Resource Utilization and Costs of Age-Related Michael T. Halpern, M.D., Ph.D., Jordana K. Schmier, M.A., David Covert, M.B.A., and Krithika Venkataraman, Ph.D.

Data were analyzed from the 1999-2001 cause vision loss, although change in dru- Medicare Beneficiary Encrypted Files for sen size or number is associated with patients with age-related macular degen- increased risk for development of AMD. eration (AMD), an ophthalmic condi- There are two basic forms of AMD: atro- tion characterized by central vision loss. phic (dry) and exudative (wet). Dry AMD, Classifying AMD subtype by International the more common form of the disease, Classification of Diseases, Ninth Revision, occurs in approximately 85 to 90 percent of Clinical Modifications (ICD-9-CM) (Centers patients with AMD and is generally slow to for Disease Control and Prevention, 2003) progress. An advanced form of dry AMD, code, resource utilization rates increased , occurs in about 5 per- with disease progression. Individuals with cent of patients and may be characterized more severe disease (wet only or wet and by a gradual loss of visual function. Wet dry AMD) had greater costs than did those AMD, which is characterized by choroidal with less severe disease (drusen only or dry neovascularization (CNV), is usually more only). Costs among patients with wet disease severe and is responsible for 90 percent of increased yearly at rates exceeding infla- vision loss attributed to AMD. It occurs in tion, possibly due in part to increased rates only about 10 percent of patients with AMD of treatment with photodynamic therapy (Macular Degeneration Partnership, 2005). among these individuals and the aging of the A recent report from the Age-Related population. Disease Study (AREDS) indicated that approximately 8 million persons in the U.S. INTRODUCTION age 55 or over have some form of interme- diate or advanced AMD (Clemons et al., AMD is an ophthalmic condition charac- 2003). terized by acquired lesions of the macula Wet AMD is commonly associated region. These pathologic changes usually with clinically significant loss of vision, appear in individuals age 50 or over and regardless of either the original location result in alteration of central visual func- or characteristics of the CNV. Treatment tion. Lesions are associated with abnor- options for AMD are limited. Currently, malities of the retinal pigment epithelium three approved treatment options exist and/or the sensory (cone and rod for patients with exudative AMD: (1) photoreceptors), and may be related to the photocoagulation, (2) ophthalmic photo- appearance of drusen (hyaline deposits dynamic therapy (PDT) with verteporfin, beneath the retinal pigment epithelium). and (3) pegaptanib sodium injection. Many The appearance of drusen alone does not AMD patients do not meet the criteria for Michael T. Halpern and Jordana K. Schmier are with Exponent Inc. treatment, i.e., they have early or inter- David Covert is with Alcon Research Ltd. Krithika Venkataraman is with AstraZeneca, LP. The statements expressed in this article mediate AMD without CNV (American are those of the authors and do not necessarily reflect the views Academy of , 2005). For or policies of Exponent Inc., Alcon Research Ltd., or the Centers for Medicare & Medicaid Services (CMS). those who do meet the criteria and are

Health Care Financing Review/Spring 2006/Volume 27, Number 3 37 treated, patients may still experience high METHODS rates of recurrence in treated vessels, the need for repeat procedures, and/or Data were analyzed from the 1999, 2000, clinically significant vision loss (Fine et and 2001 Medicare Beneficiary Encrypted al., 2000; O’Neill et al., 2001). In addition Files (BEF). The BEF represents a random to these currently used therapies, other 5-percent sample of all Medicare enrollees therapies are being investigated. and is representative of all U.S. citizens In addition to increasing morbidity and age 65 or over. The random sample used decreasing patient quality of life, AMD is for this claims data set is selected based on likely associated with substantial medi- the same algorithm each year. Thus, the cal care costs. However, much of the lit- same patients are included in the BEF data erature on the costs of visual impairment each year (unless they die) as well as new has focused on glaucoma, cataracts, and patients entering each year; therefore, longi- . These conditions are tudinal treatment patterns can be evaluated. more prevalent than AMD in the U.S. The BEF data consist of seven claims com- population age 50 or over. Prevalence of ponents: (1) Inpatient; (2) Outpatient; (3) glaucoma is 8 percent among individu- Durable Medical Equipment; (4) Hospice; als with diabetes and 4 percent in people (5) Home Health Agency; (6) Skilled without diabetes; prevalence of cataracts Nursing Facility (nursing home); and (7) is 34 versus 20 percent in individuals with Physician/Supplier (Part B) claims. and without diabetes, respectively; and For this study, data from the Outpatient prevalence of diabetic retinopathy is 10 and Part B (Physician/Supplier) files from percent (Centers for Disease Control and all patients with two or more claims for Prevention, 2004). In contrast, the preva- AMD (ICD-9-CM 362.5) were included. lence of AMD is approximately 3 percent Two separate claims with an AMD diagno- in older Americans, regardless of diabetes sis code were required as patients with a status (Centers for Disease Control and single claim for this diagnosis may be relat- Prevention, 2004). In a review of cost of ill- ed to a rule-out visit for AMD. Furthermore, ness issues in AMD, O’Neill and colleagues patients were included in the analysis only (2001) reported that few data are available if they had one or more claims with ICD-9- on the direct costs of AMD. Given the age CM diagnosis codes for specific subtypes distribution of AMD, most patients in the of AMD, namely dry (ICD-9-CM 362.51), U.S. receive coverage of medical services wet (362.52), or drusen (362.57). Based on from Medicare; thus, Medicare data could these diagnosis codes, patients were clas- be considered the most appropriate source sified as having dry AMD, wet AMD, both of information on resource utilization and dry and wet AMD, or drusen only. Patients costs of AMD. The objective of this study were classified in the drusen only group if was to evaluate resource utilization, treat- they did not have claims specific for either ment patterns, and medical care costs for wet or dry AMD. This group was included AMD patients using Medicare claims data in the analysis because of the increased and to compare results for patients with risk for development of AMD compared dry versus wet disease. to a general population. Any AMD patient may have also had a concomitant diagnosis

38 Financing Review/Spring 2006/Volume 27, Number 3 of drusen; however, patients with a con- specialist consultations (0.15) compared comitant drusen diagnosis comprised less to the other specified subgroups. Patients than 8 percent of each group. with dry only had similar rates of resource Resource utilization for AMD patients utilization to drusen only patients. was determined from Outpatient and Part B In 1999, both wet only and wet and claims. Costs were derived from Medicare dry AMD patients had similar rates of payments. All data analysis was performed resource utilization for certain diagnostic using SAS® Version 8.1 (SAS Institute Inc., tests, including retinal ultrasound and visu- 2002). al field examinations. However, wet only patients had lower rates than wet and dry RESULTS patients for visual refraction (0.25 versus 0.37) and indocyanine-green Table 1 presents demographic charac- (0.065 versus 0.091). Similarly, wet only teristics of the Medicare BEF patients by AMD patients had lower average annual AMD subtype and study year (1999, 2000, numbers of (0.82) and of or 2001). With the exception of drusen- photographs (0.91) compared to val- only patients, the proportion of patients ues for wet and dry patients (1.39 and 1.43, with AMD generally increased with age. respectively). With respect to therapeutic The greatest proportion of patients in the procedures, both groups had similar rates drusen only category (the earliest stage of of photocoagulation (0.10 versus 0.11) and AMD) occurred in the 75 to 79 age group. similar annual number of PDT procedures Approximately two-thirds of patients were (0.12 versus 0.16). Wet and dry patients female and the overwhelming majority had higher annual numbers of ophthal- (>90 percent) was white. mologist visits (1.97), generalist physician Table 2 presents resource utilization visits (2.28), and specialist consultations data from 1999 for the included AMD (0.64) compared to all other groups. patients. Resource utilization is presented Striking differences were seen among for all four AMD subtypes. Further, for wet only and wet and dry patients who patients classified as wet only or wet and received one or more PDT procedures dry who received PDT, resource utilization during the year versus those that did not is presented separately. In most instanc- receive any PDT. Patients receiving at least es, drusen only patients had the highest one PDT procedure were also more likely rates of resource utilization for diagnos- to undergo photocoagulation, tic services. These diagnostic services angiography, indocyanine-green angiogra- per patient included retinal ultrasound phy, ophthalmoscopy, and fundus photog- (0.069) for drusen only, visual refraction raphy. In contrast, patients who did not (0.56), and visual field examinations (0.13). receive any PDT procedures were more However, drusen only patients had lower likely to receive retinal ultrasound or visual rates of indocyanine-green angiography field examination. (0.0024), a procedure used in detecting Annual costs reflect these differences occult neovascularizations, compared to in resource utilization. Costs for drusen wet only (0.065) or wet and dry (0.091) only and dry only AMD patients for 1999 AMD patients. Drusen only patients also are similar ($204 to $206). Wet only AMD had lower rates of ophthalmologist visits patients had annual costs two and one-half (1.4), generalist physician visits (0.80), and times those of dry only AMD patients

Health Care Financing Review/Spring 2006/Volume 27, Number 3 39 Table 1 Demographic Characteristics of Medicare Beneficiary Encrypted File Patients, by Age-Related Macular Degeneration Subtype and Year: 1999-2001 Demographic All Patients Drusen Only Dry Only1 Wet Only2 Dry and Wet3 1999 N=58,594 N=7,788 N=38,376 N=7,441 N=4,989 Age Percent <65 Years 1.1 2.2 1.0 1.2 0.5 65-69 Years 7.6 13.0 7.0 6.5 5.1 70-74 Years 16.3 23.4 15.4 15.2 13.3 75-79 Years 23.8 26.4 23.3 22.7 25.5 80-84 Years 24.2 20.0 24.4 26.0 26.5 >84 Years 27.0 15.0 28.9 28.6 29.0 Sex Male 32.7 31.8 32.5 34.2 33.0 Female 67.4 68.2 67.5 65.8 67.0 Race White 94.7 92.4 94.9 94.7 96.9 Black 2.3 3.8 2.2 2.0 0.8 Other 3.0 3.8 2.9 3.3 2.3

2000 N=61,977 N=7,788 N=40,301 N=8,070 N=5,793 Age <65 Years 1.0 1.8 1.0 1.1 0.4 65-69 Years 7.1 12.4 6.6 6.2 4.7 70-74 Years 15.8 22.4 15.1 14.6 13.3 75-79 Years 23.6 26.2 23.3 23.2 23.0 80-84 Years 24.5 21.5 24.5 25.7 27.0 >84 Years 28.0 15.7 29.6 29.3 31.6 Sex Male 32.5 31.6 32.2 34.3 33.6 Female 66.5 68.4 67.8 65.7 66.4 Race White 94.8 92.4 94.8 95.3 97.0 Black 2.1 3.6 2.1 1.6 0.7 Other 3.1 4.0 3.1 3.1 1.8

2001 N=60,896 N=6,942 N=39,162 N=8,290 N=6,502 Age <65 Years 1.0 2.1 0.9 1.0 0.5 65-69 Years 6.2 10.7 5.7 5.9 4.8 70-74 Years 15.0 21.8 14.5 12.8 12.9 75-79 Years 23.0 25.4 22.6 22.7 23.4 80-84 Years 25.4 22.6 25.3 26.4 28.2 >84 Years 29.4 17.5 31.0 31.2 30.3 Sex Male 32.5 30.9 32.2 35.0 32.9 Female 67.5 69.1 67.8 65.0 67.1 Race White 95.6 93.1 95.5 96.0 97.9 Black 2.1 3.8 2.2 1.5 0.9 Other 2.3 3.1 2.3 2.5 1.2 1 The proportion of dry only patients who also have a diagnosis of drusen is 4.1 percent in 1999, 4.5 percent in 2000, and 4.9 percent in 2001. 2 The proportion of wet only patients who also have a diagnosis of drusen is 4.6 percent in 1999, 5.2 percent in 2000, and 5.5 percent in 2001. 3 The proportion of wet and dry patients who also have a diagnosis of drusen is 7.2 percent in 1999, 7.5 percent in 2000, and 8.2 percent in 2001. SOURCE: Halpern, M.T., Schmier, J.K., Exponent Inc., Covert, D., Alcon Research Ltd. and Venkataraman, K., AstraZeneca, LP, 2006.

($513), while wet and dry patients had most diagnostic tests compared those with annual costs almost four times those of dry wet only or wet and dry AMD. Conversely, only AMD patients($767). drusen only and dry only AMD patients Resource utilization patterns for 2000 had lower rates of indocyanine-green angi- (Table 3) and 2001 (Table 4) are similar ography and photocoagulation procedures, to those from 1999. Patients with drusen fewer generalist physician visits, and fewer only and dry only AMD had similar rates of specialist consultations compared to the resource utilization, and had higher rates of other specified subgroups. Comparing wet

40 Health Care Financing Review/Spring 2006/Volume 27, Number 3 Dry, 4.79 4.02 2.26 0.082 0.33 0.15 1.84 0.97 2.19 2.65 =423 and N Wet $2,430.30 Dry, Dry

PDT PDT 1.41 1.19 0.067 0.35 1.31 0.066 0.12 0.38 0.023 0.11 0 0.61 1.95 2.25 and and =4,566 No N Wet Wet

$612.95

=4,989 N

$767.03 2006. Only,

1.85 0.16 =486 LP, N Wet

$2,233.74 AstraZeneca, Only,

Only PDT PDT All 0.84 0.73 4.51 3.6 1.7 1.43 0.77 0.11 0.25 1.5 0.097 0.054 0 0.24 1.39 0.12 0.2 0.37 0.33 0.11 0.81 0.64 1.37 1.28 1.53 1.99 1.97 2.28 K., =6,955 N Wet Wet

Table 2 Table $392.25 Venkataraman,

1.08 0.91 0.82 0.1 0.25 0.12 0.36 1.38 1.32 and =7,441

N Ltd.

$512.52 Research

Only All No

0.2 0.24 0.0016 0.065 0.049 0.29 0.091 0.41 0.069 0.1 0.46 0.051 0.0084 0 0.053 0.1 0.17 0.023 0.062 1.31 0.89 =38,376 N Alcon

D., Covert, $204.43 Only Dry

Inc.,

0.14 0.21 0.54 0.069 0.13 0.56 0.012 0 0.15 0.8 1.4

=7,788 N $205.93 Drusen Exponent patient. 0.0024 per J.K.,

1

1 1 (PDT) Schmier, utilization

2 Angiography Medicare Age-Related Macular Degeneration (AMD) Resource Utilization and by AMD Costs, 1999 Subtype: M.T., Visits patient. Therapy resource Exam Angiography per of Visits Halpern,

Photography rate cost Ultrasound Field Refraction Subtype Reimbursement Annual Annual AMD SOURCE: Fluorescein Fundus Indocyanine-Green

Diagnostic Procedures Ophthalmoscopy Retinal Visual Visual Therapeutic Procedures Photocoagulation Photodynamic Physician Interactions Consultations Total 1 2 Ophthalmologist Generalist

Health Care Financing Review/Spring 2006/Volume 27, Number 3 41 Dry, 4.96 3.69 2.2 0.053 0.1 0.34 1.87 1.1 2.25 2.69 666 and Wet $2,744.22 Dry, Dry

PDT PDT 1.54 1.25 0.058 0.29 1.34 0.08 0.1 0.36 0.061 0 0.063 0.71 2.14 1.94 and and 5,127 No Wet Wet $773.43

$1,000.00 2006. Only,

1.8 0.22 LP, Wet $2,353.77 AstraZeneca, Only,

Only PDT PDT All 0.93 0.75 4.19 2.87 1.94 1.53 0.78 0.26 1.6 0 0.19 1.43 0.36 0.39 0.8 0.75 1.44 1.17 1.71 1.8 2.16 2.03 K., Wet Wet Table 3 Table $485.09 Venkataraman,

1.25 0.96 0.86 0.078 0.25 0.08 0.17 0.05 0.43 0.1 1.46 1.23 and

Ltd. $665.01 Research

Only All No

0.22 0.25 0.0007 0.063 0.036 0.31 0.085 0.42 0.073 0.11 0.47 0.049 0.0087 0 0.052 0.063 0.2 0.02 0.063 0.077 0.067 0.061 1.4 0.81 40,301 8,070 7,293 777 5,793 Alcon

D., Covert, $258.83 Only Dry

Inc.,

0.15 0.24 0.55 0.013 0.17 0.085 0.13 0.58 0 0.74 1.48

7,813 $264.36 Drusen Exponent patient. 0.0013 per J.K.,

1

1 1 (PDT) Schmier, utilization

2 Angiography Medicare Age-Related Macular Degeneration (AMD) Resource Utilization and by AMD Costs, 2000 Subtype: M.T., Visits patient. Therapy resource

Exam Angiography per of Patients Visits Halpern,

of Photography rate cost Ultrasound Field Refraction Subtype Reimbursement Annual Annual AMD Number SOURCE: Fluorescein Fundus Indocyanine-Green

Diagnostic Procedures Ophthalmoscopy Therapeutic Procedures Photocoagulation Physician Interactions Consultations 1 2 Retinal Visual Visual Photodynamic Total Ophthalmologist Generalist

42 Health Care Financing Review/Spring 2006/Volume 27, Number 3 Dry, 5.06 3.73 2.5 0.095 0.33 2.45 1.15 3.23 2.53 and Wet $4,030.23 Dry, Dry

PDT PDT 1.54 1.22 0.072 0.23 1.56 0.074 0.13 0.4 0.041 0.042 0 0.046 0.73 2.68 1.87 and and 5,086 1,416 No Wet Wet $913.59

$1,592.33 2006. Only,

0.18 0.39 2.63 0.53 LP, Wet $3,549.69 AstraZeneca, Only,

Only PDT PDT All 0.89 0.74 4.31 2.95 2.31 1.76 0.94 0.3 1.55 0 1.76 0.38 0.74 0.82 1.86 1.16 2.39 1.74 2.8 2.01 K., Wet Wet Table 4 Table $567.35 Venkataraman,

1.61 1.2 1.07 0.076 0.28 0.084 0.55 0.045 0.46 0.12 1.97 1.28 and

Ltd. $1,190.44 Research

Only All No

0.25 0.32 0.0008 0.078 0.036 0.24 0.11 0.53 0.091 0.13 0.57 0.048 0.0097 0 0.051 0.051 0.24 0.035 0.057 0.067 0.03 0.043 1.79 0.86 39,162 8,290 6,558 1,732 6,502 Alcon

D., Covert, $346.89 Only Dry

Inc.,

0.15 0.27 0.67 0.096 0.16 0.73 0.01 0 0.17 0.74 1.95

6,942 $334.16 Drusen Exponent patient. 0 per J.K.,

1

1 1 (PDT) Schmier, utilization

2 Angiography Medicare Age-Related Macular Degeneration (AMD) Resource Utilization and by AMD Costs, 2001 Subtype: M.T., Visits patient. Therapy resource

Exam Angiography per of Patients Visits Halpern,

of Photography rate cost Ultrasound Field Refraction Subtype Reimbursement Annual Annual AMD Number SOURCE: Fluorescein Fundus Indocyanine-Green

Diagnostic Procedures Ophthalmoscopy Retinal Visual Visual Therapeutic Procedures Photocoagulation Photodynamic Physician Interactions Consultations Total 1 2 Ophthalmologist Generalist

Health Care Financing Review/Spring 2006/Volume 27, Number 3 43 only and wet and dry AMD patients in suggests that over this 3-year period, as 2000 and 2001, wet only patients had lower specialists performed more of the medical rates of most diagnostic procedures (visual care for AMD patients, use of specialized refraction, indocyanine-green angiography, techniques (both diagnostic and therapeu- ophthalmoscopy, and fundus photographs). tic procedures) became more common. Wet only AMD patients also had lower Costs for care of AMD increased each annual numbers of ophthalmologist visits, year for each subgroup. However, the generalist physician visits, and specialist increase in costs was greater than that consultations. Despite these lower levels of attributable to inflation using the medical resource utilization among wet only AMD care services component of the consumer patients, therapeutic procedures (photoco- price index (CPI). For example, average agulation and PDT) were similar between annual costs for patients with wet only wet only and wet and dry patients. Total AMD increased by approximately 30 per- costs reflect these differences in resource cent from 1999 to 2000 and by almost 79 utilization in a similar manner to that seen percent from 2000 to 2001. In contrast, the in Table 2. increase in the medical care services CPI The proportion of wet only patients was 4.3 percent from 1999 to 2000 and 4.8 receiving PDT increased over this 3-year percent from 2000 to 2001. This increase period, reflecting the increasing accep- reflects both greater numbers of patients tance of PDT into general practice. The receiving expensive services (e.g., PDT) proportion of wet only patients receiving and more frequent use of these services. one or more PDT treatments increased from 7.3 percent in 1999 to 10.4 percent in DISCUSSION 2000 and 21.2 percent in 2001. In contrast, rates of photocoagulation among wet only This study evaluated rates of resource AMD patients decreased from over 11 per- utilization and costs for individuals with cent of patients in 1999 to approximately AMD. In general, rates of resource uti- 6 percent in 2000 and 4 percent in 2001. lization increased with disease progres- Among patients who received any PDT sion. Patients with drusen or dry AMD treatments, the number of annual treat- generally experienced the lowest rates of ments remained fairly constant between resource utilization, while those with wet 1999 (1.84) and 2000 (1.87), but increased AMD or mixed wet and dry experienced substantially in 2001 (2.45). The rates of the greatest. For certain diagnostic proce- diagnostic procedures also increased over dures associated with defining AMD type this 3-year period. For example, among or monitoring AMD progression, resource drusen only and dry only AMD patients, utilization rates were higher among the retinal ultrasound increased from less than earlier stage patients. However, for all 7 percent in 1999 to over 9 percent in 2001; therapeutic procedures, rates were greater also increased in these among those with more advanced disease. groups. Rates of fluorescein angiography In all cases, individuals with wet or wet increased annually among wet only AMD and dry AMD had greater costs than did patients. Further, the annual number of drusen or dry AMD patients. ophthalmologist visits and specialist con- Results in this study are based on clas- sultations increased for each group each sification of patients using ICD-9-CM codes year, while the annual number of generalist for AMD subtypes. A large proportion physician visits tended to decrease. This of the total Medicare AMD population

44 Health Care Financing Review/Spring 2006/Volume 27, Number 3 did not have claims with diagnosis codes patients with diagnosed unilateral AMD), specifying subtype (i.e., they had claims drusen were found in 15 (88 percent) of with diagnosis codes only for unspecified the 17 undiagnosed fellow (Ishiko AMD). These individuals were therefore et al., 2002). This suggests a risk for not included in the analysis. If patients with development of binocular disease among Medicare claims for only unspecified AMD AMD patients with diagnosed monocular are substantially different from those with disease. Drusen have been reported to specified AMD subtypes, our results may represent a risk factor or preliminary stage have limited generalizability. However, of AMD (Wang et al., 2003). In the present our results are still generalizable to the study, a small proportion of patients (4 to 8 Medicare population with AMD subtype(s) percent) in the dry only, wet only, and wet specified. and dry categories also had diagnoses for In this study, we were able to present drusen. These patients may be a greater results only in terms of cost per patient, risk for progression to binocular AMD. not per eye. There are no ICD-9-CM diag- A number of previous studies have eval- nosis codes that separate binocular from uated ophthalmologic services covered by monocular AMD. Further, while physi- Medicare. In 1983, ophthalmology was sec- cians can report on the eye receiving treat- ond only to internal medicine in the total ment as part of the Medicare billing pro- volume of approved charges in Medicare cess (as a Healthcare Common Procedure (Frenkel, 1986). An analysis of the 1991 Coding System modifier code) (Centers Medicare 5-percent sample found that the for Medicare & Medicaid Services, 2005), mean number of visits per eye care ben- specifying the eye or eyes involved is not eficiary is 2.7, although the mode was required to receive payment. Thus, few of one visit (Ellwein et al., 1996). Males and the claims in the Medicare data included females had almost the same number of specification of left or right eye. Among visits per year (2.72 versus 2.73), and there the subgroup of patients who did have was an increase in visits by age group. In one or more claims specifying left versus addition, black beneficiaries received more right eye, approximately one-half of the visits (3.09 per year) than white beneficia- patients had binocular disease (i.e., they ries (2.71 per year). Macular degeneration had separate claims for the left and right was the primary diagnosis code listed for eyes) while the other one-half had claims 4.9 percent of ophthalmologist visits and associated with only one eye. This does not 4.8 percent of optometrist visits. Cataracts mean that one-half of the Medicare AMD and glaucoma were the only more common population had monocular disease; rather, diagnoses listed for visits to eye care pro- among one-half of the AMD patients, we fessionals than macular degeneration. are unable to determine whether they had In our study, rates of AMD-related monocular or binocular disease. resource utilization increased from 1999 Little information is available regarding to 2001. Ellwein and Urato (2002) also the incidence of monocular versus binocu- reported that the proportion of Medicare lar AMD and the risk of progression from beneficiaries receiving eye care through monocular to binocular disease. A number fee-for-service providers increased over of studies have indicated that approxi- an 8-year period. Over two-thirds of eye mately 50 percent of patients with AMD care visits and charges were for ophthal- have binocular disease (Vinding, 1990). mologist care, but the proportion of visits However, in a small study from Japan (17 with optometrists increased from 10.8 to

Health Care Financing Review/Spring 2006/Volume 27, Number 3 45 14.3 percent during the study period. The Costs of inpatient care may also be high- proportion of Medicare patients having er for patients with visual impairment, as one or more claims for macular degenera- was shown using New York State hospital tion increased each year from 1991-1998, discharge data (Morse et al., 1999). The from 3.52 to 4.53 percent. This may reflect average length of stay among patients with increasing incidence of AMD over time or visual impairment was 2.4 days longer than changes in the detection and diagnosis of that for patients without visual impairment. AMD. The increased length of stay for patients In a study of Medicare recipients, Javitt with visual impairment could be due to lack et al. (2003) reported the 3-year incidence of discharge planning, which may be more of wet AMD as being between 9.4 and 11.4 complicated for those with low vision. This per 1,000 Americans age 65 or over. The suggests that the visual impairment associ- results from their study may not be direct- ated with AMD can have substantial costs, ly comparable to our study, as these inves- in addition to treatment for AMD. tigators included patients with serous/ In summary, these results indicate sub- exudative detachment of retinal pigment stantial rates of resource utilization and epithelium (ICD-9-CM 362.42) and hemor- associated Medicare reimbursements for rhagic detachment of retinal pigment epi- individuals with AMD. Further research in thelium (362.43), while we excluded these the prevention, treatment, and outcomes patient groups. Further, they excluded associated with AMD is needed to quantify patients with dry AMD (ICD-9-CM 362.51) the burden of this condition to Medicare or drusen (362.57); we included these enrollees as well as to develop appropriate patients to assess differences in resource guidelines for its treatment. Results from utilization rates and costs associated with AREDS, evaluating the impacts of nutri- different types of AMD. They also used cri- tional supplements on AMD progression, teria separating ophthalmologists broadly indicated that use of nutritional supple- from retinal specialists (based on propor- ments could prevent more than 300,000 tion of all surgery performed that was cases of advanced AMD over the next 5 retinal surgery) in patient ascertainment. years (Bressler et al., 2003). The results of Despite these differences in patient selec- the present study, demonstrating increas- tion, their results combined with ours illus- es in resource utilization rates and costs trate important trends in AMD treatment by AMD type, suggest that interventions over time. The 3-year incidence of AMD preventing progression of AMD at earlier treated with laser photocoagulation was 2.3 stages could produce considerable cost per 1,000 in 1996-1998 (Javitt et al., 2003), savings in addition to beneficial patient corresponding to photocoagulation being outcomes. Policies associated with funding used as a treatment among 20 to 25 percent of AMD services, in particular second- of all Medicare AMD patients over this ary prevention services to prevent dis- period. Among the Medicare population in ease progression among individuals diag- our study, photocoagulation was received nosed with AMD, should be reviewed and by approximately 10.6 percent of wet AMD strengthened. Treatments that prevent or patients in 1999, 6.2 percent in 2000, and delay progression of AMD are likely have 5.0 percent in 2001. This decrease was substantial benefits in terms of improving accompanied by an increase in rates of patient well-being, maintaining vision, and PDT over our 3-year study period. decreasing medical care costs.

46 Health Care Financing Review/Spring 2006/Volume 27, Number 3 REFERENCES Frenkel, M.: Ophthalmologic Services as a Component of Medicare Spending. Archives of American Academy of Ophthalmology: Guideline— Ophthalmology 104(11):1609-1610, November 1986. Age-Related Macular Degeneration. San Francisco, Ishiko, S., Akiba, J., Horikawa, Y., et al.: Detection California. Internet address: http://www.guideline. of Drusen in the Fellow Eye of Japanese Patients gov/summary/summary.aspx?view_id=1&doc_ with Age-Related Macular Degeneration Using id=4349 (Accessed 2005.) Scanning Laser Ophthalmoscopy. Ophthalmology Bressler, N.M., Bressler, S.B., Congdon, N.G., et 109(11):2165-2169, November 2002. al.: Potential Public Health Impact of Age-Related Javitt, J.C., Zhou, Z., Maguire, M.G., et al.: Incidence Eye Disease Study Results. AREDS Report Number of Exudative Age-Related Macular Degeneration 11. Archives of Ophthalmology 121(11):1621-1624, Among Elderly Americans. Ophthalmology November 2003. 110(8):1534-1539, August 2003. Centers for Disease Control and Prevention: Macular Degeneration Partnership: Types of AMD. International Classification of Diseases, Ninth Internet Address: http://www.amd.org/site/Pag Revision, Clinical Modification (ICD-9-CM). Internet eServer?pagename=Types_of_AMD (Accessed address: http://www.cdc.gov/nchs/about/other- 2005.) act/icd9/abticd9.htm (Accessed 2005.) Morse, A.R., Yatzkan, E., Berberich, B., et al.: Acute Centers for Disease Control and Prevention: Care Hospital Utilization by Patients with Visual Prevalence of Visual Impairment and Selected Impairment. Archives of Ophthalmology 117(7):943- Eye Diseases Among Persons Aged >/=50 Years 949, July 1999. With and Without Diabetes—United States, 2002. O’Neill, C., Jamison, J., McCulloch, D., et al.: MMWR Morbidity and Mortality Weekly Report Age-Related Macular Degeneration: Cost-of-Illness 53(45):1069-1071, November 19, 2004. Issues. Drugs and Aging 18(4):233-241, 2001. Centers for Medicare & Medicaid Services: SAS Institute Inc.: SAS® Version 8.1. SAS Institute Healthcare Common Procedure Coding System Inc. Cary, NC. 2002. (HCPCS). Internet address: http://www.cms.hhs. gov/medicare/hcpcs/default.asp (Accessed 2005.) Vinding, T.: Visual Impairment of Age-Related Macular Degeneration. An Epidemiological Study Clemons, T.E., Chew, E.Y., Bressler, S.B., et of 1,000 Aged Individuals. Acta Ophthalmologica al.: National Eye Institute Visual Function Scandinavica 68(2):162-167, April 1990. Questionnaire in the Age-Related Eye Disease Study (AREDS). AREDS Report Number 10. Archives of Wang, J.J., Foran, S., Smith, W., et al.: Risk of Ophthalmology 121(2):211-217, February 2003. Age-Related Macular Degeneration in Eyes with Macular Drusen or Hyperpigmentation: The Ellwein, L.B., Friedlin, V., McBean, A.M., et al.: Use Blue Mountains Eye Study Cohort. Archives of of Eye Care Services Among the 1991 Medicare Ophthalmology 121(5):658-663, May 2003. Population. Ophthalmology 103(11):1732-1743, November 1996. Reprint Requests: Michael T. Halpern, M.D., Ph.D., Exponent Ellwein, L.B. and Urato, C.J.: Use of Eye Care Inc., 1800 Diagonal Road., Suite 300, Alexandria, VA 22314. and Associated Charges Among the Medicare E-mail: [email protected] Population: 1991-1998. Archives of Ophthalmology 120(6):804-811, June 2002. Fine, S.L., Berger, J.W., Maguire, M.G., et al.: Age-Related Macular Degeneration. New England Journal of Medicine 342(7):483-492, February 17, 2000.

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