|Sections this chapter:|
Determining the economic impact of CKD on the healthcare system is challenging on several levels. The case definition is dependent on reported data. A biochemical definition would be the most quantitative, but health plan datasets rarely contain this information on a large scale. A definition of the CKD cohort using diagnosis codes, however, may represent only the more advanced — and thus most expensive — cases. In addition, CKD is a highly interactive disease, associated with cardiovascular disease (CVD), diabetes, stroke, and infectious complications.
Given these limitations, we have developed a method using diagnosis codes to create a point prevalent CKD cohort. In the 2009 ADR, "new" CKD patients were included in an attempt to produce a period prevalent cohort parallel to that created for the ESRD population. These patients, however, accounted for a disproportionate percentage of overall costs which could not be directly attributed to their CKD status. The reasons for this are numerous, but may include a high rate of acute kidney injury. This year we include only those patients classified as having CKD on January 1 of a given year, resulting in a true point prevalent cohort. When compared to last year's ADR, costs reported here for CKD patients are thus significantly lower, while those for non-CKD patients are higher. It is unclear which methodology most accurately depicts true CKD costs. Each has its strengths and weaknesses, and the differences seen with each method reflect the uncertainty involved in using claims to classify CKD.
We begin by comparing data from Medicare and the Taiwan Bureau of National Health Insurance, which both use the Medicare billing format, thus allowing for precise comparisons between the two countries. Diabetes is diagnosed in 22 and 18 percent of Medicare and Taiwanese patients, respectively, and CVD in 41 and 30 percent. (It is important to note that CVD in Taiwan is dominated by strokes, rather than the ischemic heart disease and congestive heart failure predominant in the U.S.) The CKD population recognized from diagnosis codes is also quite similar, at 6.8 and 5.4 percent. As mentioned elsewhere in the ADR, however, these numbers under-represent the total burden of CKD in older patients, suggesting that more advanced disease is being reported. The percentage of healthcare expenditures associated with CKD reaches 14 in the U.S., and 12 in Taiwan, illustrating the significant financial impact of the disease.
We next compare costs in the Medicare and younger employer group health plan populations, showing that overall costs per year reach $20,000 and nearly $17,000, respectively. Yearly costs for whites and African Americans with an additional diagnosis of diabetes or CHF reach $22,000–25,000 and $29,000–35,000.
Costs during the transition to ESRD are considerable, with the most striking occurring in the month of dialysis initiation — at nearly $15,000 for Medicare patients, and $32,000 in the EGHP population. And expenditures per person per month in the first six months on dialysis are two times higher for EGHP patients than for Medicare patients, which may reflect pricing issues. Medicare sets prices for dialysis procedures and ancillary services, while private health plans, with few providers and only 15 percent of treated patients, have little leverage to negotiate pricing. Patients with commercial coverage can thus generate considerably more margin for dialysis providers, offsetting costs of the Medicare population or increasing profits for the large commercial dialysis chains.
We introduce this year data from the Medicare Part D benefit, begun in 2006. Medication costs for patients with CKD, diabetes, and congestive heart failure combined reach $2,294 per year.
We conclude by further examining costs in the U.S. and Taiwan. In both populations, CKD is highly interactive with diabetes and CVD. Expenditures as individuals transition from CKD to ESRD are also similar, starting relatively low and then rising rapidly. These findings suggest that cost patterns for CKD in other high-income countries may be similar as well, and provide evidence that CKD patients have a significant impact on a nation's healthcare costs. In prior editions of the ADR we have illustrated that preventive care is at less than recommended levels in both the U.S. and Taiwan. This area clearly needs to be addressed, as inadequate blood pressure, lipid, and glycemic control may contribute to progressive kidney disease and thus to a greater number of individuals reaching ESRD.
Figure 9.1 Distribution of costs of point prevalent general (fee-for-service) Medicare &Taiwanese patients with diagnosed CKD, cardiovascular disease, &diabetes (see page 170 for analytical methods. Point prevalent general (fee-for-service) Medicare patients, &point prevalent patients from the 1 percent Taiwan National Health Insurance sample, age 65 &older, without ESRD. Diabetes, CVD, &CKD determined from claims; costs are for calendar year 2008)
Costs for African American Medicare patients with both CKD and congestive heart failure were 21.5 percent higher in 2008 than those for white patients with both diagnoses, at $35,009 compared to $28,809. Compared to those of patients in the earlier stages of CKD, costs for those with Stage 3–5 CKD were just 4.6 percent higher among whites, and nearly equal among African Americans. ? Figures 9.2–4; see page 170 for analytical methods. Point prevalent Medicare patients age 65 &older (9.2–4), &point prevalent MarketScan patients age 50–64 (9.2).
Figure 9.2 Overall PPPY costs in CKD patients, by CKD diagnosis code, dataset, &year
Overall per person per year (PPPY) costs in 2008 reached $19,752 for Medicare CKD patients, and $16,738 for those in the MarketScan database. Compared to those of patients with CKD of Stages 1–2, costs for those with Stage 3–5 CKD were 14.2 percent greater in the Medicare population, and 42.2 percent higher among MarketScan patients.
Figure 9.3 PPPY costs in Medicare CKD patients with diabetes, by CKD diagnosis code, race, &year
In the Medicare population with both CKD and diabetes, PPPY costs for African American patients reached $25,352 in 2008, nearly 17 percent higher than the $21,740 for whites. Costs for those with Stage 3–5 CKD were 9.9 percent greater for African Americans, and 11.4 percent higher for white patients, than costs for their counterparts in the earlier stages of the disease.
Figure 9.4 PPPY costs in Medicare CKD patients with CHF, by CKD diagnosis code, race, &year
Figure 9.5 Overall PPPM costs during the transition to ESRD, by dataset, 2007
Total per person per month (PPPM) costs in the month following ESRD initiation reached nearly $15,000 for Medicare patients in 2007, and $31,904 for those in the MarketScan program — 2.1 times greater.
Figure 9.6 PPPM inpatient costs during the transition to ESRD, by dataset, 2007
Inpatient costs in the month following ESRD initiation were 2.3 times greater for MarketScan patients, at $22,841 compared to $9,846. In the months following initiation, overall costs are twice as high in the MarketScan population, while inpatient costs are nearly equal, suggesting a greater use of outpatient services among MarketScan patients.
Figure 9.7 PPPM cardiovascular hosp. costs during the transition to ESRD, by dataset, 2007
PPPM costs for cardiovascular hospitalizations in the month following initiation reach $3,309 and $7,070 for Medicare and MarketScan patients, respectively.
Figure 9.8 PPPM infectious hosp. costs during the transition to ESRD, by dataset, 2007
Costs for hospitalizations related to infection reach $1,075 and $2,603 (the difference in this latter number compared to data reported in the 2009 ADR can be attributed to several hospitalizations with larger than average costs).
Figures 9.5–8; see page 172 for analytical methods. Incident Medicare (age 67 &older) &MarketScan (younger than 65) ESRD patients, 2007.
Table 9.a PPPM inpatient/outpatient &physician/supplier net costs ($) for CKD, by CKD diagnosis code, 2008 (see page 173 for analytical methods. Point prevalent Medicare patients age 65 &older, 2008)
Per person per month (PPPm) net costs are generally higher for Medicare patients with CKD of Stages 3–5 than for those with Stage 1–2 CKD. Total inpatient/outpatient costs in 2008, for example, reached nearly $1,190 for those in the later stages of CKD, 16.8 percent higher than the $1,018 incurred by patients in the early stages. Outpatient costs for EPO were 4.3 times greater for later-stage CKD, and costs for skilled nursing, home health, and hospice were 13.6, 11.2, and 20.0 percent higher, respectively.
Physician/supplier costs in 2008 totaled $456 for patients with Stage 3–5 CKD, 7.9 percent higher than the $422 for patients with Stage 1–2. Prescription medications accounted for 11.9 and 12.8 percent of these total costs, respectively.
Figure 9.9 Overall PPPY Part D expenditures, by year &at-risk group
Between 2006 and 2007, Medicare Part D net prescription drug costs per person per year (PPPY) rose 14.6 percent overall, and 12.9 percent for patients with CKD. Costs for CKD patients, however, reached $1,874, compared to just $1,262 in the general Medicare population. Costs rise with patient complexity, reaching $2,049 for those with CKD and diabetes, and $2,294 for those with an additional diagnosis of congestive heart failure (CHF). Costs for patients with no CKD, diabetes, or CHF rose 15.5 percent, but these patients were the least costly, at $1,109 PPPY.
Figure 9.10 PPPY Part D expenditures, by year &at-risk group: whites
Figure 9.11 PPPY Part D expenditures, by year &at-risk group: African Americans
At $2,081 PPPY, Part D drug costs in African American CKD patients were 12.3 percent greater in 2007 than costs among their white counterparts. Costs for African Americans with CKD, diabetes, and CHF reached $2,504 PPPY, 9.4 percent greater than the costs incurred by white patients with the same diagnoses. This is important in the context of the upcoming implementation of the ESRD prospective payment system, which will include certain oral drugs.
Not all drugs are covered through the Medicare Part D benefit. Notable exclusions particularly relevant to CKD include all over-the-counter medications (e.g. calcium carbonate) and vitamins and minerals (e.g. cholecalciferol, ergocalciferol). Oral vitamin D hormones (calcitriol, paricalcitol, doxercalciferol) are covered under the Part D benefit, but not all plans cover all available products.
Figures 9.9–11; see page 173 for analytical methods. Point prevalent Medicare patients. Costs are estimated net pay: sum of plan payment &low income subsidy.
Figure 9.12 Part D expenditures for Medicare &CKD
Total Part D Medicare expenditures reached $51.3 billion in 2007, and CKD patients accounted for $2.3 billion — 4.5 percent — of these costs.
Table 9.b Top 25 Part D prescription drugs used in the CKD population, by frequency &cost
Cardiovascular and diabetes medications were the Part D prescription drugs used most frequently by CKD patients in 2007, while medications for cardiovascular disease, gastrointestinal disease, diabetes, Alzheimer's, psychiatric diagnoses, asthma, pulmonary hypertension, and multiple myeloma topped the list in terms of expenditures. Epoetin alfa is not in the top 25 in terms of frequency, but accounts for the fourth highest expenditures under Medicare Part D, at more than $61 million in 2007.
Figure 9.12 &table 9.b; see page 173 for analytical methods. Includes Part D claims for all CKD patients, defined from claims on a point prevalent basis, for calendar years 2006 &2007. Costs are estimated net pay: sum of plan covered payments &low income subsidy payment amounts. Costs &counts in table obtained from 5 percent Medicare sample, &scaled up by a factor of 20 to estimate total Medicare CKD.
Figure 9.13 PPPM net costs for Part D-enrolled CKD pts: cardiovascular medications, 2007
Figure 9.14 PPPM net costs for Part D-enrolled CKD patients: lipid lowering agents, 2007
Figure 9.15 PPPM net costs for Part D-enrolled CKD patients: oral vitamin D, 2007
Figure 9.16 PPPM net costs for Part D-enrolled CKD pts with diabetes: diabetes agents, 2007
Figure 9.17 PPPM net costs for Part D-enrolled CKD patients: diuretics, 2007
In 2007, PPPM Part D net costs in the CKD population were similar for ACEIs/ARBs/renin inhibitors and beta blockers. Costs for dihydropyridine (DP) calcium-channel blockers were relatively high, particularly among African Americans. As with ESRD patients (see Volume Two, Chapter Five), statins are the predominant lipid lowering agent used in CKD patients; this is shown in their costs. Low oral vitamin D hormone costs reflect their infrequent use; among African Americans, however, costs are more than twice those incurred by whites and patients of other races. PPPM costs for insulin and thiazolidinediones (TZDs) far outweigh those of sulfonylureas and metformin. And costs of all diuretic therapies are relatively low, reflecting the availability of generics.
Figures 9.13–17; see page 173 for analytical methods. Point prevalent Medicare patients. Populations &costs estimated from the 5 percent Medicare sample; CKD defined from claims. Costs are estimated net pay: sum of plan payment &low income subsidy.
The burdens of ESRD in the U.S. and in Taiwan are among the heaviest in the world. The claims systems of the Taiwanese universal-coverage National Health Insurance (NHI) and the U.S. Medicare system are very similar, allowing us to directly compare people in these two countries who are at the greatest risk and who incur the highest costs — those age 65 and older. In 1993, costs for Medicare patients with CKD accounted for 3.8 percent of overall Medicare expenditures. By 2008, this had grown to 14.2 percent, in part reflecting growth in the number of recognized CKD patients. Costs for Taiwanese NHI patients with CKD, in contrast, have consistently accounted for 10–12 percent of total NHI expenditures since 2001. These differences may be due to the nature of the Taiwan NHI data, a closed sample based on the 2000 cohort and followed through 2008, unlike the open cohort of the Medicare population.
Figure 9.19 Overall expenditures for CKD &diabetes (DM) in the U.S. &Taiwan
Figure 9.20 Overall expenditures for CKD &cardiovascular disease (CVD) in the U.S. &Taiwan
The proportion of total costs incurred by NHI patients with CKD and diabetes or cardiovascular disease (CVD) has been relatively stable, in contrast to the steady increase seen for Medicare patients with the same diagnoses. In 2008, diabetic CKD patients accounted for 24.1 percent of total Medicare diabetes costs, slightly higher than the 21.5 percent of total NHI diabetes expenditures. Costs for CKD patients with CVD contributed 19.8 percent of total Medicare CVD expenditures in 2008, compared with 14.5 percent in Taiwan.
Figures 9.18–20; see page 173 for analytical methods. Point prevalent Medicare &NHI patients age 65 &older.
Figure 9.21 Per person per month (PPPM) expenditures for CKD in the U.S. &Taiwan, by at-risk group (see page 173 for analytical methods. Point prevalent Medicare &NHI patients age 65 &older.)
Compared to all Medicare patients, those with CKD and CVD have higher PPPM expenditures; costs are lower, in contrast, for those with CKD and diabetes but no CVD. In the Taiwan NHI database, multiplier effects are consistently shown for CKD patients with CVD, diabetes, or both. Uneven trends in the NHI data are due to the small size of the study sample.
Figure 9.22 Per person per month (PPPM) expenditures during the transition to ESRD in the U.S. &Taiwan, by age &dataset
Figure 9.23 Per person per month (PPPM) inpatient expenditures during the transition to ESRD in the U.S. &Taiwan, by age &dataset
These figures compare PPPM costs for U.S. and Taiwanese ESRD patients in the six months before and after the initiation of dialysis. Total costs rise prior to initiation, particularly in the last month, with hospitalization as the major factor driving this increase. Overall costs for Medicare patients peak in the first month of dialysis, while those for Taiwan NHI patients age 65 and older are highest in month two. The dialysis initiation period thus seems to be longer for Taiwan NHI patients with ESRD.
Figures 9.22–23; see page 173 for analytical methods. Incident Medicare patients age 67 &older, 2007, &incident MarketScan patients younger than 65, 2007; incident NHI patients, 2000–2008.