Curcumin with turmeric essential oil for knee osteoarthritis

Relation

Shep D, Khanwelkar C, Gade P, Karad S. Safety and efficacy of curcumin compared to diclofenac in knee osteoarthritis: a randomized, open-label, parallel-arm trial. (Link removed). 2019;20(1):214.

Study objective

To evaluate the safety and effectiveness of curcumin compared to diclofenac for pain relief in knee osteoarthritis (OA).

Draft

Prospective, randomized, open-label, parallel, active control clinical trial

Participant

The study included 139 patients aged 38 to 65 years from City Care Accident Hospital, Parli Vaijnath, Maharashtra, India. The participants had suffered from osteoarthritis of the knee joint (confirmed by x-rays) with moderate pain for at least 3 months. There were 70 (45 men, 25 women) patients in the curcumin group and 69 (48 men, 21 women) patients in the diclofenac group.

intervention

Patients received 500 mg of curcumin with turmeric essential oil (BCM-95 Curcumin) or 50 mg of diclofenac (a nonsteroidal anti-inflammatory drug) three times daily. [NSAID]) 2 times per day (BID) for 28 days.

Study parameters assessed

Study parameters were assessed at baseline (Day 0), Week 2 (Day 14), and Week 4 (Day 28). Parameters included Visual Analogue Scale (VAS) for pain, knee injury and Osteoarthritis Outcome Score (KOOS), weight changes, anti-flatulence effect, patient's overall assessment of symptom relief, physician's overall assessment of treatment, and anti-ulcer effect.

Primary outcome measures

The primary outcome was pain perception via change in VAS (0–10, with 10 being worst).

Key insights

Both treatment groups experienced a significant reduction (P<0.05) in pain level.

• Die durchschnittlichen VAS-Werte zu Studienbeginn betrugen 7,84 ± 0,63 (Curcumin) und 7,81 ± 0,73 (Diclofenac).
• Am Tag 14 betrugen die VAS-Scores 4,69 ± 0,79 (Curcumin) und 4,58 ± 0,60 (Diclofenac).
• Am Tag 28 betrugen die VAS-Scores 2,20 ± 0,81 (Curcumin) und 2,20 ± 0,61 (Diclofenac).
• Eine VAS-Reduktion von >50 % wurde bei 66/70 Teilnehmern in der Curcumin-Gruppe und 67/69 Teilnehmern in der Diclofenac-Gruppe erreicht.

A common side effect of NSAIDs is gastrointestinal (GI) disorders. Nineteen participants (28%) in the diclofenac group required a histamine-2 receptor antagonist (H2 blocker) medication to treat stomach problems, while 0% of the curcumin group did. Patients in the curcumin group also experienced significant reductions in bloating and body weight.

Practice implications

Knee OA is a leading cause of disability in the United States and worldwide. The incidence of knee osteoarthritis has more than doubled since the mid-20th century.¹An estimated 30 million adults in the United States are currently affected by OA.²While the development of OA is a multifactorial process, the increasing incidence appears to be influenced by increasing rates of obesity, sedentary lifestyle, comorbidities and longer life expectancy.³

Conventional treatment strategies include pain and inflammation control using NSAIDs, opioids, antidepressants, intra-articular injections, and topical therapies.⁴A recently published study inJAMAshowed that “opioid treatment was not superior to treatment with non-opioid medications for improving pain-related function over 12 months.”⁵The study looked at chronic back pain and OA pain in the hip or knee.

Nonsteroidal anti-inflammatory drugs are among the most commonly used medications and are available over the counter or with a prescription. Diclofenac sodium is only available by prescription in the United States, but some countries offer a lower dosage as an OTC medication. Although NSAIDs are widely used and easily accessible, they have some serious side effects, including ulcers, gastrointestinal bleeding, acute or chronic renal failure, and cardiovascular complications.⁶

Given the 16,500 deaths documented annually from NSAID use, different pain management strategies are clearly needed.

Diclofenac sodium is one of the most commonly used NSAIDs worldwide.⁶Its primary mechanism of action is believed to be inhibition of prostaglandin synthesis via the cyclooxygenase-1 (COX-1) and cyclooxygenase-2 (COX-2) pathways.⁷Prostaglandins play an important role in acute inflammation and its cardinal signals (pain, redness, swelling and heat). However, prostaglandins also have beneficial activity. They protect the mucous membrane, especially in the stomach, by balancing gastric acid secretion and pH. Inhibition of prostaglandin function can lead to ulcer formation and other serious GI side effects.⁸

Consequently, the most common side effects of NSAIDs generally have to do with the GI system. Minor complaints such as dyspepsia, heartburn and nausea are most commonly reported. More serious GI complications may include mucosal destruction leading to ulcers and strictures.⁶Concomitant treatment with other medications used to treat GI effects, such as H2-blockers and proton pump inhibitors, may be necessary when patients are treated with NSAIDs. Nonsteroidal anti-inflammatory agents are also known to increase fluid retention and contribute to cardiovascular side effects. Fluid retention is also a significant factor in weight gain when using this class of medications.⁹

Given the significant risk of side effects from NSAIDs, it is important to explore safe, effective, and natural alternatives to treat OA pain. Curcumin is particularly well suited for this application because it has an exceptional amount of data supporting its use in numerous diseases, including arthritic conditions.

A 2012 clinical trial demonstrated non-inferiority of curcumin (BCM-95) to diclofenac sodium in rheumatoid arthritis.¹⁰The 3-arm study included curcumin monotherapy, diclofenac monotherapy and a combination group. All groups experienced a reduction in Disease Activity Score and American College of Rheumatology criteria. The greatest improvements were observed in the curcumin group, which was statistically significant. Additionally, 14% of the diclofenac sodium group discontinued due to side effects.

There are many ways to improve the relatively poor absorption and bioavailability of curcumin. Using turmeric essential oil has been shown to help maintain serum curcumin levels above 200 ng/g for over 8 hours. Turmeric essential oil also has scientifically proven health benefits. Researchers have identified a key compound in turmeric essential oil called aromatic turmerone (Ar-turmerone), which has its own analgesic properties.¹¹Ar-turmerone has been shown to inhibit COX-2 and matrix metalloproteinase (MMP)-9 by targeting nuclear factor (NF)-κB in vitro (breast cancer and microglial cells).^12,13Ar-turmerone has also been shown to have positive effects on neural stem cell proliferation.¹⁴

Given the 16,500 deaths documented annually from NSAID use, different pain management strategies are clearly needed.^fifteenCurcumin with turmeric essential oil provides a safe and effective solution for OA. Curcumin provides stomach-protective effects, including anti-ulcer properties. A 2016 animal model showed that curcumin protected rats from naproxen-induced ulcers in a dose-dependent manner by increasing free radical scavenging enzymes (superoxide dismutase, catalase, glutathione peroxidase) and preventing lipid peroxidation.¹⁶

restrictions

Limitations of this study include the open-label design, lack of a placebo group, and short duration. A treatment period of 28 days may be insufficient to draw long-term conclusions. A double-blind study with a longer duration and more participants should be considered.

Conclusions

Overall, curcumin with turmeric essential oil (BCM-95 curcumin) at a dose of 500 mg three times daily appears to have a similar efficacy profile to diclofenac sodium 50 mg twice daily for relief of knee pain due to OA. Due to the GI side effects of diclofenac, 28 participants underwent the addition of an H2 blocker, compared to none of the participants in the curcumin group. The curcumin group experienced fewer and less serious side effects (13% in the curcumin group versus 38% in the diclofenac group), demonstrating its superior safety profile. Curcumin with turmeric essential oil may provide a safe and effective alternative for the treatment of knee OA, especially in patients who are particularly vulnerable to the side effects of NSAIDs.

Disclosure of Conflicts of Interest

Cheryl Myers is the Director of Scientific Affairs and Education at EuroMedica, a nutritional supplement and natural health company that owns the exclusive CuraPro and Curaphen product families with BCM-95 Curcumin.