( PDF ) Rev Osteoporos Metab Miner. 2010; 2 (3) suplemento: 8-11

Nogués Solán X, Guerri R, Solé E, Díez-Pérez A
URFOA (Unitat de Recerca en Fisiopatologia Ossia i Articular) – Institut Municipal d’Investigació Mèdica – RETICEF – Departamento de Medicina Interna Hospital del Mar – Universitat Autónoma de Barcelona

 

Introduction

Osteoporosis (OP) is included in the group of diseases which constitute the greatest health problems in the world, both for its ubiquity and for its socioeconomic consequences. In the United States of America it has been calculated that around 10 million people have OP and that nearly 34 million are at risk of suffering a fracture due to their having low bone mass1. In Spain, it is estimated that 3 million people suffer from OP and that this would mean an incidence of hip fracture of approximately 6.94 ± 0.44 per 1,000 inhabitants per year2. However, it is difficult to know exactly the global reach of OP since only data on femoral fractures is known with any exactitude, because it is the only one which always requires hospitalisation. In fact it would be possible to divide the consequences of OP into three well differentiated types of fracture: vertebral fracture (VF), femoral fracture (FF) and non-vertebral, non-hip fracture (NVF). VF has the inconvenience that it is only symptomatic in 30% of cases, and despite a third of vertebral fractures requiring specific medical attention, the rest are underestimated and remain diagnosed as back pain or arthritic lumbago3. FFs are the only truly quantifiable of these fractures, since they always require hospitalisation, at least in countries described as developed, and their costs can be assessed with greater accuracy. NVFs, which would include fractures of the forearm, humerus, clavicle, ribs, and ankle, are also very difficult to quantify, since although some cases require surgical intervention, the majority are attended to in outpatients or casualty departments of hospitals without the patient being admitted.

Vertebral fractures
Epidemiological studies such as the European Vertebral Osteoporosis Survey (EVOS)4 have allowed, through the systematic taking of X-rays, the realisation of an approximation of the true picture of this condition in Europe and in our country (Table 1). Naves et al.5 published the results of a cohort of the EVOS study followed over 6 months and observed that the incidence of vertebral fractures was 4 times greater than in those of the hip. The incidence of VF was found, according to these studies, in some 1,250 cases per 100,000 women.
All these data reflect the true situation in Europe, in which vertebral fractures have a prevalence of 12% at 60 years of age and increase progressively with age until they reach 25% at 75 years in women and 17% in men. These data confirm in VF the fact that its highest incidence occurs in a person’s 60s and 70s6 when being active is so important, and thus its social impact and its affect on quality of life is going to be key.
The greatest impact on quality of life of the patient who has suffered a VF is that this fact alone constitutes the greatest risk factor for suffering a new fracture6. From the point of view of economics, VF has been estimated as having a global cost, depending on age, of between 90 and 190 million dollars in the year 2005 (Table 2)7. Clearly the individual costs of each fracture is going to depend on the procedures carried out, admission to hospital, vertebroplasty or kyphoplasty, etc., in addition to the indirect costs occasioned if the person affected is an active worker.
One truly important aspect is the morbidity and worsening of quality of life caused by the VF. The measurement of quality of life in osteoporosis, and essentially in fractures, is usually carried out with specific quality of life questionnaires, such as Health-Related Quality Of Life (HRQOL), QUALEFFCO or ECOS16. The study by Hallberg et al.8 was able to show that a cohort of 600 consecutive women with osteoporotic fractures of between 55 and 75 years of age, worsened their quality of life, measured by means of the HRQOL ,two years after the fracture. The principal and most important clinical effect of VF is the pain it causes, which provokes the immobilisation of the patient and high consumption of analgesics. In addition, the pain goes on to provoke respiratory complications, above all in patients with pulmonary diseases, with the consequent increased impact on their quality of life, and even increasing their risk of mortality. In fact, in order to quantify, in an epidemiological way, the repercussions of the fracture on an individual, the concept of loss of Disability Adjusted Life Years (DALYs) has been established. Using this concept Johnell et al.9 showed that in the year 2000, in which it was estimated that 9 million osteoporotic fractures occurred, 5.8 million DALYs were lost globally, which represents a greater loss than for cancer (except for lung cancer) or for arthritis.
With respect to mortality, in the Fracture Intervention Trial, Cauley et al.10 analysed the mortality data for women of between 55 and 81 years of age, with a follow up of 3.8 years. The relative risk adjusted for age of dying after a clinical vertebral fracture was 8.64 (95% CI: 4.45-16.74). Recently, the results of the Canadian Multicentre Osteoporosis Study (CAMO) have shown that in a cohort of 7,753 patients (2,187 males and 5,566 women) followed over 65 years that the mortality of those patients who had suffered a VF during the second year of follow up is increased 2.7 times at 5 years11.

Femoral fracture

The incidence of FF is an index which represents the national situation with respect to the importance of osteoporosis in that country. In an epidemiological study it was estimated that in 1990 1.31 million new FFs were produced globally, of which 690,382 were in North America, Eastern Europe, Japan and Australia, and in the world there were a total of 4,481,541 people with some disability due to having suffered an FF12.
In Spain, the incidence of femoral fractures has been known for the different regions, having a tendency to increase, probably due to the effect of the aging population (Table 3)13-17. Serra et al.18 carried out a longitudinal study of incidence in each of the regions of Spain, based on the records of the Ministry of Health and Consumption for the years 1996 to 1999. During this period, a total of 130,414 cases were recorded in patients over 65 years of age. They observed that the 89% of patients with hip fracture had an average age of 82 years, with wide variations in incidence between different parts of Spain, but approximating to 270 cases per 100,000 inhabitants in males and 695 per 100,000 in women over 64 years of age.
Recently, in the context of the Bone Ultrasound in Primary Care (Ecografía Ósea en Atención Primaria (ECOSAP)) study the incidence of femoral fractures in women older than 65 years was 360 cases per 100,000 women per year19.
In terms of the economic impact of FF, the annual cost has been estimated at 9,000 million dollars, with some 300,000 hospitalisations for this reason. In Spain, the direct costs alone of the intervention and hospitalisation could amount to 90,000 euros annually. However, what must also be considered, in addition to the costs directly related to the acute phase of the fracture, is the cost related to convalescence, rehabilitation, and indirect costs such as a personal home carer or admission to geriatric centres or residences, which represent 43% of the total cost of treatment of FF7. In terms of the morbimortality of FF, it is well known that the mortality in the acute phase is in the region of 8% within the first month as a consequence of immediate postoperative complications, and a mortality after a year of 30%, which reaches 38% at two years. The previous cognitive state of the patient appears to be a predictive factor of mortality. On the other hand, if there is dementia or senile involution, this is seen to be increased even more after the femoral fracture, which leads to a greater deterioration in the patient’s general state20.
Unfortunately, and despite all the efforts made in recent years, the mortality of FF assessed recently in countries such as Denmark, continues to be very similar at 9% at one month, 15.5% at 3 months, 26.5% at one year and 36.2% at two years21.

Non-vertebral fractures

Until recently NVFs excluding the hip appeared to have little importance, probably due to FF being the key objective in the treatment of OP. However, in recent years, greater importance has been granted to this type of fracture, above all because it represents 67% of all osteoporotic fractures1. In Spain the ECOSAP study has brought this matter to light, and the incidences of each type of fracture in the Spanish population reflect their importance (Table 4)19.
However, the direct and indirect economic costs of this type of fracture is much more difficult to determine, although in some cases, such as the fracture of the forearm, or Colles fracture, some approximations have been made. Thus, Ohsfeldt et al.22, estimated the costs of forearm fractures in the USA in 2003 to be 2,688 US$ per fracture per year. Also here, the indirect economic repercussions due, for example, to time off work or to secondary disability of movement due to poor consolidation, are more difficult to quantify.
In relation to the morbidity and mortality of NVFs, the situation is more complicated since there are no data on this matter at a global level. The repercussions most studied centre on Colles fractures or those of the forearm: those known are the complication of complex regional pain syndrome or the loss of strength of grip in the hand, post-fracture. In spite of this, their true incidence after fracture is not known with exactitude, although what is known is the necessity for early rehabilitation after immobilisation23.

Conclusions

The socioeconomic impact of osteoporosis is truly important, from the prevention of fractures, and their treatment, to their later repercussions, the disease is one which has greater impact on the global health budget. From the data which can be obtained from the pharmaceutical companies for the sales of their products, the epidemiological data, and figures about the different fractures, above all that of the femur, is what makes osteoporosis considered to be a true social-health problem of the 21st century.

BIBLIOGRAPHY
1. Boonen S, Singer AJ. Osteoporosis management: impact of fracture type on cost and quality of life in patients at risk for fracture I. Curr Med Res Opin 2008;24:1781-8.
2. Herrera A, Martínez AA, Ferrandez L, Gil E, Moreno A. Epidemiology of osteoporotic hip fractures in Spain. Int Orthop 2006;30:11-4.
3. Cooper C, Atkinson EJ, O’Fallon WM, Melton LJ 3rd Incidence of clinically diagnosed vertebral fractures: a population-based study in Rochester, Minnesota, 1985-1989. J Bone Miner Res 1992;7:221-7.
4. O’Neill TW, Felsenberg D, Varlow J, Cooper C, Kanis JA, Silman AJ. The prevalence of vertebral deformity in european men and women: the European Vertebral Osteoporosis Study. J Bone Miner Res 1996;11:1010-8.
5. Naves Díaz M, Díaz López JB, Gómez Alonso C, Altadill Arregui A, Rodríguez Rebollar A, Cannata Andia JB. Estudio de incidencia de fracturas osteoporóticas en una cohorte de inividuos mayores de 50 años en Asturias tras 6 años de seguimiento. Med Clin (Barc) 2000;115:650-3.
6. Johnell O, Kanis J. Epidemiology of osteoporotic fractures. Osteoporos Int 2005;16 (Suppl 2): S3-S7.
7. Burge R, Dawson-Hughes B, Solomon DH, Wong JB, King A, Tosteson A. Incidence and economic burden of osteoporosis-related fractures in the United States, 2005-2025. J Bone Miner Res 2007;22:465-75.
8. Hallberg I, Rosenqvist AM, Kartous L, Löfman O, Wahlström O, Toss G. Health-related quality of life after osteoporotic fractures. Osteoporos Int 2004;15:834-41.
9. Johnell O, Kanis JA. An estimate of the worldwide prevalence and disability associated with osteoporotic fractures. Osteoporos Int 2006;17:1726-33.
10. Cauley JA, Thompson DE, Ensrud KC, Scott JC, Black D. Risk of mortality following clinical fractures. Osteoporos Int 2000;11:556-61.
11. Ioannidis G, Papaioannou A, Hopman WM, Akhtar-Danesh N, Anastassiades T, Pickard L, et al. Relation between fractures and mortality: results from the Canadian Multicentre Osteoporosis Study. CMAJ 2009;181:265-71.
12. O. Johnell Æ J. A. Kanis An estimate of the worldwide prevalence, mortality and disability associated with hip fracture Osteoporos Int 2004;15:897-902.
13. Sosa M, Arbelo A, Láinez P, Navarro MC. Datos actualizados sobre la epidemiología de la fractura osteoporótica en España. Rev Esp Enf Metab Óseas 1998;7:174-9.
14. Olmos JM, Martínez J, García J, Matorras P, Moreno JJ, Gonzalez-Macías J. Incidencia de la fractura de cadera en Cantabria. Med Clin (Barc) 1992;99:729-31.
15. Díez A, Puig J, Martínez MT, Díez JL, Aubía J, Vivancos J. Epidemiology of fractures of the proximal femur associated with osteoporosis in Barcelona, Spain. Calcifie Tissue Int 1989;44:382-6.
16. Arboleya LR, Castro MA, Bartolome E, Gervas L, Vega R. Epidemiología de la fractura osteoporótica de cadera en la provincia de Palencia. Rev Clin Esp 1997;197:611-7.
17. Nogues X, Díez A, Puig J, Martínez MT, Cucurull J, Supervía A, et al. Cambios en los índices de hospitalización por fractura femoral osteoporótica en Barcelona durante el período 1984-1989. Rev Esp Enf Metab Óseas 1997:6:41-4.
18. Serra JA, Garrida G, Vidan M, Maramon E, Branas F, Ortiz J. Epidemiologia de la fractura de cadera en la ancianidad España. An Med Interna 2002;19:389-95.
19. Marín F, González-Macías J, Moya R, Onrubia C, Cancelo C, Alvarez S, et al. ECOSAP. Fractura no vertebral por fragilidad en una cohorte de 5.201 mujeres de 65 años o más durante 3 años de seguimiento. Med Clin (Barc) 2006;127:401-4.
20. Knobel H, Díez A, Arnau D, Alier A, Ibáñez J, Campodarve I, et al. Secuelas de la Fractura de fémur en Barcelona. Med Clin (Barc) 1992;98:441-4
21. Giversen IM. Time trends of mortality after first hip fractures. Osteoporos Int 2007 Jun;18(6):721-32.
22. Ohsfeldt RL, Borisov NN, Sheer RL. Fragility fracture-related direct medical costs in the first year following a nonvertebral fracture in a managed care setting. Osteoporos Int 2006;17:252-8.
23. Watt CF, Taylor NF, Baskus K. Do Colles’ fracture patients benefit from routine referral to physiotherapy following cast removal? Arch Orthop Trauma Surg 2000;120:413-5.