vs 35.4%, P = .044).

CONCLUSION

While a culturally specific diabetes program in a specialty setting achieved a similar glycemic outcome for AA compared with whites, reasons for not reaching glycemic target differed. The findings suggest that the elimination of diabetes disparities requires not only culturally and linguistically specific programs, but must also identify and address the socio-environmental differences unique to each population.

Younger adult type 2 diabetic patients have poorer glycaemic control: a cross-sectional study in a primary care setting in Singapore

BACKGROUND

The aim was to study the glycaemic control of type 2 diabetic patients, and to identify factors associated with unacceptable glycaemic control (defined as HbA1c >8.0%).

METHODS

Analysis of data collected in a cross-sectional survey of type 2 diabetic patients in eight SingHealth Polyclinics in January 2009. HbA1c value was measured on the day of the survey, while information on patient and diabetic characteristics was obtained through a questionnaire. Odds ratio of having unacceptable glycaemic control was estimated for selected variables using multiple logistic regression models.

RESULTS

A total of 688 patients were included in the analysis. The mean (± standard deviation) and median (range) HbA1c levels were 7.6% (± 1.35) and 7.3% (5.0% to 14.0%), respectively. 25.4% of the patients had an unacceptable HbA1c level of >8.0% and the odds of this were higher (p < 0.05) in patients with the following characteristics: younger age, longer diabetes duration, presence of insulin treatment, and poorer compliance to medication.

CONCLUSION

Younger adult patients were found to have poorer glycaemic control, and hence targeted educational and behaviour modification programmes would be required to effectively manage this group of patients.

Self-monitoring among non-insulin treated patients with type 2 diabetes mellitus: Patients' behavioural responses to readings and associations with glycaemic control

AIM

To investigate self-monitoring of blood glucose (SMBG) behaviour among non-insulin treated patients with type 2 diabetes mellitus, and to evaluate associations with glycaemic control.

METHODS

Eligible patients in 23 GP practices in Tayside, Scotland, were identified (18-75 years, no insulin treatment, SMBG reagent strips dispensed in 2009). Consenting patients were administered questionnaires addressing SMBG behaviour: these primary data were record-linked to clinical data (including HbA1c) from a validated population-based diabetes clinical information system, then anonymised.

RESULTS

Among 629 eligible patients, 207 were interviewed and analysed. Mean SMBG reagent strips dispensed in 12 months was 268. In response to a perceived high test result, 80 (38.8%) patients took no action or simply checked later with most of them (61.3%) indicating they did not know what action to take. Of the 126 (61.2%) patients who took some action, 101 made changes to diet, 12 increased physical activity, 10 made changes to medication and 12 mad a HCP appointment. A high score on a Diabetes Knowledge Test was a statistically significant predictor of taking action (odds ratio: 2.07). However, neither taking action nor increased SMBG frequency was associated with improved glycaemic control.

CONCLUSIONS

Responding to SMBG test results and increased testing frequency were not associated with improved glycaemic control in the short-term. There is a lack of knowledge surrounding SMBG in non-insulin treated patients.

Factors associated with poor glycemic control or wide glycemic variability among diabetes patients in Hawaii, 2006-2009

Introduction

Although glycemic control is known to reduce complications associated with diabetes, it is an elusive goal for many patients with diabetes. The objective of this study was to identify factors associated with sustained poor glycemic control, some glycemic variability, and wide glycemic variability among diabetes patients over 3 years.

Methods

This retrospective study was conducted among 2,970 diabetes patients with poor glycemic control (hemoglobin A1c [HbA1c] >9%) who were enrolled in a health plan in Hawaii in 2006. We conducted multivariable logistic regressions to examine factors related to sustained poor control, some glycemic variability, and wide glycemic variability during the next 3 years. Independent variables evaluated as possible predictors were age, sex, type of insurance coverage, morbidity, diabetes duration, history of cardiovascular disease, and number of medications.

Results

Longer duration of diabetes, being under age 35, and taking 15 or more medications were significantly associated with sustained poor glycemic control. Preferred provider organization and Medicare (vs health maintenance organization) enrollees and patients with high morbidity were less likely to have sustained poor glycemic control. Wide glycemic variability was significantly related to being younger than age 50, longer duration of diabetes, having coronary artery disease, and taking 5 to 9 medications per year.

Conclusion

Results indicate that duration of diabetes, age, number of medications, morbidity, and type of insurance coverage are risk factors for sustained poor glycemic control. Patients with these characteristics may need additional therapies and targeted interventions to improve glycemic control. Patients younger than age 50 and those with a history of coronary heart disease should be warned of the health risks of wide glycemic variability.

Patient factors and glycaemic control--associations and explanatory power

AIMS

To investigate the association between glycaemic control and patient socio-demographics, activation level, diabetes-related distress, assessment of care, knowledge of target HbA(1c), and self-management behaviours, and to determine to what extent these factors explain the variance in HbA(1c) in a large Danish population of patients with Type 2 diabetes.

METHODS

Cross-sectional survey and record review of 2045 patients from a specialist diabetes clinic. Validated scales measured patient activation, self-management behaviours, diabetes-related emotional distress, and perceived care. The electronic patient record provided information about HbA(1c), medication, body mass index, and duration of diabetes. Data were analysed using multiple linear regression models with stepwise addition of covariates.

RESULTS

The response rate was 54% (n = 1081). Good glycaemic control was significantly associated with older age, higher education, higher patient activation, lower diabetes-related emotional distress, better diet and exercise behaviours, lower body mass index, shorter duration of disease and knowledge of HbA(1c) targets (P < 0.05 for all). Patient socio-demographics, behaviour; perceptions of care and diabetes distress accounted for 14% of the total variance in HbA(1c) levels (P = 0.0134), but the variance explained was higher for respondents treated with medications other than insulin.

CONCLUSIONS

Our study emphasizes the complex relationships between patient activation, distress and behaviour, specific treatment modalities and glycaemic control. Knowledge of treatment goals, achieving patient activation in coping with diabetes, and lowering disease-related emotional stress are important patient education goals. However, the large unexplained component of HbA(1c) variance highlights the need for more research to understand the mechanisms of glycaemic control.

Diabetes self-efficacy strongly influences actual control of diabetes in patients attending a tertiary hospital in India

A cross-sectional survey of 507 in- and out-patients, with diagnosed Type 2 diabetes mellitus (T2DM) was undertaken to study the relationships between personal, disease and treatment-related factors and diabetes control in a tertiary care hospital. On multivariate logistic regression analysis, self-efficacy (odds ratio (OR) =2.94; 95% confidence interval (CI) =1.92-4.54); P<0.001) was the single most important determinant of current diabetes control (HbA1c ≤7%), along with absence of hyperglycemic symptoms in the past year (OR=1.83; 95% CI=1.15-2.93, P<0.01), current treatment with oral medication (OR=1.77; 95% CI=1.17-2.66; P<0.007), and adherence to dietary restrictions (OR=2.7; 95% CI=1.28-5.88; P<0.009). Self-efficacy was itself influenced by educational status, employment, availability of family support, and positive mental attitudes. Our findings suggest that health care delivery inputs, patients' personal characteristics including education and attitude, and family support for care are complexly processed to determine patients' ability to manage their disease, which ultimately influences disease outcomes.

The use of pioglitazone and the risk of bladder cancer in people with type 2 diabetes: nested case-control study

OBJECTIVE

To determine if the use of pioglitazone is associated with an increased risk of incident bladder cancer in people with type 2 diabetes.

DESIGN

Retrospective cohort study using a nested case-control analysis.

SETTING

Over 600 general practices in the United Kingdom contributing to the general practice research database.

PARTICIPANTS

The cohort consisted of people with type 2 diabetes who were newly treated with oral hypoglycaemic agents between 1 January 1988 and 31 December 2009. All incident cases of bladder cancer occurring during follow-up were identified and matched to up to 20 controls on year of birth, year of cohort entry, sex, and duration of follow-up. Exposure was defined as ever use of pioglitazone, along with measures of duration and cumulative dosage.

MAIN OUTCOME MEASURE

Risk of incident bladder cancer associated with use of pioglitazone.

RESULTS

The cohort included 115,727 new users of oral hypoglycaemic agents, with 470 patients diagnosed as having bladder cancer during follow-up (rate 89.4 per 100,000 person years). The 376 cases of bladder cancer that were diagnosed beyond one year of follow-up were matched to 6699 controls. Overall, ever use of pioglitazone was associated with an increased rate of bladder cancer (rate ratio 1.83, 95% confidence interval 1.10 to 3.05). The rate increased as a function of duration of use, with the highest rate observed in patients exposed for more than 24 months (1.99, 1.14 to 3.45) and in those with a cumulative dosage greater than 28,000 mg (2.54, 1.05 to 6.14).

CONCLUSION

The use of pioglitazone is associated with an increased risk of incident bladder cancer among people with type 2 diabetes.

Factors associated with poor glycemic control in older Mexican American diabetics aged 75 years and older

OBJECTIVE

This study examines the prevalence and correlates of poor glycemic control in Mexican Americans aged 75 years and older with diabetes.

METHODS

Data are from the 5(th) wave (2004-05) of the Hispanic Established Population for the Epidemiological Study of the Elderly (H-EPESE). A total of 2,069 Mexican Americans aged 75 and over were interviewed. Six hundred eighty nine subjects (33.5%) reported having been diagnosed with diabetes and 209 (30.3%) subjects agreed to a blood test of their HbA(1)c level.

RESULTS

Of the 209 diabetic subjects with an HbA(1)c test, 73 (34.9%) had good glycemic control (HbA(1)c <7%) and 136 (65.1%) had poor glycemic control (HbA(1)c >7%). Bivariate analysis revealed that subjects with poor control had longer disease duration, had lower education, used the glucometer more frequently, and had more diabetes-complications when compared to those in the good glycemic control group. Multivariable logistic regression analysis found the following factors associated with poor glycemic control: <8 years of education, foreign-born, smoking, obesity, longer disease duration, daily glucometer use, and having macro-complications.

DISCUSSION

Prevalence of poor glycemic control is very high in this population with very high and rising prevalence of diabetes. Further studies are needed to explore the effect of these and other characteristics on glycemic control among older Mexican Americans and to develop appropriate interventions to improve diabetes outcomes and increase life-expectancy.

Predictors of suboptimal glycaemic control in type 2 diabetes patients: the role of medication adherence and body mass index in the relationship between glycaemia and age

AIMS

To analyse predictors of glycaemic control including medication adherence and body mass index (BMI) in UK general practice patients with sub-optimally controlled type 2 diabetes.

METHODS

Baseline demographic, health- and treatment-related measures were evaluated as predictors of one year glycaemic control defined separately as HbA(1c)≤ 7.5% and a continuous measure of HbA(1c) concentration, using multivariate regression models. Significant predictors were adjusted for objectively assessed medication adherence and BMI.

RESULTS

One-year HbA(1c) concentration was associated with baseline HbA(1c) (p<0.001), BMI (p=0.02), and inversely associated with age (p=0.007) and objectively assessed adherence. Adherent patients had one-year (adjusted) HbA(1c) concentration 0.65% (95% CI -1.04, -0.25; p=0.001) lower than nonadherent. Odds ratios (95% CI) of HbA(1c)≤ 7.5% for 10-year higher age were 1.63 (1.08, 2.45); for adherent compared to non-adherent patients 1.89 (0.84, 4.25); for patients receiving >5 compared to ≤ 5 medications 0.32 (0.13, 0.76); and for each 1% increment in baseline HbA(1c) 0.48 (0.31, 0.73).

CONCLUSIONS

The lower HbA(1c) achieved from greater adherence to glucose lowering treatment is comparable to that achieved with additional medication. Relationships between older age and better glycaemic control are not explained by better adherence, but may partly relate to lower BMI.

Predictors of poor glycaemic control during the initial five years post-diagnosis in rural adults with type 2 diabetes

OBJECTIVE

To identify factors predicting suboptimal glycaemic control in rural adults during the initial five years post-type 2 diabetes diagnosis.

DESIGN

Retrospective medical record audit. Quantitative study.

SETTING

Rural community-based primary health service, South Gippsland, Victoria, Australia.

PARTICIPANTS

Two hundred and seventy-two de-identified medical records randomly selected from the type 2 diabetes outpatient database.

MAIN OUTCOME MEASURES

Demographic, biochemical, anthropometric, pharmacological, co-morbidity and lifestyle data during the first five years post-diabetes diagnosis were retrospectively collected. Univariate analysis was performed to identify variables associated with poor diabetes control (HbA1c ≥ 7%).

RESULTS

Independent predictors of poor glycaemic control in this rural cohort were elevated fasting glucose at diagnosis (odds ratio (OR) 1.97, 95% confidence interval (CI) 1.31-2.97, P < 0.001), weight gain during the initial 2.5 years of diabetes (OR 1.33, 95% CI 1.11-1.59, P < 0.01), excessive body weight at diagnosis (OR 1.07, 95% CI 1.03-1.12, P < 0.001) and younger age at diagnosis (OR 0.94, 95% CI 0.88-1.00, P < 0.05). These variables combined explained 48% of the variation in HbA1c. Gender, body mass index, waist circumference and lifestyle factors at diagnosis were not significant predictors of diabetes control.

CONCLUSIONS

Young-middle-aged adults (≤58 years) with elevated fasting glucose (≥9.0 mmol L(-1) ) and excessive body weight (≥93.1 kg) at type 2 diabetes diagnosis and those unable to lose weight early in the course of the disease are more likely to experience a rapid deterioration in glucose control. Rural clinicians should target these individuals for aggressive diabetes management from the time of diagnosis.

Predictors of adherence with self-care guidelines among persons with type 2 diabetes: results from a logistic regression tree analysis

Type 2 diabetes is known to contribute to health disparities in the U.S. and failure to adhere to recommended self-care behaviors is a contributing factor. Intervention programs face difficulties as a result of patient diversity and limited resources. With data from the 2005 Behavioral Risk Factor Surveillance System, this study employs a logistic regression tree algorithm to identify characteristics of sub-populations with type 2 diabetes according to their reported frequency of adherence to four recommended diabetes self-care behaviors including blood glucose monitoring, foot examination, eye examination and HbA1c testing. Using Andersen's health behavior model, need factors appear to dominate the definition of which sub-groups were at greatest risk for low as well as high adherence. Findings demonstrate the utility of easily interpreted tree diagrams to design specific culturally appropriate intervention programs targeting sub-populations of diabetes patients who need to improve their self-care behaviors. Limitations and contributions of the study are discussed.

Impact of insurance status on access to care and out-of-pocket costs for U.S. individuals with epilepsy

We analyzed data from the 2002-2007 Medical Expenditure Panel Survey (MEPS) to assess whether individuals with epilepsy who are uninsured and those who have Medicaid coverage experience differences in medical resource utilization or out-of-pocket costs compared with those having other types of insurance. With sociodemographic characteristics controlled for, uninsured individuals had significantly fewer outpatient visits, fewer visits with neurologists, and greater antiepileptic drug costs than did those with private insurance. Individuals with Medicaid coverage had similar medical resource utilization rates but lower out-of-pocket costs compared with privately insured individuals. These findings indicate substantial barriers to receipt of appropriate medical care for uninsured individuals with epilepsy, but not for those with Medicaid coverage. Future studies should evaluate whether ongoing changes to the US health care system are able to address the differences in care we found among uninsured individuals with epilepsy and should incorporate measures of disease severity and unmet need.

Frequency of Monitoring Hemoglobin A1C and Achieving Diabetes Control

OBJECTIVES

The American Diabetes Association recommends measuring hemoglobin A1C levels (A1C) at least semiannually in diabetic patients who have stable glycemic control and quarterly in patients whose therapy has changed or who are not meeting glycemic goals. These guidelines were based on expert consensus without reference to actual clinical data. The main objective of this study was to assess association between meeting a target A1C level of <7% and adherence to monitoring guidelines. Secondary objectives were to determine the proportion of diabetic patients in the authors' practice who met the A1C monitoring guidelines and to assess whether meeting the target A1C level is associated with other information easily abstracted from patients records, namely age, gender, and types of therapy.

METHODS

This study employed a case control design. Records of 193 type 2 diabetic patients seen over a 6-month period in a rural family medicine clinic were analyzed. Assessment of diabetes control was based on the most recent A1C level, with <7% considered controlled. Adherence to guidelines was assessed by determining frequency of testing during the preceding 12-month period.

RESULTS

Ninety-eight patients (51%) adhered to the American Diabetes Association guidelines on frequency of monitoring A1C. Median levels of adherent and nonadherent patients differed significantly (6.5 vs 7.3, P < .001, Mann-Whitney test). Logistic regression analysis showed that "diabetes control" based on the A1C level is positively associated with adherence to the guidelines, negatively associated with intensity of therapy, and not associated with gender or age.

CONCLUSION

This study supports the usefulness of American Diabetes Association practice guidelines on the frequency of monitoring A1C levels in diabetic patients.

Race differences in access to health care and disparities in incident chronic kidney disease in the US

BACKGROUND

The contribution of race differences in access to health care to disparities in chronic kidney disease (CKD) incidence in the United States is unknown.

METHODS

We examined race differences in usual source of health care, health insurance and CKD incidence among 3883 Whites and 1607 Blacks with hypertension or diabetes enrolled in the Atherosclerosis Risk in Communities Study. In multivariable analyses, we explored the incremental contribution of access to health care in explaining Blacks' excess CKD incidence above and beyond other socioeconomic, lifestyle and clinical factors.

RESULTS

Compared with Whites, Blacks had poorer access to health care (3 vs 0.3% with no usual source of health care or health insurance, P < 0.001) and experienced greater CKD incidence (14.7 vs 12.0 cases per 1000 person-years, P < 0.001). Blacks' excess risk of CKD persisted after adjusting for demographic, socioeconomic, lifestyle and clinical factors [hazard ratio (HR) (95% confidence interval (95% CI)) = 1.21 (1.01-1.47)]. Adjustment for these factors explained 64% of the excess risk among Blacks. The increased risk for CKD among Blacks was attenuated after additional adjustment for race differences in access to health care [HR (95% CI) = 1.19 (0.99-1.45)], which explained an additional 10% of the disparity. Conclusions. In this population at risk for developing CKD, we found that poorer access to health care among Blacks explained some of Blacks' excess risk of CKD, beyond the excess risk explained by demographic, socioeconomic, lifestyle and clinical factors. Improved access to health care for high-risk individuals could narrow disparities in CKD incidence.

Glycemic control in HIV-infected patients with diabetes mellitus and rates of meeting American Diabetes Association management guidelines

Limited data exist on the prevalence of inadequate glycemic control and rates of meeting American Diabetic Association (ADA) management guidelines in HIV-infected adults with diabetes mellitus. We conducted a retrospective cross-sectional study of 142 HIV-infected adults with type 2 diabetes at an urban academic HIV clinic during 2008. We estimated the prevalence of and assessed associations with inadequate glycemic control, defined as hemoglobin A(1c) ≥ 7.5% for ≥ 50% of quarters over the year, and determined rates of meeting ADA clinical goals. Ninety-two percent of patients received antiretroviral therapy. The prevalence of inadequate glycemic control was 33% (95% confidence interval [CI] 25%-42%). Compared to patients with adequate control, those with inadequate control had fewer years since HIV diagnosis (12.7 versus 15.1, p = 0.01), increased use of insulin (60% versus 20%, p < 0.001) or any diabetic medication (98% versus 85%, p = 0.02), and higher triglyceride levels (238 versus 168 mg/dL, p = 0.008). Rates of achieving ADA goals were 42% for blood pressure, 66% for low-density lipoprotein cholesterol (LDL-C), 33% for high-density lipoprotein cholesterol, and 31% for triglycerides. Thirty-six percent of patients who did not meet the LDL-C goal received statin therapy. Forty-seven percent of patients were screened for retinopathy and 19% of patients without preexisting renal disease were screened for nephropathy. In conclusion, the prevalence of inadequate glycemic control in HIV-infected patients with diabetes is similar to published data from the general population. Suboptimal rates of meeting ADA blood pressure and lipid goals and adherence to screening guidelines demonstrate need for further clinician and patient education.

Metformin and the incidence of prostate cancer in patients with type 2 diabetes

BACKGROUND

Several in vitro studies have indicated that metformin may reduce the risk of prostate cancer; however, epidemiologic studies have been inconclusive. The objective of this study was to determine whether metformin decreases the risk of prostate cancer in patients with type 2 diabetes.

METHODS

A nested case-control analysis was conducted within a population-based cohort from the UK General Practice Research Database. The cohort included patients over the age of 40 who were prescribed a first oral hypoglycemic agent (OHA) between 1988 and 2009. Cases of prostate cancer were matched up to ten controls on year of birth, date of cohort entry, and duration of follow-up. Adjusted rate ratios (RR) were estimated using conditional logistic regression.

RESULTS

The cohort included 63,049 incident users of OHAs, in which 739 cases of prostate cancer were matched to 7,359 controls. Metformin use did not decrease the risk of prostate cancer (RR: 1.23, 95% CI: 0.99-1.52). In secondary analyses, prostate cancer risk was found to increase as a function of the number of metformin prescriptions received (one to seven prescriptions: RR: 1.05, 95% CI: 0.80-1.37; seven to eighteen prescriptions: RR: 1.29, 95% CI: 0.99-1.69; eighteen to thirty-six prescriptions: RR: 1.37, 95% CI: 1.04-1.81; more than thirty-six prescriptions: RR: 1.40, 95% CI: 1.03-1.89).

CONCLUSION

The results of this study indicate that metformin does not reduce the risk of prostate cancer in patients with type 2 diabetes.

IMPACT

The secondary analyses need to be interpreted with caution given the inverse association between type 2 diabetes and prostate cancer.

A review of treatment response in type 2 diabetes: assessing the role of patient heterogeneity

The response to treatment for type 2 diabetes typically varies among individuals within a study population. This variation is known as heterogeneity of treatment response. We conducted a comprehensive literature review to identify factors that account for heterogeneity of treatment response in patients treated for type 2 diabetes. Three databases (PubMed, EMBASE and Cochrane Library) were searched for articles published in the last 10 years describing investigations of factors associated with treatment response and outcomes among people with type 2 diabetes receiving pharmacological treatment. Of the 43 articles extracted and summarized, 35 (81%) discussed clinical factors, 31 (72%) described sociodemographic factors and 17 (40%) reported on comorbidity or behavioural factors. Clinical factors identified included baseline glycated hemoglobin A1c or fasting plasma glucose (FPG) levels, insulin response or sensitivity, C-peptide, body composition, adipose tissue proteins, lipid profile, plasma albumin levels and duration of disease or insulin treatment. Other factors identified included age, sex, race, socioeconomic status and comorbidities. This review identified the following research gaps: use of multiple definitions for response, few patient-reported measures and lack of evidence regarding whether factors were associated with treatment response for only specific medications or across pharmacological therapies. Furthermore, identification of factors associated with type 2 diabetes treatment response was generally a secondary objective in the research reviewed. Understanding which patient subgroups are more likely to respond to treatment and identifying factors associated with response may result in targeted treatment decisions and alter the interpretation of efficacy or effectiveness of results. In conclusion, accounting for these factors in clinical trials and when making clinical treatment decisions may improve therapy selection and individual patient outcomes.

Monitoring modifiable cardiovascular risk in type 2 diabetes care in general practice: the use of an aggregated z-score

BACKGROUND

Because many patients in usual care reach the diabetes treatment goals, it may be more efficacious to focus quality improvement efforts on those general practice populations requiring additional support. We therefore developed a tool based on a composite end point considering blood pressure, lipids, and glycaemia.

METHODS

We created an aggregated z(A)-score, calculated as the average of 3 z-scores testing whether the mean practice values of hemoglobin A1c, low density lipoprotein cholesterol, and systolic blood pressure are significantly higher than the corresponding ADA-target (respectively 7%, 100 mg/dL, and 130 mm Hg). This score was used with 100 general practitioners who participated in a Quality Improvement Program. We defined the cut-off value (COV) to determine "Practices Requiring Support" (z(A) <COV) using a receiver's operating characteristics curve with the mean practice CHD risk as gold standard. To further test the z-score validity, we calculated the correlation coefficient between the z-score and the mean practice CHD risk and the improvement in the z-score after the Quality Improvement Program.

RESULTS

The COV was -1.22 and was valid to discriminate between practices at higher risk from practices at lower CHD risk (24% +/- 4% vs. 19% +/- 4%). The correlation coefficient was -0.515 (P = 0.001). The average z-score increased from -1.21 +/- 0.97 at baseline to 0.49 +/- 1.01 after the intervention (P < 0.001).

CONCLUSION

This scoring system is useful to picture practice populations with diabetes who are at high cardiovascular risk because of modifiable risk factors. Although the unadjusted z-score cannot be used to compare physicians, this technique can be used to evaluate improvement efforts over time.

Plasma C-peptide level is inversely associated with family history of type 2 diabetes in Korean type 2 diabetic patients

Type 2 diabetes is characterized by progressive β-cell dysfunction. Family history of type 2 diabetes has been known to be associated with an increased risk for the development of the disease. However, few studies have evaluated the effects of family history of diabetes on residual β-cell function in type 2 diabetic patients. We investigated associations among family histories, clinical characteristics and plasma C-peptide levels in type 2 diabetic patients. A total of 1,350 patients with type 2 diabetes were recruited. The patients with a family history of type 2 diabetes had younger age at onset of diabetes, longer diabetes duration, higher LDL-cholesterol, and lower fasting C-peptide levels than the patients without family history. When divided according to the tertiles of diabetes duration, patients with a family history of type 2 diabetes had more decreased concentrations of fasting C-peptide as duration of diabetes increased, but patients without a family history did not. Multiple regression models were used to determine the association between fasting plasma C-peptide levels and a family history of type 2 diabetes mellitus. With adjustments for age and sex, glycated hemoglobin (HbA(1C)), fasting plasma glucose, free fatty acids, body mass index and diabetes mellitus (DM) duration, there was a significant association (P < 0.01). Our results showed that a family history of diabetes was significantly associated with the progressive decline of fasting plasma C-peptide levels in Korean type 2 diabetes mellitus.

Factors predicting glycemic control in middle-aged and older adults with type 2 diabetes

INTRODUCTION

Few studies have prospectively assessed the explanatory effects of demographics, clinical conditions, treatment modality, and general lifestyle behaviors on glycemic control in large heterogeneous samples of middle-aged and older adults with type 2 diabetes. We hierarchically examined these factors, focused especially on the effects of modifiable factors (ie, general lifestyle behaviors), and compared predictive patterns between middle-aged and older adults.

METHODS

We used nationally representative data from the 1998 and 2000 Health and Retirement Study (HRS) and the HRS 2003 Diabetes Study. We analyzed data from 379 middle-aged adults (aged 51-64 y) and 430 older adults (aged >or=65 y) who self-reported having type 2 diabetes at baseline.

RESULTS

Among middle-aged adults, demographic factors and clinical conditions were the strongest predictors of hemoglobin A1c (HbA1c) levels. However, among older adults, treatment modality (diet only, oral medication, or insulin only or in combination with other regimens) significantly affected HbA1c levels. Lifestyle (physical activity, smoking, drinking, and body weight control), independent of the effects of demographics, clinical conditions, and treatment modality, significantly affected HbA1c levels. An increase of 1 healthy behavior was associated with a decrease in HbA1c levels of more than 1 percentage point.

CONCLUSION

Our findings provide support for current diabetes guidelines that recommend a lifestyle regimen across the entire span of diabetes care and highlight the need to help both sociodemographically and clinically disadvantaged middle-aged adults with type 2 diabetes as well as older adults who exhibit poor adherence to medication recommendations to achieve better glycemic control.

Use of the emergency department for less-urgent care among type 2 diabetics under a disease management program

Background

This study analyzed the likelihood of less-urgent emergency department (ED) visits among type 2 diabetic patients receiving care under a diabetes disease management (DM) program offered by the Louisiana State University Health Care Services Division (LSU HCSD).

Methods

All ED and outpatient clinic visits made by 6,412 type 2 diabetic patients from 1999 to 2006 were extracted from the LSU HCSD Disease Management (DM) Evaluation Database. Patient ED visits were classified as either urgent or less-urgent, and the likelihood of a less-urgent ED visit was compared with outpatient clinic visits using the Generalized Estimating Equation methodology for binary response to time-dependent variables.

Results

Patients who adhered to regular clinic visit schedules dictated by the DM program were less likely to use the ED for less urgent care with odds ratio of 0.1585. Insured patients had 1.13 to 1.70 greater odds of a less-urgent ED visit than those who were uninsured. Patients with better-managed glycated hemoglobin (A1c or HbA1c) levels were 82 times less likely to use less-urgent ED visits. Furthermore, being older, Caucasian, or a longer participant in the DM program had a modestly lower likelihood of less-urgent ED visits. The patient's Charlson Comorbidity Index (CCI), gender, prior hospitalization, and the admitting facility showed no effect.

Conclusion

Patients adhering to the DM visit guidelines were less likely to use the ED for less-urgent problems. Maintaining normal A1c levels for their diabetes also has the positive impact to reduce less-urgent ED usages. It suggests that successful DM programs may reduce inappropriate ED use. In contrast to expectations, uninsured patients were less likely to use the ED for less-urgent care. Patients in the DM program with Medicaid coverage were 1.3 times more likely to seek care in the ED for non-emergencies while commercially insured patients were nearly 1.7 times more likely to do so. Further research to understand inappropriate ED use among insured patients is needed. We suggest providing visit reminders, a call centre, or case managers to reduce the likelihood of less-urgent ED visit use among DM patients. By reducing the likelihood of unnecessary ED visits, successful DM programs can improve patient care.

Factors associated with poor glycemic control among patients with type 2 diabetes

OBJECTIVES

Determine factors associated with poor glycemic control among Jordanian patients with Type 2 diabetes.

METHODS

A systematic random sample of 917 patients was selected from all patients with Type 2 diabetes over a period of 6 months in 2008. A prestructured questionnaire sought information about sociodemographic, clinical characteristics, self-care management behaviours, medication adherence, barriers to adherence, and attitude towards diabetes. Weight, height, and waist circumferences were measured. All available last readings of hemoglobin A1c (HbA1c), fasting blood sugar measurements and lipid were abstracted from patients' records. Poor glycemic control was defined as HbA1c >or=7%.

RESULTS

Of the total 917 patients, 65.1% had HbA1c >or=7%. In the multivariate analysis, increased duration of diabetes (>7 years vs. <or=7years) (OR=1.99, P<or=.0005), not following eating plan as recommended by dietitians (OR=2.98, P<or=.0005), negative attitude towards diabetes, and increased barriers to adherence scale scores were significantly associated with increased odds of poor glycemic control.

CONCLUSION

The proportion of patients with poor glycemic control was high, which was nearly comparable to that reported from many countries. Longer duration of diabetes and not adherent to diabetes self-care management behaviors were associated with poor glycemic control. An educational program that emphasizes lifestyle modification with importance of adherence to treatment regimen would be of great benefit in glycemic control.

Clinical predictors of disease progression and medication initiation in untreated patients with type 2 diabetes and A1C less than 7%

OBJECTIVE

Many patients with early diabetes remain untreated. Our objectives were to identify clinical predictors of 1) worsening glycemic control and 2) medical treatment initiation in response to worsening glycemic control among patients with type 2 diabetes.

RESEARCH DESIGN AND METHODS

We identified 5,804 type 2 diabetic patients seen at least twice between June 2005 and June 2006 within our 12-clinic primary care network. We examined predictors of diabetes progression (A1C >or=7% or initiation of hypoglycemic agent) over a 1-year follow-up period in 705 patients who had A1C <7% and were not on glucose-lowering medications at baseline. In the 200 patients in this group who progressed, we examined predictors of medical therapy initiation.

RESULTS

In multivariate analyses, baseline A1C (P < 0.0001), younger age (P = 0.04), and weight gain (P = 0.03) were independent predictors of progression after adjusting for race, sex, and baseline HDL levels. Each decade of increasing age reduced the risk of progression by 15%. Each 1-lb increase in weight was associated with a 2% increased odds of progression. Likelihood of medication initiation among progressors decreased by 40% (P = 0.02) with every decade of age and decreased by 2.3% (P = 0.02) with each 1-mg/dl decrease in LDL level from baseline after adjusting for race, sex, and weight change.

CONCLUSIONS

Among untreated primary care patients with type 2 diabetes and A1C <7%, younger patients and those with weight gain were more likely to have diabetes progression and should be the focus of aggressive diabetes management.

Can we predict future improvement in glycaemic control?

AIMS

To determine the factors responsible for poor glycaemic control in diabetes and whether any such factors are associated with likely improvement in glycaemic control.

METHODS

A prospective cohort study of 130 diabetic patients with poor glycaemic control (HbA(1c )> or = 10.0%) with 1-year follow-up in a teaching hospital Diabetes Clinic. Changes in HbA(1c) were measured after 1 year.

RESULTS

Poor glycaemic control was attributed to one of 15 possible causes. Those cases due to recent diagnosis of diabetes, inadequate treatment with diet, oral glucose-lowering agents or insulin, exacerbation of co-existent medical problems, recent stressful life-events and missed clinic appointments were all associated with significant improvement in HbA(1c) at 12 months. Patients with low mood or alcohol excess, inadequate blood glucose monitoring, poor exercise/sedentary lifestyle, refusal to take tablets or underdosing and refusal to take insulin at all or to increase the dose were all associated with continuing poor glycaemic control at 12 months. The patients were divided almost equally between the two groups.

CONCLUSIONS

In patients with poor glycaemic control, it is possible by simple features identified at clinic to predict which individuals are likely to show improvement in control and which will not. These findings have not been reported previously and suggest that about half of individuals with poor control will improve within our current diabetes clinic practice. Additional strategies will be required to address those individuals who are not likely to respond.

Variation in antidiabetic medication intensity among Medicare beneficiaries with diabetes mellitus

BACKGROUND

Recent guidelines for treating older patients with diabetes mellitus (DM) and significant disease burden place less emphasis on glycemic control and stress the potential harms that may arise from adherence to strict regimens with antidiabetic medications. However, there are few empirical benchmarks against which clinicians can compare their prescribing practices for patients who have DM and varying levels of comorbidity.

OBJECTIVE

The current study had 2 goals: (1) to provide national estimates showing how the intensity of antidiabetic medication regimens for Medicare beneficiaries with DM varies by level of medical spending (a proxy for overall disease burden); and (2) to identify potential predictive factors associated with the observed differences.

METHODS

This study analyzed 2002 Medicare Current Beneficiary Survey (MCBS) data to benchmark intensity of antidiabetic medication regimens for Medicare beneficiaries with DM arrayed by decile of cumulative medical care spending. The study involved 3 steps: (1) stratification of the study population into 10 mutually exclusive deciles by cumulative all-source annual medical spending; (2) assessment of the unconditional association between decile assignment and intensity of antidiabetic medication use; and (3) identification of mediating factors that differentially explain medication intensity across the spectrum of disease burden. We evaluated 3 outcomes: (1) prevalence of any antidiabetic agent in 2002; (2) annual utilization rates for 5 different classes of oral hypoglycemic agents (sulfonylurea, metformin, thiazolidinedione, alpha-glucosidase inhibitors, and meglitinides) plus insulins; and (3) counts of annual prescription fills.

RESULTS

The final study sample comprised 1956 Medicare beneficiaries representing 23.1% of the MCBS sample after exclusions. We found a pronounced inverted U-shaped pattern in intensity of antidiabetic treatment. Compared with individuals in the group with the highest prevalence of antidiabetic use (decile 7), the unadjusted treatment odds ratios were 0.40 in decile 1 (95% CI, 0.26-0.60) and 0.54 in decile 10 (95% CI, 0.36-0.81). We found similar patterns in the complexity of drug regimens and numbers of antidiabetic prescriptions filled among users. Controlling for disease severity and other factors eliminated the inverted U-shaped pattern among higher cost beneficiaries but not for those in the lower spending deciles.

CONCLUSIONS

This national study found that high-cost Medicare beneficiaries with DM received substantially less intensive antidiabetic regimens compared with those incurring more modest medical expenditures in 2002. Longitudinal analysis is necessary to determine whether this finding indicates suboptimal therapy or has a more benign explanation. However, the magnitude of the association warrants the attention of clinicians who treat elderly and disabled diabetic patients with high disease burden.

Antidiabetic prescriptions and glycemic control in German patients with type 2 diabetes mellitus: a retrospective database study

OBJECTIVES

This study examined patterns of antidiabetic treatment among individuals with type 2 diabetes in Germany and investigated potential differences in attainment of glycemic control associated with the use of specific antidiabetic regimens.

METHODS

This was a retrospective database study. Data were obtained from the German IMS Disease Analyzer-MediPlus database. Patients aged >or=20 years who were identified as having type 2 diabetes and who underwent glycosylated hemoglobin (HbA(1c)) testing at least once between April 1, 2004, and December 31, 2004, were included in the analyses. Potential associations between age, sex, and diabetic complications and the use of specific antidiabetic medications were examined. Also examined were potential associations between attainment of the HbA(1c) target for glycemic control (56.5%), particular patient characteristics, and the use of specific antidiabetic medications.

RESULTS

The study included data from 5135 patients with type 2 diabetes (mean age, 67 years; 2702 men, 2433 women; mean [SD] HbA(1c), 6.9% [1.2%]). The most commonly diagnosed comorbidities were hypertension (66.5%) and obesity (18.7%). There were no significant differences in mean age, sex, or comorbidities between patients categorized by HbA(1c) values <or=56.5% or >6.5%. The most commonly prescribed antidiabetic medications were metformin (20.4%), a sulfonylurea (11.7%), and oral combination therapy (10.9%). In the assessment of potential associations between selected patient characteristics and the receipt of specific antidiabetic medications, individuals were less likely to receive metformin monotherapy if they were aged >or=75 years (12.0%, compared with 21.4% of those aged 65-74 years and 24.7% of those aged <65 years; P < 0.001) or had a diagnosis of a diabetic complication (15.9%, compared with 21.2% in those without complications; P < 0.001). Among those who were more likely to receive insulin monotherapy were women (11.5%, compared with 9.6% of men; P = 0.025) and patients with diabetic complications (13.9%, compared with 9.8% of those without complications; P < 0.001). More than half (52.7%) of patients did not attain the HbA(1c) target. There were significant differences between patients attaining the HbA(1c) target and receipt of specific antidiabetic medications (P < 0.001). Patients treated with insulin monotherapy or oral plus insulin combination therapy were least likely to reach the HbA(1c) target (26.4% and 22.9%, respectively, attained glycemic control; both, P < 0.001). Only 179 (31.9%) of 562 patients treated with oral combination therapy achieved the HbA(1c) target (P < 0.001).

CONCLUSIONS

Over half of these German patients with type 2 diabetes failed to attain the HbA(1c) target for glycemic control. Patients who were prescribed insulin monotherapy or combination therapy were least likely to achieve the target.

The kinin system mediates hyperalgesia through the inducible bradykinin B1 receptor subtype: evidence in various experimental animal models of type 1 and type 2 diabetic neuropathy

Both insulin-dependent (type 1) and insulin-independent (type 2) diabetes are complex disorders characterized by symptomatic glucose intolerance due to either defective insulin secretion, insulin action or both. Unchecked hyperglycemia leads to a series of complications among which is painful diabetic neuropathy, for which the kinin system has been implicated. Here, we review and compare the profile of several experimental models of type 1 and 2 diabetes (chemically induced versus gene-prone) and the incidence of diabetic neuropathy upon aging. We discuss the efficacy of selective antagonists of the inducible bradykinin B1 receptor (BKB1-R) subtype against hyperalgesia assessed by various nociceptive tests. In either gene-prone models of type 1 and 2 diabetes, the incidence of hyperalgesia mostly precedes the development of hyperglycemia. The administration of insulin, achieving euglycemia, does not reverse hyperalgesia. Treatment with a selective BKB1-R antagonist does not affect basal nociception in most normal control rats, whereas it induces a significant time- and dose-dependent attenuation of hyperalgesia, or even restores nociceptive responses, in experimental diabetic neuropathy models. Diabetic hyperalgesia is absent in streptozotocin-induced type 1 diabetic BKB1-R knockout mice. Thus, selective antagonism of the inducible BKB1-R subtype may constitute a novel and potential therapeutic approach for the treatment of painful diabetic neuropathy.