Parkinson's Disease (PD) is rapidly increasing worldwide (1, 2) imposing a significant burden on patients' quality of life and creating substantial economic challenges for both individuals and healthcare systems. The prevalence of the disease has doubled in the last 25 years: estimates for 2019 indicate over 8.5 million people affected (3). In Italy a rate of 193 patients per 100,000 inhabitants, with an annual incidence of 23.1 cases per 100 thousand inhabitants, was documented in 2020 (2). As PD progresses, there is a notable shift in the management costs from the National Health System to the patient, leading to increased “out-of-pocket” expenses. These costs rise significantly in advanced stage of the disease, particularly when motor fluctuations emerge (4–8).

Deep brain stimulation (DBS) is a surgical procedure for the treatment of complicated phase of PD. It is a reversible, safe, and efficacious therapy for various movement disorders, achieved by modulating cerebral networks through high-frequency electrical stimulation delivered by implantable pulse generators (IPGs) (9, 10).

Given the growing economic constraints and the need for efficient management of patients with progressive diseases, healthcare systems, particularly within National Health Systems, have undergone restructuring. To ensure long-term sustainability, the adoption of cost-effective therapies that mitigate the socio-economic burden of these conditions is imperative. DBS has been demonstrated as a cost-effective treatment, as corroborated by recent systematic reviews (11–14).

Initially, DBS was implemented using non-rechargeable battery-powered IPGs (NR-IPGs). These devices, with a lifespan ranging from 2 to 6 years depending on stimulation parameters, battery type, target site and patient-specific clinical factors (15), require surgical replacement upon battery depletion. This necessitates additional invasive procedures, exposing patients to increased discomfort and heightened risks of complications such as infection, skin erosion, device malposition, and malfunction (16, 17). The introduction of rechargeable IPGs (R-IPGs) has significantly mitigated many of these risks (17). R-IPGs present numerous advantages, including a reduced incidence of clinical complications (18–20), fewer replacement surgeries, and decreased hospital admissions. Moreover, R-IPGs have been associated with potential cost savings when compared to NR-IPGs (21, 22).

To date, the majority of economic evaluations have focused on the cost-effectiveness of DBS combined with best medical therapy vs. best or standard medical therapy alone (23, 24). However, only a limited number of studies have investigated the potential economic benefits of rechargeable devices specifically (14, 25–27).

Currently, several R-IPGs are available on the market from different manufacturers (Medtronic, Dublin, IR; Boston Scientific, Marlborough, MA, USA; Abbott Neuromodulation Lake County, IL; USA), with device longevity ranging up to 25 years (Vercise Genus R16, Boston Scientific) (28). The sole economic analysis in the literature pertains to R-IPGs with a lifespan of 9 years (25), and there is a lack of data regarding the budgetary impact of devices with the longest battery life, considering time horizons already well established in clinical practice (15 years) and the lifespan of newer models with maximum longevity (25 years).

The objective of this study is to develop a budget impact analysis (BIA) comparing the costs of R-IPGs vs. NR-IPGs in DBS for PD, focusing on real-world data concerning battery replacements, related complications and hospitalization rates.

Direct and indirect costs of PD are rising sharply in line with the exponential growth of patients and the increasingly limited financial resources of the national health systems.

A 2016 Italian study (33) reported that the average total expenditure per capita for PD patients aged over 50 was €4,441. In a prior study (6), the total costs of PD were calculated to be €8,640 per patient over a 6-month period, with direct costs accounting for 70% of the total. Indirect costs are also significant highlighting various estimates of annual productivity losses (34, 35).

Considering the costs' impact related to DBS procedure in PD patients, many studies previously had analyzed the cost of the first implant and/or the subsequent replacements (14, 25–27). Due to the high cost of these devices, it is crucial to appropriate handling of DBS equipment costs, and evaluate within the appropriate time horizon considering the eventuality of repeat DBS procedures, adverse effects, and economic impacts upon medication use affected by DBS. There are different suppliers on the market who produce this equipment, and the prices are quite similar for the first implant full equipment but is important to highlight that the cost could vary in subsequent replacements considering different IPGs longevity among NR and R ones and different prices imposed by different manufactures (36). Nowadays, according to the different manufacturers, an R-IPG replacement should be considered after 10 years (Brio, Abbott), 15 years (Percept RC, Medtronic), or 25 years (Boston Scientific) (28). For most models, these time references do not necessarily correspond to complete battery depletion, whereas in other cases (Activa RC) the indicated time closely reflects the ERI status.

Across All DBS studies IPG replacement account for about 9% of the total cost of DBS therapy and proportionally increases over the lifetime of the patient (12).

Rizzi et al. (14) firstly compared the implantation costs of NR-IPGs to the estimated costs of R-IPGs over a follow-up period of 7.9 years (with IPGs replacement of an average of 1.5 times per patient). Cost analysis revealed an overall cost saving of 234,194 euros, including the costs of management of complications. The cost calculation, considering Italian mean life expectancy (47 years), found that the expected expenditure with NR-IPGs would have been 17,669,942 euros, and for R-IPGs of 11,751,754 with a saving of 5,918,188 euros. The average annual savings expected for each patient would be 905 euros.

According to Hitti et al. (25) this cost-saving effect would be 60,900$ over the course of 9 years. In a study by Perez et al. (26) rechargeable devices are estimated to reduce costs by 34%.

Retrospective data show that patients with NR-IPGs were older, had longer hospital stays, and required more neurological evaluations after first implant than R-IPG patients. This likely reflects that most NR devices were implanted early in our experience (2000–2012), when inclusion criteria differed (37) and advanced programming features—directional leads, broader stimulation parameters, and software for reconstructing the volume of activated tissue—were unavailable. In recent years (2012–present), R devices are mainly used, with refined selection criteria favoring younger patients with shorter disease duration (38) and the latest technological advancements.

A key factor favoring R-IPGs was their lower infection risk due to fewer replacements. DBS infections incur significant costs from hardware salvage, explantation, and replantation (39). Reported infection rates range from 0.7% to 6% for NR-IPGs (40, 41) vs. 2% for primary R-IPG implantation (21, 22). Our long-term data align, showing 6.03% for NR-IPGs and 2.12% for R-IPGs.

Patient preference is another key factor in choosing between the two devices (42). While neurologists worry that older patients may struggle with R-IPG recharging due to cognitive decline, technology unfamiliarity, or limited caregiver support, recent surveys show most manage it well, with few adverse events or therapy interruptions (25, 43). Our long-term R-IPG experience confirms this: 10/47 reported minor recharging issues, no sudden IPG depletion occurred, and 8/47 needed caregiver help. Additionally, 3/47 NR patients switched to R-IPGs despite advanced age (mean 72 years), long disease duration (mean 24 years), and cognitive challenges. Nevertheless, in the decision-making process, it should be kept in mind that if the patient or the healthcare facility responsible for their care is no longer able to manage regular recharging, elderly patients who still benefit from DBS therapy may need to consider switching to an NR-IPG.

The second part of our study involved a BIA comparing economic costs of R-IPG and NR-IPG batteries. The model shows the impact of using R-IPGs in our hospital. Figure 1 illustrates that every 3.8 years (based on NR-IPG replacement data), NR-IPG costs rise, while R-IPGs require only one replacement at battery exhaustion, modeled in two scenarios. Over time, R-IPGs become more cost-effective despite NR-IPGs offering short-term savings, including scenarios with equal initial hospitalization costs or hypothetical 5-year battery longevity.

These data are confirmed by Holm et al. (27) which, in a scenario modeled for a battery longevity calculated for 9 + 15 years (Extended RC Medtronic) found that R devices could reduce costs from 44 to 51%, in a 16-years horizon. Savings were greater with the 15-year compared with 9-year longevity IPGs. It is therefore likely that a R device with a longevity of 25 years could be even more economically advantageous than one with a longevity of 10 or 15 years.

Our model also assessed the economic impact of shifting to R-IPGs on hospitalization costs. For a single patient with an R-IPG over 25 years, a hospital would avoid 5 IPG replacements (–€71,584 per patient). This strategy also enhances hospital operational capacity, particularly in contexts of high demand and long waiting lists.

Considering the projected economic burden of Parkinson's in the coming years (44–46), these long-term projections are especially valuable, given differences in reimbursement systems across countries and the rapidly evolving public health economic landscape (21, 22).

In Italy, as in much of Europe, all device-assisted therapies (DAT), such as apomorphine or levodopa infusions, are now fully reimbursed. While DBS has a higher initial cost for neurosurgery and the stimulator system compared to infusion therapies [with an annual cost of €40,000 to €80,000 (47)], long-term projections show that DBS is cost-saving compared to other DATs (45, 46).

DBS equipment costs may change over time for both R- and NR-IPGs. A typical PD-DBS patient (aged 50–65) with a 25-year life expectancy (LE) may need 4–5 NR-IPGs. For PD onset between 40 and 64 years [LE estimated around 21 years (48)], a 25-year R-IPG is conceptually more favorable than 10- or 15-year devices. Our data also support this choice for patients with onset after 65, as a French study reported an LE of 16 years (17.8 for women, 16.1 for men) (49). In both age groups, our budget analysis shows a 25-year R-IPG is consistently less costly than 15-year R-IPGs

Compared to previous studies (14, 25–27), our study has several strengths and limitations. Its single-center design ensures uniform surgical techniques and postoperative DBS management but may limit generalizability. Major strengths include the large sample size, long-term follow-up, and budget calculations based on real-life data. Limitations include its retrospective nature, lack of detailed complication costs, and extrapolation of 18-year follow-up data to a 25-year economic horizon. Economic data reflect the longevity of the most commonly used device models, which may change in the next future. Extensive clinical experience exists for R-IPGs with up to 15-year battery life, whereas devices rated for 25 years are newer and less evaluated; actual lifespan may be shorter due to complications and other factors (14, 16). Developed from Italian clinical practice, findings may vary elsewhere, but are likely applicable across Europe, considering different device lifespans.

This study confirms that the economic savings of using a R system are evident in the short term and grow exponentially at both analyzed time points. This provides an important indication, together with increasingly emerging data (43, 50) of the agreeability of patients and caregivers, to prefer R devices in all PD-DBS patients regardless of age, disease duration and life expectation taking in account future costs related to disease progression.