Transdermal Nitroglycerin Therapy May Not Prevent Early Postmenopausal Bone Loss.

J Clin Endocrinol Metab. 2009 Jun 23; Wimalawansa SJ, Grimes JP, Wilson AC, Hoover DR, Context: Osteoporosis is common among postmenopausal women; pilot studies support the concept of nitric oxide (NO) donors reducing bone mineral density loss. Objective: Evaluate if NO donor, nitroglycerin prevents postmenopausal bone loss. Design: Three-year randomized, blinded, single-center, placebo-controlled clinical trial. Setting: Single-center study at the University of Medicine and Dentistry - Robert Wood Johnson Medical School, New Brunswick, New Jersey. Participants: 186 postmenopausal women aged 40 to 65 years, with lumbar bone mineral density (BMD) T-scores of 0 to -2.5. Intervention: Women, stratified by lumbar T-score (< -1.50 and >/= -1.50) and years since menopause (5 years), were randomized to receive, i) nitroglycerin ointment (22.5 mg as Nitrobid(R), or ii) placebo ointment receiving daily for three years. Both groups took 630 mg daily calcium plus 400 IU vitamin D supplements. Measurements: Bone mineral density (BMD) was measured at 6 months and annually by dual energy x-ray absorptiometry. Percent change in lumbar vertebrae BMD was the primary outcome. Hip BMD, total body bone mineral content and height were secondary outcomes. Results: After 36 months of therapy, changes of -2.1% in the active group (n=88) and -2.5% in the placebo group (n=82) in lumbar spine BMD were seen; p = 0.59 (95% CI -1.001, 1.975). Secondary outcomes also did not differ by intervention arm. The active group reported more headaches compared to the placebo group (57% vs. 14%, p