Effect of Losartan on Patellar Cartilage Volume Among Patients With Knee Osteoarthritis

Abstract

Purpose Losartan previously in murine Osteoarthritis (OA) model displaying the heterozygous chondroplasia gene (cho/+), a col11a1 mutation shown reduced cartilage loss in temporomandibular joint (TMJ) condylar and knee joint articular cartilage (Osteoarthritis and Cartilage, 2019, 27; 676-686). Losartan is an angiotensin receptor blocker and an inhibitor of TGF-beta. This cross sectional study explores the effect of losartan on patellar cartilage volume in patients with knee osteoarthritis using publicly available database. Methods Using data from Osteoarthritis Initiative (OAI), we compared patellar cartilage volume in patients with and without losartan. A total of 4796 men and women aged 45-79 years were enrolled into the study primarily consisting of those with knee OA and those at high risk for developing knee OA. Our study focused on the progression sub cohort, which consisted of 1390 subjects with knee OA. This study used three measurement periods; baseline, 12 months and 24 months. Patients with missing data for entire series or part missing data and patients who were taking other angiotensin receptor blocker drugs excluded from analysis. Patients data then divided into losartan group and control group (patients without losartan). Specific data sets for the analysis included of demographics such age, sex, race (Clinical_FNOH, Enrollees), patient drug usage (MIF00), Magnetic Resonance Imaging (MRI) data sets on cartilage volume were used from KMRI_FNIH_Qcart_Biomediq00 (baseline), KMRI_FNIH_Qcart_Biomediq01 (12 months), and KMRI_FNIH_Qcart_Biomediq03 (24 months). The patellar cartilage volume variables were V00PatellarCartilage (baseline), V01PatellarCartilage (12 months) and V03PatellarCartilage (24 months). Additional protocol details are published and available on the internet (https://oai.epi-ucsf.org/datarelease/docs/StudyDesignProtocol.pdf). Results Our analysis of the progression sub cohort included a total of 85 (44 %) were men and 108 (56 %) women with symptomatic knee OA (Total n=193). Average age of the participants was 59.6 years (SD, 8.7 years; range, 45–78 years). The majority of the participants were Caucasian (n=142; 73.6 %) and African American (n=42; 21.8 %) (Table 1). Of the 193 patients included in analysis, 30 patients were taking losartan and remaining 163 patients were placed into control group. Mean cartilage volume for losartan and control groups at baseline, 12 months and 24 months are shown in figure 1. Over the period of two years, there was a progressive decline in cartilage volume in both groups. Our analysis show that there was no significant loss of cartilage volume with patients on losartan over baseline at 12 months (5 %) and 24 months (8 %) post enrollment. Patients without losartan showed significantly higher cartilage loss at 24 months post enrollment over baseline (~15 %, p≤ 0.05, Student's t-test assuming unequal variances). Conclusion This study suggests that losartan reduces loss of patellar cartilage in patients with knee osteoarthritis. Further analysis is needed to ascertain association of losartan and reduced loss of cartilage volume and beneficial effects of losartan in osteoarthritis.