Secondary fracture prevention with osteoporosis medication after a fragility fracture in Sweden remains low despite new guidelines

Osteoporosis is a public health problem and a major cause of disability-adjusted life years (DALYs) [1]. Fragility fractures in older adults are the most severe consequence of osteoporosis and affect one in two women and one in four men in Sweden and the burden is increasing in Europe, Asia, and the USA [2‐5]. Fragility fractures are associated with severe costs for both patients and society [6]. To counteract suffering and costs, secondary prevention after a fragility fracture is recommended. Such pharmacological secondary fracture prevention has proven to be effective in slowing bone loss and decreasing the risk of new fractures [7]. The most common medications are bisphosphonates, shown to reduce vertebral fractures by 40–70% and hip fractures by 40–50% [8]. In Sweden, like in many other countries, there are national guidelines for how osteoporosis medication should be prescribed. These guidelines state that all postmenopausal women and all men over 50 years old who experience a fragility fracture should be considered for intervention with osteoporosis medication to prevent further fractures [9]. For more severe fractures (e.g., hip fracture and vertebrae fracture), medications could be prescribed without further evaluation. However, despite clear guidelines, undertreatment continues to be an issue [2, 10].

Estimated osteoporosis prevalence in Sweden for adults aged 50 and older was 22% among women and 7% among men [11]. However, due to a lack of screening and inconsistencies in bone mineral density (BMD) management programs, it is difficult to estimate the true prevalence of osteoporosis in the population and the observed proportion is likely underestimated. As an example, a Swedish study found that only 22% of older women eligible for osteoporosis treatment according to national guidelines received medical treatment [12]. IOF estimates the treatment gap (individuals with osteoporosis without medical treatment) to be 67% in 2021 [11]. The gap is likely greater among men than among women because osteoporosis is less often considered a diagnosis among men, even among those who have had a fracture, who are thus less often considered for medical treatment [13‐15].

While several studies suggest undertreatment of osteoporosis after a fragility fracture, population-wide assessments are still scarce. Moreover, knowledge regarding if and how osteoporosis medication is prescribed to a similar extent in population subgroups is needed. If we can, for example, identify groups where the prescription proportion is lower than in other groups, preventive strategies can be directed. Therefore, with this study, we aimed to investigate and describe secondary fracture prevention with medical osteoporosis treatment among the older Swedish population. In the absence of a population measure for osteoporosis, we use a fragility fracture (fracture of the vertebrae, hip, wrist, or humerus) caused by low-energy trauma as a proxy, given that such fractures in older adults are most often associated with osteoporosis [16]. We specifically examine how prescription has changed over time and difference between men and women, age groups, and education level.

In 2020, 8.5%, 15.3%, and 25.5% of women aged 70–79, 80–89, and 90 + had a fragility fracture. Among men, aged 70–79, 80–89, and 90 + , 3.4%, 7.0%, and 14.0% experienced a fragility fracture. Although the absolute number of fragility fractures has increased over the study period because of a growing and aging population, the proportions of persons with a fragility fracture have remained stable over time (see Appendix table 1). Table 2 shows the sociodemographic characteristics of the study population that had endured a fragility fracture in the last 5 years between the years 2007 and 2020.

The aim of this study was to investigate and describe how pharmacological osteoporosis treatment is prescribed following a fragility fracture in the older Swedish population. We used high-quality register data from all Swedish residents aged 70 years and older who had experienced a fragility fracture, with information about all their prescriptions extracted from pharmacies. Our results show that even though prescriptions of osteoporosis medications have increased over time, it is still at rather low levels in a population with a clear indication for treatment of osteoporosis. The proportion of men with osteoporosis prescriptions is especially low although doubled between 2007 and 2020. For women, the increase over time is more modest. The proportion of people with higher education with osteoporosis prescriptions was higher than the proportion of people with lower education; this difference was greatest at the beginning of the study period, but this gap has closed in recent years. A difference in prescription proportion between high- and lower-educated women has also been shown by Wastesson et al. who investigated differences in osteoporosis medication between educational levels with data from 2005 [18]. The slight decrease in medication proportion for highly educated women in the most recent years is surprising but might be due to changes in the population composition over the study period (e.g., higher education became more common during the study period).

When additionally considering other medications with known bone positive agents (although limited effect), such as vitamin D, calcium, and estrogen, it was clear that supplementation with only vitamin D and/or calcium is the most common bone health-related treatment both before and after a fragility fracture. The current Swedish guidelines state that vitamin D and calcium can be given as a complement to osteoporosis medication, if an insufficiency exists, but not as the only treatment for osteoporosis. Our results show that it is still more common to get only vitamin D and calcium after a fragility fracture than to receive the recommended specific osteoporosis treatment, contrary to current guidelines.

The reasons for the low prescription proportions are likely several. Undertreatment due to lack of knowledge about the balance between side effects and benefit for the oldest frail population is one possible explanation. Individuals 90 years old and older have the lowest proportions of prescriptions, which is both expected and worrying. Some regions in Sweden advise against prescribing osteoporosis medication to very frail older adults that are not expected to live long enough to see the benefit of it. Meanwhile, we know that it is now more common to live an active life at older ages, and for these individuals, the stress that an osteoporotic fracture imposes might be a tipping point into frailty or an accelerated declining health and quality of life. In addition, the risk of recurrent fractures is high, which increases the cost for society and the suffering for the individual even more [19, 20]. It is therefore important to consider not only a patient’s chronological age but also health status when deciding their medical osteoporosis treatment. Medical contraindications to prescribe, such as renal insufficiency, can be one reason contributing to the low prescription proportions [21]. There is a risk that clinicians avoid prescribing to the oldest old due to a sparsity of studies in this group, but also believe that the risks outweigh the benefits for vulnerable individuals. A study performed in Swedish health care has shown that Fracture Liaison Services (FLS) regimes, as a part of post-fracture care, could decrease the treatment gap for osteoporosis [22], with 32% of fracture patients getting treatment after a FLS implementation compared to 13% prior to FLS. FLS implemented in two Swedish hospitals also reduced recurrent fracture risk with 18% [23]. However, although the awareness and use of such programs are increasing, there is still a need to implement and cohere to FLS regimes [24]. Both studies were, however, small samples conducted in only one or two centers. Kanis et al. report that 25% of all hospitals in Sweden report to be using/have established FLS, to be compared with the UK and the Netherlands that have a 50% coverage of hospitals with FLS [25]. The same report concludes that the Swedish national guidelines are clear and of high quality. However, different specialists can be responsible for the FLS in different regions and hospitals, and several different types of FLS exist [25]. Sweden has special geographic and socio-economic conditions that can affect regional differences, the northern parts of the country are sparsely populated while the southern parts more densely populated, and the physician/habitant rate is also lower in the northern parts. In addition, health care is organized within politically governed regional organizations which strive to promote and strengthen local self-government. Despite this, the national guidelines about evaluation and treatment from the Department of Health and Welfare and the Medical Products Agency are supposed to be implemented on a national level. These regional differences might partly explain the low prescription proportion among individuals with a previous fragility fracture. Our results indicate that improving the coordination of FLS regimes in Sweden, according to existing national guidelines, should be a prioritized action. Although regional differences in Sweden were outside the scope of this study, mapping regional differences to be able to lift regions that do not use FLS should be prioritized and a subject of future studies.

Another possible reason for the overall low prescription proportion is underdiagnosis. Despite clear guidelines, there seems to be a low frequency of screening among older fracture patients due to unclear BMD testing regimes and a lack of DXA scan machines in some parts of Sweden [26]. Targeted screening is recommended while general screening is not. However, the most recent guidelines state that medical treatment should be prescribed without further investigation for hip and vertebrae low-energy fractures [9, 27]. We show that osteoporosis in men with a fragility fracture seems to be even more undertreated than that in women, in line with previous studies [13, 14]. This might be because osteoporosis is typically considered a women’s disease and men with fragility fractures might not be evaluated to the same extent as women. According to Vescini et al., men experience fractures about 10 years later than women do, which might imply that they have more comorbidities and higher frailty levels, and thus worse outcomes after the fracture than women [13]. This could also impact the chance of being prescribed osteoporotic medication. Studies have shown that FLS are effective to mitigate inequity in osteoporosis medication, benefitting men and the oldest old [28, 29].

Our findings suggest that medical treatment after fragility fractures in Sweden does not adhere to recommendations and national guidelines. However, to clarify the level of undertreatment, we would need more detailed information on drugs prescribed within health care, per requisition. Our analyses on aggregated requisition data show that it is becoming more common in Sweden to distribute some drugs as requisition, among them injections of bisphosphonates or denosumab. However, comparison with the aggregated data should be made with caution because these numbers are based on all Swedes regardless of prior fracture or age. Moreover, some of the medications might be prescribed for other indications, such as treating hypercalcemia in cancer patients [30]. This means that the proportion shown in the appendix material is an overestimation with regard to osteoporosis medication administered through requisition. Denmark has a similar system as Sweden in terms of medications per requisition and a recent study has shown a pattern similar to our findings [31]. This might indicate that the increase in medications per requisition could explain the plateau effect that we see in prescribed medications in the recent years. It is also possible that part of the prescriptions of only vitamin D and calcium might be accompanied by osteoporosis medications on requisition, in accordance with guidelines. However, even when including the proportion of medications given on requisition, the total medical treatment of osteoporosis still appears low.

Even if prescribed osteoporosis medications among fragility fracture patients have increased in the last decades, undertreatment persists despite clear national guidelines. Younger age groups, women, and people cohabiting with someone else have higher odds of osteoporosis prescription after a fragility fracture throughout the study period. Education level was only marginally associated with prescriptions, and only among women. Vitamin D and calcium are more commonly prescribed than specific osteoporosis medications, contrary to what the current guidelines recommend.