Discussion
The main objectives of this epidemiological study were to identify the clinical profile of Spanish postmenopausal women with a diagnosis of osteoporosis and to establish possible associations between women with osteoporosis and the presence of risk factors for other conditions. The data clearly show that, in addition to the increased risk of bone fractures, women with osteoporosis are also at risk for endometrial pathology, breast cancer, and cardiovascular disease.
As expected in an osteoporotic population, almost half of the study participants had at least one risk factor for bone fractures (in addition to being postmenopausal and having a T-score <-2.5, as measured by DXA). Moreover, at least one risk factor for breast cancer and at least one risk factor for cardiovascular disease were identified in 96.8% and 83.4% of participants, respectively. When the magnitude of risk was assessed, 20.1% of women presented with a high cardiovascular risk (three or more risk factors), 16.6% were at high risk for bone fractures (two or more risk factors, in addition to being postmenopausal and having a T-score <-2.5), and 14.5% were at high risk for developing breast cancer in the next 5 years, whereas less than 10% were identified as having a high endometrial risk. Although each of these conditions share a number of risk factors with osteoporosis (such as age, BMI, smoking status, and other lifestyle choices), it remains to be seen whether each of these conditions is linked with osteoporosis, or indeed with each other, by common pathophysiological mechanisms.
Both pharmacological and nonpharmacological treatments/interventions for osteoporosis were used by most women in the study. Furthermore, use of pharmacological and nonpharmacological treatments was evenly matched among the high-risk groups for bone fractures, endometrial pathology, and breast cancer. Bisphosphonates and selective estrogen receptor modulators were used by around 50% and 40% of those using pharmacological treatment, respectively. Because these women were under the care of a gynecologist and were aware of their osteoporosis, it is not surprising that most of them were being treated for the condition. Treatment utilization among the general population of postmenopausal women with osteoporosis will not be as high because a large proportion of women will remain undiagnosed. Of note, a significantly higher proportion of participants with a high risk for bone fractures were receiving pharmacological and/or nonpharmacological osteoporosis treatment, compared with those who had one or no risk factors (P < 0.01). Again, it is possible that high-risk women had been advised by their prescribing gynecologist to use these treatments or interventions. However, regardless of individual clinical risk stratifications across the high-risk groups (ie, whether women were at high risk for bone fractures, endometrial pathology, or breast cancer), the proportion of women treated and/or the type of treatment they received seemed comparable.
The epidemiology of osteoporotic bone fractures has been reviewed in the literature. In agreement with the current study, risk factors for bone fractures were identified as follows: female sex, estrogen deficiency associated with the postmenopausal period, young age at menarche, previous fractures, family history of fractures, cigarette smoking, excessive alcohol consumption, and low BMI. Moreover, these risk factors have been commonly observed among postmenopausal women with osteopenia or osteoporosis, as shown in previous epidemiological studies using an approach similar to that of the current study (ie, interviews or questionnaires). To our knowledge, no prior epidemiology studies have investigated the presence of risk factors for bone fractures, endometrial pathology, breast cancer, and cardiovascular disease in postmenopausal women with osteopenia and osteoporosis. Nevertheless, in line with the current findings, earlier studies have identified possible associations between osteoporosis and other conditions (such as rheumatoid arthritis, breast cancer, and cardiovascular disease) in perimenopausal and postmenopausal women.
The sample of women in this study, which included a broad range of medical characteristics and sociodemographics, was generally representative of Spanish postmenopausal women with osteoporosis who are visiting their gynecologist. Gynecologists were chosen as the recruiters for this study because they are the primary point of care for Spanish women seeking health checks or treatment of perimenopausal and postmenopausal symptoms or conditions. However, as with any study where participants are voluntarily seeking treatment from a healthcare provider, there will be an inherent bias in the sample, and this constitutes one of the limitations of this study. Women in this study will have received advice from their gynecologist regarding treatments and lifestyle interventions, such as diet, exercise, smoking, and alcohol intake, all of which may have altered the prevalence of risk factors for the other conditions investigated, including endometrial pathology, breast cancer, and cardiovascular disease. Furthermore, because these women were seeking advice from their gynecologist, it is possible that they may be more health-conscious and treatment-compliant than the general population they are intended to represent. In addition, another limitation of this study is that self-reporting questionnaires are often subject to underreporting and recall bias, particularly with respect to topics such as lifestyle choices and family history. An example of this is the proportion of participants (66.6%) who reported to have never smoked cigarettes, which is much higher than expected for this population.
Of note, among women who underwent BMD scans during the study visit, around 20% were deemed to be nonosteoporotic (ie, they had a T-score >-2.5). These women had been diagnosed with osteoporosis within the last 2 years (as per inclusion criteria) and had received treatment and advice under the care of their gynecologist, which subsequently led to a reversal of their osteoporosis.
A comprehensive WHO initiative has led to the development of an online fracture risk assessment tool (FRAX tool) that enables physicians to estimate the individual risk of fracture for a particular individual. Although the FRAX tool is country-specific, the Spanish version is not yet widely used among practicing gynecologists in Spain because several studies have shown that it underestimates the risk of major osteoporotic fractures by nearly 50% and that it shows poor discriminative and predictive capacity overall.
Although previous data have described a possible association between osteoporosis and breast cancer and cardiovascular disease, data from this study have highlighted the coexistence of risk factors for these conditions (and, additionally, endometrial pathology) in postmenopausal women who have recently been diagnosed with osteoporosis. Because many of the cardiovascular risk factors are modifiable (such as BMI, smoking, and diet), healthcare providers should use the time of diagnosis and treatment of postmenopausal osteoporosis as opportunities to also advise women on measures that can be taken to prevent cardiovascular outcomes. Although most of the identified risk factors for breast and endometrial cancer are nonmodifiable, healthcare providers caring for perimenopausal and postmenopausal women should remain diligent in assessing any possible risk factors for these conditions when treating women for osteoporosis to ensure that the most suitable pharmacological and nonpharmacological interventions are chosen. Equally, the bone health of women receiving treatment for endometrial pathology, breast cancer, or cardiovascular disease should be carefully monitored. During the transition through menopause, women should be encouraged to have regular and frequent health checks and to adopt a healthy lifestyle to reduce the risk of future illnesses.