Treatment costs of cystoid macular edema among patients following cataract surgery

Figures & data

Table 1 Demographic characteristics by procedure type

Characteristic	Beneficiaries with complex surgery	Beneficiaries with standard surgery	All beneficiaries
N	5,709	73,240	78,959
Age (frequency, %)
65–69 years	18.1	19.9	19.8
70–74 years	20.7	23.4	23.2
75–79 years	21.6	23.5	23.4
80–84 years	20.2	19.4	19.4
>84 years	19.4	13.8	14.2
Sex, female (%)	46.3	61.1	60.0
Race, white (%)	79.2	87.7	87.1

Table 2 Comorbid retinal conditions before cataract surgery

Condition (ICD-9)	Cases	Controls
N	2,003	76,946
Diabetes	26.0%	23.1%
Diabetic retinopathy	8.3%	3.7%
Background (362.01)	3.3%	1.9%
Proliferative (362.02)	1.4%	0.6%
Nonproliferative (362.03)	0.4%	0.2%
Mild nonproliferative (362.04)	0.7%	0.3%
Moderate nonproliferative (362.05)	0.4%	0.1%
Severe nonproliferative (362.06)	0.1%	0.0%
Multiple diabetic retinopathy diagnoses	1.9%	0.6%
Epiretinal membrane	8.4%	3.6%
Retinal vein occlusion	3.9%	0.7%
Two or more conditions listed previouslya	14.0%	2.5%
None of the conditions listed previously	39.3%	66.3%

Notes:

a All patients with diabetic retinopathy were also assumed to have diabetes (even if it was not expressed in claims). This refers to other combinations of conditions.

Abbreviation: ICD-9, International Classification of Diseases, Ninth Edition.

Table 3 Cases by comorbid retinal conditions

Condition (ICD-9)	% cases: complex	% cases: standard	% cases: all
N	5,709	73,240	78,949
Diabetes	4.1	2.7	2.9
Diabetic retinopathy	5.3	5.5	5.5
Background (362.01)	6.8	4.2	4.4
Proliferative (362.02)	0.0	6.4	5.7
Nonproliferative (362.03)	0.0	7.1	6.7
Mild nonproliferative (362.04)	4.5	5.0	5.0
Moderate nonproliferative (362.05)	0.0	7.5	7.0
Severe nonproliferative (362.06)	0.0	9.1	9.1
Multiple diabetic retinopathy diagnoses	8.7	7.9	7.9
Epiretinal membrane	10.4	5.5	5.7
Retinal vein occlusion	10.9	12.1	12.0
Two or more conditions listed previouslya	19.2	12.1	12.7
None of the conditions listed previously	2.8	1.4	1.5

Notes:

a All patients with diabetic retinopathy were also assumed to have diabetes (even if it was not expressed in claims). This refers to other combinations of conditions.

Abbreviation: ICD-9, International Classification of Diseases, ninth edition.

Table 4 Cases by comorbid retinal conditions: alternative definitions

Definitions	Base case	Alternatives
Preprocedure DME and ME	Not exclusion criterion	Not exclusion criterion	Exclusion criterion	Exclusion criterion
Postprocedure DME and ME	Not case	Case	Case	Not case
N	78,949	78,949	76,109	76,109
Diabetes	2.9%	7.8%	6.1%	2.3%
Diabetic retinopathy	5.5%	22.7%	9.3%	2.8%
Epiretinal membrane	5.7%	5.7%	3.7%	3.7%
Retinal vein occlusion	12.0%	12.0%	4.3%	4.3%
Two or more conditions listed previouslya	12.7%	33.8%	16.5%	6.8%
None of the conditions listed previously	1.5%	1.5%	1.3%	1.8%

Notes:

a All patients with diabetic retinopathy were also assumed to have diabetes (even if it was not expressed in claims). This refers to other combinations of conditions.

Abbreviations: DME, diabetic macular edema; ME, macular edema.

Table 5 Medicare claims (charges) and reimbursements (payments) for cataract patients

Type	Cases (n=2,003)			Controls (n=76,946)
	% with claim	Avg claim/6 M	Avg reimbursement/6 M	% with claim	Avg claim/6 M	Avg reimbursement/6 M
Inpatient care*	9.0	$5,540	$1,600	0.0	$6,820	$2,100
Outpatient care**	100.0	$21,860	$5,410	100.0	$16,020	$4,020
Totala,***	100.0	$27,340	$6,980	100.0	$22,790	$6,100

Notes:

a Totals may not equal the sums of inpatient and outpatient claims/payments due to averaging.

* P<0.05, cases versus controls, for differences in payments.

** P<0.001, cases versus controls, for differences in both claims and payments.

*** P<0.05, cases versus controls, for differences in claims. Currency is in USD as at 2014.

Abbreviations: Avg, average; M, months.

Table 6 Ophthalmic Medicare claims (charges) and reimbursements (payments) for cataract patients – all beneficiaries

Type	Cases (n=2,003)			Controls (n=76,946)
	% with claim	Avg claim/6 M	Avg reimbursement/6 M	% with claim	Avg claim/6	Avg reimbursement/6 M
Inpatient care	11.0	$0	$0	0.0	$10	$0
Outpatient care*	100.0	$10,330	$2,710	99.3	$5,910	$1,470
Totala,*	100.0	$10,410	$2,720	99.3	$5,950	$1,470

Notes:

a Totals may not equal the sums of inpatient and outpatient claims/payments due to averaging.

* P<0.001, for differences in both claims and payments. Currency is in USD as at 2014.

Abbreviations: Avg, average; M, months.