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Ambulatory health care utilization of the older people under the National Health Insurance in Taiwan
Journal of Clinical Gerontology & Geriatrics 2 (2011) 53e57
Contents lists available at ScienceDirect
Journal of Clinical Gerontology & Geriatrics journal homepage: www.e-jcgg.com
Original article
Ambulatory health care utilization of the older people under the National Health Insurance in Taiwan Yi-Tsong Lin, MD a, b, c, Shinn-Jang Hwang, MD b, c, *, Liang-Kung Chen, MD b, c, Tzeng-Ji Chen, MD, PhD b, c, I-Hsuan Hwang, BA d a
Banchiao Veterans Home, Taipei County, Taiwan Department of Family Medicine, Center for Geriatrics and Gerontology, Taipei Veterans General Hospital, Taipei, Taiwan Department of Family Medicine, National Yang Ming University School of Medicine, Taipei, Taiwan d Department of Business Administration, Shin-Chien University, College of Management, Taipei, Taiwan b c
a r t i c l e i n f o
a b s t r a c t
Article history: Received 20 August 2010 Received in revised form 28 December 2010 Accepted 30 January 2011
Background/Purpose: To analyze and describe the patterns of ambulatory care utilization by the older people within the Taiwanese National Health Insurance (NHI) program. Methods: The nationwide computerized claims database of elderly ambulatory care visits under the NHI in 2004 was accessed. We obtained the complete outpatients service claim data sets of Western medicine for beneficiaries S 65 years old. We then analyzed the pattern and frequency of visits by patient age, sex, and primary diagnosis. Results: In 2004, 96.6% of all elderly NHI beneficiaries had ever used ambulatory care service and there were totally 57,101,420 ambulatory care visits records from these elderly beneficiaries. The average ambulatory visit number of each beneficiary is 26.8 22.7 (mean standard deviation) times per year, which was much higher than United States and other Organization for Economic Co-operation and Development countries. Nearly one-half of the elderly had more than 24 times visits annually. Female beneficiaries had higher average annual ambulatory visit number but lower mean medical expense per visit than male beneficiaries. The middle old age group (75e84 years old) had highest average visits numbers (29.2 23.3) and highest average medical expense per visit: 37.1 US dollar. The three most frequent principal diagnoses of elderly ambulatory visits were diseases of the circulatory system (17.3%), diseases of the respiratory system (15.9%), and diseases of the musculoskeletal system and connective tissue (12.8%), respectively. While compared with United States data, the proportion of acute upper airway infection was much higher among old age ambulatory visits in Taiwan. Conclusion: The mean frequency of ambulatory visits of older people in Taiwan was high, especially in the middle-old age group. Health education and preventive services should focus on circulatory, respiratory, and musculoskeletal diseases, which accounted for nearly one-half of the primary diagnoses of old age ambulatory visits. Copyright Ó 2011, Asia Pacific League of Clinical Gerontology & Geriatrics. Published by Elsevier Taiwan LLC. All rights reserved.
Keywords: Ambulatory care visits Elderly Health care utilization Medical expense National Health Insurance
1. Introduction The world population is aging now. With the decrease in birth rate and prolonged life expectancy, almost every country has an increasing elderly population.1e3 However, living longer means there are more chances to suffer from acute or chronic illness.
* Corresponding author. Department of Family Medicine, Center for Geriatrics and Gerontology, Taipei Veterans General Hospital, No. 201, Shih-Pai Road, Section 2, Taipei 11217, Taiwan. E-mail address: [email protected] (S.-J. Hwang).
Previous studies proved that old age population usually accounts for the biggest proportion of a country’s health care cost while comparing with young age groups.4,5 But there are very few published studies evaluating the health care resources utilization between different old age groups, which is also very important. Furthermore, ambulatory health care accounts for most health care expenditure in most countries.6 In United State, people aged 65 and older account for 30%e40% of primary care physician visits.7e9 So if we want to look into the issue of increasing health cost in one country and try to find out some possible solutions, the ambulatory health care utilization by the elderly population must be studied and analyzed.
2210-8335/$ e see front matter Copyright Ó 2011, Asia Pacific League of Clinical Gerontology & Geriatrics. Published by Elsevier Taiwan LLC. All rights reserved. doi:10.1016/j.jcgg.2011.03.002
54
Y.-T. Lin et al. / Journal of Clinical Gerontology & Geriatrics 2 (2011) 53e57
As in many developed countries, Taiwan’s society has a dramatic shift under way toward a graying population. Till the end of 2007, 10.2% of total Taiwan population were aged 65 years and older, and the percentage is still increasing rapidly.10 The Taiwanese National Health Insurance (NHI) program, a social health insurance, provides universal coverage to most inhabitants. Beneficiaries can obtain medical services at the clinic or hospital by their choice without a referral. The purpose of our study was to describe and analyze the patterns of ambulatory care visit of elderly people in Taiwan within the NHI in 2004. We focused on the frequency and diagnoses of ambulatory visits and tried to analyze the difference between different old age groups. We hoped the findings might provide some evidence for health policymaking.
3. Results 3.1. General information of the study In 2004, all beneficiaries had a total of 57,101,420 ambulatory care visits. There were totally 2,128,388 beneficiaries who had ever used NHI ambulatory care service, equivalent to 96.6% of all elderly beneficiaries. Among them, 1,056,902 (49.7%) were male and 1,059,936 (49.8%) were female. If divided by age groups, 1,254,413 (58.9%) subjects belonged to young-old age group, 723,774 (34.0%) subjects, and 150,201 (7.1%) subjects belonged to middle-old age group and old-old age group, respectively. 3.2. Visits frequency and medical expense by sex and age group
2. Methods 2.1. Data source and study design The data source of this study mainly come from the National Health Insurance Research Database (NHIRD) project of the National Health Research Institute. The NHI program was initiated in Taiwan since 1995. It is a universal insurance program and covers nearly all inhabitants (at the end of 2004, it had 97.6% coverage rate) in Taiwan.11,12 In 1999, the Bureau of National Health Insurance began to release all claims data in electronic form to the public under the project of NHIRD. The details about the NHI program and the structure of the claims data sets are described on the NHIRD Web site13 and in our previous publications.14e16 In this study, we obtained the complete outpatients service claims data sets of beneficiaries aged S65 years old (CD2004.DAT) from NHIRD. These data sets contained the ambulatory care clinics and emergency department visiting files, including dates, medical care facilities and physicians’ specialties, patients’ genders, dates of birth, the three major diagnoses coded in the International Classification of Disease, Ninth Revision, Clinical Modification (ICD-9-CM) format and the medical expense (contains the drug fee; medical procedures, including laboratory tests and roentgenographic examinations; treatment and medical supply; diagnosis fee; and pharmacy dispensing service fee, physician charge is not included.) of each visit from all medical care institutions under contract with the Bureau of National Health Insurance in Taiwan. To protect privacy, data identifying patients had been scrambled cryptographically. Among all old age ambulatory visit records in 2004, we only took the Western medicine outpatients service data for analyses, emergency visits of older population were not analyzed. We at first divided all beneficiaries into three different age groups: the youngold age group (65e74 years old), middle-old age group (75e84 years old) and old-old age group (85 years old and older). Then, we calculated the mean annual outpatients service visit numbers and mean medical expense per visit among different age groups. To investigate the relationship between age and visits frequency, we calculated each beneficiary’s annual visits numbers and displayed both in numbers of visits and in numbers of patients by different age groups. We also calculated the frequency distribution of principal diagnoses at all visits by ICD-9-CM chapter. 2.2. Statistical methods The database software of Microsoft SQL Server 2008 (Microsoft Corp., Redmond, WA, USA) was used for data linkage and processing. Descriptive data are presented in the text and tables, including frequencies, numbers, percentages, and means. The regular statistics were displayed as mean standard deviation (mean SD).
In 2004, each elderly beneficiary had an average of 26.8 ambulatory visits annually. Female beneficiaries had higher mean frequency of ambulatory visits but lower mean medical expense per visit than male [26.2 21.2 times vs. 24.9 22.1 times; 35.9 United States Dollar (USD) vs. 37.3 USD]. When analyzing among different old age groups, the middle old age group had the highest mean frequency of ambulatory visit (29.2 23.3 times), followed by young-old age group (25.7 21.3 times), and old-old age group (25.2 22.8 times) (Table 1). The mean medical expense per ambulatory visit was 36.8 USD (range: 0e16,368 USD). When comparing among three age groups, the old-old age group had the lowest mean medical expense per visit (34.0 USD, range: 0e8331 USD), followed by young- and middle-old age group. The most frequent number of annual ambulatory visits was 13e24 times per year (1e2 times per month), followed by 25e36 times per year (2e3 times per month), 3e12 times, 49e96 times, and 37e48 times per year. Near one-half (45.9%) of all beneficiaries had ever visited ambulatory clinics more than 24 times annually (Table 2). More than one-half of middle age elderly (50.7%) had a mean ambulatory visits more than 24 times per year, higher than 43.8% in young-old elderly and 41.6% in the old-old elderly. 3.3. Distribution of ambulatory care visits by principal diagnosis Diseases of the circulatory system (n ¼ 9,864,098; 17.3%), diseases of the respiratory system (n ¼ 9,103,118; 15.9%), and diseases of the musculoskeletal system and connective tissue (n ¼ 7,325,556; 12.8%) were the top three primary diagnosis of elderly ambulatory visits (Table 3). Almost one-half of all visits had either one of these three diseases as the principal diagnosis. If we analyzed the primary diagnosis of ambulatory care visits among
Table 1 The mean annual visit numbers and mean medical expense per visit by gender and age groups among older people in Taiwan under the National Health Insurance in 2004 Mean annual visit numbers per persona
Mean medical expense per visitb
Gender Male Female
24.9 22.1 26.2 21.2
37.3 35.9
Age group 65e74 yr old 75e4 yr old S85 yr old All age
25.7 21.3 29.2 23.3 25.2 22.8 26.8 22.7
36.9 37.1 34.0 36.8
Gender and age group
a
Data were expressed with mean standard deviation. Medical expense ¼ Drug fee þ medical procedures, including laboratory tests and roentgenographic examinations þ treatment and medical supply þ diagnosis fee þ pharmacy dispensing service fee in US Dollars. b
Y.-T. Lin et al. / Journal of Clinical Gerontology & Geriatrics 2 (2011) 53e57
55
Table 2 Distribution of the beneficiary’s ambulatory visit frequency by different age groups Number of visit in 2004 per person
65e74 yr old, n (%) (n ¼ 12,54,413)
75e84 yr old, n (%) (n ¼ 723,774)
S85 yr old, n (%) (n ¼ 150,201)
All age, n (%) (n ¼ 21,28,388)
<3 3e12 13e24 25e36 37e48 49e96 >96
70,778 255,542 378,985 253,421 137,890 141,773 16,064
34,244 117,337 204,938 154,329 92,134 106,722 14,070
12,410 32,282 43,031 27,309 15,069 17,676 2424
117,432 405,161 626,954 435,059 245,093 266,171 32,558
(5.6) (20.4) (30.2) (20.2) (11.0) (11.3) (1.3)
three old age groups, the three most frequent diagnoses of youngold age group were acute upper airway infection (ICD-9-CM code: 465, accounted for 7.2% of total young-old population), essential hypertension (ICD-9-CM code: 401, 6.6% of total young-old population), and diabetes mellitus (ICD-9-CM code: 250, 5.8% of total young-old population), whereas in the middle-old age group, they were essential hypertension (6.7%), acute upper airway infection (5.8%), and diabetes mellitus (4.8%), and in old-old age group, they were essential hypertension(6.4%), acute upper airway infection (5.5%), and hypertensive heart disease (ICD-9-CM code: 401, 3.4%), respectively (Table 4). 4. Discussion Taiwan, like many other countries, is facing an increasing elderly population, and the increase in old age population has become the biggest burden of a country’s health care system. In United States, the average annual health care expenditure of the elderly people was increased from 2200 USD per person in 1991 to 4300 USD per person in 2006.17 In Taiwan, the number of elderly population has accounted for 10.4% of total population, but accounted for 39.3% of total medical expenditure.18 Among the total medical expenditure, ambulatory care service accounts for the major part (9.04 billion USD for ambulatory care service, equivalent to 65.7% to total health care expenditures).18 Despite many researches has focused on this issue, however, effective solutions to reduce the medical expenditure of older population are still pending. Our study used the NHI claims database to analyze the ambulatory care utilization patterns of the elderly people in Taiwan. To
Table 3 Top 10 primary diagnoses of elderly ambulatory care visits among older people in Taiwan under the National Health Insurance in 2004 Diagnosis
Code range Number of visits in ICD-9-CM (%, n ¼ 57,101,420)
Diseases of the circulatory system Diseases of the respiratory system Diseases of the musculoskeletal system and connective tissue Diseases of the nervous system and sense organs Endocrine, nutritional, and metabolic diseases and immunity disorders Diseases of the digestive system Symptoms, signs, and ill-defined conditions Supplementary classification of factors influencing health status and contact with health services Diseases of the genitourinary system Diseases of the skin and subcutaneous tissue Other diagnosis
390e459 460e519 710e739
9,864,098 (17.3) 9,103,118 (15.9) 7,325,556 (12.8)
320e389
5,877,564 (10.3)
240e279
4,079,607 (7.1)
520e579 780e799 V01eV82
3,881,270 (6.8) 3,061,309 (5.4) 2,585,908 (4.6)
580e629 680e709
2,575,110 (4.5) 2,507,234 (4.4) 6,240,646 (10.9)
ICD-9-CM ¼ International Classification of Diseases, Ninth Revision, Clinical Modification.
(4.7) (16.3) (28.3) (21.4) (12.7) (14.7) (1.9)
(8.3) (21.5) (28.6) (18.2) (10.0) (11.8) (1.6)
(5.5) (19.1) (29.5) (20.4) (11.5) (12.5) (1.5)
the best of our knowledge, our study is the first nationwide study using such extensive computerized database to analyze the ambulatory utilization pattern of a country’s elderly population. Unlike the national database of ambulatory care visits of the United States, which was the sampling survey of the National Ambulatory Medical Care Survey and the National Hospital Ambulatory Medical Care Survey from all states, our database was the complete whole ambulatory care visits of older population in Taiwan without sampling. Thus, our analyses and results were more accurate and less biased than the sampling data set. Our result will provide useful information to our government and health policy makers. Our result demonstrated that elderly beneficiaries in Taiwan had a significantly higher average annual ambulatory visits numbers (26.83 visits) when compared with the data from the United States, Canada, and United Kingdom, that the mean annual visit number of elderly people was only 7.06 times,19 10.2 times,20 and 4.93 times,21 respectively. In addition, nearly one-half (45.9%) of the old beneficiaries in Taiwan had more then 24 ambulatory visits annually. The high frequency of annual ambulatory visit suggested that Taiwan’s NHI has good availability and accessibility of medical care services for older population. Low copayment of ambulatory visit and free access to any health care facilities without restriction of referral might also contribute to this high frequency of ambulatory visits.16 Older women tend to use more health care services and spend more health care expenditure than men because of the increase incidence of postmenopausal-related disease, such as cerebral vascular disease, breast cancer, or osteoporosis in their longer life span.22e24 Our results were consistent with previous reports that female beneficiaries used ambulatory care facilities more frequently than male. However, our results showed that female had a lower mean medical expense per visit than male beneficiaries. One population-based study conducted at Ontario, Canada indicated that old male use expensive examination, such as computed tomography scan and magnetic resonance imaging more often than female,25 and this might provide some possible clues. However, further studies are needed to clarify this phenomenon. Most previous studies indicated that increasing age is associated with increased utilization of health care service.25e28 However, our result revealed that the middle-old age group (age from 75 years to 84 years) had a higher mean annual ambulatory visit numbers and higher mean medical expense per visit than the old-old age group (age above 85 years). This may be because of middle-old elderly usually has better physical strength and ambulatory ability than the old-old elderly. When health care services are cheap and easy to be accessed, middle-old people may use them more often, especially when mild diseases occur. Moreover, the possible explanation for the lower mean medical expense for the old-old elderly is that physicians and family tend to have less invasive and more conservative medical procedures and considering little or no harm for these very old elderly.29 Our findings implied that the health care of middle-old age population needs to be paid more attention by our government’s health policy makers.
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Y.-T. Lin et al. / Journal of Clinical Gerontology & Geriatrics 2 (2011) 53e57
Table 4 Comparison of the three most common primary diagnosis by ICD-9-CM code and accounted percentage distribution between different age groups in Taiwan and United States Country and age group
First common diagnosis
%
Second common diagnosis
%
Third common diagnosis
%
Taiwan 2004 65e74 yr old 75e84 yr old S85 yr old
Acute upper airway infection Essential hypertension Essential hypertension
7.2 6.7 6.4
Essential hypertension Acute upper airway infection Acute upper airway infection
6.6 5.8 5.5
Diabetes mellitus Diabetes mellitus Hypertensive heart disease
5.8 4.8 3.4
8.5 8.1
Diabetes mellitus Heart disease excluding ischemia
6.0 5.3
Arthropathies and related disorders Diabetes mellitus
4.3 4.3
United States 2001e200230 65e74 yr old Essential hypertension S75 yr old Essential hypertension
ICD-9-CM ¼ International Classification of Diseases, Ninth Revision, Clinical Modification.
The three most frequent principal diagnoses of ambulatory visits in Taiwan were diseases of the circulatory system, diseases of the respiratory system, and diseases of the musculoskeletal system and connective tissue, which accounted for 46% of all principal diagnoses. Health education and preventive actions to elderly patients with these chronic diseases are needed. Furthermore, “ambulatory visit with mild diseases” was another issue of elderly people in Taiwan. In 2004, acute upper airway infection (ICD9-CM: 465) was the leading primary diagnosis in the young- old age group and secondary most common diagnosis both in middle-old and old-old age groups. When comparing with the United States data, in 2001e2002, the three most common diagnosis of ambulatory care visit in young-old age group were essential hypertension (8.5%), diabetes mellitus (6.0%), and arthropathies and related disorders (4.3%), whereas essential hypertension (8.1%), heart disease excluding ischemia (5.3%) and diabetes mellitus (4.3%) were the three most common diagnoses in middle-old and old-old age groups.30 (Table 4) In Sweden, the three most common diagnoses of ambulatory care visits for elderly people were hypertension (14.6%), diabetes mellitus (8.9%), and heart failure (6.7%).26 The possible cause of this phenomenon is the low and fixed copayment of NHI ambulatory care visit in Taiwan (from 1.56 to 11.25 USD per visit, depending on the level of health care facility) as well as the low pharmacy copayment (from 0 to 6.25 USD per visit, depending on the total cost of drugs). Higher copayment of ambulatory visits was proved to reduce ambulatory visits in old population. However, it would increase the numbers of hospital admissions in old population.31 So the pros and cons of low copayments of ambulatory visit in Taiwanese NHI need further evaluations. The strength of our study was the completely nationwide computerized database, which contained almost all of the medical practice in Taiwan. Previous health care utilization reports were mostly based on sampling population with interviews or selfreport data, which may have small sample size and easy to have manual errors. In addition, we made the comparison of health care utilization among different old age groups, which was seldom reported in previous researches. However, there were some potential limitations in our study. First, our study did not include those beneficiaries who had not used ambulatory care services. However, because 96.6% elderly beneficiaries had used NHI ambulatory health service and were included in our study, we think our study still has good representativeness of the current patterns of ambulatory health care in older population. Secondary, we did not include the dentistry and traditional Chinese medicine ambulatory care visit data for analysis. Exclusion of these services leads to underestimation of overall utilization of the ambulatory care services. Thirdly, our study did not, however, address the patterns of drug prescription and laboratory test use in elderly ambulatory care service. Further researches are needed to disclose these important issues In conclusion, the mean frequency of ambulatory visits of older people in Taiwan was high, especially in the middle-old age group.
Health education and preventive services should focus on circulatory, respiratory, and musculoskeletal diseases, which accounted for nearly one-half of the primary diagnoses of old age ambulatory visits. Acknowledgments The authors have indicated that they have no conflict of interest with regard to the content of this article. This study is based on data from the National Health Insurance Research Database provided by the Bureau of National Health Insurance, Department of Health and managed by National Health Research Institutes in Taiwan. The interpretation and conclusions contained herein do not represent those of Bureau of National Health Insurance, Department of Health, or National Health Research Institutes. References 1. Centers of Disease Control and Prevention. Public health and aging: trends in agingdUnited States and worldwide. JAMA 2003;289:1371e3. 2. Evans JG. Long term care in later life. BMJ 1995;311:644. 3. Lubitz J, Cai L, Kramarow E, Lentzner H. Health, life expectancy, and health care spending among the elderly. N Engl J Med 2003;349:1048e55. 4. Schellhorn M, Stuck AE, Minder C, Beck JC. Health services utilization of elderly Swiss: evidence from panel data. Health Econ 2000;9:533e45. 5. US Census Bureau. Statistical abstract of the United States: 2010. 129th ed. Washington, DC: US Census Bureau. Available from: http://www.census.gov/ statab/www/; 2009 [accessed 07.03.10]. 6. OECD (Organization for Economic Co-operation and Development). OECD health data 2009. Paris, UK: OECD; 2009. 7. Adams WL, McIlvain HE, Lacy NL, Magsi H, Crabtree BF, Yenny SK, et al. Primary care for elderly people: why do doctors find it so hard? Gerontologist 2002;42: 835e42. 8. Middleton K, Hing E, Xu J. National hospital ambulatory medical care survey: 2005 outpatient department summary. Adv Data 2007;389:1e34. 9. Cherry DK, Woodwell DA, Rechtsteiner EA. National ambulatory medical care survey: 2005 summary. Adv Data 2007;387:1e39. 10. Department of Internal Affairs, Executive Yuan Taiwan. Table 15. Percentage of population for ages 65 and over by selected countries. Available from: http:// www.moi.gov.tw/stat/english/interior.asp [accessed 07.03.10]. 11. Cheng SH, Chiang TL. The effect of universal health insurance on health care utilization in Taiwan. Results from a natural experiment. JAMA 1997;278:89e93. 12. Bureau of National Health Insurance. Insurance coverage. Available from: http:// www.nhi.gov.tw/english/webdata.asp?menu¼11&menu_id¼296&webdata_id¼ 1399 [accessed 07.03.10]. 13. National Health Insurance Research Database. Available from: http://www. nhri.org.tw/nhird/ [accessed 07.03.10]. 14. Su TP, Chen TJ, Hwang SJ, Chou LF, Fan AP, Chen YC. Utilization of psychotropic drugs in Taiwan: an overview of outpatient sector in 2000. Zhonghua Yi Xue Za Zhi (Taipei) 2002;65:378e91. 15. Chen TJ, Chou LF, Hwang SJ. Application of a data-mining technique to analyze coprescription patterns for antacids in Taiwan. Clin Ther 2003;25:2453e63. 16. Chen TJ, Chou LF, Hwang SJ. Patterns of ambulatory care utilization in Taiwan. BMC Health Serv Res 2006;6:54. 17. US Census Bureau. The statistical abstract of the United States. Washington, DC: US Census Bureau; 2009. p. 96e9. 18. Bureau of National Health Insurance. Statistical annual report. Available from: http://www.nhi.gov.tw/english/webdata.asp?menu¼11&menu_id¼296& Cmenu_ID¼311&webdata_id¼1942; 2007 [accessed 07.03.10]. 19. National Center for Health Statistics. Health, United States, 2006 with chart book on trends in the health of Americans. Washington, DC: National Center for Health Statistics; 2006. p. 110e11.
Y.-T. Lin et al. / Journal of Clinical Gerontology & Geriatrics 2 (2011) 53e57 20. Nie JX, Wang L, Shawn C, Moineddin R, Upshur RE. A population-based cohort study of ambulatory care service utilization among older adults. J Eval Clin Pract 2010;16:825e31. 21. Kennerfalk A, Ruigómez A, Wallander MA, Wilhelmsen L, Johansson S. Geriatric drug therapy and healthcare utilization in the United Kingdom. Ann Pharmacother 2002;36:797e803. 22. Owens GM. Gender difference in health care expenditures, resource utilization and quality of life. J Manag Care Pharm 2008;14:S2e6. 23. Muller CL. Health care and gender. New York, NY: Russell Sage Foundation; 1990. 24. Verbrugge LM. A health profile of older women with comparisons to older men. Res Aging 1984;6:291e322. 25. Nie JX, Wang L, Shawn C, Moineddin R, Upshur RE. Health care service utilization among the elderly: findings from the Study to Understand the Chronic Condition Experience of the Elderly and the Disabled (SUCCEED project). J Eval Clin Pract 2008;14:1044e9.
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26. Jörgensen T, Johansson S, Kennerfalk A, Wallander MA, Svärdsudd K. Prescription drug use, diagnoses, and healthcare utilization among the elderly. Ann Pharmacother 2001;35:1004e9. 27. Denton FT, Gafni A, Spencer BG. Exploring the effects of population change on costs of physician servicees. J Health Econ 2002;21:781e803. 28. Wolinsky FD, Mosely II RR, Coe RM. A cohort analysis of the use of health services by elderly Americans. J Health Soc Behav 1986;27:209e19. 29. Callahan D. Health care for the elderly: policy demands and individual needs. Am J Geriatr Cardiol 1999;8:300e3. 30. Schappert SM, Burt CW. Ambulatory care visits to physician offices, hospital outpatient departments, and emergency departments: United States, 2001e02. National Center for Health Statistics. Vital Health Stat 2006;13: 1e66. 31. Trivedi AN, Moloo H, Mor V. Increase ambulatory care copayments and hospitalizations among the elderly. N Engl J Med 2010;362:320e8.
Contents lists available at ScienceDirect
Journal of Clinical Gerontology & Geriatrics journal homepage: www.e-jcgg.com
Original article
Ambulatory health care utilization of the older people under the National Health Insurance in Taiwan Yi-Tsong Lin, MD a, b, c, Shinn-Jang Hwang, MD b, c, *, Liang-Kung Chen, MD b, c, Tzeng-Ji Chen, MD, PhD b, c, I-Hsuan Hwang, BA d a
Banchiao Veterans Home, Taipei County, Taiwan Department of Family Medicine, Center for Geriatrics and Gerontology, Taipei Veterans General Hospital, Taipei, Taiwan Department of Family Medicine, National Yang Ming University School of Medicine, Taipei, Taiwan d Department of Business Administration, Shin-Chien University, College of Management, Taipei, Taiwan b c
a r t i c l e i n f o
a b s t r a c t
Article history: Received 20 August 2010 Received in revised form 28 December 2010 Accepted 30 January 2011
Background/Purpose: To analyze and describe the patterns of ambulatory care utilization by the older people within the Taiwanese National Health Insurance (NHI) program. Methods: The nationwide computerized claims database of elderly ambulatory care visits under the NHI in 2004 was accessed. We obtained the complete outpatients service claim data sets of Western medicine for beneficiaries S 65 years old. We then analyzed the pattern and frequency of visits by patient age, sex, and primary diagnosis. Results: In 2004, 96.6% of all elderly NHI beneficiaries had ever used ambulatory care service and there were totally 57,101,420 ambulatory care visits records from these elderly beneficiaries. The average ambulatory visit number of each beneficiary is 26.8 22.7 (mean standard deviation) times per year, which was much higher than United States and other Organization for Economic Co-operation and Development countries. Nearly one-half of the elderly had more than 24 times visits annually. Female beneficiaries had higher average annual ambulatory visit number but lower mean medical expense per visit than male beneficiaries. The middle old age group (75e84 years old) had highest average visits numbers (29.2 23.3) and highest average medical expense per visit: 37.1 US dollar. The three most frequent principal diagnoses of elderly ambulatory visits were diseases of the circulatory system (17.3%), diseases of the respiratory system (15.9%), and diseases of the musculoskeletal system and connective tissue (12.8%), respectively. While compared with United States data, the proportion of acute upper airway infection was much higher among old age ambulatory visits in Taiwan. Conclusion: The mean frequency of ambulatory visits of older people in Taiwan was high, especially in the middle-old age group. Health education and preventive services should focus on circulatory, respiratory, and musculoskeletal diseases, which accounted for nearly one-half of the primary diagnoses of old age ambulatory visits. Copyright Ó 2011, Asia Pacific League of Clinical Gerontology & Geriatrics. Published by Elsevier Taiwan LLC. All rights reserved.
Keywords: Ambulatory care visits Elderly Health care utilization Medical expense National Health Insurance
1. Introduction The world population is aging now. With the decrease in birth rate and prolonged life expectancy, almost every country has an increasing elderly population.1e3 However, living longer means there are more chances to suffer from acute or chronic illness.
* Corresponding author. Department of Family Medicine, Center for Geriatrics and Gerontology, Taipei Veterans General Hospital, No. 201, Shih-Pai Road, Section 2, Taipei 11217, Taiwan. E-mail address: [email protected] (S.-J. Hwang).
Previous studies proved that old age population usually accounts for the biggest proportion of a country’s health care cost while comparing with young age groups.4,5 But there are very few published studies evaluating the health care resources utilization between different old age groups, which is also very important. Furthermore, ambulatory health care accounts for most health care expenditure in most countries.6 In United State, people aged 65 and older account for 30%e40% of primary care physician visits.7e9 So if we want to look into the issue of increasing health cost in one country and try to find out some possible solutions, the ambulatory health care utilization by the elderly population must be studied and analyzed.
2210-8335/$ e see front matter Copyright Ó 2011, Asia Pacific League of Clinical Gerontology & Geriatrics. Published by Elsevier Taiwan LLC. All rights reserved. doi:10.1016/j.jcgg.2011.03.002
54
Y.-T. Lin et al. / Journal of Clinical Gerontology & Geriatrics 2 (2011) 53e57
As in many developed countries, Taiwan’s society has a dramatic shift under way toward a graying population. Till the end of 2007, 10.2% of total Taiwan population were aged 65 years and older, and the percentage is still increasing rapidly.10 The Taiwanese National Health Insurance (NHI) program, a social health insurance, provides universal coverage to most inhabitants. Beneficiaries can obtain medical services at the clinic or hospital by their choice without a referral. The purpose of our study was to describe and analyze the patterns of ambulatory care visit of elderly people in Taiwan within the NHI in 2004. We focused on the frequency and diagnoses of ambulatory visits and tried to analyze the difference between different old age groups. We hoped the findings might provide some evidence for health policymaking.
3. Results 3.1. General information of the study In 2004, all beneficiaries had a total of 57,101,420 ambulatory care visits. There were totally 2,128,388 beneficiaries who had ever used NHI ambulatory care service, equivalent to 96.6% of all elderly beneficiaries. Among them, 1,056,902 (49.7%) were male and 1,059,936 (49.8%) were female. If divided by age groups, 1,254,413 (58.9%) subjects belonged to young-old age group, 723,774 (34.0%) subjects, and 150,201 (7.1%) subjects belonged to middle-old age group and old-old age group, respectively. 3.2. Visits frequency and medical expense by sex and age group
2. Methods 2.1. Data source and study design The data source of this study mainly come from the National Health Insurance Research Database (NHIRD) project of the National Health Research Institute. The NHI program was initiated in Taiwan since 1995. It is a universal insurance program and covers nearly all inhabitants (at the end of 2004, it had 97.6% coverage rate) in Taiwan.11,12 In 1999, the Bureau of National Health Insurance began to release all claims data in electronic form to the public under the project of NHIRD. The details about the NHI program and the structure of the claims data sets are described on the NHIRD Web site13 and in our previous publications.14e16 In this study, we obtained the complete outpatients service claims data sets of beneficiaries aged S65 years old (CD2004.DAT) from NHIRD. These data sets contained the ambulatory care clinics and emergency department visiting files, including dates, medical care facilities and physicians’ specialties, patients’ genders, dates of birth, the three major diagnoses coded in the International Classification of Disease, Ninth Revision, Clinical Modification (ICD-9-CM) format and the medical expense (contains the drug fee; medical procedures, including laboratory tests and roentgenographic examinations; treatment and medical supply; diagnosis fee; and pharmacy dispensing service fee, physician charge is not included.) of each visit from all medical care institutions under contract with the Bureau of National Health Insurance in Taiwan. To protect privacy, data identifying patients had been scrambled cryptographically. Among all old age ambulatory visit records in 2004, we only took the Western medicine outpatients service data for analyses, emergency visits of older population were not analyzed. We at first divided all beneficiaries into three different age groups: the youngold age group (65e74 years old), middle-old age group (75e84 years old) and old-old age group (85 years old and older). Then, we calculated the mean annual outpatients service visit numbers and mean medical expense per visit among different age groups. To investigate the relationship between age and visits frequency, we calculated each beneficiary’s annual visits numbers and displayed both in numbers of visits and in numbers of patients by different age groups. We also calculated the frequency distribution of principal diagnoses at all visits by ICD-9-CM chapter. 2.2. Statistical methods The database software of Microsoft SQL Server 2008 (Microsoft Corp., Redmond, WA, USA) was used for data linkage and processing. Descriptive data are presented in the text and tables, including frequencies, numbers, percentages, and means. The regular statistics were displayed as mean standard deviation (mean SD).
In 2004, each elderly beneficiary had an average of 26.8 ambulatory visits annually. Female beneficiaries had higher mean frequency of ambulatory visits but lower mean medical expense per visit than male [26.2 21.2 times vs. 24.9 22.1 times; 35.9 United States Dollar (USD) vs. 37.3 USD]. When analyzing among different old age groups, the middle old age group had the highest mean frequency of ambulatory visit (29.2 23.3 times), followed by young-old age group (25.7 21.3 times), and old-old age group (25.2 22.8 times) (Table 1). The mean medical expense per ambulatory visit was 36.8 USD (range: 0e16,368 USD). When comparing among three age groups, the old-old age group had the lowest mean medical expense per visit (34.0 USD, range: 0e8331 USD), followed by young- and middle-old age group. The most frequent number of annual ambulatory visits was 13e24 times per year (1e2 times per month), followed by 25e36 times per year (2e3 times per month), 3e12 times, 49e96 times, and 37e48 times per year. Near one-half (45.9%) of all beneficiaries had ever visited ambulatory clinics more than 24 times annually (Table 2). More than one-half of middle age elderly (50.7%) had a mean ambulatory visits more than 24 times per year, higher than 43.8% in young-old elderly and 41.6% in the old-old elderly. 3.3. Distribution of ambulatory care visits by principal diagnosis Diseases of the circulatory system (n ¼ 9,864,098; 17.3%), diseases of the respiratory system (n ¼ 9,103,118; 15.9%), and diseases of the musculoskeletal system and connective tissue (n ¼ 7,325,556; 12.8%) were the top three primary diagnosis of elderly ambulatory visits (Table 3). Almost one-half of all visits had either one of these three diseases as the principal diagnosis. If we analyzed the primary diagnosis of ambulatory care visits among
Table 1 The mean annual visit numbers and mean medical expense per visit by gender and age groups among older people in Taiwan under the National Health Insurance in 2004 Mean annual visit numbers per persona
Mean medical expense per visitb
Gender Male Female
24.9 22.1 26.2 21.2
37.3 35.9
Age group 65e74 yr old 75e4 yr old S85 yr old All age
25.7 21.3 29.2 23.3 25.2 22.8 26.8 22.7
36.9 37.1 34.0 36.8
Gender and age group
a
Data were expressed with mean standard deviation. Medical expense ¼ Drug fee þ medical procedures, including laboratory tests and roentgenographic examinations þ treatment and medical supply þ diagnosis fee þ pharmacy dispensing service fee in US Dollars. b
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Table 2 Distribution of the beneficiary’s ambulatory visit frequency by different age groups Number of visit in 2004 per person
65e74 yr old, n (%) (n ¼ 12,54,413)
75e84 yr old, n (%) (n ¼ 723,774)
S85 yr old, n (%) (n ¼ 150,201)
All age, n (%) (n ¼ 21,28,388)
<3 3e12 13e24 25e36 37e48 49e96 >96
70,778 255,542 378,985 253,421 137,890 141,773 16,064
34,244 117,337 204,938 154,329 92,134 106,722 14,070
12,410 32,282 43,031 27,309 15,069 17,676 2424
117,432 405,161 626,954 435,059 245,093 266,171 32,558
(5.6) (20.4) (30.2) (20.2) (11.0) (11.3) (1.3)
three old age groups, the three most frequent diagnoses of youngold age group were acute upper airway infection (ICD-9-CM code: 465, accounted for 7.2% of total young-old population), essential hypertension (ICD-9-CM code: 401, 6.6% of total young-old population), and diabetes mellitus (ICD-9-CM code: 250, 5.8% of total young-old population), whereas in the middle-old age group, they were essential hypertension (6.7%), acute upper airway infection (5.8%), and diabetes mellitus (4.8%), and in old-old age group, they were essential hypertension(6.4%), acute upper airway infection (5.5%), and hypertensive heart disease (ICD-9-CM code: 401, 3.4%), respectively (Table 4). 4. Discussion Taiwan, like many other countries, is facing an increasing elderly population, and the increase in old age population has become the biggest burden of a country’s health care system. In United States, the average annual health care expenditure of the elderly people was increased from 2200 USD per person in 1991 to 4300 USD per person in 2006.17 In Taiwan, the number of elderly population has accounted for 10.4% of total population, but accounted for 39.3% of total medical expenditure.18 Among the total medical expenditure, ambulatory care service accounts for the major part (9.04 billion USD for ambulatory care service, equivalent to 65.7% to total health care expenditures).18 Despite many researches has focused on this issue, however, effective solutions to reduce the medical expenditure of older population are still pending. Our study used the NHI claims database to analyze the ambulatory care utilization patterns of the elderly people in Taiwan. To
Table 3 Top 10 primary diagnoses of elderly ambulatory care visits among older people in Taiwan under the National Health Insurance in 2004 Diagnosis
Code range Number of visits in ICD-9-CM (%, n ¼ 57,101,420)
Diseases of the circulatory system Diseases of the respiratory system Diseases of the musculoskeletal system and connective tissue Diseases of the nervous system and sense organs Endocrine, nutritional, and metabolic diseases and immunity disorders Diseases of the digestive system Symptoms, signs, and ill-defined conditions Supplementary classification of factors influencing health status and contact with health services Diseases of the genitourinary system Diseases of the skin and subcutaneous tissue Other diagnosis
390e459 460e519 710e739
9,864,098 (17.3) 9,103,118 (15.9) 7,325,556 (12.8)
320e389
5,877,564 (10.3)
240e279
4,079,607 (7.1)
520e579 780e799 V01eV82
3,881,270 (6.8) 3,061,309 (5.4) 2,585,908 (4.6)
580e629 680e709
2,575,110 (4.5) 2,507,234 (4.4) 6,240,646 (10.9)
ICD-9-CM ¼ International Classification of Diseases, Ninth Revision, Clinical Modification.
(4.7) (16.3) (28.3) (21.4) (12.7) (14.7) (1.9)
(8.3) (21.5) (28.6) (18.2) (10.0) (11.8) (1.6)
(5.5) (19.1) (29.5) (20.4) (11.5) (12.5) (1.5)
the best of our knowledge, our study is the first nationwide study using such extensive computerized database to analyze the ambulatory utilization pattern of a country’s elderly population. Unlike the national database of ambulatory care visits of the United States, which was the sampling survey of the National Ambulatory Medical Care Survey and the National Hospital Ambulatory Medical Care Survey from all states, our database was the complete whole ambulatory care visits of older population in Taiwan without sampling. Thus, our analyses and results were more accurate and less biased than the sampling data set. Our result will provide useful information to our government and health policy makers. Our result demonstrated that elderly beneficiaries in Taiwan had a significantly higher average annual ambulatory visits numbers (26.83 visits) when compared with the data from the United States, Canada, and United Kingdom, that the mean annual visit number of elderly people was only 7.06 times,19 10.2 times,20 and 4.93 times,21 respectively. In addition, nearly one-half (45.9%) of the old beneficiaries in Taiwan had more then 24 ambulatory visits annually. The high frequency of annual ambulatory visit suggested that Taiwan’s NHI has good availability and accessibility of medical care services for older population. Low copayment of ambulatory visit and free access to any health care facilities without restriction of referral might also contribute to this high frequency of ambulatory visits.16 Older women tend to use more health care services and spend more health care expenditure than men because of the increase incidence of postmenopausal-related disease, such as cerebral vascular disease, breast cancer, or osteoporosis in their longer life span.22e24 Our results were consistent with previous reports that female beneficiaries used ambulatory care facilities more frequently than male. However, our results showed that female had a lower mean medical expense per visit than male beneficiaries. One population-based study conducted at Ontario, Canada indicated that old male use expensive examination, such as computed tomography scan and magnetic resonance imaging more often than female,25 and this might provide some possible clues. However, further studies are needed to clarify this phenomenon. Most previous studies indicated that increasing age is associated with increased utilization of health care service.25e28 However, our result revealed that the middle-old age group (age from 75 years to 84 years) had a higher mean annual ambulatory visit numbers and higher mean medical expense per visit than the old-old age group (age above 85 years). This may be because of middle-old elderly usually has better physical strength and ambulatory ability than the old-old elderly. When health care services are cheap and easy to be accessed, middle-old people may use them more often, especially when mild diseases occur. Moreover, the possible explanation for the lower mean medical expense for the old-old elderly is that physicians and family tend to have less invasive and more conservative medical procedures and considering little or no harm for these very old elderly.29 Our findings implied that the health care of middle-old age population needs to be paid more attention by our government’s health policy makers.
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Table 4 Comparison of the three most common primary diagnosis by ICD-9-CM code and accounted percentage distribution between different age groups in Taiwan and United States Country and age group
First common diagnosis
%
Second common diagnosis
%
Third common diagnosis
%
Taiwan 2004 65e74 yr old 75e84 yr old S85 yr old
Acute upper airway infection Essential hypertension Essential hypertension
7.2 6.7 6.4
Essential hypertension Acute upper airway infection Acute upper airway infection
6.6 5.8 5.5
Diabetes mellitus Diabetes mellitus Hypertensive heart disease
5.8 4.8 3.4
8.5 8.1
Diabetes mellitus Heart disease excluding ischemia
6.0 5.3
Arthropathies and related disorders Diabetes mellitus
4.3 4.3
United States 2001e200230 65e74 yr old Essential hypertension S75 yr old Essential hypertension
ICD-9-CM ¼ International Classification of Diseases, Ninth Revision, Clinical Modification.
The three most frequent principal diagnoses of ambulatory visits in Taiwan were diseases of the circulatory system, diseases of the respiratory system, and diseases of the musculoskeletal system and connective tissue, which accounted for 46% of all principal diagnoses. Health education and preventive actions to elderly patients with these chronic diseases are needed. Furthermore, “ambulatory visit with mild diseases” was another issue of elderly people in Taiwan. In 2004, acute upper airway infection (ICD9-CM: 465) was the leading primary diagnosis in the young- old age group and secondary most common diagnosis both in middle-old and old-old age groups. When comparing with the United States data, in 2001e2002, the three most common diagnosis of ambulatory care visit in young-old age group were essential hypertension (8.5%), diabetes mellitus (6.0%), and arthropathies and related disorders (4.3%), whereas essential hypertension (8.1%), heart disease excluding ischemia (5.3%) and diabetes mellitus (4.3%) were the three most common diagnoses in middle-old and old-old age groups.30 (Table 4) In Sweden, the three most common diagnoses of ambulatory care visits for elderly people were hypertension (14.6%), diabetes mellitus (8.9%), and heart failure (6.7%).26 The possible cause of this phenomenon is the low and fixed copayment of NHI ambulatory care visit in Taiwan (from 1.56 to 11.25 USD per visit, depending on the level of health care facility) as well as the low pharmacy copayment (from 0 to 6.25 USD per visit, depending on the total cost of drugs). Higher copayment of ambulatory visits was proved to reduce ambulatory visits in old population. However, it would increase the numbers of hospital admissions in old population.31 So the pros and cons of low copayments of ambulatory visit in Taiwanese NHI need further evaluations. The strength of our study was the completely nationwide computerized database, which contained almost all of the medical practice in Taiwan. Previous health care utilization reports were mostly based on sampling population with interviews or selfreport data, which may have small sample size and easy to have manual errors. In addition, we made the comparison of health care utilization among different old age groups, which was seldom reported in previous researches. However, there were some potential limitations in our study. First, our study did not include those beneficiaries who had not used ambulatory care services. However, because 96.6% elderly beneficiaries had used NHI ambulatory health service and were included in our study, we think our study still has good representativeness of the current patterns of ambulatory health care in older population. Secondary, we did not include the dentistry and traditional Chinese medicine ambulatory care visit data for analysis. Exclusion of these services leads to underestimation of overall utilization of the ambulatory care services. Thirdly, our study did not, however, address the patterns of drug prescription and laboratory test use in elderly ambulatory care service. Further researches are needed to disclose these important issues In conclusion, the mean frequency of ambulatory visits of older people in Taiwan was high, especially in the middle-old age group.
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