(118) Ethnicity and polypharmacy in people with chronic kidney disease: a pharmacoepidemiologic perspective

Background: People living with chronic kidney disease (CKD) take many medications, increasing the risk of polypharmacy. With comorbidities greater in people from minority ethnicities, it is important to understand how the prevalence of polypharmacy in CKD differs across different ethnicities in the UK.

Objectives: 1. To establish the prevalence of polypharmacy and excessive polypharmacy between different CKD stages and in people without CKD.
2. To identify if ethnicity increases the likelihood of polypharmacy.

Methods: Adults living with, including those on dialysis and kidney transplant recipients (KTRs), and without CKD (non-CKD) were recruited as part of a multi-site cross-sectional study conducted in the UK. Clinical information including comorbidities and medication use was extracted from medical records. Self-reported ethnicity was categorised as White-British, South Asian, and Other. Data were analysed to examine the differences between the following medication categories across CKD stages: no polypharmacy, 0-4 medications; polypharmacy, 5-9 medications; and excessive polypharmacy, ≥10 medications. The effect of ethnicity and polypharmacy was evaluated using binary logistic regression modelling (adjusted for age, sex, and CKD stage). Data are shown as an odds ratio (OR) with 95% confidence interval [CI].

Results: 1426 adults living with CKD and 853 without CKD were included. The mean age was 56.0±17.8 years and 47.6% were male. 73.7% were White British; 11.1% were South Asian; and 15.1% were Other.
The mean number of medications increased as CKD progressed: non-CKD: 0.8±1.6, stage 1-2: 3.2±2.7, stage 3: 6.4±3.9, stage 4: 8.0±3.7, stage 5: 7.6±3.9, peritoneal dialysis (PD): 10.2±2.1, haemodialysis (HD): 9.2±3.6, and KTRs: 8.7±3.4.
Polypharmacy prevalence increased as kidney function worsened: non-CKD (4.2%), stage 1-2 (27.8%), stage 3 (48.9%), stage 4 (43.3%), stage 5 (53.3%), PD (25.0%), HD (41.0%) and KTRs (45.2%). Excess polypharmacy was reported as follows: non-CKD (0.5%), stage 1-2 (1.4%), stage 3 (19.8%), stage 4 (36.6%), stage 5 (28.9%), PD (75.0%), HD (48.9%), and KTRs (43.0%).
The prevalence of polypharmacy in each ethnic group was ~80%. Ethnicity did not increase the likelihood of polypharmacy. Compared to White British, South Asians (OR: 1.43, 95% CI 0.87 to 2.35, P=.159) or other ethnicities (OR: 1.54, 95% CI 0.98 to 2.40, P=.060) were not more likely to have polypharmacy.

Conclusions: The prevalence of polypharmacy was similar in different ethnicities. The limited number of non-White participants makes generalisation to other ethnicities difficult. Irrespective, polypharmacy remains highly prevalent and an important clinical problem.