Are There Differences Between Men and Women Prescribed Bisphosphonate Therapy in Canadian Subspecialty Osteoporosis Practices?

ANNA M. SAWKA, JONATHAN D. ADACHI, ALEXANDRA PAPAIOANNOU, LEHANA THABANE, GEORGE IOANNIDIS, K. SHAWN DAVISON, WOJCIECH P. OLSZYNSKI, JACQUES P. BROWN, DAVID A. HANLEY, TIM M. MURRAY, ROBERT G. JOSSE, ROLF J. SEBALDT, ANNIE PETRIE, ALAN TENENHOUSE, and CHARLES H. GOLDSMITH

ABSTRACT.

Objective. To determine if there are differences between men and women referred for treatment of osteoporosis in Canada.

Methods. We performed an observational study of 1588 patients (163 men, 1425 women), 50 years of age and older, who were prescribed cyclic etidronate or alendronate for treatment of osteoporosis or osteopenia and had at least 2 years of followup registered in the Canadian Database for Osteoporosis and Osteopenia Patients (CANDOO). Comparisons of characteristics between men and women were performed using Pearson chi-square test, Student's t test, or a Kruskal-Wallis test, whichever was most appropriate.

Results. Mean baseline femoral neck and lumbar spine bone mineral densities were significantly higher in men than women at both the femoral neck and lumbar spine (p < 0.05, respectively). Men had double the rate of prevalent vertebral fractures (44%, 72/163) compared to women (22%, 315/1425; p < 0.001) and triple the rate of multiple prevalent vertebral fractures (10%, 17/163) compared to women (3%, 37/1425, p < 0.001). Furthermore, men were twice as likely as women to sustain a fracture within 2 years of starting treatment during observation in the CANDOO study (men: 4%, 7/163, women: 2%, 24/1425, p = 0.033).

Conclusion. Osteoporosis may be under-recognized in men until the condition is at an advanced stage. A form of gender bias may exist in recognition and treatment (or referral for treatment) of osteoporosis in men. (J Rheumatol 2004;31:1993-5)

Key Indexing Terms:

OSTEOPOROSIS
FRACTURES
GENDER
DIPHOSPHONATES

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The CANDOO database has been sponsored in part by Procter and Gamble Pharmaceuticals.

From McMaster University, St. Joseph's Healthcare, Centre for Evaluation of Medicines, Hamilton, and the University of Toronto, Toronto, Ontario; the University of Saskatchewan, Saskatoon, Saskatchewan; Centre Hospitalier de Laval, and McGill University, Montreal, Quebec; and the University of Calgary, Calgary, Alberta, Canada.

A.M. Sawka, MD; J.D. Adachi, MD; A. Papaioannou, MD; L. Thabane, PhD, McMaster University, St. Joseph's Healthcare, Centre for Evaluation of Medicines; G. Ioannidis, MSc, St. Joseph's Healthcare; K.S. Davison, PhD, McMaster University; W.P. Olszynski, MD, University of Saskatchewan; J.P. Brown, MD, Centre Hospitalier de Laval; D.A. Hanley, MD, University of Calgary; T.M. Murray, MD; R.G. Josse, MD, University of Toronto; R.J. Sebaldt, MD; A. Petrie, McMaster University, St. Joseph's Healthcare; A. Tenenhouse, MD, McGill University; C.H. Goldsmith, PhD, McMaster University, St. Joseph's Healthcare, Centre for Evaluation of Medicines.

Address reprint requests to Dr. J.D. Adachi, 501-25 Charlton Avenue East, Hamilton, Ontario, L8N 1Y2.

Submitted December 1, 2003; revision accepted April 28, 2004.

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