An ageing population leads to increasing prevalence of age-related chronic conditions that present challenges to the health-care services. Despite this, in countries including Ireland, little is known about the health-care impact of conditions such as osteoarthritis or rheumatoid arthritis amongst older adults.A series of count models are developed to investigate the incremental health-care usage of individuals with either osteoarthritis or rheumatoid arthritis on the use of general practitioners (GP) services, outpatients' services, accident and emergency visits and inpatient nights.Both types of arthritic conditions lead to increased usage of GP and outpatients' services but not other hospital services. Differences in entitlements to care, as captured by the presence of a medical card in Ireland, lead to different health-care usage among arthritis sufferers. Translating the additional utilization into cost suggests a combined incremental annual cost of both types of arthritis of a,not sign13.6 million.Osteoarthritis and rheumatoid arthritis present challenges to health-care services in the context of an ageing population. In the case of Ireland the burden falls predominantly on primary health-care and outpatient services. Within the context of changing health-care service provision in Ireland, the results of this study have implications for future planning of service delivery.