Journal of Medical Academics
Volume 6 | Issue 2 | Year 2023

Assessment of Compliance of Glucosamine and Chondroitin Sulfate in Patients with Early Osteoarthritis of Knee

Parikshat Gopal1, Nikhil Sood2, Rupesh Prasad3

1Department of Orthopaedic Surgery, Army College of Medical Sciences, Delhi, India

2Department of Orthopaedic Surgery, Army Hospital Research and Referral, Delhi, India

3Department of Orthopaedic Surgery, Military Hospital Jodhpur, Jodhpur, Rajasthan, India

Corresponding Author: Rupesh Prasad, Department of Orthopaedic Surgery, Military Hospital Jodhpur, Jodhpur, Rajasthan, India, Phone: +91 8399905219, e-mail:

Received: 31 October 2023; Accepted: 21 November 202; Published on: 30 December 2023


Background: Osteoarthritis (OA) is one of the leading causes of knee disability. Depending upon the disease’s stages, various management modalities are available with varying grades of success. However, being degenerative and gradually progressive disease compliance to the treatment has a significant role in the outcome.

Materials and methods: This prospective observational study was carried out at a tertiary care orthopedic center to assess the level of compliance to tablet glucosamine and chondroitin sulfate tablets in subjects with early OA. Around 50 consecutive issues visiting the outpatient Department (OPD) of Orthopedics at Base Hospital, Delhi were included in the study after clinical and radiological confirmation of the diagnosis. Patients were advised to tablet glucosamine and chondroitin sulfate and followed up for 12 weeks. The Morisky Scale Questionnaire assessed compliance with the prescribed medication.

Results: This study confirms poor compliance with the prescribed medication among geriatric subjects with early OA. Various other factors, such as literacy level, family status, functional status, associated medical illnesses, daily medicinal load, and awareness about the disease, significantly impact the patient’s compliance.

How to cite this article: Gopal P, Sood N, Prasad R. Assessment of Compliance of Glucosamine and Chondroitin Sulfate in Patients with Early Osteoarthritis of Knee. J Med Acad 2023;6(2):53–57.

Source of support: Nil

Conflict of interest: None

Patient consent statement: The author(s) have obtained written informed consent from the patient for publication of the case report details and related images.

Keywords: Compliance, Early osteoarthritis of knee, Glucosamine and chondroitin sulfate


Osteoarthritis (OA) is one of the most common geriatric problems, which not only increases the burden on the healthcare system but also hampers the quality of life of the patient.1 Prevalence of OA of the knee joint is very common in the geriatric population. This condition results from mechanical, metabolic, genetic, and other influences. Manifestation ranges from mild discomfort in the knee to a serious incapacitating condition leading to the inability to perform daily activities. Depending upon the stage of the disease and the lifestyle of the patient, there are various treatment modalities available targeted at pain management, delay of progression of degeneration, and the replacement of the articular surface with the prosthesis [total knee replacement (TKR) surgeries and unicondylar knee replacement (UKR)].

Amongst analgesics, the nonsteroidal anti-inflammatory drugs (NSAIDs) are most commonly used to treat pain; however, their indiscriminate use results in gastrointestinal tract as well as renal system side effects, especially in the elderly population.2,3 Due to the side effect profile of NSAIDS, various other pharmacological products have been experimented with s the basic pathology in OA is degeneration of the articular cartilage, glucosamine and chondroitin sulfate were introduced to prevent wear and tear. The articular cartilage of the joint is made up of glycosaminoglycans and proteoglycans, which are formed by glucosamine. Chondroitin is a part of proteoglycans of articular cartilage. Both of them have antiarthritic and anti-inflammatory activities.4,5 A meta-analysis by McAlindon et al. demonstrated pain alleviation in patients with OA after administration of glucosamine and chondroitin sulfate.6 However, it requires a period of prolonged and regular compliance and the combined approach with lifestyle modification as well as supervised physiotherapy.

The majority of the time, OA is associated with advanced age, and compliance with the protocol is always an issue leading to poor patient satisfaction due to inadequate treatment. Chronic diseases need long-term medication with multiple drugs. This results in poor compliance because of many reasons, namely difficult to understand regimen, high cost of medication, drug interactions, side effects of therapy, poor family support system, elderly population, and forgetfulness. This poor compliance is up to 50% in the general population and ranges from 47 to 90% in the elderly population.7 This raises serious concern, especially in the elderly population, leading to the worsening of the condition.8

There is ample literature available to find out problem-based compliance rates in the elderly population.9 This study was performed to find compliance with medications in knee OA and factors affecting it.


This study to assess the level of compliance to tablet glucosamine and chondroitin sulfate in subjects with early OA was carried out at a tertiary orthopedic center.

Approval was obtained from the Institutional Ethics Committee. Around 50 consecutive patients with early knee OA consulting the Outpatient Department (OPD) of Orthopedics at Base Hospital, Delhi, India, were included in the study after thorough assessment and diagnosis.

Patients were included in the study by simple random sampling method. Consent was taken from all the patients in the language they understood (as per good clinical practice guidelines).

Diagnosis of early OA of the knee was made on the guidelines of the American College of Rheumatology (ACR) and Kellgren–Lawrence radiological classification of OA.10

Patients were evaluated by taking history, clinical examination, and radiological assessment of the stage of the disease. Patients who fulfilled the inclusion criteria were included in the study.

Inclusion Criteria

  • All of the patients visiting OPD have clinical and radiological fulfillment of the criterion of early OA.
  • Patients are willing to follow the rehabilitation program.
  • Patients without cognitive impairment had not been diagnosed with dementia.
  • Patients are willing to give consent and to be part of the study.

Exclusion Criteria

  • Patients with inflammatory arthropathy like rheumatoid arthritis, psoriatic arthritis, etc.
  • Severe cognitive impairment, dementia, or patient too ill to participate.
  • Patients with advanced OA knee.
  • Patients are unwilling to follow rehabilitation protocol.

A thorough clinical history of all the patients was taken, focusing not only on the knee complaints but also on other ailments like features of inflammatory arthropathy, trauma, other joint involvement, other comorbidities like hypertension, diabetes, coronary artery disease, pulmonary diseases, and previous surgeries upon the knee.

A clinical diagnosis of OA was made based on the ACR guidelines, and a thorough examination was done to look for the stage of the disease. A knee examination was done and the severity of the knee was assessed objectively, which included swelling, deformities, if any, tenderness, rise in local temperature, crepitus, joint effusion, muscle wasting, and range of movement.

Serum uric acid, erythrocyte sedimentation rate, C-reactive protein, and rheumatoid factor were assessed in suspected patients to exclude patients with inflammatory arthropathy at the beginning of the study. Radiological classification of the stage of disease was done by taking out the knee radiographs in anteroposterior view (weight-bearing), lateral and skyline view. As per Kellgren–Lawrence classification, the stage of disease was categorized into grades 0–IV. The patients with advanced OA, that is, grades III and IV, were rejected.

All of the patients were primarily educated about the course of the disease as well as the management protocol of it. Patients were enrolled for the muscle training and rehabilitation protocol consisting of active quadriceps and hamstring strengthening exercises (explained to each of them and supervised for initial few days), knee range of motion exercises, lifestyle modification like avoidance of squatting, excessive stair climbing (>10 flights stairs most of the days) and jumping/running activities. Also, tablet glucosamine sulfate 250 + chondroitin sulfate 200 mg twice a day was given. All patients were asked to avoid any NSAIDs and told to take tablet paracetamol only if needed.

Patients were followed up at the end of 12 weeks from the day of enrolment into the study as the effect of glucosamine and chondroitin sulfate is observed over this duration. The compliance with the prescribed medications was assessed by the Morisky scale questionnaire11 at 12 weeks of medication. At 12 weeks, interviews were conducted in the OPD complex targeting to find out factors affecting the compliance rate. Patients were asked about their understanding of disease conditions and medication dosage. Side effects of medication, if any, were recorded. They were also asked about their family support system.

Data was collected on an excel spreadsheet and analyzed using the Chi-squared test and multinomial logistic regression (Figs 1 and 2).

Fig. 1A to D: Showing X-ray depiction of Kellgren–Lawrence system of OA knee. (A) Grade I shows doubtful narrowing of joint space and possible osteophytic lipping; (B) Grade II shows definite osteophytes and possible narrowing of joint space; (C) Grade III shows multiple osteophytes, definite narrowing of joint space, small pseudocystic areas with sclerotic walls and possible deformity of bony contour; (D) Grade IV shows large osteophytes, marked narrowing of joint space, severe sclerosis, and definite deformity of bony contour

Fig. 2: Showing gender distribution of the study—females (56%) and males (44%)


Out of 50 enrolled patients, 44% (22) were male and 56% (28) were female. The average age of the study population was 51.06 ± 9.44 years (Table 1).

Table 1: Showing comorbidity profile of study population
Comorbidity Number of patients (n) Percentage
Hypertension 6 12%
Diabetes mellitus type 2 3 6%
Hypertension + diabetes type 2 5 10%
Hypertension + CAD 2 4%
Others (bronchial asthma, stroke–recovered, and parkinsonism) 3 6%

Bold values depict number of comorbidities leading to increase in number of drugs taken by patients and hence influencing compliance

Almost 38% of patients had comorbidities (medical illnesses) (Table 2), and they had prescription slips with either one or multiple drugs, mainly oral.

Table 2: Depicting level of compliance of study population with medication based on MMAS
Level of compliance* n (%)
Good 23 (46)
Moderate 18 (36)
Poor 9 (18)

The functional status of the study subjects based on objective assessment has shown that the majority of the subjects, 32 patients (64%), had no functional disability, 14 patients (28%) had a visual disability (10 had hypermetropia, and 4 had myopia; all were compensated with spectacles), four patients (08%) had difficulty in hearing.

Compliance level was measured as per the Modified Morisky Adherence Scale (MMAS).

The factors affecting medication compliance are well depicted in Table 3.

Table 3: Depicts factors affecting compliance with medication with p-value. MMAS: <6 = poor, 6–7= moderate, 8 = good
Factor/variable Compliance level p-value*
Poor Moderate Good
Age 40–50 4 (10.71) 9 (32.14) 15 (53.57) <0.05
50–60 8 (36.36) 9 (40.90) 5 (22.72)
Gender Male 3 (13.63) 7 (31.81) 11 (50) 0.141
Female 8 (28.57) 10 (35.71) 10 (35.71)
Educational status Illiterate 3 (30) 4 (40) 3 (30) 0.002
Pre/middle/high school 4 (16) 8 (32) 13 (52)
Diploma/graduate/postgraduate 01 (6.6) 7 (46.66) 7 (46.66)
Family status Living alone 12 (54.54) 6 (27.27) 4 (18.18) 0.001
With family 5 (17.85) 13 (46.42) 12 (42.85)
Functional status No impairment 4 (12.5) 11 (34.37) 17 (53.12) 0.001
Impairment of vision 6 (42.85) 5 (35.71) 3 (21.42)
Hearing impairment 1 (25) 2 (50) 1 (25)
Number of illnesses Single 1 (8.3) 3 (25.00) 8 (66.66) 0.001
Multiple 2 (28.57) 2 (28.57) 3 (42.85)
Number of medications Up to 3 1 (9.09) 4 (36.36) 6 (54.54) 0.001
>3 4 (50.00) 3 (37.5) 1 (12.5)
Awareness about the diseases Yes 8 (21.05) 13 (34.21) 17 (44.73) 0.001
No 9 (75) 3 (25.00) 0 (0.00)


Osteoarthritis (OA) knee is a very common and disabling condition. Being a progressive degenerative disease, its management requires a prolonged and regular follow-up. Due to its chronic nature, it is usually overlapped with other comorbidities along its course. The treatment modalities for the management are wisely chosen depending on the stage of the disease and the patient’s requirements.12,13 The goal of treatment is to have a painless joint, allowing one to perform routine activities.

This study was done to assess various factors affecting compliance with glucosamine and chondroitin sulfate tablets in patients with early OA. The results of this study are similar to a few other studies.14,15 Good compliance was seen in 53.57% of patients of age-group 40–50 years, 22.72% in age between 50 and 60 years. The level of compliance was poor in 10.71% of subjects of the 40–50 years age-group and 36.36% above 50 years. The findings of this study suggest decreasing compliance with increasing age, and it is statistically significant. Reason can be numerous age-related physical as well as mental limitations.16,17 A statistically significant positive correlation was observed between educational level and compliance rate. Hence, educating patients well about the condition and importance of medication increases compliance rate.18,19 It was also found that patients staying with family adhere to treatment protocol, as with previously done studies.20

Functional disability leads to poor compliance, and this was statistically significant, especially visual impairment.21 This may be because of the inability to read prescription slips or drug strips.

Good compliance was seen in subjects with a single illness compared to multiple illnesses, and the difference was highly significant. An increased number of ailments and a high cost of medicine, is correlated with a poor compliance rate. Also, patients with a single illness are more compliant with the medication given.22

Based on the above findings, solutions can be formulated to resolve poor compliance rates. This includes proper education of the patient, regular follow-up, simplified fixed drug regimen, educating family members as well, etc. The use of calendars and mobile phone reminders can also increase compliance rate.


As it was a service hospital OPD-based study carried out with a small group of population and over a limited period, extrapolation is not possible, and the study may not be representative of patients from all socioeconomic backgrounds.


This study confirms the existence of poor compliance to prescribed medication (glucosamine and chondroitin sulfate) among geriatric subjects with early OA. However, there was variation in the reported rates of level of compliance (poor/moderate/good compliance), probably due to differences in study methods. Various other factors like literacy level, family status, functional status, associated medical illnesses, daily medicinal load, and awareness about disease possess a significant impact on the compliance of the patient.

Literature based on medication and compliance is very few in developing countries, and hence, it needs more studies in this area.


Parikshat Gopal

Rupesh Prasad


1. Silverstein FE, Graham DY, Senior JR, et al. Misoprostol reduces serious gastrointestinal complications in patients with rheumatoid arthritis receiving NSAIDS. Ann Intern Med 1995;123(4):241–249. DOI: 10.7326/0003-4819-123-4-199508150-00001

2. Hochberg MC, Roy DA, Kenneth DB, et al. Guidelines for the medical management of osteoarthritis. Part II. Osteoarthritis of the knee. American College of Rheumatology. Arthritis Rheum 1995;38(11):1541–1546. DOI: 10.1002/art.1780381104

3. Smalley WE, Ray WA, Daugherty JR, et al. Nonsteroidal anti-inflammatory drugs and the incidence of hospitalizations for peptic ulcer disease in elderly persons. Am J Epidemiol 1995;141(6):539–545. DOI: 10.1093/oxfordjournals.aje.a117469

4. Setnikar I, Giacchetti C, Zanolo G. Pharmacokinetics of glucosamine in the dog and in man. Arzneimittelforschung 1998;36(4):729–735. PMID: 3718596.

5. Ronca F, Palmieri L, Panicucci P, et al. Anti-inflammatory activity of chondroitin sulfate. Osteoarthritis Cartilage 1998;6(suppl A):14–21. DOI: 10.1016/s1063-4584(98)80006-x

6. McAlindon TE, LaValley MP, Gulin JP, et al. Glucosamine and chondroitin for treatment of osteoarthritis: a systematic quality assessment and meta-analysis. JAMA 2000;283(11):1469–1475. DOI: 10.1001/jama.283.11.1469

7. Tsai K, Chen J, Wen C, et al. Medication adherence among geriatric outpatients prescribed multiple medications. Am J Geriatr Pharmacother 2012;10(1):61–68. DOI: 10.1016/j.amjopharm.2011.11.005

8. Osterberg L, Blaschke T. Adherence to medication. N Eng J Med 2005;353(5):487–497. DOI: 10.1056/NEJMra050100

9. Jin J, Sklar G, Oh V, et al. Factors affecting therapeutic compliance: a review from the patient’s perspective. Therapeut Clin Risk Manag 2008;4(1):269–286. DOI: 10.2147/tcrm.s1458

10. Altman R, Asch E, Bloch D, et al. Development of criteria for the classification and reporting of osteoarthritis. Classification of osteoarthritis of the knee. Diagnostic and Therapeutic Criteria Committee of the American Rheumatism Association. Arthritis Rheum 1986;29(8):1039–1049. DOI: 10.1002/art.1780290816

11. Morisky DE, Green LW, Levine DM. Concurrent and predictive validity of a self-reported measure of medication adherence. Med Care 1986;24(1):67–74. DOI: 10.1097/00005650-198601000-00007

12. Kon E, Filardo G, Drobnic M, et al. Non-surgical management of early knee osteoarthritis. Knee Surg Sports Traumatol Arthrosc 2012;20(3):436–449. DOI: 10.1007/s00167-011-1713-8

13. Pinals RS. Pharmacologic treatment of osteoarthritis. Clin Ther 1992;14(3):336–346.

14. Blenkiron P. The elderly and medication: understanding and compliance in a family practice. Postgrad Med J 1996;72(853):671–676. DOI: 10.1136/pgmj.72.853.671

15. Tiv M, Viel JF, Mauny F, et al. Medication adherence in type 2 diabetes: the ENTRED study 2007, a French population based study. PLoS One 2012;7(3):e32412. DOI: 10.1371/journal.pone.0032412

16. Benner JS, Glynn RJ, Mogun H, et al. Long-term persistence in use of statin therapy in elderly patients. JAMA 2002;288(4):455–461. DOI: 10.1001/jama.288.4.455

17. Okuno J, Yanagi H, Tomura S, et al. Compliance and medication knowledge among elderly Japanese home-care recipients. Eur J Clin Pharmacol 1999;55(2):145–149. DOI: 10.1007/s002280050609

18. Nichols G, Poirier S. Optimizing adherence to pharmaceutical care plans. J Am Pharmaceut Assoc 2000;40(4):475–485. PMID: 10932456.

19. Ho PM, Bryson C, Rumsfeld JS. Medication adherence: its importance in cardiovascular outcomes. Circulation 2009;119(23):3028–3035. DOI:10.1161/CIRCULATIONAHA.108.768986

20. Shams MEE, Barakat EAM. Measuring the rate of therapeutic adherence among outpatients with T2DM in Egypt. Saudi Pharm J 2010;18(4):225–232. DOI: 10.1016/j.jsps.2010.07.004

21. Maclaughlin EJ, Raehl CL, Treadway AK, et al. Assessing medication adherence in the elderly: which tools to use in clinical practice? Drugs Aging 2005;22(3):231–255. DOI: 10.2165/00002512-200522030-00005

22. Ibrahim OH, Jirjees FJ, Mahdi HJ. Barriers affecting compliance of patients with chronic diseases: a preliminary study in United Arab Emirates (UAE) population. Asian J Pharmaceut Clin Res 2011;4(Suppl 2):42–45.

© The Author(s). 2023 Open Access This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (, which permits unrestricted use, distribution, and non-commercial reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver ( applies to the data made available in this article, unless otherwise stated.