Cost-effectiveness analysis of the Parkinson's KinetiGraph and clinical assessment in the management of Parkinson's disease

Aims The Parkinson's KinetiGraph (PKG) is a wrist-worn movement recording system that collates continuous, objective, data during daily activities in people with Parkinson's disease (PD) providing a report for clinicians. This study explores the cost-effectiveness of adding the PKG to routine PD assessments. Methods A de novo Markov model of three health states: uncontrolled, controlled and death compared PKG plus routine assessment by a Movement Disease Specialist (MDS) versus routine assessment. Uncontrolled and controlled states were based on the Movement Disorder Society - Unified Parkinson's Disease Rating Scale (MDS-UPDRS) II and III scores. The transition between health states was dependent on improvement in MDS-UPDRS II and III, and transition to death state on all cause-mortality and PD-specific relative mortality risk. Markov cycle length was yearly beyond year 1 and lifetime horizon 22 years. Limitations PKG evidence incorporated in this analysis is based on findings from one clinical trial. Health state utilities were mapped and the probability of patients progressing from uncontrolled to controlled health state at the second visit and beyond was derived from a bootstrap method which assumed a normal distribution for MDS-UPDRS. Results The addition of the PKG to usual PD assessments is a cost-effective intervention. PKG plus routine assessment is associated with lower total costs compared to routine assessment (141,950 pound versus 159,312) pound and improved quality-adjusted life years (7.88 versus 7.61), resulting in an incremental cost-effectiveness ratio of -64,978.99 pound and a net monetary benefit of 22,706.37 pound using a 20,000 pound threshold. Results were robust across sensitivity and scenario analyses. Conclusions Management of PD involves monitoring and evaluation of symptoms to assess disease progression and ensure appropriate treatment choices. Adding the PKG to clinical assessment in routine care allows for improved and objective identification of PD motor symptoms which can be used in clinical decision making to improve patient outcomes. PLAIN LANGUAGE SUMMARY Hospital doctors caring for people with Parkinson's disease (PwP) regularly monitor and assess their patients' symptoms, relying on patient recall and patient-completed diaries to find out about current symptoms, which can be unreliable. The Parkinson's KinetiGraph (PKG) is a wrist-worn device that collects continuous information on movement in PwP. A report is then provided to the patient's Consultant helping them to understand the PwP's symptoms and make decisions about changing medication to improve symptom control. An economic model compared asking patients to wear a PKG device for 6 days before their check-up appointment with their Consultant with usual check-up without the PKG. Information from a clinical trial exploring the use of PKG provided data on Movement Disorder Society - Unified Parkinson's Disease Rating Scale (MDS-UPDRS) II and III scores, which were used in the model to predict improvements in quality of life and whether PwP had controlled or uncontrolled disease. The model showed that addition of PKG to usual check-ups is a cost-effective approach. Use of the PKG reduced costs (141,950 pound versus 159,312 pound for usual check-ups) and had a positive impact on quality and quantity of life as measured by quality adjusted life years (7.88 versus 7.61). This study shows that adding the PKG to routine check-ups allows Consultants to accurately assess movement (or motor) symptoms in PwP, which can then be used to ensure optimal mediation choice and improve patient outcomes.