The effect of age and sex on cost of inpatient facility encounters among patients with multiple sclerosis.
OBJECTIVE
To explore the effect of age and sex on cost of all-cause and multiple sclerosis (MS)-related inpatient facility encounters.


METHODS
Adult patients with an initial MS diagnosis were identified from a national managed-care database (IMS LifeLink Health Plans Database). The analysis included newly diagnosed MS patients with 12 months insurance eligibility before and after their first MS diagnosis. Inpatient facility encounters (stays) were analyzed for all-cause and MS-related events (ICD-9-CM = 340.XX), other demyelinating CNS disease (ICD-9-CM = 341.XX), rehabilitation (ICD-9-CM = V57.89), and a group of symptom-related diagnoses. Costs and length of stay were evaluated using a general linear model controlling for age and sex.


RESULTS
A total of 57,236 patients met study criteria; 74.3% were female. Mean age for females was 45.5 years and for males it was 47.5 years. In total, 17.0% had an all-cause inpatient stay in the 360-day post index, and 3.2% had an in patient stay with a MS relapse-related diagnosis as primary discharge diagnosis. Additional MS-related diagnoses that led to inpatient stays included other demyelinating CNS disease (0.3%), symptom-related diagnoses (1.0%), and rehabilitation (1.1%). All-cause inpatient cost was higher for males vs females across all age groups; however, cost for females increased at a greater rate as age increased (p = 0.0007). Symptom-related inpatient cost was flat for males, was lower for females than males at an average age of 30, and was greater for females than males at an average age of 60 (p = 0.0199). Cost for MS inpatient stays ($11,931), other demyelinating CNS-related stays ($14,931), and rehabilitation ($23,643) did not differ by age and sex. The average cost for any MS-related relapse inpatient stay was $13,761 and varied with increasing age (p < 0.0001).


CONCLUSIONS
Burden of illness for relapse among MS patients is substantial. Costs vary by age and sex depending on the discharge diagnosis. Inclusion of symptom-related and rehabilitation inpatient stays may account for an under-recognized proportion of total expenditures.
a a Independent Research Consultant , Saint Helena Island , SC , USA.
C M
CM
Kozma
D M
DM
Meletiche
A L
AL
Phillips
D000328:Adult; D000367:Age Factors; D005260:Female; D005102:Health Expenditures / Q000706:statistics & numerical data*; D006801:Humans; D007297:Inpatients; D007345:Insurance Claim Review; D019458:Insurance Coverage; D007348:Insurance, Health; D007902:Length of Stay / Q000191:economics*; D008297:Male; D008875:Middle Aged; D017059:Models, Econometric; D009103:Multiple Sclerosis / Q000191:economics*; D012008:Recurrence; D012189:Retrospective Studies; D012737:Sex Factors
Acute care; Costs; Disease modifying drug (DMD); Inpatient stays; Multiple sclerosis; Relapse