Background: Knee osteoarthritis is a common condition that causes significant pain and disability, often leading patients to seek relief through self-medication (SM) [1]. However, while SM may offer temporary relief, it also carries substantial risks. Misuse of SM, including inappropriate drug use, excessive dosages, or interactions with other treatments, can lead to adverse effects and worsen the overall health of patients.

Objectives: This study aims to examine the misuse of SM in patients with knee osteoarthritis and to identify factors contributing to this behavior.

Methods: A cross-sectional study was conducted in the rheumatology department between October 2022 and February 2024. Data were collected through a telephone questionnaire. The included patients were followed for knee osteoarthritis without any associated rheumatic inflammatory pathologies. Patients were surveyed regarding their sociodemographic characteristics, personal medical history, and knee osteoarthritis-related features, as well as their SM practices. Knee osteoarthritis was assessed by pain intensity using the Visual Analog Scale (VAS pain) and functional impact using the Knee Injury and Osteoarthritis Outcome Score-Physical Function Shortform (KOOS-PS) with lower scores indicating more severe functional limitations. SM misuse was identified, and a univariate analysis was performed to determine the independent predictive factors of misuse. Statistical analysis was performed using SPSS software version 26. The significance level was set at p = 0.05.

Results: One hundred and four patients were included, with a mean age of 59.6 ± 9.9 years and a sex ratio (F/M) of 10.5. The level of education was distributed as follows: 32.7% were illiterate, 45.2% had a primary school level, 18.3% had a secondary school level, and 3.8% had a university level. The socio-economic level was low for 48% of the patients, and average for the others. Hypertension, dyslipidemia, and diabetes were the most frequently encountered comorbidities in patients, found in 39.4%, 30.8%, and 26.9% of cases, respectively. Seventeen percent of patients had a stomach disorder and/or a liver disorder. Eight percent had kidney disease and 6% had cardiovascular disease. Additionally, 21.2% of patients had at least three associated comorbidities. The concomitant medications, used for other chronic conditions and that may interact with analgesics, and/or nonsteroidal anti-inflammatory drugs (NSAIDs), were: anticoagulants (n=5), angiotensin-converting enzyme inhibitors (n=30), sulfonylureas (n=9), and diuretics (n=8). Knee osteoarthritis was bilateral in 76.9% of cases, with a unicompartmental involvement in 39.4% and a tricompartimental involvement in 30.8%. The mean duration of knee pain was 6.24 ± 4 years. The average VAS pain score was 5.39 ± 1.7, with a range from 2 to 9. The average KOOS-PS score was 66.6 ± 16%, with a range from 28.2% to 89.5%. One third (33.7%) of the patients were satisfied with the medical care for their knee osteoarthritis, 34.6% felt neutral and 31.7% were dissatisfied. The frequency of pharmacological SM use was 39.4%. NSAIDs were the most commonly used class (67.4%), followed by acetaminophen (46.5%), topical NSAIDs (37%), and finally opioid analgesics (16.3%). The lack of awareness regarding the side effects and contraindications of medications used in SM was observed in 61% of cases. Risky behaviors were detected in 56.1% of cases among patients who used SM. These behaviors included: using NSAIDs despite the existence of contraindication in 8 cases, risk of drug interactions with NSAIDs in 25 cases, the prolonged use of NSAIDs in 3 cases and of acetaminophen in 3 other cases. SM misuse was significantly higher among illiterate patients (Odds Ratio (OR) = 9.06; 95% Confidence interval (CI) = [1.01-81.15], p = 0.025). and among those experiencing higher pain levels (VAS > 5) (OR=8.4; 95% CI = [1.5-47.04], p=0.008). No significant association was found between SM misuse and age, gender, socio-economic status or functional impairment.

Conclusion: A significant proportion of patients used SM without appropriate awareness of the associated risks. Risky behaviors were prevalent, and misuse of SM was notably higher among illiterate patients and those experiencing higher pain levels. These findings highlight the need for targeted interventions to improve patient education, particularly among vulnerable groups, to reduce the risks associated with SM misuse.

REFERENCES: [1] Cui A, Li H, Wang D, Zhong J, Chen Y, Lu H. Global, regional prevalence, incidence and risk factors of knee osteoarthritis in population-based studies. EClinicalMedicine. 26 nov 2020;29-30:100587.

Acknowledgements: NIL.

Disclosure of Interests: None declared.

© The Authors 2025. This abstract is an open access article published in Annals of Rheumatic Diseases under the CC BY-NC-ND license ( http://creativecommons.org/licenses/by-nc-nd/4.0/ ). Neither EULAR nor the publisher make any representation as to the accuracy of the content. The authors are solely responsible for the content in their abstract including accuracy of the facts, statements, results, conclusion, citing resources etc.