OP0197 The Number of Morbidities Drives the Health Care Expenditures and Presence of A Musculoskeletal Condition is Additionally Accountable for Higher Costs
Authors: A. van der Zee-Neuen, P. Putrik, S. Ramiro, A. Keszei, R. de Bie, A. Chorus, A. Boonen
Journal: Annals of the Rheumatic Diseases (2014)

<h3>Background</h3> In Europe, 70-80% of all healthcare expenses are attributable to chronic diseases and a large part of these are musculoskeletal conditions (MSKC). Having more than one disease (multimorbidity) is likely to increase the costs of care but little is known about the association of multimorbidity and health care costs and the specific role of MSKC as co-morbid disease in this association. <h3>Objectives</h3> To explore 1) whether the number of morbidities has an important association with costs of care and 2) whether MSKC have an additional impact when occurring as co-morbid disease. <h3>Methods</h3> In a Dutch cross-sectional study, 8904 subjects (&gt;18 years, random sample) completed a questionnaire on sociodemographic and lifestyle factors, self-reported physician-diagnosed diseases (MSKC, diabetes, cardiovascular diseases, cancer, migraine, respiratory, skin, mental and bowel conditions) and health care use (general practitioner, rheumatologist, orthopedist, physiotherapist, other specialists, hospitalization in regular/academic hospital and nursing home, home care and domestic help).The total health care costs (HCC) were computed for a three-months period using reference prices of the Dutch manual for pharmaco-economic health care evaluations 2010, accounting for inflation by Consumer Price Index. Missing values were imputed by means of multiple imputation. To deal with skewness, zero-inflated negative binomial regression (ZINB) models were computed to assess 1) the association of number of diseases and total HCC and 2) which disease or combination of diseases (in- or excluding MSKC) was associated with the largest increase of HCC using the healthy as reference. Models were adjusted for age, gender, education, origin (western vs. non-western), smoking status and BMI. For each of the different subgroups, based on number or combination of morbidities, raw and predicted 3-months HCC were presented for male/female patients. Predicted HCC were derived from the ZINB-models. <h3>Results</h3> MSKC occurred in 1766 cases (20%). Multimorbidity was present in 1722 cases (19%). HCC increased steeply with increasing number of morbidities (e.g. HCC for 1 morbidity were approximately 2 times higher than for the healthy, exp(β)=1.8 [1.7-2.0]). Compared to any other condition, MSKC was associated with higher HCC when occurring alone or when occurring as co-morbid disease. For example, when 2 morbidities other than MSKC were co-occurring HCC were approximately 2 times higher than in the healthy (exp(β)=2.2 [2.0-2.7]) while when one of the two morbidities was MSKC the costs were 3 times higher than in the healthy (exp(β)=3.0 [2.7-3.7]) (Table 1). <h3>Conclusions</h3> The total costs of health care consumption increase with increasing number of morbidities. MSKC are accountable for higher costs of care when compared to other diseases independent of the number of morbidities. These important findings deserve the attention of policy makers, especially by prioritizing MSKC in health care budgets. <h3>Disclosure of Interest</h3> None declared <h3>DOI</h3> 10.1136/annrheumdis-2014-eular.2218