The Critical Role of Phlebolymphedema in Cellulitis Associated with Lymphedema: its Incidence and Economic Impact in a Large Real-World Population.

OBJECTIVE: The aims of this study were: to define the incidence of cellulitis in lymphedema (LED) patients overall and relate this to the etiology of LED; to determine how this rate might be affected by recurrence of cellulitis; to quantify the contemporary economic burden of treatment. Understanding these factors is essential in developing targeted cellulitis prevention strategies and reducing healthcare costs.

METHODS: The IBM MarketScan® Research Database was examined from April 2013 - March 2019 for patients with a new diagnosis of LED (n=85,601). Based on ICD-9/ICD-10 diagnosis codes, the incidence and cost of cellulitis were ascertained during the 3-year follow-up period. Incidence rates (per 100 patient-years [PYs]) and cost (per patient per year) of cellulitis were evaluated among all LED patients and within subgroups of LED etiologies.

RESULTS: Among the three most common morbidities associated with LED (breast cancer related lymphedema [BCRL], N=17,954 (20.97%); gynecological cancer related LED [GCRL], N=1,256 (1.47%); and Phlebolymphedema [PLED], N=8,406 (9.82%), rates of cellulitis were markedly lower for BCRL (8.9, CI [8.7, 9.2]) and GCRL (14.8, CI [13.4, 16.4]), versus PLED (47.7, CI [46.7, 48.8]). Patients with a history of cellulitis had markedly higher cellulitis rates during follow-up than those without- overall, 74.0 vs. 16.4; BCRL, 42.9 CI [39.7, 46.3] vs. 7.6 CI [ 7.3, 7.9]; GCRL, 67.5, CI [56.4, 80.8] vs. 11.0, CI [9.8, 12.4]; and PLED 81.7, CI [79.4, 84.1] vs. 30.4, CI [29.4, 31.4] respectively. The mean $/patient/year of cellulitis-related costs for a patient with PLED ($2836, 95% CI [2,395-3,471]) was significantly greater than that for BCRL ($503, 95% CI [212-1,387] and GCRL ($609, 95% CI [244-1,314]).

CONCLUSION: The incidence of cellulitis associated with LED varies by etiology of LED. PLED has the highest rates of both an initial cellulitis episode and recurrent cellulitis events. Additionally, PLED has one of the largest cellulitis-related total cost per patient per year. Prevention, as well as early identification and treatment of PLED-associated-cellulitis could significantly decrease healthcare costs and improve patient quality of life.