Long-term effects of lifestyle and metformin interventions in DPP on bone density.

In the Diabetes Prevention Program Outcome Study (DPPOS), a cohort at high risk of diabetes, randomization to intensive lifestyle intervention or metformin, both associated with weight loss, did not have long-term negative effects on BMD compared with the placebo group. Potential positive effects of metformin on bone warrant further investigation. INTRODUCTION: Randomization to lifestyle intervention (ILS) or metformin in the Diabetes Prevention Program (DPP) resulted in weight loss and reduced progression to diabetes. Weight loss is associated with reduced bone mineral density (BMD), but the long-term effects of these interventions on BMD are unknown. In the DPP Outcome Study (DPPOS), we determined if randomization to ILS or metformin, compared with placebo, was associated with differences in BMD approximately 16 years later. METHODS: Of 3234 DPP participants, 2779 continued in DPPOS and were offered ILS in group format. Those randomized to metformin were offered unmasked metformin. At DPPOS year 12, 1367 participants had dual-energy X-ray absorptiometry scans. BMD in metformin and ILS groups was compared to placebo using sex-specific linear regression models, adjusted for age, race/ethnicity, and weight and weight-bearing activity at DPP baseline. RESULTS: At DPPOS year 12, mean age was 66.5 (±9.5) years. Femoral neck BMD was similar in the ILS and placebo groups in men (difference = -0.021 g/cm2, 95%CI (-0.063, 0.021)) and in women (+0.014 g/cm2, 95%CI (-0.014, 0.042)). Femoral neck BMD was higher in the metformin compared to placebo group although not statistically different in men (+0.017 g/cm2, 95% CI (-0.023, 0.058)) and in women (+0.019 g/cm2, 95% CI (-0.009, 0.047)). Prevalence of osteoporosis was low and similar across treatment groups in men (0.9%; p=0.745) and women (2.4%; p=0.466). CONCLUSION: In a cohort at high risk of diabetes, lifestyle intervention or metformin did not appear to have long-term negative effects on BMD. Potential positive effects of metformin on bone warrant further research.

Relationship Between Hyperglycemia and Heart Transplant Rejection.

PURPOSE: Hyperglycemia increases risks of kidney and liver transplant rejection. To determine whether perioperative and subsequent glycemic control was associated with increased risk of heart transplant rejection over the year after transplantation, we performed a retrospective analysis of glycemic control and rejection rates in heart transplantation patients. METHODS: Perioperative glucose levels were analyzed in 157 patients undergoing transplantation at Northwestern Memorial Hospital from June 2005 to December 2012 and compared in patients with and without rejection found on routine follow-up biopsy specimens. RESULTS: Grade ≤1R rejection on biopsy was observed in 116 patients and grade ≥2R rejection (grade requiring increased anti-rejection treatment) in 41 patients. Although no significant differences in the preoperative fasting or inpatient mean glucose levels were found, the mean glucose levels from discharge to 1 year trended higher in those with grade ≥2R compared to grade ≤1R (128.8 ± 40.9 versus 142.2 ± 46.6 mg/dL, P = .084). In a multivariable logistic regression model, neither the lowest nor highest quartile of glucose levels had significantly different odds ratios (ORs) for the development of ≥2R compared to the middle 50% glucose levels. Older age (OR 0.96, P = .020) and higher body mass index levels (OR 0.86, P = .004) were significantly associated with lower odds of developing grade ≥2R. CONCLUSIONS: Although the glucose trend regarding rejection was not statistically significant, we cannot exclude the possibility that much higher glucose levels would influence rejection rates.