Comparison of safety outcomes among Caucasian, Hispanic, Black, and Asian patients in duloxetine studies of chronic painful conditions.

OBJECTIVE: This post-hoc analysis was conducted to investigate if safety outcomes differed among race/ethnic subgroups of patients treated with duloxetine for chronic painful conditions. RESEARCH DESIGN AND METHODS: Pooled data from 15 placebo-controlled clinical trials were used to compare the safety outcomes of duloxetine among patients of Caucasian, Hispanic, Asian, and Black race/ethnic origins. Patients were randomized to receive placebo (n = 2199) or duloxetine (n = 3148) for treatment of diabetic peripheral neuropathic pain, fibromyalgia, osteoarthritis pain, or chronic low back pain. For categorical outcomes such as study discontinuation, adverse events leading to discontinuation, and treatment-emergent adverse events, incidence rates were summarized by race/ethnic subgroups. The Breslow-Day test was used to assess the homogeneity of treatment odds ratios across the four subgroups. For continuous outcomes such as changes in vital signs, body weight, and laboratory measures, an analysis of covariance or analysis of variance model was used and duloxetine effects were compared among race/ethnic subgroups based on the test of treatment-by-subgroup interaction. RESULTS: No significant differences were found among race/ethnic subgroups for discontinuation due to adverse events except for anxiety (p = 0.040). Rates of nausea and decreased appetite were significantly higher (p ≤ 0.05) in duloxetine-treated patients compared with placebo-treated patients within each race/ethnic subgroup. The Breslow-Day test was not significant for most safety outcomes, nor were treatment-by-race/ethnic subgroup interactions (p > 0.1), which suggested duloxetine effects were not significantly different among race/ethnic subgroups. CONCLUSION: Overall, these results detected only minimal differences among safety outcomes assessed in these race/ethnic subgroups in patients treated with duloxetine for chronic painful conditions. The unbalanced sample sizes among the race/ethnic subgroups may have limited the power to detect treatment by race subgroup interactions. These post-hoc subgroup analyses were of an exploratory nature and the results should be interpreted with appropriate caution.

Effect of a blueberry nutritional supplement on macronutrients, food group intake, and plasma vitamin E and vitamin C in US athletes.

Antioxidants from a blueberry beverage may impact plasma vitamins. We examined vitamins/food selection in 12 college athletes during 30 days compared with placebo. Blood was collected before and after exercise at the beginning of the study (day 1) and then after a 30-day period of taking a daily supplemental beverage (day 30). The six trials involved blood that was drawn pre-beverage ingestion/pre-exercise (trials 1 and 4), post-beverage ingestion/pre-exercise (trials 2 and 5), and post-beverage ingestion/1 h post-exercise (trials 3 and 6), on day 1 (trials 1, 2, and 3) and day 30 (trials 4, 5, and 6). Analysis of variance revealed non-significant differences for macronutrient or gamma-tocopherol and vitamin C intakes by food frequency questionnaire or plasma vitamins by liquid chromatography. There was a trend (P = 0.083) in the group x time interaction for alpha-tocopherol intake by repeated-measures analysis of variance. Blueberry alpha-tocopherol (23.91 +/- 9.31 mg) was significantly (P < 0.05) higher than placebo alpha-tocopherol intake (7.59 +/- 0.95 mg) on day 1, but not on day 30 (blueberry, alpha-tocopherol = 9.04 +/- 2.35 mg, placebo, alpha-tocopherol = 11.46 +/- 3.65 mg) by pairwise comparisons. Blueberry supplementation did not affect plasma vitamin concentrations or gamma-tocopherol and vitamin C intakes, and may reduce alpha-tocopherol intake in those starting with a higher alpha-tocopherol intake, yet not altering athletes' eating habits.