Chapter 234: Osteoporosis and Osteopenia

PATIENT STORY

An 83-year-old woman accompanied by her 56-year-old daughter presents to the office with severe upper back pain over the past 2 days. Her medical problems include hypothyroidism, for which she is on replacement medication, and mild hypertension, which is controlled with a diuretic. She has known osteopenia and was taking calcium and vitamin D but had not tolerated a bisphosphonate. Physical examination reveals moderate thoracic kyphosis and tenderness over several lower thoracic vertebrae. A plain radiograph demonstrates vertebral compression fractures (Figure 234-1A). The daughter asks about management options for pain and prevention of future fractures and also about screening for herself. As there was a suggestion of multiple compression fractures, a CT was ordered to better visualize the fractures (Figure 234-1B).

INTRODUCTION

• Osteoporosis is a skeletal disorder characterized by low bone mineral density (BMD) ≤2.5 standard deviations (SD) of the mean for a gender-matched young white adult and compromised bone strength predisposing a person to fracture from minimal trauma.

• Osteopenia is defined as a BMD measurement of between 1.0 and 2.5 SD below the gender-matched young white adult mean. The World Health Organization also defines osteoporosis as a history of fragility fractures and osteopenia.¹

• The National Osteoporosis Foundation reported in 2014 that fewer than 25% of elderly women who had an osteoporotic fracture received a BMD study or medication to treat osteoporosis 6 months after the fracture, despite availability of cost-effective therapy.²

EPIDEMIOLOGY

• Approximately 12 million Americans older than age 50 years have osteopenia.³

• Half of all postmenopausal women will have an osteoporosis-related fracture in their lifetime; 25% will experience a vertebral deformity and 15% will suffer a hip fracture.³

• Low BMD at the femoral neck (T-score of -2.5 or below) is found in 21% of postmenopausal white women,16% of postmenopausal Mexican American women, and 10% of postmenopausal African-American women.

• About 1 in 5 older men are at risk of an osteoporosis-related fracture.³

• Vertebral fractures can cause severe pain and lead to 150,000 hospital admissions per year in the United States.

• Following a hip fracture, up to 20% of women die within 2 years and more than half are unable to return to independent living.⁴

ETIOLOGY AND PATHOPHYSIOLOGY

• Primary osteoporosis is a result of either aging changes or menopause.

  • Usually affects those older than age 70 years.

  • Proportionate loss of cortical and trabecular bone density ...