p u b l i c h e a l t h 1 2 8 ( 2 0 1 4 ) 1 1 2 5 e1 1 2 7
Available online at www.sciencedirect.com
Public Health journal homepage: www.elsevier.com/puhe
Short Communication
Osteoporosis hospital admissions varied across sub-regions but not seasons in England: Hospital Episode Statistics, 2008e2011 D. Chown a,b, I. Shiue b,c,* a
Budehaven Community School, UK European Centre for Environment and Human Health, University of Exeter, UK c School of the Built Environment, Heriot-Watt University, UK b
article info Article history: Received 4 February 2014 Received in revised form 13 August 2014 Accepted 8 September 2014 Available online 24 November 2014
It is known that osteoporosis is the thinning of bone tissue and loss of bone density over time, leading to an increased risk of bone fracture.1 It is the most common metabolic bone disorder worldwide, and is an increasingly problem, affecting 200 million individuals worldwide.1,2 According to Freedman et al.,3 it is increasing in prevalence and remains largely under-diagnosed and under-treated, attributable in part to the fact that it is a clinically silent disease until it manifests in the form of a fracture. In 1989e1990 to 1997e1998 in England, researchers claimed a concern on the lack of any decrease in hospital admissions and mortality rates for fractures of the hip and femur (International Classification of Diseases version 10: S72.0eS72.9).4 In 1998e2009, researchers still did not observe any decrease (S72.0eS72.2) which could remain a burden for England and be continuously worrying.5 On the other hand, research on geographic and seasonal variations in osteoporosis admissions is scarce. Therefore, this study aimed to examine the geographic and seasonal variations in osteoporosis admissions in England in recent years in order to help provide policy implications for effective medical resource
reallocation. Moreover, it has been hypothesized that more admissions would be recorded in the northern sub-regions than in the southern sub-regions and more in winter time than in summer time owing to less sun exposure. Hospital Episode Statistics (HES) have been extracted between 1 July, 2008 and 30 June, 2011 from Lightfoot Solutions using sfn system (http://www.lightfootsolutions.com/) which gave real-time HES data.6 The HES database contains information about all patients admitted to National Health Service hospitals in England.7 HES online system with complete information is available from 1998 and the dataset contains many variables including age, gender, primary and secondary diagnoses and in-hospital death.8 The basic unit of the data set is the consultant episode, covering the continuous period of time during which a patient was under the care of one consultant. The main reason for admission (‘primary diagnosis’) is coded using the International Classification of Diseases version 10 (ICD-10) codes.9 In the current study, M80M82 in ICD-10 was used to capture osteoporosis admissions. They are defined as follows: M80 e Osteoporosis with pathological fracture; M81 - Osteoporosis without pathological fracture; M82 e Osteoporosis in diseases classified elsewhere. Specifically, a pathological fracture is defined as a break in the bone caused by disease that has led to the weakness of the bone; in this case, osteoporosis. Hospital admissions by geographic and seasonal variations at the regional/ecological level were examined separately. Population size as denominator across regions in 2011 National Census was obtained from the UK Office of National Statistics (http://www.statistics.gov.uk) for admission rates
* Corresponding author. School of the Built Environment, Heriot-Watt University, Riccarton, EH14 4AS Edinburgh, Scotland, UK. Tel.: þ44 131 4514655; fax: þ44 131 4513161. E-mail addresses: [email protected], [email protected] (I. Shiue). http://dx.doi.org/10.1016/j.puhe.2014.09.006 0033-3506/© 2014 The Royal Society for Public Health. Published by Elsevier Ltd. All rights reserved.
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p u b l i c h e a l t h 1 2 8 ( 2 0 1 4 ) 1 1 2 5 e1 1 2 7
calculation purpose (admissions were divided by population size). The following English administrative regions were used according to Strategic Health Authorities (SHA) and organized them in descending order of latitude: North East, North West, Yorkshire and The Humber, East Midlands, West Midlands, East of England, London, South East and the South West. As there was no South East SHA, the South East Coast SHA and the South Central SHA were combined into South East region. Microsoft Office Excel was used to store the data gathered from the HES website and the sfn system, to calculate admission rates, and to create tables and graphs. Since this is only a secondary data analysis by extracting data at the population level (no patient personal information disclosed) from HES (Lightfoot Solutions using sfn system) and from Office of National Statistics, no further ethics approval was required. Table 1a, showed that the lowest admission rates for osteoporosis were in the middle of England (25.7 per 100,000 in East Midlands and 38.9 per 100,000 in West Midlands). Northern regions seemed to have higher admission rates than the southern regions, although there was a peak observed in South East (72.8 per 100,000) as well. However, emergency admission rates varied greatly across all regions. This could have two implications: on one hand, the rates of admissions and emergency events could seem to be different due to different size of effect from risk contributors. On the other hand, there might be underreporting for cases in certain regions. A systematic and rigorous monitoring on the current medical system would seem to be necessary. Specific yearly trends from 2008 to 2011 across sub-regions were provided in
the Supplementary Fig. 1 while a further examination by age groups could be found in Table 1b. Also it was observed that there were no variation across months and seasons (P > 0.05; data not shown). In Supplementary Table 1, admission rates and emergency rates of osteoporosis were additionally listed by subtypes from 1998 to 2011 which could provide an overview of the trends over years. Apparently, admission rates have increased over time while emergency rates have decreased, suggesting fewer emergency events in the recent years than in the past. On the other hand, the proportion of male patients seemed to have slightly increased in osteoporosis with pathological fracture but decreased in osteoporosis without pathological fracture. The mean age of admitted patients has not changed. In this study recent evidence on geographical variations in osteoporosis admissions has been provided, which showed higher admissions rates in the northern regions of England than the southern regions (except for South East region) and the lowest in the middle of England. However, admissions between seasons were negligible, with no distinct seasonal pattern in osteoporosis admissions found. Moreover, from 1998 to 2011, admission rates have increased over time while emergency rates have decreased. The proportion of male patients seemed to have slightly increased in osteoporosis with pathological fracture but decreased in osteoporosis without pathological fracture which is consistent with an observation from a previous study between 1998 and 2009. From the current dataset with limited study variables, it is not possible to confirm which aetiological factor(s) could have driven the
Table 1 e Counts and rates for osteoporosis admissions (ICD-10: M80-M82) across sub-regions in England in 2010e2011. a) Overall Region
Admissions count
Admissions ratea
Emergency admissions count
Emergency admissions rateb
1544 3952 4058 1163 2181 2498 3787 2684 2500
59.45550464 56.03925016 76.80224085 25.65516633 38.9339141 42.72276381 46.33039308 72.78686246 47.26880826
225 497 363 289 282 304 332 460 356
16.80% 13.29% 9.93% 25.03% 14.55% 15.32% 8.90% 7.93% 21.88%
North east North west Yorkshire & the Humber East Midlands West Midlands East of England London South east South west
b) by age groups Region
North east North west Yorkshire & the Humber East Midlands West Midlands East of England London South east South west a b
15e64 yrs 15e64 yrs 15e64 yrs 65þ yrs 65þ yrs 65þ yrs 0e14 yrs 0e14 yrs 0e14 yrs admission population admissions admission population admissions admission population admissions count ratea count ratea count ratea 0 161 49
427789 1214322 910237
0 13.25842734 5.383213383
2314 6430 3286
1729880 4561959 3523351
133.766504 140.9482198 93.26348695
9598 24820 14047
448956 1159455 867664
2137.848698 2140.660914 1618.944661
38 63 46 108 46 14
764136 988408 1028950 1450041 1504863 862342
4.972936755 6.373886088 4.470576802 7.448065262 3.056756662 1.62348581
1993 3017 3195 5625 3776 2957
2948807 3529383 3784597 5472864 5549262 3376535
67.58665454 85.48236335 84.4211418 102.7798242 68.04508419 87.57498441
8574 12375 12761 15427 17581 13232
768488 937388 1018298 902272 1468949 1034849
1115.697317 1320.157715 1253.169504 1709.794829 1196.842096 1278.640652
Number of individuals per 100,000 members of the population that were admitted for osteoporosis. Percentage of all admissions that were emergency admissions.
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changes. Future research looking into this would be suggested. Strengths of this study lie in its large country-wide, population-based, representative sample. Also, for the first time, geographic variations of osteoporosis admissions by subregions in England were examined. However, a few limitations cannot be ignored. The accuracy of HES may depend on clinical diagnoses recorded in patients' medical records, but recent research has shown that the quality of coding has been largely improved.10 HES only provides information relating to NHS hospital admissions, meaning that data for the incidence of osteoporosis among individuals that utilize private health care was unavailable. In addition, the availability of ethnicity data was not sufficiently comprehensive to allow further exploration of ethnicity difference for hospital admissions in the current analysis. Furthermore, because the study was at an ecological level to monitor the burden across space and time, the authors were unable to take into account aetiological factors including biological attributes, socio-economic status and access to health care within each sub-region that may have impacted upon their results and conclusions had been able to take them into account. Osteoporosis hospital admissions varied across subregions but not seasons in England in 2008e2011. On one hand, understanding the variations of osteoporosis hospital admissions across sub-regions in England could assist with re-allocation of social nad medical resources (i.e. beds, treatment availability, doctor's time, nursing time, rehabilitation facilities …) including ambulance use to be more effectively and efficiently. This would need a continuous monitoring as well. On the other hand, more research is needed to look into the mechanism of these inequalities while comparing between the admission rates and incidence rates. Also it has been discovered that there was a gap of 6e9 years between the mean ages for M80 and M81 admissions. Implications from this are that if it is possible to diagnose osteoporosis many years before a pathological fracture, on average, will occur, and if the issues of under-diagnosis and under-treatment could be resolved, then steps could be taken to attempt to prevent the occurrence of a pathological fracture and therefore lower the number of osteoporotic pathological fractures over time, reducing the financial burden on the NHS to provide care and rehabilitation to fracture victims.
Author statements Author contributions IS conducted the study and obtained the data; DC analysed the data; IS and DC together interpreted results and drafted the manuscript.
Funding DC was supported by Nuffield Foundation Science Bursary. IS was supported by European Regional Development Fund and
the European 2007e2013.
Social
Fund
Convergence
Programme
Ethical approval Since this is only a secondary data analysis by extracting data at the population level (no patient personal information disclosed) from HES (Lightfoot Solutions using sfn system) and from Office of National Statistics, no further ethics approval is required.
Competing interests None.
List of abbreviations HES ICD SHA
Hospital Episode Statistics International Classification of Diseases Strategic Health Authorities
Appendix A. Supplementary data Supplementary data related to this article can be found at http://dx.doi.org/10.1016/j.puhe.2014.09.006.
references
1. Lin JT, Lane JM. Osteoporosis e a review. Clin Orthop Relat Res 2004;425:126e34. 2. Parsons LC. Osteoporosis: incidence, prevention, and treatment of the silent killer. Nurs Clin North Am 2005;40:119e33. 3. Freedman KB, Kaplan FS, Bilker WB, Strom BL, Lowe RA. Treatment of osteoporosis: are physicians missing an opportunity? J Bone Jt Surg 2000;82A:1063e70. 4. Balasegaram S, Majeed A, Fitz-Clarence H. Trends in hospital admissions for fractures of the hip and femur in England, 1989e1990 to 1997e1998. J Public Health Med 2001;23:11e7. 5. Wu TY, Jen MH, Bottle A, Liaw CK, Aylin P, Majeed A. Admission rates and in-hospital mortality for hip fractures in England 1998 to 2009: time trends study. J Public Health (Oxf) 2011;33:284e91. 6. Shiue I. Patterns of subarachnoid hemorrhage admissions in England, 2008e2011. Eur Neurol 2013;69:242e5. 7. Hospital Episode Statistics. Available at: http://www. hesonline.nhs.uk (accessed 12 August 2012). 8. Campbell S, Campbell M, Grimshaw J, Walker A. A systematic review of discharge coding accuracy. J Public Health Med 2001;23:205e11. 9. World Health Organization. International classification of diseases (ICD) version 10 (accessed 12 August 2012), http://apps. who.int/classifications/apps/icd/icd10online/; 2009. 10. Bryden C, Bird W, Titley HA, Halpin DMG, Levy ML. Stratification of COPD patients by previous admission for targeting of preventative care. Respir Med 2009;103:558e65.
Available online at www.sciencedirect.com
Public Health journal homepage: www.elsevier.com/puhe
Short Communication
Osteoporosis hospital admissions varied across sub-regions but not seasons in England: Hospital Episode Statistics, 2008e2011 D. Chown a,b, I. Shiue b,c,* a
Budehaven Community School, UK European Centre for Environment and Human Health, University of Exeter, UK c School of the Built Environment, Heriot-Watt University, UK b
article info Article history: Received 4 February 2014 Received in revised form 13 August 2014 Accepted 8 September 2014 Available online 24 November 2014
It is known that osteoporosis is the thinning of bone tissue and loss of bone density over time, leading to an increased risk of bone fracture.1 It is the most common metabolic bone disorder worldwide, and is an increasingly problem, affecting 200 million individuals worldwide.1,2 According to Freedman et al.,3 it is increasing in prevalence and remains largely under-diagnosed and under-treated, attributable in part to the fact that it is a clinically silent disease until it manifests in the form of a fracture. In 1989e1990 to 1997e1998 in England, researchers claimed a concern on the lack of any decrease in hospital admissions and mortality rates for fractures of the hip and femur (International Classification of Diseases version 10: S72.0eS72.9).4 In 1998e2009, researchers still did not observe any decrease (S72.0eS72.2) which could remain a burden for England and be continuously worrying.5 On the other hand, research on geographic and seasonal variations in osteoporosis admissions is scarce. Therefore, this study aimed to examine the geographic and seasonal variations in osteoporosis admissions in England in recent years in order to help provide policy implications for effective medical resource
reallocation. Moreover, it has been hypothesized that more admissions would be recorded in the northern sub-regions than in the southern sub-regions and more in winter time than in summer time owing to less sun exposure. Hospital Episode Statistics (HES) have been extracted between 1 July, 2008 and 30 June, 2011 from Lightfoot Solutions using sfn system (http://www.lightfootsolutions.com/) which gave real-time HES data.6 The HES database contains information about all patients admitted to National Health Service hospitals in England.7 HES online system with complete information is available from 1998 and the dataset contains many variables including age, gender, primary and secondary diagnoses and in-hospital death.8 The basic unit of the data set is the consultant episode, covering the continuous period of time during which a patient was under the care of one consultant. The main reason for admission (‘primary diagnosis’) is coded using the International Classification of Diseases version 10 (ICD-10) codes.9 In the current study, M80M82 in ICD-10 was used to capture osteoporosis admissions. They are defined as follows: M80 e Osteoporosis with pathological fracture; M81 - Osteoporosis without pathological fracture; M82 e Osteoporosis in diseases classified elsewhere. Specifically, a pathological fracture is defined as a break in the bone caused by disease that has led to the weakness of the bone; in this case, osteoporosis. Hospital admissions by geographic and seasonal variations at the regional/ecological level were examined separately. Population size as denominator across regions in 2011 National Census was obtained from the UK Office of National Statistics (http://www.statistics.gov.uk) for admission rates
* Corresponding author. School of the Built Environment, Heriot-Watt University, Riccarton, EH14 4AS Edinburgh, Scotland, UK. Tel.: þ44 131 4514655; fax: þ44 131 4513161. E-mail addresses: [email protected], [email protected] (I. Shiue). http://dx.doi.org/10.1016/j.puhe.2014.09.006 0033-3506/© 2014 The Royal Society for Public Health. Published by Elsevier Ltd. All rights reserved.
1126
p u b l i c h e a l t h 1 2 8 ( 2 0 1 4 ) 1 1 2 5 e1 1 2 7
calculation purpose (admissions were divided by population size). The following English administrative regions were used according to Strategic Health Authorities (SHA) and organized them in descending order of latitude: North East, North West, Yorkshire and The Humber, East Midlands, West Midlands, East of England, London, South East and the South West. As there was no South East SHA, the South East Coast SHA and the South Central SHA were combined into South East region. Microsoft Office Excel was used to store the data gathered from the HES website and the sfn system, to calculate admission rates, and to create tables and graphs. Since this is only a secondary data analysis by extracting data at the population level (no patient personal information disclosed) from HES (Lightfoot Solutions using sfn system) and from Office of National Statistics, no further ethics approval was required. Table 1a, showed that the lowest admission rates for osteoporosis were in the middle of England (25.7 per 100,000 in East Midlands and 38.9 per 100,000 in West Midlands). Northern regions seemed to have higher admission rates than the southern regions, although there was a peak observed in South East (72.8 per 100,000) as well. However, emergency admission rates varied greatly across all regions. This could have two implications: on one hand, the rates of admissions and emergency events could seem to be different due to different size of effect from risk contributors. On the other hand, there might be underreporting for cases in certain regions. A systematic and rigorous monitoring on the current medical system would seem to be necessary. Specific yearly trends from 2008 to 2011 across sub-regions were provided in
the Supplementary Fig. 1 while a further examination by age groups could be found in Table 1b. Also it was observed that there were no variation across months and seasons (P > 0.05; data not shown). In Supplementary Table 1, admission rates and emergency rates of osteoporosis were additionally listed by subtypes from 1998 to 2011 which could provide an overview of the trends over years. Apparently, admission rates have increased over time while emergency rates have decreased, suggesting fewer emergency events in the recent years than in the past. On the other hand, the proportion of male patients seemed to have slightly increased in osteoporosis with pathological fracture but decreased in osteoporosis without pathological fracture. The mean age of admitted patients has not changed. In this study recent evidence on geographical variations in osteoporosis admissions has been provided, which showed higher admissions rates in the northern regions of England than the southern regions (except for South East region) and the lowest in the middle of England. However, admissions between seasons were negligible, with no distinct seasonal pattern in osteoporosis admissions found. Moreover, from 1998 to 2011, admission rates have increased over time while emergency rates have decreased. The proportion of male patients seemed to have slightly increased in osteoporosis with pathological fracture but decreased in osteoporosis without pathological fracture which is consistent with an observation from a previous study between 1998 and 2009. From the current dataset with limited study variables, it is not possible to confirm which aetiological factor(s) could have driven the
Table 1 e Counts and rates for osteoporosis admissions (ICD-10: M80-M82) across sub-regions in England in 2010e2011. a) Overall Region
Admissions count
Admissions ratea
Emergency admissions count
Emergency admissions rateb
1544 3952 4058 1163 2181 2498 3787 2684 2500
59.45550464 56.03925016 76.80224085 25.65516633 38.9339141 42.72276381 46.33039308 72.78686246 47.26880826
225 497 363 289 282 304 332 460 356
16.80% 13.29% 9.93% 25.03% 14.55% 15.32% 8.90% 7.93% 21.88%
North east North west Yorkshire & the Humber East Midlands West Midlands East of England London South east South west
b) by age groups Region
North east North west Yorkshire & the Humber East Midlands West Midlands East of England London South east South west a b
15e64 yrs 15e64 yrs 15e64 yrs 65þ yrs 65þ yrs 65þ yrs 0e14 yrs 0e14 yrs 0e14 yrs admission population admissions admission population admissions admission population admissions count ratea count ratea count ratea 0 161 49
427789 1214322 910237
0 13.25842734 5.383213383
2314 6430 3286
1729880 4561959 3523351
133.766504 140.9482198 93.26348695
9598 24820 14047
448956 1159455 867664
2137.848698 2140.660914 1618.944661
38 63 46 108 46 14
764136 988408 1028950 1450041 1504863 862342
4.972936755 6.373886088 4.470576802 7.448065262 3.056756662 1.62348581
1993 3017 3195 5625 3776 2957
2948807 3529383 3784597 5472864 5549262 3376535
67.58665454 85.48236335 84.4211418 102.7798242 68.04508419 87.57498441
8574 12375 12761 15427 17581 13232
768488 937388 1018298 902272 1468949 1034849
1115.697317 1320.157715 1253.169504 1709.794829 1196.842096 1278.640652
Number of individuals per 100,000 members of the population that were admitted for osteoporosis. Percentage of all admissions that were emergency admissions.
1127
p u b l i c h e a l t h 1 2 8 ( 2 0 1 4 ) 1 1 2 5 e1 1 2 7
changes. Future research looking into this would be suggested. Strengths of this study lie in its large country-wide, population-based, representative sample. Also, for the first time, geographic variations of osteoporosis admissions by subregions in England were examined. However, a few limitations cannot be ignored. The accuracy of HES may depend on clinical diagnoses recorded in patients' medical records, but recent research has shown that the quality of coding has been largely improved.10 HES only provides information relating to NHS hospital admissions, meaning that data for the incidence of osteoporosis among individuals that utilize private health care was unavailable. In addition, the availability of ethnicity data was not sufficiently comprehensive to allow further exploration of ethnicity difference for hospital admissions in the current analysis. Furthermore, because the study was at an ecological level to monitor the burden across space and time, the authors were unable to take into account aetiological factors including biological attributes, socio-economic status and access to health care within each sub-region that may have impacted upon their results and conclusions had been able to take them into account. Osteoporosis hospital admissions varied across subregions but not seasons in England in 2008e2011. On one hand, understanding the variations of osteoporosis hospital admissions across sub-regions in England could assist with re-allocation of social nad medical resources (i.e. beds, treatment availability, doctor's time, nursing time, rehabilitation facilities …) including ambulance use to be more effectively and efficiently. This would need a continuous monitoring as well. On the other hand, more research is needed to look into the mechanism of these inequalities while comparing between the admission rates and incidence rates. Also it has been discovered that there was a gap of 6e9 years between the mean ages for M80 and M81 admissions. Implications from this are that if it is possible to diagnose osteoporosis many years before a pathological fracture, on average, will occur, and if the issues of under-diagnosis and under-treatment could be resolved, then steps could be taken to attempt to prevent the occurrence of a pathological fracture and therefore lower the number of osteoporotic pathological fractures over time, reducing the financial burden on the NHS to provide care and rehabilitation to fracture victims.
Author statements Author contributions IS conducted the study and obtained the data; DC analysed the data; IS and DC together interpreted results and drafted the manuscript.
Funding DC was supported by Nuffield Foundation Science Bursary. IS was supported by European Regional Development Fund and
the European 2007e2013.
Social
Fund
Convergence
Programme
Ethical approval Since this is only a secondary data analysis by extracting data at the population level (no patient personal information disclosed) from HES (Lightfoot Solutions using sfn system) and from Office of National Statistics, no further ethics approval is required.
Competing interests None.
List of abbreviations HES ICD SHA
Hospital Episode Statistics International Classification of Diseases Strategic Health Authorities
Appendix A. Supplementary data Supplementary data related to this article can be found at http://dx.doi.org/10.1016/j.puhe.2014.09.006.
references
1. Lin JT, Lane JM. Osteoporosis e a review. Clin Orthop Relat Res 2004;425:126e34. 2. Parsons LC. Osteoporosis: incidence, prevention, and treatment of the silent killer. Nurs Clin North Am 2005;40:119e33. 3. Freedman KB, Kaplan FS, Bilker WB, Strom BL, Lowe RA. Treatment of osteoporosis: are physicians missing an opportunity? J Bone Jt Surg 2000;82A:1063e70. 4. Balasegaram S, Majeed A, Fitz-Clarence H. Trends in hospital admissions for fractures of the hip and femur in England, 1989e1990 to 1997e1998. J Public Health Med 2001;23:11e7. 5. Wu TY, Jen MH, Bottle A, Liaw CK, Aylin P, Majeed A. Admission rates and in-hospital mortality for hip fractures in England 1998 to 2009: time trends study. J Public Health (Oxf) 2011;33:284e91. 6. Shiue I. Patterns of subarachnoid hemorrhage admissions in England, 2008e2011. Eur Neurol 2013;69:242e5. 7. Hospital Episode Statistics. Available at: http://www. hesonline.nhs.uk (accessed 12 August 2012). 8. Campbell S, Campbell M, Grimshaw J, Walker A. A systematic review of discharge coding accuracy. J Public Health Med 2001;23:205e11. 9. World Health Organization. International classification of diseases (ICD) version 10 (accessed 12 August 2012), http://apps. who.int/classifications/apps/icd/icd10online/; 2009. 10. Bryden C, Bird W, Titley HA, Halpin DMG, Levy ML. Stratification of COPD patients by previous admission for targeting of preventative care. Respir Med 2009;103:558e65.
