Oxidative Stress and Cardiovascular Risk in Type 1 Diabetes Mellitus: Insights From the DCCT/EDIC Study

Background

Hyperglycemia leading to increased oxidative stress is implicated in the increased risk for the development of macrovascular and microvascular complications in patients with type 1 diabetes mellitus.

Methods and Results

A random subcohort of 349 participants was selected from the DCCT / EDIC (Diabetes Control and Complications Trial/Epidemiology of Diabetes Interventions and Complications) cohort. This included 320 controls and 29 cardiovascular disease cases that were augmented with 98 additional known cases to yield a case cohort of 447 participants (320 controls, 127 cases). Biosamples from DCCT baseline, year 1, and closeout of DCCT , and 1 to 2 years post‐ DCCT ( EDIC years 1 and 2) were measured for markers of oxidative stress, including plasma myeloperoxidase, paraoxonase activity, urinary F 2α isoprostanes, and its metabolite, 2,3 dinor‐8 iso prostaglandin F 2α . Following adjustment for glycated hemoblobin and weighting the observations inversely proportional to the sampling selection probabilities, higher paraoxonase activity, reflective of antioxidant activity, and 2,3 dinor‐8 iso prostaglandin F 2α , an oxidative marker, were significantly associated with lower risk of cardiovascular disease (−4.5% risk for 10% higher paraoxonase, P <0.003; −5.3% risk for 10% higher 2,3 dinor‐8 iso prostaglandin F 2α , P =0.0092). In contrast, the oxidative markers myeloperoxidase and F 2α isoprostanes were not significantly associated with cardiovascular disease after adjustment for glycated hemoblobin. There were no significant differences between DCCT intensive and conventional treatment groups in the change in all biomarkers across time segments.

Conclusions

Heightened antioxidant activity (rather than diminished oxidative stress markers) is associated with lower cardiovascular disease risk in type 1 diabetes mellitus, but these biomarkers did not change over time with intensification of glycemic control.

Clinical Trial Registration

URL : https://www.clinicaltrials.gov . Unique identifiers: NCT 00360815 and NCT 00360893.

Nutrition Practice Guidelines for Type 1 Diabetes Mellitus positively affect dietitian practices and patient outcomes. The Diabetes Care and Education Dietetic Practice Group

OBJECTIVES

Assess the acceptance and ease of use of Nutrition Practice Guidelines for Type 1 Diabetes Mellitus by dietitians in a variety of settings; determine if nutrition care activities of dietitians change when practice guidelines are available; measure changes in patient control of blood glucose level, measured as glycated hemoglobin (HbA1c); compare patient satisfaction with care and perceptions about quality of life.

DESIGN

Using the approach of outcomes research, volunteer dietitians were recruited and assigned randomly to a usual care group or a practice guidelines group. Patients with type 1 diabetes were enrolled by dietitians and followed up for a 3-month period. Outcome measures included dietitian care activities, changes in patient HbA1c levels, and patient satisfaction and perceptions about quality of life.

SUBJECTS/SETTINGS

Dietitians from across the United States who responded to a recruitment notice participated. Their work settings included diabetes referral centers, endocrinology clinics, primary care and community health clinics, hospitals, and a worksite clinic. They recruited patients from their setting for the study. Outcome data were available from dietitians providing care to 24 patients using the new practice guidelines and dietitians providing care to 30 patients using more traditional methods.

STATISTICAL ANALYSIS

chi 2 Test, t test, and analysis of covariance.

RESULTS

Dietitians in the practice guidelines group spent 63% more time with patients and were more likely to do an assessment and discuss results with patients than dietitians in the usual care group. Practice guidelines dietitians paid greater attention to glycemic control goals. Levels of HbA1c improved at 3 months in 21 (88%) of practice guidelines patients compared with 16 (53%) of usual care patients. Practice guidelines patients achieved greater reductions in HbA1c level than usual care patients (-1.00 vs -0.33). This difference was statistically significant and clinically meaningful.

CONCLUSIONS/APPLICATIONS

Dietitians responded positively to practice guidelines for type 1 diabetes. Use of guidelines resulted in changes in dietitian practices and produced greater improvements in patient blood glucose outcomes at 3 months compared with usual care. Practice guidelines did not significantly influence patient satisfaction with care of perceived quality of life.

Treatment of early carcinoma of the vocal cords by radiotherapy

A total of 145 patients with early carcinoma of the vocal cords (T1,2N0) were treated by radiotherapy from 1979 to 1989. Survival and local control data were available for 135 and 127 patients, respectively. The respective 5 and 10 year results for overall survival were 75 and 68%. The 5 and 10 year probabilities of local control by radiotherapy were 89 and 86%, respectively, for T1 tumours and 70% at both time intervals for T2 tumours. Tumour recurrence following radiotherapy was documented in 18 of 127 patients. Tumour stage predicted significantly for local control, with recurrence rates for T1 and T2 tumours of 11 and 27%, respectively (P = 0.02). There was a higher proportion of recurrences for total radiation doses < or = 6200 cGy (17%) compared with > 6200 cGy (8%), but the difference was not statistically significant. Increasing duration of treatment was related significantly to increased recurrence for T2 (P = 0.01), but not T1, tumours. Most recurrences (60%) were salvaged successfully by laryngectomy. Three patients required laryngectomy for laryngeal oedema without recurrent tumour; all had been treated using a large field size (7 x 6 cm). There were 20 metachronous tumours, including five lung and two head and neck tumours. These results are similar to previous reports and confirm that radiotherapy is very effective for early glottic cancer, with high local control rates and effective salvage if local recurrences are recognized early.

Nutrition interventions for intensive therapy in the Diabetes Control and Complications Trial. The DCCT Research Group

As part of an intensive treatment regimen that had as its goal achieving and maintaining blood glucose levels in the normal range in individuals with insulin-dependent diabetes mellitus, dietitians in the Diabetes Control and Complications Trial implemented varying nutrition intervention strategies to counsel patients to attain normoglycemia. Dietary management encompassed recommendations on altering insulin dosages for varying food intake. Nutrition intervention was tailored to best meet a participant's life-style, motivation, ability to grasp information, diet history, and specific intensive insulin therapy. Dietitians were integral participants in the team management of individuals in the intensive treatment group. Selected nutrition interventions--Healthy Food Choices, exchange systems, carbohydrate counting, and total available glucose--and behavior management approaches were coupled with intensive insulin therapy. Case presentations illustrate each nutrition intervention in the attainment of normoglycemia.

Congenital absence of the vagina

Congenital absence of the vagina is the second leading cause of primary amenorrhea. Three patients had Mayer-Rokitansky-Küster-Hauser syndrome or congenital absence of the vagina. We discuss the clinical, diagnostic, psychosocial, and therapeutic features of these patients and the syndrome. The lack of diagnosis until after puberty of this syndrome in many patients demonstrates the need for more careful genital examination in prepubertal and pubertal girls.