Economic impact of inflammatory bowel disease in Alberta

This paper attempts to estimate the cost of inflammatory bowel disease (IBO) to the health care system of Alberta. In the 1015 patients responding to a questionnaire, two types of direct costs were compared to provincial averages; physicians' fees and hospital costs. Costs were calculated using the Alberta Health Care Insurance Plan prescribed billing races. The 15-to 24-year-old age group exhibited the highest annual physician fees. This was probably due to the high incidence rate of IBD in this group. The mean cost per patient-year for Crohn's disease was estimated to be $4400 and the mean cost for ulcerative colitis was estimated to be $3020; this did not include outpatient laboratory or radiological investigations, and as such represents an underestimation of the total costs to the health care system. However, only a small minority of the patients were using a large majority of the resources: for example, for both Crohn's and ulcerative colitis, 7% of the patients accounted for 69% of hospital days. The average hospital and physician associated costs declined markedly with duration of the disease. It is estimated that the future cost of IBO to the provincial health care system (the percentage of the provincial health care budget used to diagnose and treat IBO) will double from 1985 to 2000. This underscores the need for continued and expanded research into the cause and treatment of IBO, and the importance of maintaining a health care system which can respond to the needs of these patients.

A S THI:.COST Or I lf:ALTH CARI:.HAS become a substantial part of personal and government expenditure in Canada, interest in the cost of illnesses has developed in both the economic and medical communities.This raper attempts to estimate the cost of inflammatory bowel disease (IBO) to the health care system and the economy of the province of Alberta.The cost to the health care system is the direct cost of diagnosing and treating the disease which includes physician fees and hospital costs.The cost to the economy is the indirect cost of the illness that results from lost work days.The results from a recent epidemiological study of IBO in th is area of northern Canada ( l ) were used co predict the fucure number of cases and the economic impact of these patients.

METHODS
The area included in chis study was the northern half of the province of Alberta.which had a population of 1,295,360 people in 1981.Patients with PINC! !BECK Cl a/ Croh n's disease an d u lce rative coli tis were identified by a procedure described earlier (I).Their hospital and physicians' records were then reviewed to dete rmine what p rocedures they h ad undergone.Each of the p atients was sen t a question naire regard ing the num ber of docror visits per yea r, days hospitalized per yea r, days incapacitated per year an d ef- A wea l of 1015 of the 2430 selfadministered questionn aires (4 1.8'~' .,)were retu rned.The cost per patient-year was calculated using the A lberta Health Care Insurance Pla n bi lling rates ( 1985 ), which arc regu la ted by the provincial governmen t.The total cost was d ivided by the total nu mber of patien t-years.to determi ne the average patient-year cost in 1985 Canadian dollars.This aggregate approach is more suitable for estimating the cost of a specific ill ness than the Jisaggregacive approach of assigning a por tion of the total health b udget to an illness ( 2 ).The future estimates of the costof IBO were based on predicted numbers of patients, from known incidence and prevalence figu res, multiplied by the average wsts fo r Crohn's disease and ulcerative colitis.T he predicted num be r o f cases

RESULTS
As m igh t he expected, the cosr per year of health care for a person afflicted with Croh n's disease or ulcerative colitis is much higher than the provincial average per pers()n costs.The difference fo r p h ysicians• lee, ( Figure I) is most evident in the 15-r() 2 +vear-old age gr0u p where the cost for Croh n's disease is more than l 3 times the provincia l average a nd the cost of ulcerative colitis is almost eight times the average cost.For all age groups, the mean physician cost per patient-year was $ 1495 for Croh n's and $950 for u lcerative colitis, compa red wi th the provincial average of $207 per year T his physician cost did not include outpatient laboratory or radiological investigations.and as such represen ts a n underestimation of the total costs to the health care system.
IBO patie n ts also had much h igher costs than average for the other direct expense, hospitalization.The mean days in hospital per year were 7.4 3 for Croh n's and 5.30 for ulcerative coli tis compared with the provincial average of l. 44 days.The means fo r the disease groups arc not representative of the true situation as they were affected by outliers.A better p icture can be derived from Figure 2 wh ich shows that about 75% of the IBO patie n t population h ad not been in hos- pita! during the past year.Whatever the proportion of patients requiring h ospimlization, the total cost is substantial, $2905 per patient-year for Crohn's disease and $2070 for ulcerative colitis.From these results the total direct cost per patient-year for Crohn's is $4400 and $3020 for ulcerative colitis.For 1985. the total amount expended on physician and hospital costs fo r patients with either dis-L'a,L' 1s estimate<l at over $ 19 mdlion.The mean values for days incapacitated per year (Table 1) for both Crohn's discasc(26.l) and ulcerative colitis ( 17. 5) were also influenced by outliers.Figure 3 shows that over 50°1, of Crohn's and over 60"~ of ulcerative colitis patients did not lose ,,ny time from work (outside the home) due to lBD.As was the case with the hospital statistics, a minoriry of the patients was using a majority of the resources.Using known incidence and prevalence rates for the northern ha!( of Alberta ( l), the number:.. offuture case:.. of the diseases were estimated, together with estimates of direct p hysician costs (Table 2).lfincidencc rates continue unchanged and mortaliry from IBD remains low, then by the year 2000 the physician co:;ts to the Alberta Health Care Insurance Commission for the care of 12,120 Vol 2 No.2.Junc 1988 IBO patients would be at least $15.8 million at 1985 prices.However, the cost for h ealth care for patients with IBO is highest ea rly in the disease, falling markedly with duration of disease, both with respect to hospital (Figure 4) and physician costs (Figure 5).Although the number of admissions to hospital each year remains relatively stable over time ( Figure 6), the length of hospitalization tends to fall with duration of disec1sc (Figure 7).The continued care of these patients would then shift to the community, with patients consulting their doctor only slightly more than o nce per year (Figure 8).DISCUSSION lt is all but impossible to calculate the total cost of an illness to society; how ca n a dolla r value be put on a person's pain and suffermg?Therefore, the cost must be estimated using items which have a monetary value.Information on drug cost:; was not available for this study, which could be substantial in the treatment of chronic digestive d isord ers such as !BO, nor were dcrnib on laboratory fees for outpatient~.N,incthclc~s.from the available information it appears that the direct costs of IBD are high and will probably incrca,e.
The large number of physician costs 8 9 10 11 12 13 14 15 Duration of Disease (yr) Duration of Disease (yr) Figure 5) Effect uj d11ratl()n of IBD 011 awrnge doctor annual cost O'---"""-"""'--""'.._..=--~L...C>=---"""'--  Dura tion of Disease (yr) Figure 7) Effect of duration of IBD on at•erage day.1 in hospiwl periods in hospital desp ite continued need for hosptta lt zation (Figures 6 and  7) ;.md contin ued need to consu lt physicians on an annual basis (Figure 8).While most patients requ ire o nly outpatient treatment, a few of the more seriously affected people need intensive hospital treatment.For both diseases, 7% of the patien ts accou n ted for 69% of the total tim e in hospital.There was a similar situ ation for time incapacitated per year, w ith 20% of the patie n ts accounting for 89% of the total time lost.Again, a simi lar trend was observed in the Copen h agen studi es in chat 75% o f Crohn's patients and about90%of ulce rative colitis patients were capable of fulltime work (3,4).ln this study, 72% o f Crohn's patients and 82% of ulce rative  2).T h is increase is a reflectio n o f the growing preva lence of the disease in Alber ta.ln the year 2000 it is expected that there will be over 12,000 cases of 180.This underscores the need for continued and expa nd ed research into the cause, prevention and treatment of IBO.

Figure 4 )
Figure 4) E[fcci of duracion of 180 on average hospital annual cost

Figure 8 )
Figure 8) Effect of cl11rauo11 of I BD on annual t•isirs co a clocror