- Email: [email protected]
Direct medical costs in patients with Alzheimer's disease in Taiwan: A population-based study
CURRENT THERAPEUTIC RESEARCH VOLUME 70, NUMBER I, FEBRUARY 2009
Direct Medical Costs in Patients With Alzheimer's Disease in Taiwan: A Population-Based Study Agnes i.E Chan, MAMM1,2; Thau-Ming Cham, PhD 1; and Shun-Jin Lin, PhDl
lSchool o/Pharmacy, Kaohsiung Medical University, Kaohsiung, Taiwan; and 2 Chi Mei Medical Center, Tainan, Taiwan
ABSTRACT BACKGROUND: Alzheimer's disease (AD) has the potential to become a major health concern and associated health care costs may become a significant economic burden on society. OBJECTIVE: The aim of this study was to estimate the direct medical costs attributable to AD in patients aged ::0-60 years in Taiwan from 2000 through 2002 and to explore the correlation of these costs with patients' age and sex. METHODS: This study was based on the National Health Insurance Research Database of Taiwan's National Health Insurance (NHI) program. The NHI program insures >98% of the 23 million inhabitants of Taiwan. Detailed data were extracted from a random sample of 0.2% of inpatient and 5% of outpatient recipients with AD (International Classification 0/ Diseases, Ninth Revision, Clinical Modification diagnosis code 331.0) who were aged ::0-60 years and who received inpatient or outpatient services with claims from January 1,2000, to December 31, 2002. Duplicate charges for a specific patient and diagnoses of other types of dementia were excluded from this study. RESULTS: A total of 69,780 patients were found to have a diagnosis of AD. The direct medical costs for outpatients were estimated at US $1.2 million in 2000, US $1.9 million in 2001, and US $2.3 million in 2002; the costs for inpatient care were estimated at US $670,000 in 2000, US $2.4 million in 2001, and US $3.2 million in 2002. The total direct medical costs were estimated at US $1.86 million in 2000, US $4.24 million in 2001, and US $5.48 million in 2002. The increase of total direct medical costs was not significantly correlated with patients' age or sex. CONCLUSIONS: From 2000 through 2002, the direct medical costs of AD increased annually in Taiwan among patients with AD aged ::0-60 years. No significant correlation was found between increased total direct medical costs and sex or age. The cost estimate presented here has implications for future decision making about reallocating medical resources for treating AD in Taiwan. (Curr Ther Res Clin Exp. 2009; 70:10-18) © 2009 Excerpta Medica Inc. KEY WORDS: Alzheimer's disease, direct medical costs, Taiwan. Accepted for publication October 24, 2008. © 2009 Excerpta Medica Inc. All rights reserved.
10
doi: 10.1 0 16/j .curtheres.2009 .02 .005 001l-393X/$ - see front matter
A.L.F. CHAN ET AL.
INTRODUCTION
The prevalence of Alzheimer's disease (AD) in persons aged ::0-65 years has been estimated to be 2% to 10% in the United States and 3.3% to 6.0% in Europe. 1 In east Asia, the prevalence of AD has been estimated to be ~4.8% in China,2 2.1% in Japan,3 and 2% to 4% in Taiwan. 4- 7 The number of people with AD in these countries is increasing gradually as the population ages. s AD has the potential to become a major health concern and associated health care costs may become a significant burden worldwide. The estimate of the worldwide direct costs of AD and dementia care was increased from US $156 billion in 2003 9 to US $315 billion in 2005 10 annually and is projected to nearly double by 2025 to 600 billion.7,10 Care of individuals with AD and dementia consists of formal and informal care. The patterns of care differ throughout the world because of differences in cultures, families, care organizations, and financing. Some researchers assumed that 73% of people with dementia in developed countries lived at home and received 1.6 hours per day of informal care to assist with the personal activities of daily life. 10 However, determining the cost of informal care is a controversial and complicated issue. 1o In Taiwan, as in many other countries, families are the main caregivers to older AD patients who are no longer able to care for themselves. l l Such individuals usually require constant supportive care at home or in a nursing home (informal care) to improve their basic and instrumental activities of daily living and medical treatment (formal care).12 The costs of formal and informal care in patients with AD are high and are related to disease severity and the presence of behavioral disturbances. 13 - 15 A pilot study in Taiwan concluded that families with higher accessibility to nursing homes were willing to pay US $174 per month more than caregivers with lower accessibility.16 Family caregivers who are aged> 65 years, have more than a high school education, have a higher family income, and have easy accessibility to nursing home services were likely to attach higher economic value to nursing home placement. The economic and social burden of AD may become a major health care problem in Taiwan. However, to date, research analyzing the costs of AD in Taiwan has not been published. This is the first pilot study to assess the direct medical costs of AD in Taiwan to provide the National Health Insurance (NHI) program with economic data needed to make decisions about reallocating medical resources and establishing preventive care for the aging population. METHODS DATA SOURCE
Institutional review board approval was not required for this study because all personal data were kept confidential by the NHI. This study used a top-down approach based on the National Health Insurance Research Database (NHIRD) of Taiwan's NHI program. Data were extracted from a random sample of 0.2% inpatient and 5% outpatient insurance recipients with a diagnosis of AD (International Classification of Diseases, Ninth Revision, Clinical Modification [ICD-9-CM} diagnosis code 331.0).17 The sampling percentages were determined
11
CURRENT THERAPEUTIC RESEARCH
by the NHI, which also performed the randomization. The data files contain an original system for sampling claims data, including monthly claim summaries for inpatient claims, ambulatory care claims, inpatient expenditures by admissions, details of inpatient orders, ambulatory care expenditures by visits, details of ambulatory care orders, the primary diagnosis, up to 2 secondary diagnoses (in ICD-9-CM format), and a registry for beneficiaries. The registration file includes a registry for medical services and a registry for drug prescriptions. 1s The NHI program is a comprehensive program that insures >98% of the 23 million inhabitants of Taiwan. The NHIRD data are based on date of payment rather than date of service. The 2000 to 2001 paid claims files were used to create a 1-year file of claims for services provided during 2000; a similar procedure was used for 2001 and 2002 data. Payment for services provided is usually made within 3 months. Therefore, using 1 year of paid claims to create a 1-year file of services would have captured almost all relevant claims. Recipients who had invalid registry data were excluded from this study. The components of direct medical costs include costs of medications and laboratory tests, physicians' fees, pharmacist dispensing fees, room charges, meal service charges, diagnosis examination charges (eg, computed tomography, magnetic resonance imaging, single-photon emission computed tomography, positron emission tomography), supportive treatment charges (eg, psychotherapy), and rehabilitation charges. Total costs were indicated in US dollars using an exchange rate of Taiwan $I = US $32.80. ALZHEIMER'S DISEASE COHORT SELECTION
All NHI recipients who were eligible for ::0-1 day during 2000 and who had only 1 medical claim (NHI does not allow duplicate claims) within 90 days in that year with a primary or secondary diagnosis of AD were included. Diagnoses of other types of dementia (ICD-9-CM codes 290.0, 290.1, 290.10-290.13, 290.2, 290.20, 290.21, 290.3, 290.4, 290.40-290.43, 290.9, 294.9, 332.2, 331.89, 331.9, and 797) and possible duplicate charges for a specific patient within 90 days were also excluded from this study. STUDY MEASURES
Our study was focused on the direct medical costs to the NHI program from 2000 to 2002 for patient care. The direct medical costs for patients with the primary or secondary diagnosis of AD were calculated. STATISTICAL ANALYSIS
Descriptive analyses were conducted for the study cohort of patients with AD, including demographic characteristics, NHI care eligibility status, and months ofNHI care eligibility during 2000. The analyses were intended to describe the characteristics of the AD cohort and to identifY whether age and sex might influence direct medical costs. The differences between total direct medical costs with patients' age and sex were evaluated using the X2 test. The correlation between the increase in total direct medical costs and patients' age and sex were analyzed using Pearson correlation analysis.
12
A.L.F. CHAN ET AL.
RESULTS
A total of 69,780 patients who were aged ::0-60 years with an ICD-9-CM code of 331.0 noted as the primary or secondary diagnosis from 2000 to 2002 in the inpatient and outpatient claims file samples remained after we removed invalid claims, duplicate claims within 3 months in the same year, and persons with an invalid date of birth. Table I shows that 14.57% of patients were aged ::0-80 years, 1.36% were aged 60 to 69 years, 4.38% were aged 70 to 79 years, and 0.0008% were aged <;59 years. There were more female patients than male patients in both the outpatient and inpatient services (data not shown). The direct medical costs for outpatients were estimated at US $1.2 million in 2000, US $1.9 million in 2001, and US $2.3 million in 2002; the costs for inpatient care were estimated at US $670,000 in 2000, US $2.4 million in 2001, and US $3.2 million in 2002. The total direct medical costs for patients with a diagnosis of AD were estimated to be US $1.86 million in 2000, US $4.24 million in 2001, and US $5.48 million in 2002, which were ~0.02%, 0.05%, and 0.05% of the total health care expenditures in Taiwan, respectively (Table II). Expenditures for inpatient and outpatient services increased annually from 2000 to 2002. Mean annual cost per patient was US $1418 in 2000, US $3793 in 2001, and US $5005 in 2002. The increase in inpatient cost in 2000 was ~3.5-fold of that reported in 2001 (Tables III and IV). The cost of medications accounted for 39.4%, 34.4%, and 33.7% of the total direct medical costs claimed in 2000, 2001, and 2002, respectively (Table II). Based on our estimate of total direct medical costs, annual spending by the NHI program for AD is projected to be approximately US $105 million. The correlation between the increases in total direct medical costs and age was not significant; no linear relationship was found. Similarly, the correlation between total direct medical costs and sex was not significant. DISCUSSION
In this pilot study, we estimated the direct medical costs of AD and its correlation with patient sex and the increasing age of the population in Taiwan. Results suggest that the number of women aged> 75 years with AD was higher than that of men at the same age. This result is consistent with some local and Western studies that found that the prevalence of AD was higher in women than men, but the increase in incidence remains a controversial issue. 4 ,7,19,20 The age-adjusted incidence has been found to be higher in women, particularly with advancing age. The total direct medical costs for inpatient and outpatient care increased each year, with the increase being higher for inpatient than outpatient costs. The reason for this discrepancy might be that, in the early stages of AD, patients in Taiwan are generally unaware of their condition and remain at home until the disease becomes more severe and medical treatment is then sought. These results are consistent with the findings of Meek et al 21 that US patients are typically hospitalized in the later stages of AD, resulting in a greater proportion of direct costs for inpatient care. We found that the total direct medical costs and mean annual cost per patient increased from 2000 to 2002. This may be related to physicians using the ICD-9-CM
13
n c
:a :a
/II
z -I
t
Table I. Characteristics of patients in Taiwan with Alzheimer's disease.
/II
:a
:0;59 Years
l>
60-69 Years
"C -I n /II
Male
Female
Male
Female
SG
B*
SG
B*
SG
B*
SG
B*
500 520 0 1020 0.0007
9,349,760 9,419,945 9,497,868 28,267,573
0 20 0 20 0.0001
9,398,296 9,506,836 9,582,575 28,487,707
1020 2020 2520 5560 0.53
693,502 694,596 696,655 2,084,753
3040 3560 1020 7620 0.83
713,519 732,106 745,486 2,191,111
Year
:ll /II
'l>"
/II
2000 2001 2002 Total % of B
70-79 Years Male Year 2000 2001 2002 Total % of B
~80
Female
Years
Male
Female
Total
SG
B*
SG
B*
SG
B*
SG
B*
SG
B*
2620 3640 6180 12,440 1.54
528,131 539,650 545,541 1,613,322
5140 6080 7600 18,820 2.84
424,644 442,545 458,107 1,325,296
1620 5200 5220 12,040 5.28
138,687 151,643 165,147 455,477
2560 2600 7100 12,260 4.91
154,287 166,234 178,099 498,620
16,500 23,640 29,640 60,780 0.15
21,400,826 21,653,555 43,054,381 86,108,762
SG = study group; B = beneficiaries. *Bureau of National Health Insurance, Taiwan.
:a n
:t
Table II. Changes in direct medical costs (US $) associated with Alzheimer's disease in Taiwan claimed from 2000 through 2002.
Year
Total Health Expenditures Claimed (US $ Billion)
Outpatient
2000
9.0
1,190,584.60
672,474.50
1,863,059.10
0.02
734,193
39.4
2001
9.4
1,867,184.60
2,375,273.20
4,242,457.80
0.05
1,459,028
34.4
Direct Medical Costs Claimed Inpatient
Total
% of Total Health Care Expe nd itu res Claimed
Medication Expenses
Medication Portion of Medical Costs Claimed, %
2002
10.3
2,330,369.20
3,151,787.70
5,482,156.90
0.05
1,848,386
33.7
Total
28.7
5,388,138.50
6,199,535.40
11,587,673.00
0.04
4,041,607
34.9
~
r :'I
n
:t l> Z
.. til
/II
-I
l>
r
CURRENT THERAPEUTIC RESEARCH
Table III. Total direct medical costs (US $) associated with Alzheimer's disease for outpatient care in Taiwan. Year
No. of Patients
Total Direct Medical Cost
Mean (SO)
2000 2001 2002 Total
16,000 23,000 29,000 68,000
1,190,584.60 1,867,184.60 2,330,369.20 5,388,138.40
5445.90 (5325.90) 5984.00 (3976.80) 6384.70 (5933.60)
Table IV. Total direct medical costs (US $) associated with Alzheimer's disease for inpatient care in Taiwan. Year
No. of Patients
Total Direct Medical Cost
Mean (SO)
2000 2001 2002 Total
500 640 640 1780
672,474.50 2,375,273.20 3,151,787.70 6,199,535.40
104,514.20 (67,758.70) 333,571.50 (390,811.70) 534,967.60 (567,473.20)
code for AD more accurately or to annual economic inflation. Compared with other countries, the annual direct medical cost per patient reported in the United States was US $7929,22 US $3420 to US $9658 in Argentina,23 US $1766 in Turkey, 1 and US $1058 in China. 24 The costs found in our study were lower than those reported in the Western countries, but higher than the costs in China. Another variable, medication costs, is also associated with direct medical costs. More than 30% of the total direct medical costs for the treatment of AD were for drugs. This finding is lower than the finding in a previous study in which drug costs accounted for 36.0% of total direct medical costs in patients in the early stages of AD22 and an average of 66.0% in patients at all stages of the disease. 1 This may be due to a policy that restricts the global medication budget (the amount is determined by the individual hospital's global budget issued by the Bureau of National Health Insurance in Taiwan).18 The correlation between the increases in total direct medical cost with age and sex of the population was small and no linear relationship was found in our study. However, the effects of age and sex remain of concern in AD, as indicated by the findings of 2 studies conducted in southern Taiwan: one study found age to be a major risk factor for AD4 and the other found that being of female sex was probably an AD risk factor. 19 LIMITATIONS
This study was subject to several limitations that are inherent in investigations that rely on the use of health insurance claims data. 25,26 Patients may have been coded with a diagnosis of AD while in fact they had another form of dementia. Similarly, some patients may have been miscoded as having other forms of dementia that were excluded
16
A.L.F. CHAN ET AL.
from the study. In addition, patients in the early stages of AD, when it is difficult to diagnose, may not have had this diagnosis recorded on the claims files and thus would not have been included in this study. In this pilot study, we did not control for differences in other covariants (eg, major chronic comorbid conditions, other prevalent conditions). Therefore, disease prevalence and costs may have been underestimated. Another limitation of this study was the lack of NHIRD data for disease severity. Consequently, we were unable to estimate the effects of the severity of AD on costs. Therefore, the standard errors of these estimates were large and the coefficients were not statistically significant. The inability to separate AD costs from other costs in AD patients was also a limitation of the study. The increasing number of elderly people poses a challenge for health care providers and countries providing national health care insurance. Further research into the economic burden, including direct and indirect medical costs of AD in Taiwan, is therefore an important priority. CONCLUSIONS From 2000 through 2002, the direct medical costs of AD increased annually in Taiwan among patients with AD aged ::0-60 years. No significant correlation was found between increased total direct medical costs and sex or age. Results from this study should be considered in reallocating limited medical resources for treating AD in Taiwan. REFERENCES 1. Zencir M, Kuzu N, Be§er NG, et al. Cost of Alzheimer·s disease in a developing country setting. Int] Geriatr Psychiatry. 2005;20:616-622. 2. Zhang ZX, Zahner GE, Roman GC, et al. Dementia subtypes in China: Prevalence in Beijing, Xian, Shanghai, and Chengdu. Arch Neurol. 2005;62:447--453. 3. Yamada T, Hattori H, Miura A, et al. Prevalence of Alzheimer·s disease, vascular dementia and dementia with Lewy bodies in a Japanese population. Psychiatry Clin Neurosci. 2001;55:21-25. 4. Lin RT, Lai CL, Tai CT, et al. Prevalence and subtypes of dementia in southern Taiwan: Impact of age, sex, education, and urbanization.] Neurol Sci. 1998;160:67-75. 5. Liu HC, Lin KN, Teng EL, et al. Prevalence and subtypes of dementia in Taiwan: A community survey of5297 individuals.] Am GeriatrSoc. 1995;43:144-149. 6. Liu HC, Chou P, Lin KN, et al. Assessing cognitive abilities and dementia in a predominantly illiterate population of older individuals in Kinmen. Psychol Med. 1994;24:763-770. 7. AmatniekJC, Frey LC, Hauser WA. Gender differences in diseases of nervous system. In: Kaplan PW, ed. Neurologic Disease in Women. New York, NY: Demos Medical Pub; 2006:433--442. 8. Liu CK, Lin RT, Chen YF, et al. Prevalence of dementia in an urban area in Taiwan.] Formos Med Assoc. 1996;95:762-768. 9. Wimo A, Jonsson L, Winblad B. An estimate of the worldwide prevalence and direct costs of dementia in 2003. Dement Geriatr Cogn Disord. 2006;21:175-181. 10. Wimo A, Winblad B, Jonsson 1. An estimate of the total worldwide societal costs of dementia in 2005. Alzheimers Dement. 2003;7:81-91. 11. Dunkin JJ, Anderson-Hanley C. Dementia caregiver burden: A review of the literature and guidelines for assessment and intervention. Neurology. 1998;51(Suppll):S53-S60, discussion S65-S67.
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12. Chiu L, Tang KY, Liu YH, et al. Cost comparisons between family-based care and nursing home care for dementia.] Adv Nurs. 1999;29:1005-1012. 13. Mueller E. The impact of demographic factors on economic development in Taiwan. Popul Dev Rev. 1977 ;3: 1-22. 14. Jonsson L, Eriksdotter Jonhagen M, Kilander L, et al. Determinants of costs of care for patients with Alzheimer's disease. Int] Geriatr Psychiatry. 2006;21 :449--459. 15. Leon J, Neumann PJ. The cost of Alzheimer's disease in managed care: A cross-sectional study. Am] Manag Care. 1999;5:867-877. 16. Chiu L, Tang KY, Liu YH, et al. Willingness of families caring for victims of dementia to pay for nursing home care: Results of a pilot study in Taiwan.] Manag Med. 1998;12:321,349-360. 17. World Health International Classification of Diseases, Ninth Revision, Clinical Modification, 2003 [CDC Web site}. fi:p://ftp.cdc.gov/pub/Health_Statistics/NCHS/Publications/ICD9-CM/ 2003/. Accessed September 9, 2008. 18. National Health Insurance Research Database. http://www.nhri.org.tw/nhird/datc04.htm. Accessed September 9, 2008. 19. Liu CK, Lai CL, Tai CT, et al. Incidence and subtypes of dementia in southern Taiwan: Impact of socio-demographic factors. Neurology. 1998;50:1572-1579. 20. Andersen K, Launer LJ, Dewey ME, et aI, for the EURODEM Incidence Research Group. Gender differences in the incidence of AD and vascular dementia: The EURODEM Studies. Neurology. 1999;53: 1992-1997. 21. Meek PD, McKeithan K, Schumock GT. Economic considerations in Alzheimer's disease. Pharmacotherapy. 1998;18:68-73; discussion 79-82. 22. Zhu CW, Scarmeas N, Torgan R, et al. Clinical features associated with costs in early AD: Baseline data from the Predictors Study. Neurology. 2006;66: 1021-1 028. 23. Allegri RF, Butman J, Arizaga RL, et al. Economic impact of dementia in developing countries: An evaluation of costs of Alzheimer-type dementia in Argentina. Int Psychogeriatr. 2007; 19:705-718. 24. Wang G, Cheng Q, Zhang S, et al. Economic impact of dementia in developing countries: An evaluation of Alzheimer-type dementia in Shanghai, China.] Alzheimers Dis. 2008;15:109-115. 25. Iezzoni LI. Assessing quality using administrative data. Ann Intern Med. 1997;127:666-674. 26. Menzin J, Lang K, Friedman M, et al. The economic cost of Alzheimer's disease and related dementias to the California Medicaid program CMedi-Cal") in 1995. Am] Geriatr Psychiatry. 1999;7: 300-308.
ADDRESS CORRESPONDENCE TO: Shun-Jin Lin, PhD, 100 Shi-Chuan 1st Rd, Kaohsiung, Taiwan. E-mail: [email protected]
18
Direct Medical Costs in Patients With Alzheimer's Disease in Taiwan: A Population-Based Study Agnes i.E Chan, MAMM1,2; Thau-Ming Cham, PhD 1; and Shun-Jin Lin, PhDl
lSchool o/Pharmacy, Kaohsiung Medical University, Kaohsiung, Taiwan; and 2 Chi Mei Medical Center, Tainan, Taiwan
ABSTRACT BACKGROUND: Alzheimer's disease (AD) has the potential to become a major health concern and associated health care costs may become a significant economic burden on society. OBJECTIVE: The aim of this study was to estimate the direct medical costs attributable to AD in patients aged ::0-60 years in Taiwan from 2000 through 2002 and to explore the correlation of these costs with patients' age and sex. METHODS: This study was based on the National Health Insurance Research Database of Taiwan's National Health Insurance (NHI) program. The NHI program insures >98% of the 23 million inhabitants of Taiwan. Detailed data were extracted from a random sample of 0.2% of inpatient and 5% of outpatient recipients with AD (International Classification 0/ Diseases, Ninth Revision, Clinical Modification diagnosis code 331.0) who were aged ::0-60 years and who received inpatient or outpatient services with claims from January 1,2000, to December 31, 2002. Duplicate charges for a specific patient and diagnoses of other types of dementia were excluded from this study. RESULTS: A total of 69,780 patients were found to have a diagnosis of AD. The direct medical costs for outpatients were estimated at US $1.2 million in 2000, US $1.9 million in 2001, and US $2.3 million in 2002; the costs for inpatient care were estimated at US $670,000 in 2000, US $2.4 million in 2001, and US $3.2 million in 2002. The total direct medical costs were estimated at US $1.86 million in 2000, US $4.24 million in 2001, and US $5.48 million in 2002. The increase of total direct medical costs was not significantly correlated with patients' age or sex. CONCLUSIONS: From 2000 through 2002, the direct medical costs of AD increased annually in Taiwan among patients with AD aged ::0-60 years. No significant correlation was found between increased total direct medical costs and sex or age. The cost estimate presented here has implications for future decision making about reallocating medical resources for treating AD in Taiwan. (Curr Ther Res Clin Exp. 2009; 70:10-18) © 2009 Excerpta Medica Inc. KEY WORDS: Alzheimer's disease, direct medical costs, Taiwan. Accepted for publication October 24, 2008. © 2009 Excerpta Medica Inc. All rights reserved.
10
doi: 10.1 0 16/j .curtheres.2009 .02 .005 001l-393X/$ - see front matter
A.L.F. CHAN ET AL.
INTRODUCTION
The prevalence of Alzheimer's disease (AD) in persons aged ::0-65 years has been estimated to be 2% to 10% in the United States and 3.3% to 6.0% in Europe. 1 In east Asia, the prevalence of AD has been estimated to be ~4.8% in China,2 2.1% in Japan,3 and 2% to 4% in Taiwan. 4- 7 The number of people with AD in these countries is increasing gradually as the population ages. s AD has the potential to become a major health concern and associated health care costs may become a significant burden worldwide. The estimate of the worldwide direct costs of AD and dementia care was increased from US $156 billion in 2003 9 to US $315 billion in 2005 10 annually and is projected to nearly double by 2025 to 600 billion.7,10 Care of individuals with AD and dementia consists of formal and informal care. The patterns of care differ throughout the world because of differences in cultures, families, care organizations, and financing. Some researchers assumed that 73% of people with dementia in developed countries lived at home and received 1.6 hours per day of informal care to assist with the personal activities of daily life. 10 However, determining the cost of informal care is a controversial and complicated issue. 1o In Taiwan, as in many other countries, families are the main caregivers to older AD patients who are no longer able to care for themselves. l l Such individuals usually require constant supportive care at home or in a nursing home (informal care) to improve their basic and instrumental activities of daily living and medical treatment (formal care).12 The costs of formal and informal care in patients with AD are high and are related to disease severity and the presence of behavioral disturbances. 13 - 15 A pilot study in Taiwan concluded that families with higher accessibility to nursing homes were willing to pay US $174 per month more than caregivers with lower accessibility.16 Family caregivers who are aged> 65 years, have more than a high school education, have a higher family income, and have easy accessibility to nursing home services were likely to attach higher economic value to nursing home placement. The economic and social burden of AD may become a major health care problem in Taiwan. However, to date, research analyzing the costs of AD in Taiwan has not been published. This is the first pilot study to assess the direct medical costs of AD in Taiwan to provide the National Health Insurance (NHI) program with economic data needed to make decisions about reallocating medical resources and establishing preventive care for the aging population. METHODS DATA SOURCE
Institutional review board approval was not required for this study because all personal data were kept confidential by the NHI. This study used a top-down approach based on the National Health Insurance Research Database (NHIRD) of Taiwan's NHI program. Data were extracted from a random sample of 0.2% inpatient and 5% outpatient insurance recipients with a diagnosis of AD (International Classification of Diseases, Ninth Revision, Clinical Modification [ICD-9-CM} diagnosis code 331.0).17 The sampling percentages were determined
11
CURRENT THERAPEUTIC RESEARCH
by the NHI, which also performed the randomization. The data files contain an original system for sampling claims data, including monthly claim summaries for inpatient claims, ambulatory care claims, inpatient expenditures by admissions, details of inpatient orders, ambulatory care expenditures by visits, details of ambulatory care orders, the primary diagnosis, up to 2 secondary diagnoses (in ICD-9-CM format), and a registry for beneficiaries. The registration file includes a registry for medical services and a registry for drug prescriptions. 1s The NHI program is a comprehensive program that insures >98% of the 23 million inhabitants of Taiwan. The NHIRD data are based on date of payment rather than date of service. The 2000 to 2001 paid claims files were used to create a 1-year file of claims for services provided during 2000; a similar procedure was used for 2001 and 2002 data. Payment for services provided is usually made within 3 months. Therefore, using 1 year of paid claims to create a 1-year file of services would have captured almost all relevant claims. Recipients who had invalid registry data were excluded from this study. The components of direct medical costs include costs of medications and laboratory tests, physicians' fees, pharmacist dispensing fees, room charges, meal service charges, diagnosis examination charges (eg, computed tomography, magnetic resonance imaging, single-photon emission computed tomography, positron emission tomography), supportive treatment charges (eg, psychotherapy), and rehabilitation charges. Total costs were indicated in US dollars using an exchange rate of Taiwan $I = US $32.80. ALZHEIMER'S DISEASE COHORT SELECTION
All NHI recipients who were eligible for ::0-1 day during 2000 and who had only 1 medical claim (NHI does not allow duplicate claims) within 90 days in that year with a primary or secondary diagnosis of AD were included. Diagnoses of other types of dementia (ICD-9-CM codes 290.0, 290.1, 290.10-290.13, 290.2, 290.20, 290.21, 290.3, 290.4, 290.40-290.43, 290.9, 294.9, 332.2, 331.89, 331.9, and 797) and possible duplicate charges for a specific patient within 90 days were also excluded from this study. STUDY MEASURES
Our study was focused on the direct medical costs to the NHI program from 2000 to 2002 for patient care. The direct medical costs for patients with the primary or secondary diagnosis of AD were calculated. STATISTICAL ANALYSIS
Descriptive analyses were conducted for the study cohort of patients with AD, including demographic characteristics, NHI care eligibility status, and months ofNHI care eligibility during 2000. The analyses were intended to describe the characteristics of the AD cohort and to identifY whether age and sex might influence direct medical costs. The differences between total direct medical costs with patients' age and sex were evaluated using the X2 test. The correlation between the increase in total direct medical costs and patients' age and sex were analyzed using Pearson correlation analysis.
12
A.L.F. CHAN ET AL.
RESULTS
A total of 69,780 patients who were aged ::0-60 years with an ICD-9-CM code of 331.0 noted as the primary or secondary diagnosis from 2000 to 2002 in the inpatient and outpatient claims file samples remained after we removed invalid claims, duplicate claims within 3 months in the same year, and persons with an invalid date of birth. Table I shows that 14.57% of patients were aged ::0-80 years, 1.36% were aged 60 to 69 years, 4.38% were aged 70 to 79 years, and 0.0008% were aged <;59 years. There were more female patients than male patients in both the outpatient and inpatient services (data not shown). The direct medical costs for outpatients were estimated at US $1.2 million in 2000, US $1.9 million in 2001, and US $2.3 million in 2002; the costs for inpatient care were estimated at US $670,000 in 2000, US $2.4 million in 2001, and US $3.2 million in 2002. The total direct medical costs for patients with a diagnosis of AD were estimated to be US $1.86 million in 2000, US $4.24 million in 2001, and US $5.48 million in 2002, which were ~0.02%, 0.05%, and 0.05% of the total health care expenditures in Taiwan, respectively (Table II). Expenditures for inpatient and outpatient services increased annually from 2000 to 2002. Mean annual cost per patient was US $1418 in 2000, US $3793 in 2001, and US $5005 in 2002. The increase in inpatient cost in 2000 was ~3.5-fold of that reported in 2001 (Tables III and IV). The cost of medications accounted for 39.4%, 34.4%, and 33.7% of the total direct medical costs claimed in 2000, 2001, and 2002, respectively (Table II). Based on our estimate of total direct medical costs, annual spending by the NHI program for AD is projected to be approximately US $105 million. The correlation between the increases in total direct medical costs and age was not significant; no linear relationship was found. Similarly, the correlation between total direct medical costs and sex was not significant. DISCUSSION
In this pilot study, we estimated the direct medical costs of AD and its correlation with patient sex and the increasing age of the population in Taiwan. Results suggest that the number of women aged> 75 years with AD was higher than that of men at the same age. This result is consistent with some local and Western studies that found that the prevalence of AD was higher in women than men, but the increase in incidence remains a controversial issue. 4 ,7,19,20 The age-adjusted incidence has been found to be higher in women, particularly with advancing age. The total direct medical costs for inpatient and outpatient care increased each year, with the increase being higher for inpatient than outpatient costs. The reason for this discrepancy might be that, in the early stages of AD, patients in Taiwan are generally unaware of their condition and remain at home until the disease becomes more severe and medical treatment is then sought. These results are consistent with the findings of Meek et al 21 that US patients are typically hospitalized in the later stages of AD, resulting in a greater proportion of direct costs for inpatient care. We found that the total direct medical costs and mean annual cost per patient increased from 2000 to 2002. This may be related to physicians using the ICD-9-CM
13
n c
:a :a
/II
z -I
t
Table I. Characteristics of patients in Taiwan with Alzheimer's disease.
/II
:a
:0;59 Years
l>
60-69 Years
"C -I n /II
Male
Female
Male
Female
SG
B*
SG
B*
SG
B*
SG
B*
500 520 0 1020 0.0007
9,349,760 9,419,945 9,497,868 28,267,573
0 20 0 20 0.0001
9,398,296 9,506,836 9,582,575 28,487,707
1020 2020 2520 5560 0.53
693,502 694,596 696,655 2,084,753
3040 3560 1020 7620 0.83
713,519 732,106 745,486 2,191,111
Year
:ll /II
'l>"
/II
2000 2001 2002 Total % of B
70-79 Years Male Year 2000 2001 2002 Total % of B
~80
Female
Years
Male
Female
Total
SG
B*
SG
B*
SG
B*
SG
B*
SG
B*
2620 3640 6180 12,440 1.54
528,131 539,650 545,541 1,613,322
5140 6080 7600 18,820 2.84
424,644 442,545 458,107 1,325,296
1620 5200 5220 12,040 5.28
138,687 151,643 165,147 455,477
2560 2600 7100 12,260 4.91
154,287 166,234 178,099 498,620
16,500 23,640 29,640 60,780 0.15
21,400,826 21,653,555 43,054,381 86,108,762
SG = study group; B = beneficiaries. *Bureau of National Health Insurance, Taiwan.
:a n
:t
Table II. Changes in direct medical costs (US $) associated with Alzheimer's disease in Taiwan claimed from 2000 through 2002.
Year
Total Health Expenditures Claimed (US $ Billion)
Outpatient
2000
9.0
1,190,584.60
672,474.50
1,863,059.10
0.02
734,193
39.4
2001
9.4
1,867,184.60
2,375,273.20
4,242,457.80
0.05
1,459,028
34.4
Direct Medical Costs Claimed Inpatient
Total
% of Total Health Care Expe nd itu res Claimed
Medication Expenses
Medication Portion of Medical Costs Claimed, %
2002
10.3
2,330,369.20
3,151,787.70
5,482,156.90
0.05
1,848,386
33.7
Total
28.7
5,388,138.50
6,199,535.40
11,587,673.00
0.04
4,041,607
34.9
~
r :'I
n
:t l> Z
.. til
/II
-I
l>
r
CURRENT THERAPEUTIC RESEARCH
Table III. Total direct medical costs (US $) associated with Alzheimer's disease for outpatient care in Taiwan. Year
No. of Patients
Total Direct Medical Cost
Mean (SO)
2000 2001 2002 Total
16,000 23,000 29,000 68,000
1,190,584.60 1,867,184.60 2,330,369.20 5,388,138.40
5445.90 (5325.90) 5984.00 (3976.80) 6384.70 (5933.60)
Table IV. Total direct medical costs (US $) associated with Alzheimer's disease for inpatient care in Taiwan. Year
No. of Patients
Total Direct Medical Cost
Mean (SO)
2000 2001 2002 Total
500 640 640 1780
672,474.50 2,375,273.20 3,151,787.70 6,199,535.40
104,514.20 (67,758.70) 333,571.50 (390,811.70) 534,967.60 (567,473.20)
code for AD more accurately or to annual economic inflation. Compared with other countries, the annual direct medical cost per patient reported in the United States was US $7929,22 US $3420 to US $9658 in Argentina,23 US $1766 in Turkey, 1 and US $1058 in China. 24 The costs found in our study were lower than those reported in the Western countries, but higher than the costs in China. Another variable, medication costs, is also associated with direct medical costs. More than 30% of the total direct medical costs for the treatment of AD were for drugs. This finding is lower than the finding in a previous study in which drug costs accounted for 36.0% of total direct medical costs in patients in the early stages of AD22 and an average of 66.0% in patients at all stages of the disease. 1 This may be due to a policy that restricts the global medication budget (the amount is determined by the individual hospital's global budget issued by the Bureau of National Health Insurance in Taiwan).18 The correlation between the increases in total direct medical cost with age and sex of the population was small and no linear relationship was found in our study. However, the effects of age and sex remain of concern in AD, as indicated by the findings of 2 studies conducted in southern Taiwan: one study found age to be a major risk factor for AD4 and the other found that being of female sex was probably an AD risk factor. 19 LIMITATIONS
This study was subject to several limitations that are inherent in investigations that rely on the use of health insurance claims data. 25,26 Patients may have been coded with a diagnosis of AD while in fact they had another form of dementia. Similarly, some patients may have been miscoded as having other forms of dementia that were excluded
16
A.L.F. CHAN ET AL.
from the study. In addition, patients in the early stages of AD, when it is difficult to diagnose, may not have had this diagnosis recorded on the claims files and thus would not have been included in this study. In this pilot study, we did not control for differences in other covariants (eg, major chronic comorbid conditions, other prevalent conditions). Therefore, disease prevalence and costs may have been underestimated. Another limitation of this study was the lack of NHIRD data for disease severity. Consequently, we were unable to estimate the effects of the severity of AD on costs. Therefore, the standard errors of these estimates were large and the coefficients were not statistically significant. The inability to separate AD costs from other costs in AD patients was also a limitation of the study. The increasing number of elderly people poses a challenge for health care providers and countries providing national health care insurance. Further research into the economic burden, including direct and indirect medical costs of AD in Taiwan, is therefore an important priority. CONCLUSIONS From 2000 through 2002, the direct medical costs of AD increased annually in Taiwan among patients with AD aged ::0-60 years. No significant correlation was found between increased total direct medical costs and sex or age. Results from this study should be considered in reallocating limited medical resources for treating AD in Taiwan. REFERENCES 1. Zencir M, Kuzu N, Be§er NG, et al. Cost of Alzheimer·s disease in a developing country setting. Int] Geriatr Psychiatry. 2005;20:616-622. 2. Zhang ZX, Zahner GE, Roman GC, et al. Dementia subtypes in China: Prevalence in Beijing, Xian, Shanghai, and Chengdu. Arch Neurol. 2005;62:447--453. 3. Yamada T, Hattori H, Miura A, et al. Prevalence of Alzheimer·s disease, vascular dementia and dementia with Lewy bodies in a Japanese population. Psychiatry Clin Neurosci. 2001;55:21-25. 4. Lin RT, Lai CL, Tai CT, et al. Prevalence and subtypes of dementia in southern Taiwan: Impact of age, sex, education, and urbanization.] Neurol Sci. 1998;160:67-75. 5. Liu HC, Lin KN, Teng EL, et al. Prevalence and subtypes of dementia in Taiwan: A community survey of5297 individuals.] Am GeriatrSoc. 1995;43:144-149. 6. Liu HC, Chou P, Lin KN, et al. Assessing cognitive abilities and dementia in a predominantly illiterate population of older individuals in Kinmen. Psychol Med. 1994;24:763-770. 7. AmatniekJC, Frey LC, Hauser WA. Gender differences in diseases of nervous system. In: Kaplan PW, ed. Neurologic Disease in Women. New York, NY: Demos Medical Pub; 2006:433--442. 8. Liu CK, Lin RT, Chen YF, et al. Prevalence of dementia in an urban area in Taiwan.] Formos Med Assoc. 1996;95:762-768. 9. Wimo A, Jonsson L, Winblad B. An estimate of the worldwide prevalence and direct costs of dementia in 2003. Dement Geriatr Cogn Disord. 2006;21:175-181. 10. Wimo A, Winblad B, Jonsson 1. An estimate of the total worldwide societal costs of dementia in 2005. Alzheimers Dement. 2003;7:81-91. 11. Dunkin JJ, Anderson-Hanley C. Dementia caregiver burden: A review of the literature and guidelines for assessment and intervention. Neurology. 1998;51(Suppll):S53-S60, discussion S65-S67.
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12. Chiu L, Tang KY, Liu YH, et al. Cost comparisons between family-based care and nursing home care for dementia.] Adv Nurs. 1999;29:1005-1012. 13. Mueller E. The impact of demographic factors on economic development in Taiwan. Popul Dev Rev. 1977 ;3: 1-22. 14. Jonsson L, Eriksdotter Jonhagen M, Kilander L, et al. Determinants of costs of care for patients with Alzheimer's disease. Int] Geriatr Psychiatry. 2006;21 :449--459. 15. Leon J, Neumann PJ. The cost of Alzheimer's disease in managed care: A cross-sectional study. Am] Manag Care. 1999;5:867-877. 16. Chiu L, Tang KY, Liu YH, et al. Willingness of families caring for victims of dementia to pay for nursing home care: Results of a pilot study in Taiwan.] Manag Med. 1998;12:321,349-360. 17. World Health International Classification of Diseases, Ninth Revision, Clinical Modification, 2003 [CDC Web site}. fi:p://ftp.cdc.gov/pub/Health_Statistics/NCHS/Publications/ICD9-CM/ 2003/. Accessed September 9, 2008. 18. National Health Insurance Research Database. http://www.nhri.org.tw/nhird/datc04.htm. Accessed September 9, 2008. 19. Liu CK, Lai CL, Tai CT, et al. Incidence and subtypes of dementia in southern Taiwan: Impact of socio-demographic factors. Neurology. 1998;50:1572-1579. 20. Andersen K, Launer LJ, Dewey ME, et aI, for the EURODEM Incidence Research Group. Gender differences in the incidence of AD and vascular dementia: The EURODEM Studies. Neurology. 1999;53: 1992-1997. 21. Meek PD, McKeithan K, Schumock GT. Economic considerations in Alzheimer's disease. Pharmacotherapy. 1998;18:68-73; discussion 79-82. 22. Zhu CW, Scarmeas N, Torgan R, et al. Clinical features associated with costs in early AD: Baseline data from the Predictors Study. Neurology. 2006;66: 1021-1 028. 23. Allegri RF, Butman J, Arizaga RL, et al. Economic impact of dementia in developing countries: An evaluation of costs of Alzheimer-type dementia in Argentina. Int Psychogeriatr. 2007; 19:705-718. 24. Wang G, Cheng Q, Zhang S, et al. Economic impact of dementia in developing countries: An evaluation of Alzheimer-type dementia in Shanghai, China.] Alzheimers Dis. 2008;15:109-115. 25. Iezzoni LI. Assessing quality using administrative data. Ann Intern Med. 1997;127:666-674. 26. Menzin J, Lang K, Friedman M, et al. The economic cost of Alzheimer's disease and related dementias to the California Medicaid program CMedi-Cal") in 1995. Am] Geriatr Psychiatry. 1999;7: 300-308.
ADDRESS CORRESPONDENCE TO: Shun-Jin Lin, PhD, 100 Shi-Chuan 1st Rd, Kaohsiung, Taiwan. E-mail: [email protected]
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