Do patients perceive a link between a fragility fracture and osteoporosis?
© Giangregorio et al; licensee BioMed Central Ltd. 2008
Received: 13 September 2007
Accepted: 21 March 2008
Published: 21 March 2008
To evaluate factors associated with whether patients associate their fracture with future fracture risk.
Fragility fracture patients participated in a telephone interview. Unadjusted odds ratios (OR, [95% CI]) were calculated to identify factors associated with whether patients associate their fracture with increased fracture risk or osteoporosis. Predictors identified in univariate analysis were entered into multivariable logistic regression models.
127 fragility fracture patients (82% female) participated in the study, mean (SD) age 67.5 (12.7) years. An osteoporosis diagnosis was reported in 56 (44%) participants, but only 17% thought their fracture was related to osteoporosis. Less than 50% perceived themselves at increased risk of fracture. The odds of an individual perceiving themselves at increased risk for fracture were higher for those that reported a diagnosis of osteoporosis (OR 22.91 [95%CI 7.45;70.44], p < 0.001), but the odds decreased with increasing age (0.95 [0.91;0.99], p<0.009). The only variable significantly associated with the perception that the fracture was related to osteoporosis was self-reported osteoporosis diagnosis (39.83 [8.15;194.71], p<0.001).
Many fragility fracture patients do not associate their fracture with osteoporosis. It is crucial for physicians to communicate to patients that an osteoporosis diagnosis, increasing age or a fragility fracture increases the risk for future fracture.
Osteoporosis has been described as a silent disease until an individual experiences a fragility fracture. A fragility fracture is a fracture that occurs with minimal trauma, such as a fall from a standing height or less. In Canada, age-adjusted incidence rates for hip fracture in 1993–4 were 479 per 100 000 for women and 187 per 100 000 for men, and have been projected to increase four-fold by 2041, and the annual cost of care were estimated at $650 million dollars in 2001 [1, 2]. Not only do fragility fractures impose an economic burden, but also there are human costs; fragility fractures can reduce quality of life, increase fear of falling, and often result in impaired mobility and a loss of independence [3–5]. Therapeutic options can reduce the number of new vertebral compression fractures by 40–60% within the first year in individuals with a fracture . For example, the relative risk of fracture associated with alendronate use compared with placebo in women with osteoporosis is 0.47 (95% confidence intervals 0.26–0.79) for hip fractures, 0.52 (0.42–0.66) for radiographic vertebral fractures and 0.70 (0.59–0.82) for all clinical fractures . Increasing age and a history of fragility fracture are independent predictors of subsequent fracture . Therefore, it is essential that individuals who experience fragility fracture be assessed and treated for osteoporosis. However, individuals over the age of 40 years with fragility fracture are not receiving appropriate osteoporosis management [9, 10].
If patients do not link their fractures with having a disease, and are not aware that they can actively participate in the disease evolution, then the opportunity to prevent future fractures may be lost . In-depth interviews reveal that many patients with fragility fracture had not associated their fracture with bone fragility. Instead they attributed their fractures to external factors, such as a fall, or slipping on ice [12–14]. In fact, for some patients the belief that their fracture was an accident was so strong that even subsequent fractures were attributed to external situations rather than bone fragility. A survey of peri- and postmenopausal women revealed that although the majority of women (89%) perceived osteoporosis a serious condition, only 29% thought they might be susceptible, and they were less concerned about osteoporosis when compared to cancer, even though the health consequences of osteoporosis are at least equal to that of breast cancer [12, 13, 15]. With a chronic disease such as osteoporosis, patient self-management is an important component to effective long-term management, especially with self-care issues such as adequate calcium and vitamin D intakes, fall prevention and exercise . There is also a need for long-term adherence to prescribed therapies and self-management. Therefore, it is essential that patients understand that having a fragility fracture increases their risk for subsequent fractures, and that preventative action may be necessary.
Although previous studies have evaluated whether peri- and postmenopausal women and women with fractures perceive their fracture to be related to osteoporosis [12, 13, 15], it is not known whether fragility fracture patients understand that they are at increased risk of future fracture. Further, no study has evaluated factors, such as age, gender or diagnosis of osteoporosis that may be associated with perceived susceptibility to subsequent fractures in fragility fracture patients. The purpose of the current study was to evaluate whether patients with a fragility fracture perceive themselves to be at risk of future fracture, and to identify factors associated with whether a fragility fracture patient perceives themselves to be at risk of future fractures.
A structured telephone interview was conducted with individuals who agreed to participate using a survey instrument developed and pilot-tested for this study by the research team. The interview contained questions about the following: socio-demographic information; prescription medication use in the past year (including treatments for osteoporosis, calcium and vitamin D supplementation); medical and fracture history; family history of osteoporosis; participation in osteoporosis preventative activities (e.g. exercise, intake of calcium rich foods, fall prevention); and participant perceptions about their risk of fracture.
To determine whether individuals who had had a fragility fracture understood what osteoporosis was, whether they associated their fractures with osteoporosis or perceived themselves at risk for future fracture, the following questions were included in the survey: 1) Do you think that breaking your (insert site of fracture here) means that you are at risk for breaking a bone in the future?; 2) Do you think your fracture was related to osteoporosis?; 3) Do you know what osteoporosis is?; and 4) If yes to question 3: What do you think it is?. Possible responses to questions 1–3 were "yes", "no" and "unsure". Question 4 was included to confirm whether their understanding of osteoporosis was accurate, and responses were qualitative in nature.
Descriptive statistics for demographic and clinical participant characteristics are presented as mean (standard deviation [SD]) for continuous variables or count (percent) for categorical variables. The sample size was based on building a stable multivariable model. Simulation studies demonstrate that logistic models require 10 to 15 events per predictor to produce stable estimates [18, 19]. We hypothesized that 40% of respondents would associate their current fracture with the potential for future fractures. Therefore, 125 respondents would be required to fit a model with 3–5 predictors. There were no missing data.
For the questions pertaining to perceptions of risk (questions 1 and 3 above), two separate analyses were performed; 1) the response "unsure" was coded as "no"; and 2) the response "unsure" was coded as missing. The following demographic and health-related variables were considered as potential correlates of patients' perceptions of risk: age, gender, education, marital status, living arrangements, site of index fracture, history of a previous fracture, family history of fracture at wrist, spine or hip after the age of 40, use of an assistive aid, ever being told they have osteoporosis, being on an osteoporosis medication, having experienced a loss of height and number of medications. Variables were selected for hypothesis-generating purposes.
Unadjusted odds ratios (OR) and 95% confidence intervals were calculated to identify factors associated with whether patients associated their fracture with being at risk of future fracture, or associated their fracture with osteoporosis. To be conservative, predictors found to be statistically significant at alpha = 0.20 in univariate analysis were entered into multivariable logistic regression models to identify factors that are associated with whether patients associate fragility fracture with and increased risk of future fracture, or with osteoporosis. When two variables that exhibited collinearity were both significant in univariate analyses, only one was included, and the one chosen was based on clinical relevance. We examined the residuals to assess model assumptions. Goodness-of-fit for the models was performed using the Hosmer-Lemeshow test . Data were managed and analyzed using SPSS® software (Version 15.0), and all statistical tests were two-sided. The criterion for statistical significance was set at alpha = 0.05.
Total Number of Participants
Age in years (SD)
Number of Females: n (%)
Menopausal Status (females): n (%)
Site of Index Fracture: n (%)
other femur fracture
Cause of fracture: n (%)
Fall from standing height
Slipping on ice
Fall from standing height while running
Hit it on something
Average time post-fracture in months (SD)
History of previous fracture: n (%)
Family history of fracture: n (%)
Self-reported height loss: n (%)
At least one fall in the past year*: n (%)
3 or more falls in the past year: n (%)
Use assistive aid for mobility (cane, crutches, walker, wheelchair): n (%)
4 or more prescription medications: n (%)
Average number of prescription medications: Mean (SD)
Marital Status: n (%)
Living arrangements: n (%)
Live with others
Perceptions of osteoporosis and fracture risk
Responses of individuals who have had a fragility fracture to questions about their perceptions of osteoporosis and fracture risk (n = 127)
Response: Number of Respondents (%)
Do you think that breaking your (insert fracture site) means that you are at increased risk of breaking a bone in the future?
Do you think your fracture was related to osteoporosis?
Have you ever been told that you have osteoporosis?
Do you know what osteoporosis is?
Logistic Regression Analysis Results
Estimated odds ratios (95% CIs) for variables associated with perceiving that a fragility fracture results in an increased risk of future fracture, or that the fragility fracture is related to osteoporosis.
OR (95% C.I.)
Do you think that breaking your (insert fracture site) means that you are at increased risk of breaking a bone in the future? (unsure coded as missing, n = 108)
Ever told you have osteoporosis (No)
22.91 (7.45; 70.44)
Age (per year)
Do you think that breaking your (insert fracture site) means that you are at increased risk of breaking a bone in the future? (unsure coded as no, n = 127)
Ever told you have osteoporosis (No)
Age (per year)
Do you think that your fracture was related to osteoporosis? (unsure coded as missing, n = 90)
Ever told you have osteoporosis (No)
Use an assistive aid (No)
Do you think that your fracture was related to osteoporosis? (unsure coded as no, n = 127)
Ever told you have osteoporosis (No)
Use an assistive aid (No)
The current study demonstrates that a substantial number of individuals who suffer a fragility fracture do not perceive themselves to be at increased risk for future fracture, and an even greater number of individuals do not associate their fracture with osteoporosis. The odds that individuals perceived themselves at risk for future fracture were higher among individuals who had been told that they had osteoporosis, but decreased with increasing age. If individuals with fragility fracture do not perceive themselves at risk for future fracture, they may be less likely to accept or adhere to recommended treatment [11, 21], which may partially explain the reports of poor management among this patient group. Recent systematic reviews have demonstrated that in Canada and internationally, individuals who suffer fragility fractures are not receiving adequate osteoporosis management [9, 10].
Perceived susceptibility to osteoporosis has been evaluated among community-based women over the age of 40 who had not been diagnosed with osteoporosis; the majority of women perceive their risk to be lower than other women their age, and they attributed their lower risk primarily to their own preventative behaviours . The current study is unique because it evaluated perceived risk of fracture among community-living individuals who had recently suffered a fragility fracture and are therefore at higher risk of future fracture than individuals who have not had a fracture. However, even among this higher risk group, many individuals with a prior fragility fracture still do not perceive an increased susceptibility to future fracture. Perceived risk of future fracture decreased with increasing age among fragility fracture patients, which is alarming considering that increasing age and a history of fracture are both independent predictors of subsequent fracture . Further, it has been demonstrated that older individuals with fragility fracture are not prescribed osteoporosis treatment as often as younger individuals . A negative relationship between perceived risk of chronic diseases (i.e. osteoporosis, breast cancer and heart disease) and age has been demonstrated previously among community-living individuals [23, 24]. It has been suggested that women may perceive themselves to be less susceptible to osteoporosis with age because the longer they live without experiencing the disease, the more distant the threat of the disease appears, the more likely they are to perceive the disease occurrence to be low, or the more dissimilar they view themselves to women with the disease . However, the participants in the current study have already experienced a consequence of osteoporosis, namely, a fragility fracture. It appears many individuals do not recognize their fracture is an indicator that they are at risk for osteoporosis and future fractures. Therefore, it is crucial to communicate to individuals who have suffered a fragility fracture that they may have osteoporosis and are at increased risk of future fractures .
The likelihood that a patient with a fragility fracture perceived themselves to be at increased risk of future fracture was much greater if they had been told that they had osteoporosis. However, the clear communication of an osteoporosis diagnosis to fragility fracture patients is inconsistent, and there is a care gap between the occurrence of a fragility fracture and osteoporosis diagnosis and treatment [9, 10, 25]. Interestingly, the current study demonstrated that only about one in five individuals thought their fracture was related to osteoporosis. This is particularly concerning considering that almost half of the sample had been given a diagnosis of osteoporosis, and 80% of those were diagnosed before the index fracture. The results of the current study suggest that patients may not understand that osteoporosis leads to an increased risk of future fracture, that there is a lack of understanding of what osteoporosis is, or that patients do not associate having a fragility fracture with having a chronic disease, namely osteoporosis.
A recent study demonstrated that perceived susceptibility to osteoporosis was related to current use of antiresorptive medication . Similarly, that having a previous bone density test or diagnosis of osteoporosis were the only factors associated with active consideration of or current use of osteoporosis medication in hip fracture patients . Therefore, communicating to patients that having a fragility fracture increases their susceptibility to future fracture may be crucial for increasing the probability that patients will accept osteoporosis therapy and participate in chronic disease management. It has been demonstrated that if women had an understanding of the impact of a self-management behaviour (i.e. calcium intake) related to osteoporosis they were more likely to act on that knowledge . Self-management is an important component of chronic disease management; a recent meta-analysis revealed that self-management programs for diabetes mellitus and hypertension produced statistically and clinically significant benefits . A patient-centred approach targeting the patient's perception of future fracture risk may be a critical element in improving osteoporosis management. In a prospective study, providing women with a decision aid about benefits and risks of hormone therapy, educational tools and feedback about densitometry resulted in increased use of osteoporosis medications, including calcium and vitamin D . A recent quasi-experimental non-randomized trial demonstrated that patient education in addition to informing the physician of the fracture and providing treatment guidelines significantly improved both osteoporosis investigation and treatment rates, resulted in improved persistence with therapy and was cost-saving [29, 30]. Further, the method of communication may be crucial. For example, a recent study demonstrated that patients preferred simple bar charts with absolute lifetime risk depicted on them .
The current study has a few limitations. Among the potential pool of participants, 42% chose not to participate and 30% could not be contacted to determine if they were eligible. We do not have bone density data to confirm whether all participants have osteoporosis. However, having a fragility fracture is a predictor of future fractures independent of bone density . We report history of prior fracture after the age of 40, but we did not ascertain whether prior fractures were also fragility fractures. The proportion of respondents reporting a diagnosis of osteoporosis is relatively high compared to previous reports of the proportion of fragility fracture patients diagnosed with osteoporosis after fracture [9, 10], suggesting that we may have over-represented individuals with diagnosed osteoporosis. However, even among our sample there were a substantial number of individuals who did not make the link between their fragility fracture and osteoporosis. Given the observed relationship between having an osteoporosis diagnosis and perception of future fracture risk in the current sample, inclusion of a more representative sample may have actually increased the strength of our findings.
In summary, many individuals who suffer fragility fracture do not associate their fracture with osteoporosis. Communicating a diagnosis of osteoporosis to the patient was strongly related to perceptions of future fracture risk, as was age. It is crucial for health care providers to communicate to the patient that increasing age and having a fragility fracture increases the risk for future fracture, so that patients can become active participants in chronic disease management. It may also be necessary to rethink the way we convey messages about fracture risk to patients; rather than relying on brief verbal communications between patient and physician during follow-up visits, the message could be emphasized using well designed written materials that include attention-grabbing graphics. As well the message that fragility fracture equals risk of future fragility fracture needs to become part of a nationwide post-fracture care initiative that targets patients in hospital so that all patients are made aware of the risk. Future research should investigate whether risk perceptions or a diagnosis of osteoporosis influences acceptance of or adherence to recommended therapies, or the impact of patient-centred educational interventions on the patient's perception of risk.
The authors would like to acknowledge financial support from The Drummond Foundation. A. Cranney holds a research salary award from the Canadian Institutes of Health Research. J.D. Adachi holds the Alliance for Better Bone Health Chair in Rheumatology, funded by the Alliance of Procter & Gamble and Sanofi Aventis. The authors had full access to all of the data in the study and take responsibility for the integrity of the data and the accuracy of the data analysis. This project was part of the "Fracture? Think Osteoporosis!" initiative at Hamilton Health Sciences. We would like to thank the orthopaedic surgeons at the Henderson Hospital and St. Joseph's Healthcare for their assistance: Dr. Mitchell Winemaker, Dr. David Wismer, Dr. Nigel Colterjohn, Dr. Brett Dunlop, Dr. Jaydeep Moro and Dr. Arthur Porte. We also acknowledge the assistance of Madeline Nixon, Jennifer Ranford, Ruth McCallum, and Katherine Gaebel in the recruitment, screening and interviewing of study participants.
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