Differential healthcare costs in individuals with type 2 diabetes and incident chronic kidney disease in Hong Kong: a latent class trajectory analysis.

aims/hypothesisChronic kidney disease (CKD) represents a major and costly comorbidity in type 2 diabetes management. Identifying individuals with high healthcare costs due to CKD will support decision-making for early intervention. We used latent class analysis (LCA) to classify Chinese individuals with type 2 diabetes and incident CKD based on their demographic and clinical profiles.

methodsFor this study, 2886 individuals with type 2 diabetes and incident CKD and complete data for 42 attributes were selected from the prospective Hong Kong Diabetes Register cohort (2007-2019). We used LCA to select 14 variables to classify participants, followed by a hierarchical generalised linear mixed model to evaluate longitudinal healthcare costs among class memberships.

resultsDuring 109,784 person-years of follow-up, the incidence of CKD was 26.29 per 1000 person-years with a per-patient-per-year (PPPY) cost of US$4395 ± 11,947 (mean ± standard deviation). The four distinct classes used in the LCA based on baseline profiles were as follows: Class 1 (18.3%; PPPY: US$6087 ± 15,519), namely those who were young at onset (44.4 ± 10.3 years), had moderate comorbidities (25.6% had a moderate or high score on the Elixhauser Comorbidity Index [ECI]) and used multiple medications (90.2% used at least three medications); Class 2 (21.2%; PPPY: US$3822 ± 9816), namely those who had old-age onset (66.9 ± 6.9 years), had moderate comorbidities (27.8% had a moderate or high ECI score) and used multiple medications (70.7% used at least three medications); Class 3 (33.9%; PPPY: US$4260 ± 11,725), namely those who were middle-aged at onset (54.2 ± 10.0 years), had few comorbidities (14.0% had a moderate or high ECI score) and used few medications (15.6% used at least three medications); and Class 4 (26.5%; PPPY: US$3923 ± 10,957), namely those who were middle-aged at onset (54.1 ± 7.6 years), had moderate comorbidities (25.3% had a moderate or high ECI score) and used multiple medications (98.9% used at least three medications). Class 1 (young onset) and Class 3 (middle-aged onset) incurred the highest cost during the year of CKD onset, with those in Class 1 having more comorbidities than those in Class 3 at baseline. Multiple healthcare services contributed to the high healthcare costs in Class 1, with costs in Class 3 attributed mainly to post-CKD outpatient and psychiatric care. CONCLUSIONS/

interpretationThose with young-onset type 2 diabetes incurred the highest cost during the year of CKD onset. Individuals with middle-aged onset type 2 diabetes with fewer comorbidities and less intensified treatment at baseline also had subsequent increased healthcare costs.