Single dose oral diclofenac for postoperative pain

k-Carrageenan/sericin-based multiparticulate systems: A novel gastro-resistant polymer matrix for indomethacin delivery

This study aimed to develop a natural and multiparticulate carrier of k-carrageenan (k-Car) and sericin (Ser) for encapsulation of indomethacin (IND) in order to minimize gastrointestinal effects caused by immediate-release. Increasing the amount of IND in the formulations subtly reduced the entrapment efficiency (EE) and drug loading (DL) due to matrix saturation. Sericin was essential to improve EE and DL when compared to pure k-Car (EE > 90 % and DL > 47 %) with suitable particle sizes (1.3461 ± 0.1891-1.7213 ± 0.1586 mm). The incorporation and integrity of IND in the particles were confirmed by analytical techniques of HPLC, XRD, FTIR, and SEM. Additionally, the k-Car/Ser matrix was pH-responsive with low IND release at pH 1.2 and extended-release at pH 6.8. The Weibull model had an adequate fit to the experimental data with R²aju 0.950.99 and AIC 82.4-24.9, with curves in parabolic profile (b < 1) and indicative of a controlled drug-release mechanism by diffusion. Besides, k-Car/Ser/IND and placebo were not cytotoxic (cell viability > 85 % at 150-600 μM) for the Caco-2 cell line. Therefore, the polymeric matrix is gastro-resistant, stable, and biocompatible to carry indomethacin and deliver it to the intestinal environment.

Single-dose intravenous diclofenac for acute postoperative pain in adults

BACKGROUND

Postoperative administration of non-steroidal anti-inflammatory drugs (NSAIDs) reduces patient opioid requirements and, in turn, reduces the incidence and severity of opioid-induced adverse events (AEs).

OBJECTIVES

To assess the analgesic efficacy and adverse effects of single-dose intravenous diclofenac, compared with placebo or an active comparator, for moderate to severe postoperative pain in adults.

SEARCH METHODS

We searched the following databases without language restrictions: the Cochrane Central Register of Controlled Trials (Cochrane Register of Studies Online), MEDLINE, and Embase on 22 May 2018. We checked clinical trials registers and reference lists of retrieved articles for additional studies.

SELECTION CRITERIA

We included randomized trials that compared a single postoperative dose of intravenous diclofenac with placebo or another active treatment, for treating acute postoperative pain in adults following any surgery.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane. Two review authors independently considered trials for review inclusion, assessed risk of bias, and extracted data.Our primary outcome was the number of participants in each arm achieving at least 50% pain relief over a four- and six-hour period.Our secondary outcomes were time to, and number of participants using rescue medication; withdrawals due to lack of efficacy, AEs, and for any cause; and number of participants experiencing any AE, serious AEs (SAEs), and NSAID-related AEs. We performed a post hoc analysis of opioid-related AEs, to enable indirect comparisons with other analyses of postoperative analgesics.For subgroup analysis, we planned to analyze different doses and formulations of parenteral diclofenac separately.We assessed the overall quality of the evidence for each outcome using GRADE and created two 'Summary of findings' tables.

MAIN RESULTS

We included eight studies, involving 1756 participants undergoing various surgeries (dental, mixed minor, abdominal, and orthopedic), with 20 to 175 participants receiving intravenous diclofenac in each study. Mean study population ages ranged from 24.5 years to 54.5 years. Intravenous diclofenac doses varied among and within studies, ranging from 3.75 mg to 75 mg. Five studies assessed newer formulations of parenteral diclofenac that could be administered as an undiluted intravenous bolus. Most studies had an unclear risk of bias for several domains and a high risk of bias due to small sample size. The overall quality of evidence for each outcome was generally low for reasons including unclear risk of bias in studies, imprecision, and low event numbers.Primary outcomeThree studies (277 participants) produced a number needed to treat for an additional beneficial outcome (NNTB) for at least 50% of maximum pain relief versus placebo of 2.4 (95% confidence interval (CI) 1.9 to 3.1) over four hours (low-quality evidence). Four studies (436 participants) produced an NNTB of 3.8 versus placebo (95% CI 2.9 to 5.9) over six hours (low-quality evidence). No studies provided data for the comparison of intravenous diclofenac with another NSAID over four hours. At six hours there was no difference between intravenous diclofenac and another NSAID (low-quality evidence).Secondary outcomesFor secondary efficacy outcomes, intravenous diclofenac was generally superior to placebo and similar to other NSAIDs.For time to rescue medication, comparison of intravenous diclofenac versus placebo demonstrated a median of 226 minutes for diclofenac versus 80 minutes for placebo (5 studies, 542 participants, low-quality evidence). There were insufficient data for pooled analysis for comparisons of diclofenac with another NSAID (very low-quality evidence).For the number of participants using rescue medication, two studies (235 participants) compared diclofenac with placebo. The number needed to treat to prevent one additional harmful event (NNTp) (here, the need for rescue medication) compared with placebo was 3.0 (2.2 to 4.5, low-quality evidence). The comparison of diclofenac with another NSAID included only one study (98 participants). The NNTp was 4.5 (2.5 to 33) for ketorolac versus diclofenac (very low-quality evidence).The numbers of participants withdrawing were generally low and inconsistently reported (very low-quality evidence). Participant withdrawals were: 6% (8/140) diclofenac versus 5% (7/128) placebo, and 9% (8/87) diclofenac versus 7% (6/82) another NSAID for lack of efficacy; 2% (4/211) diclofenac versus 0% (0/198) placebo, and 3% (4/138) diclofenac versus 2% (2/129) another NSAID due to AEs; and 11% (21/191) diclofenac versus 17% (30/179) placebo, and 18% (21/118) diclofenac versus 15% (17/111) another NSAID for any cause.Overall adverse event rates were similar between intravenous diclofenac and placebo (71% in both groups, 2 studies, 296 participants) and between intravenous diclofenac and another NSAID (55% and 58%, respectively, 2 studies, 265 participants) (low-quality evidence for both comparisons). Serious and specific AEs were rare, preventing meta-analysis.There were sufficient data for a dose-effect analysis for our primary outcome for only one alternative dose, 18.75 mg. Analysis of the highest dose employed in each study demonstrated a relative benefit compared with placebo of 1.9 (1.4 to 2.4), whereas for the group receiving 18.75 mg, the relative benefit versus placebo was 1.6 (1.2 to 2.1, 2 studies). Compared to another NSAID, the high-dose analysis demonstrated a relative benefit of 0.9 (0.8 to 1.1), for the group receiving 18.75 mg, the relative benefit was 0.78 (0.65 to 0.93). For direct comparison of high dose versus 18.75 mg, the proportion of participants with at least 50% pain relief was 66% (90/137) for the high-dose arm versus 57% (77/135) in the low-dose arm. There were insufficient data for subgroup meta-analysis of different diclofenac formulations.

AUTHORS' CONCLUSIONS

The amount and quality of evidence for the use of intravenous diclofenac as a treatment for postoperative pain is low. The available evidence indicates that postoperative intravenous diclofenac administration offers good pain relief for the majority of patients, but further research may impact this estimate. Adverse events appear to occur at a similar rate to other NSAIDs. Insufficient information is available to assess whether intravenous diclofenac has a different rate of bleeding, renal dysfunction, or cardiovascular events versus other NSAIDs. There was insufficient information to evaluate the efficacy and safety of newer versus traditional formulations of intravenous diclofenac. There was a lack of studies in major and cardiovascular surgeries and in elderly populations, which may be at increased risk for adverse events.

A Review of Chronic Musculoskeletal Pain: Central and Peripheral Effects of Diclofenac

Diclofenac is widely used to manage chronic inflammatory and degenerative joint diseases such as osteoarthritis (OA), rheumatoid arthritis (RA), ankylosing spondylitis, and extra-articular rheumatism. Its various mechanisms of action make it particularly effective in treating nociceptive pain, but it is also an alternative for treating spinal and chronic central pain. Osteoarthritis and rheumatoid arthritis are the most frequently encountered arthritic conditions in adults. The management of nociceptive pain requires a sequential hierarchical approach, with the initial NSAID treatment being characterized by the replacement of one drug with another, or complete discontinuation usually because of insufficient pain control. OA- and RA-related pain is complex and multifactorial, and due to physiological interactions between the signaling of the central and peripheral nervous systems. The mechanisms of action of diclofenac make it particularly effective in treating both nociceptive pain and chronic central pain. This review underlines the mechanisms of diclofenac involved in chronic and acute joint pain, the most relevant adverse events.

Diclofenac Potassium in Acute Postoperative Pain and Dysmenorrhoea: Results from Comprehensive Clinical Trial Reports

We compared the efficacy of diclofenac potassium in unpublished clinical study reports (CSRs) and published reports to examine publication bias, industry bias, and comprehensiveness. Novartis provided CSRs of randomised double-blind trials of diclofenac potassium involving postoperative patients following third molar extraction (3 trials, n=519), gynaecological surgery (3 trials, n=679), and dysmenorrhoea (2 trials, n=711) conducted in 1988–1990. Searches identified published reports of 6 trials. Information from 599/1909 patients was not published; trials with 846/1909 patients were published in a defunct journal. Greater methodological information in CSRs contributed to lesser risk of bias than published trials. Numbers needed to treat (NNT) from CSRs for all six postoperative trials for at least 50% of maximum pain relief over 6 h were 2.2 (95% confidence interval, 1.9–2.6) and 2.1 (1.8–2.4) for 50 and 100 mg diclofenac potassium, respectively. A Cochrane review of published trial data reported NNTs of 2.1 and 1.9, and one comprehensive analysis reported NNTs of 2.2 and 2.1, respectively. All analyses had similar results for patients remedicating within 8 h. No data from dysmenorrhoea CSRs appeared in a Cochrane review. CSRs provide useful information and increase confidence. Stable efficacy estimates with standard study designs reduce the need for updating reviews.

Pharmacokinetics of Diclofenac and Hydroxypropyl-β-Cyclodextrin (HPβCD) Following Administration of Injectable HPβCD-Diclofenac in Subjects With Mild to Moderate Renal Insufficiency or Mild Hepatic Impairment

Given their established analgesic properties, nonsteroidal anti‐inflammatory drugs (NSAIDs) represent an important postoperative pain management option. This study investigated: (1) the effects of mild or moderate renal insufficiency and mild hepatic impairment on the pharmacokinetics (PK) of diclofenac and hydroxypropyl‐β‐cyclodextrin (HPβCD) following administration of the injectable NSAID HPβCD‐diclofenac; and (2) the PK of HPβCD following administration of HPβCD‐diclofenac and intravenous itraconazole formulated with HPβCD in healthy adults. Diclofenac clearance (CL) and volume of distribution (V_z) tended to increase with decreasing renal function (moderate insufficiency versus mild insufficiency or healthy controls). Regression analysis demonstrated a significant relationship between V_z (but not CL or elimination half‐life, t_½) and renal function. HPβCD CL was significantly decreased in subjects with renal insufficiency, with a corresponding increase in t_½. There were no significant differences in diclofenac or HPβCD PK in subjects with mild hepatic impairment versus healthy subjects. Exposure to HPβCD in healthy subjects following HPβCD‐diclofenac administration was ∼12% of that with intravenous itraconazole, after adjusting for dosing schedule and predicted accumulation (<5% without adjustment). With respect to PK properties, these results suggest that HPβCD‐diclofenac might be administered to patients with mild or moderate renal insufficiency or mild hepatic impairment without dose adjustment (NCT00805090).

Cardiovascular and cerebrovascular risk with nonsteroidal anti-inflammatory drugs and cyclooxygenase 2 inhibitors: latest evidence and clinical implications

Observational studies and meta-analyses have shown that the administration of nonsteroidal anti-inflammatory drugs (NSAIDs), especially when prescribed at high doses for long periods of time, can potentially increase the risk of cardiovascular diseases. The increased thrombotic risk related to the use of NSAIDs is mainly due to their cyclooxygenase 2 selectivity. The dosage use, the formulation selected and the duration of the therapy are other factors that can significantly impact on the cardiovascular risk. In order to minimize the risk, prescription of the right drug based on the patient's features and the different safety profiles of several NSAIDs that are available on the market is key for their appropriate administration. Despite the baseline cardiovascular and gastrointestinal risk of each patient, monitoring of patients is suggested for increases in blood pressure, development of edema, deterioration of renal function, or gastrointestinal bleeding during long-term treatment with NSAIDs.

Single dose intravenous diclofenac for acute postoperative pain in adults

This is a protocol for a Cochrane Review (Intervention). The objectives are as follows:

To assess the analgesic efficacy and adverse effects of a single dose of intravenous diclofenac, compared with placebo or an active comparator, for moderate to severe postoperative pain in adults.

Single dose oral diclofenac for acute postoperative pain in adults

BACKGROUND

Diclofenac is a nonsteroidal anti-inflammatory drug, available as a potassium salt (immediate release) or sodium salt (enteric coated to suppress dissolution in the stomach). This review updates an earlier review published in the Cochrane Database of Systematic Reviews (Issue 2, 2009) entitled 'Single dose oral diclofenac for acute postoperative pain in adults'.

OBJECTIVES

To assess the analgesic efficacy and adverse effects of a single oral dose of diclofenac for moderate to severe postoperative pain, using methods that permit comparison with other analgesics evaluated in standardised trials using almost identical methods and outcomes.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, the Oxford Pain Relief Database, two clinical trial registries, and the reference lists of articles. The date of the most recent search was 9 March 2015.

SELECTION CRITERIA

Randomised, double-blind, placebo-controlled clinical trials of single dose, oral diclofenac (sodium or potassium) for acute postoperative pain in adults.

DATA COLLECTION AND ANALYSIS

Two review authors independently considered studies for inclusion in the review, assessed risk of bias, and extracted data. We used the area under the pain relief versus time curve to derive the proportion of participants with at least 50% pain relief over six hours prescribed either diclofenac or placebo. We calculated the risk ratio (RR) and number needed to treat to benefit (NNT). We used information on the use of rescue medication to calculate the proportion of participants requiring rescue medication and the weighted mean of the median time to use. We also collected information on adverse effects.

MAIN RESULTS

This update included three new studies, providing a 26% increase in participants in comparisons between diclofenac and placebo. We included 18 studies involving 3714 participants, 1902 treated with diclofenac and 1007 with placebo. This update has also changed the focus of the review, examining the effects of formulation in more detail than previously. This is a result of increased understanding of the importance of speed of onset in determining analgesic efficacy in acute pain.The largest body of information, for diclofenac potassium 50 mg, in seven studies, produced an NNT for at least 50% of maximum pain relief compared with placebo of 2.1 (95% confidence interval (CI) 1.9 to 2.5) (high quality evidence). There was a graded improvement in efficacy as doses rose from 25 mg to 100 mg, both for participants achieving at least 50% maximum pain relief, and for remedication within 6 to 8 hours. Fast-acting formulations (dispersible products, solutions, and softgel formulations) had a similar efficacy for a 50 mg dose, with an NNT of 2.4 (2.0 to 3.0). Diclofenac sodium in a small number of studies produced a lesser effect, with an NNT of 6.6 (4.1 to 17) for the 50 mg dose.Adverse event rates were low in these single dose studies, with no difference between diclofenac and placebo (moderate quality evidence).

AUTHORS' CONCLUSIONS

Diclofenac potassium provides good pain relief at 25 mg, 50 mg, and 100 mg doses. Diclofenac sodium has limited efficacy and should probably not be used in acute pain.

WITHDRAWN: Diclofenac for acute pain in children

At December 2014, this review has been withdrawn from the Cochrane Library. This review is out of date, although it is correct at the date of publication. The review may be misleading as new studies could alter the original conclusions. All previous versions of the review can be found in the ‘Other versions’ tab. We are seeking additional authors to support the updating of this review. For further information, please contact PaPaS Managing Editor, Anna Hobson [Contact Person].

The editorial group responsible for this previously published document have withdrawn it from publication.

Diclofenac sodium injection (akis(®), dicloin (®)): a review of its use in the management of pain

A novel formulation of diclofenac sodium suitable for subcutaneous or intramuscular injection (Akis(®), Dicloin(®)) has been developed using the complexing agent hydroxypropyl-β-cyclodextrin (HPβCD) as a solubility enhancer. Diclofenac HPβCD is available in several European countries, where it is indicated for use in adults with acute forms of pain, including postoperative pain. Clinical trials have demonstrated the analgesic efficacy of diclofenac HPβCD in terms of relieving moderate to severe postoperative pain in patients undergoing dental surgery or minor orthopaedic surgery. Subcutaneous diclofenac HPβCD also effectively relieved moderate to severe neuropathic pain, related to cancer or not. Diclofenac HPβCD was generally well tolerated in clinical trials, with injection-site reactions among the most commonly reported adverse events. The local tolerability of diclofenac HPβCD was consistently rated as 'good' or 'excellent' across all studies. Subcutaneous administration of diclofenac is a valid alternative to intramuscular delivery, with the advantages of easier administration, the availability of additional body sites suitable for injection and the potential for self-administration. Thus, diclofenac HPβCD 25, 50 or 75 mg/mL solution for subcutaneous or intramuscular injection extends the treatment options available for use in the management of pain in adults.

Patient controlled analgesia with remifentanil versus epidural analgesia in labour: randomised multicentre equivalence trial

OBJECTIVE

To determine women's satisfaction with pain relief using patient controlled analgesia with remifentanil compared with epidural analgesia during labour.

DESIGN

Multicentre randomised controlled equivalence trial.

SETTING

15 hospitals in the Netherlands.

PARTICIPANTS

Women with an intermediate to high obstetric risk with an intention to deliver vaginally. To exclude a clinically relevant difference in satisfaction with pain relief of more than 10%, we needed to include 1136 women. Because of missing values for satisfaction this number was increased to 1400 before any analysis. We used multiple imputation to correct for missing data.

INTERVENTION

Before the onset of active labour consenting women were randomised to a pain relief strategy with patient controlled remifentanil or epidural analgesia if they requested pain relief during labour.

MAIN OUTCOME MEASURES

Primary outcome was satisfaction with pain relief, measured hourly on a visual analogue scale and expressed as area under the curve (AUC), thus providing a time weighted measure of total satisfaction with pain relief. A higher AUC represents higher satisfaction with pain relief. Secondary outcomes were pain intensity scores, mode of delivery, and maternal and neonatal outcomes. Analysis was done by intention to treat. The study was defined as an equivalence study for the primary outcome.

RESULTS

1414 women were randomised, of whom 709 were allocated to patient controlled remifentanil and 705 to epidural analgesia. Baseline characteristics were comparable. Pain relief was ultimately used in 65% (447/687) in the remifentanil group and 52% (347/671) in the epidural analgesia group (relative risk 1.32, 95% confidence interval 1.18 to 1.48). Cross over occurred in 7% (45/687) and 8% (51/671) of women, respectively. Of women primarily treated with remifentanil, 13% (53/402) converted to epidural analgesia, while in women primarily treated with epidural analgesia 1% (3/296) converted to remifentanil. The area under the curve for total satisfaction with pain relief was 30.9 in the remifentanil group versus 33.7 in the epidural analgesia group (mean difference -2.8, 95% confidence interval -6.9 to 1.3). For who actually received pain relief the area under the curve for satisfaction with pain relief after the start of pain relief was 25.6 in the remifentanil group versus 36.1 in the epidural analgesia group (mean difference -10.4, -13.9 to -7.0). The rate of caesarean section was 15% in both groups. Oxygen saturation was significantly lower (SpO2 <92%) in women who used remifentanil (relative risk 1.5, 1.4 to 1.7). Maternal and neonatal outcomes were comparable between both groups.

CONCLUSION

In women in labour, patient controlled analgesia with remifentanil is not equivalent to epidural analgesia with respect to scores on satisfaction with pain relief. Satisfaction with pain relief was significantly higher in women who were allocated to and received epidural analgesia.

TRIAL REGISTRATION

Netherlands Trial Register NTR2551.

Single dose oral etoricoxib for acute postoperative pain in adults

BACKGROUND

This is an updated version of the original Cochrane review first published in Issue 2, 2009, and updated in Issue 4, 2012.Etoricoxib is a selective cyclo-oxygenase-2 (COX-2) inhibitor licensed for the relief of chronic pain in osteoarthritis and rheumatoid arthritis, and acute pain in some jurisdictions. This class of drugs is believed to be associated with fewer upper gastrointestinal adverse effects than conventional non-steroidal anti-inflammatory drugs (NSAIDs).

OBJECTIVES

To assess the efficacy and adverse effects of single dose etoricoxib for acute postoperative pain using methods that permit accurate comparison with other analgesics evaluated in the same way, using criteria of efficacy recommended by in-depth studies at the individual patient level.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, the Oxford Pain Database, www.clinicaltrials.gov, and reference lists of articles. The date of the most recent search was 31 January 2014.

SELECTION CRITERIA

Randomised, double-blind, placebo-controlled clinical trials of single dose, oral etoricoxib for acute postoperative pain in adults.

DATA COLLECTION AND ANALYSIS

Two review authors independently considered studies for inclusion in the review, assessed quality, and extracted data. We used the area under the pain relief versus time curve to derive the proportion of participants prescribed etoricoxib or placebo with at least 50% pain relief over six hours, using validated equations. We calculated relative risk (RR) and number needed to treat to benefit (NNT). We used information on use of rescue medication to calculate the proportion of participants requiring rescue medication and the weighted mean of the median time to use. We also collected information on adverse events.

MAIN RESULTS

We identified no new studies for this updated review, which includes six studies with 1214 participants in comparisons of etoricoxib with placebo. All six studies reported on the 120 mg dose (798 participants in a comparison with placebo). Sixty-six per cent of participants with etoricoxib 120 mg and 12% with placebo reported at least 50% pain relief (NNT 1.8 (1.7 to 2.0); high-quality evidence). For dental studies only, the NNT was 1.6 (1.5 to 1.8). A single dose of 90 mg produced similar results in one large trial. Other doses (60, 180, and 240 mg) were each studied in only one treatment arm.Significantly fewer participants used rescue medication over 24 hours when taking etoricoxib 120 mg than placebo (NNT to prevent remedication 2.2 (1.9 to 2.8)), and the median time to use of rescue medication was 20 hours for etoricoxib and two hours for placebo. Adverse events were reported at a similar rate to placebo (moderate-quality evidence), with no serious events.

AUTHORS' CONCLUSIONS

Single-dose oral etoricoxib produces high levels of good quality pain relief after surgery, and adverse events did not differ from placebo in these studies. The 120 mg dose is as effective as, or better than, other commonly used analgesics.

Effects of intravenous diclofenac on postoperative sore throat in patients undergoing laparoscopic surgery at Aga Khan University Hospital, Nairobi: a prospective, randomized, double blind controlled trial

BACKGROUND

postoperative sore throat is the commonest complication after endotracheal intubation. The efficacy of intravenous non-steroidal anti-inflammatory drugs in alleviating postoperative sore throat has not been investigated.

OBJECTIVE

To evaluate the effect of intravenous diclofenac sodium on the occurrence and severity of postoperative sore throat.

METHODS

42 in-patients scheduled for laparoscopic surgery were randomized into two equal groups to receive either a single dose of 75mg intravenous diclofenac sodium in addition to standard treatment taken at our hospital for the prevention of postoperative sore throat or to receive standard treatment only. All patients were interviewed postoperatively at 2, 6 and 18 hours. Data of the baseline characteristics, the incidence and severity of sore throat were collected. If sore throat was present, a Visual Analogue Score was used to assess its severity.

RESULTS

the baseline characteristics of the participants were similar. The majority of the patients undergoing laparoscopic surgery were women. There was no statistically significant difference in the occurrence or severity of postoperative sore throat between the diclofenac and standard treatment groups at 2, 6 and 18 hours postoperatively.

CONCLUSION

Intravenous diclofenac sodium does not reduce the occurrence or severity of postoperative sore throat.

Pre-operative assessment and post-operative care in elective shoulder surgery

Pre-operative assessment is required prior to the majority of elective surgical procedures, primarily to ensure that the patient is fit to undergo surgery, whilst identifying issues that may need to be dealt with by the surgical or anaesthetic teams. The post-operative management of elective surgical patients begins during the peri-operative period and involves several health professionals. Appropriate monitoring and repeated clinical assessments are required in order for the signs of surgical complications to be recognised swiftly and adequately. This article examines the literature regarding pre-operative assessment in elective orthopaedic surgery and shoulder surgery, whilst also reviewing the essentials of peri- and post-operative care. The need to recognise common post-operative complications early and promptly is also evaluated, along with discussing thromboprophylaxis and post-operative analgesia following shoulder surgery.

Effects of paracetamol, non-steroidal anti-inflammatory drugs, acetylsalicylic acid, and opioids on bone mineral density and risk of fracture: results of the Danish Osteoporosis Prevention Study (DOPS)

Pain medication has been associated with fractures. We found higher weight in paracetamol and non-steroidal anti-inflammatory drugs (NSAID) users and lower vitamin D levels in opioid and acetylsalicylic acid users. None of the pain medications influenced bone mineral density or loss. NSAID were associated with an increased fracture risk.

INTRODUCTION

To study the effects of use of paracetamol, non-steroidal anti-inflammatory drugs (NSAID), acetylsalicylic acid (ASA), and opioids on bone mineral density (BMD) and risk of fractures.

METHODS

Two-thousand sixteen perimenopausal women followed for 10 years as part of a partly randomised comprehensive cohort study on hormone therapy (HT). BMD was measured at baseline and after 10 years by DXA (Hologic).

RESULTS

Paracetamol users were heavier (70.4 ± 13.4 vs. 67.7 ± 11.9 kg, 2p < 0.01) than non-users. NSAID users were heavier (71.6 ± 15.6 vs. 67.8 ± 11.9 kg, 2p = 0.04) than non-users. ASA users had lower 25-hydroxy-vitamin D (25OHD) levels (21.9 ± 9.3 vs. 25.3 ± 12.4 ng/ml, 2p < 0.01) than non-users. Opioid users had lower 25OHD (21.4 ± 8.4 vs. 25.2 ± 12.3 ng/ml) and lower intake of vitamin D (2.2 ± 1.1 vs. 3.1 ± 3.0 μg/day, 2p < 0.01) than non-users. Despite these differences, no baseline differences were present in spine, hip, forearm or whole body BMD. Over 10 years, no differences were present in BMD alterations except a small trend towards a higher BMD gain in the spine in users of paracetamol, NSAID, ASA, and opioids compared to non-exposed. After adjustment, NSAID exposed sustained more fractures (HR = 1.44, 95% CI 1.07-1.93) than non-users. For users of paracetamol and opioids, a non-significant trend towards more fractures was present after adjustment. For ASA users, no excess risk of fractures was present.

CONCLUSION

Significant differences exist between subjects exposed to pain medications and non-users. Despite an absence of an effect over time on BMD, users of NSAID experienced more fractures than expected. The reasons for this have to be explored in further studies.

Single dose oral analgesics for acute postoperative pain in adults

BACKGROUND

Thirty-five Cochrane Reviews of randomised trials testing the analgesic efficacy of individual drug interventions in acute postoperative pain have been published. This overview brings together the results of all those reviews and assesses the reliability of available data.

OBJECTIVES

To summarise data from all Cochrane Reviews that have assessed the effects of pharmaceutical interventions for acute pain in adults with at least moderate pain following surgery, who have been given a single dose of oral analgesic taken alone.

METHODS

We identified systematic reviews in The Cochrane Library through a simple search strategy. All reviews were overseen by a single Review Group, had a standard title, and had as their primary outcome numbers of participants with at least 50% pain relief over four to six hours compared with placebo. For individual reviews we extracted the number needed to treat (NNT) for this outcome for each drug/dose combination, and also the percentage of participants achieving at least 50% maximum pain relief, the mean of mean or median time to remedication, the percentage of participants remedicating by 6, 8, 12, or 24 hours, and results for participants experiencing at least one adverse event.

MAIN RESULTS

The overview included 35 separate Cochrane Reviews with 38 analyses of single dose oral analgesics tested in acute postoperative pain models, with results from about 45,000 participants studied in approximately 350 individual studies. The individual reviews included only high-quality trials of standardised design and outcome reporting. The reviews used standardised methods and reporting for both efficacy and harm. Event rates with placebo were consistent in larger data sets. No statistical comparison was undertaken.There were reviews but no trial data were available for acemetacin, meloxicam, nabumetone, nefopam, sulindac, tenoxicam, and tiaprofenic acid. Inadequate amounts of data were available for dexibuprofen, dextropropoxyphene 130 mg, diflunisal 125 mg, etoricoxib 60 mg, fenbufen, and indometacin. Where there was adequate information for drug/dose combinations (at least 200 participants, in at least two studies), we defined the addition of four comparisons of typical size (400 participants in total) with zero effect as making the result potentially subject to publication bias and therefore unreliable. Reliable results were obtained for 46 drug/dose combinations in all painful postsurgical conditions; 45 in dental pain and 14 in other painful conditions.NNTs varied from about 1.5 to 20 for at least 50% maximum pain relief over four to six hours compared with placebo. The proportion of participants achieving this level of benefit varied from about 30% to over 70%, and the time to remedication varied from two hours (placebo) to over 20 hours in the same pain condition. Participants reporting at least one adverse event were few and generally no different between active drug and placebo, with a few exceptions, principally for aspirin and opioids.Drug/dose combinations with good (low) NNTs were ibuprofen 400 mg (2.5; 95% confidence interval (CI) 2.4 to 2.6), diclofenac 50 mg (2.7; 95% CI 2.4 to 3.0), etoricoxib 120 mg (1.9; 95% CI 1.7 to 2.1), codeine 60 mg + paracetamol 1000 mg (2.2; 95% CI 1.8 to 2.9), celecoxib 400 mg (2.5; 95% CI 2.2 to 2.9), and naproxen 500/550 mg (2.7; 95% CI 2.3 to 3.3). Long duration of action (≥ 8 hours) was found for etoricoxib 120 mg, diflunisal 500 mg, oxycodone 10 mg + paracetamol 650 mg, naproxen 500/550 mg, and celecoxib 400 mg.Not all participants had good pain relief and for many drug/dose combinations 50% or more did not achieve at last 50% maximum pain relief over four to six hours.

AUTHORS' CONCLUSIONS

There is a wealth of reliable evidence on the analgesic efficacy of single dose oral analgesics. There is also important information on drugs for which there are no data, inadequate data, or where results are unreliable due to susceptibility to publication bias. This should inform choices by professionals and consumers.

Dealing with substantial heterogeneity in Cochrane reviews. Cross-sectional study

BACKGROUND

Dealing with heterogeneity in meta-analyses is often tricky, and there is only limited advice for authors on what to do. We investigated how authors addressed different degrees of heterogeneity, in particular whether they used a fixed effect model, which assumes that all the included studies are estimating the same true effect, or a random effects model where this is not assumed.

METHODS

We sampled randomly 60 Cochrane reviews from 2008, which presented a result in its first meta-analysis with substantial heterogeneity (I2 greater than 50%, i.e. more than 50% of the variation is due to heterogeneity rather than chance). We extracted information on choice of statistical model, how the authors had handled the heterogeneity, and assessed the methodological quality of the reviews in relation to this.

RESULTS

The distribution of heterogeneity was rather uniform in the whole I2 interval, 50-100%. A fixed effect model was used in 33 reviews (55%), but there was no correlation between I2 and choice of model (P = 0.79). We considered that 20 reviews (33%), 16 of which had used a fixed effect model, had major problems. The most common problems were: use of a fixed effect model and lack of rationale for choice of that model, lack of comment on even severe heterogeneity and of reservations and explanations of its likely causes. The problematic reviews had significantly fewer included trials than other reviews (4.3 vs. 8.0, P = 0.024). The problems became less pronounced with time, as those reviews that were most recently updated more often used a random effects model.

CONCLUSION

One-third of Cochrane reviews with substantial heterogeneity had major problems in relation to their handling of heterogeneity. More attention is needed to this issue, as the problems we identified can be essential for the conclusions of the reviews.

Single dose oral gabapentin for established acute postoperative pain in adults

BACKGROUND

Gabapentin is an antiepileptic drug, also used in the treatment of neuropathic pain, which is the subject of a Cochrane review, currently under revision. Its efficacy in treating established acute postoperative pain has not been demonstrated.

OBJECTIVES

To assess the efficacy and safety of single dose oral gabapentin compared with placebo in established acute postoperative pain using methods that permit comparison with other analgesics.

SEARCH STRATEGY

We searched Cochrane CENTRAL, MEDLINE, EMBASE, and the Oxford Pain Relief Database. Additional studies were sought from reference lists of retrieved articles and reviews. Clinical trials databases were searched for unpublished studies; clinical trial reports of several unpublished studies have been made public following litigation in the US.

SELECTION CRITERIA

Single oral dose, randomised, double-blind, placebo-controlled trials of gabapentin for relief of established moderate to severe postoperative pain in adults.

DATA COLLECTION AND ANALYSIS

Studies were assessed for methodological quality and data extracted by two review authors independently. Numbers of participants with at least 50% of maximum possible total pain relief (TOTPAR) or summed pain intensity difference (SPID) with gabapentin or placebo were calculated and used to derive relative benefit (RB) or risk (RR), and number-needed-to-treat-to-benefit (NNT). Numbers of participants using rescue medication, and time to its use, were sought as additional measures of efficacy. Information on adverse events and withdrawals was collected.

MAIN RESULTS

Four unpublished studies met inclusion criteria; in three, participants had pain following dental surgery, and one followed major orthopaedic surgery; 177 participants were treated with a single dose of gabapentin 250 mg, 21 with gabapentin 500 mg, and 172 with placebo. At least 50% pain relief over 6 hours was achieved by 15% with gabapentin 250 mg and 5% with placebo; giving a RB of 2.5 (95% CI 1.2 to 5.0) and an NNT of 11 (6.4 to 35). Significantly fewer participants needed rescue medication within 6 hours with gabapentin 250 mg than with placebo; NNT to prevent use 5.8. About one third of participants reported adverse events with both gabapentin 250 mg and placebo. No serious adverse events occurred with gabapentin.

AUTHORS' CONCLUSIONS

Gabapentin 250 mg is statistically superior to placebo in the treatment of established acute postoperative pain, but the NNT of 11 for at least 50% pain relief over 6 hours with gabapentin 250 mg is of limited clinical value and inferior to commonly used analgesics. Gabapentin 250 mg is not clinically useful as a stand-alone analgesic in established acute postoperative pain, though this is probably the first demonstration of analgesic effect of an antiepileptic in established acute pain.

Single dose oral fenbufen for acute postoperative pain in adults

BACKGROUND

Fenbufen is a non-selective non-steroidal anti-inflammatory drug (NSAID), used to treat acute and chronic painful conditions. There is no known systematic review of its use in acute postoperative pain.

OBJECTIVES

To assess efficacy, duration of action, and associated adverse events of single dose oral fenbufen in acute postoperative pain in adults.

SEARCH STRATEGY

We searched Cochrane CENTRAL, MEDLINE, EMBASE and the Oxford Pain Relief database for studies to June 2009.

SELECTION CRITERIA

Randomised, double blind, placebo-controlled trials of single dose orally administered fenbufen in adults with moderate to severe acute postoperative pain.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trial quality and extracted data. Pain relief or pain intensity data were extracted and converted into the dichotomous outcome of number of participants with at least 50% pain relief over 4 to 6 hours, from which relative risk and number needed to treat to benefit (NNT) were calculated. Numbers of participants using rescue medication over specified time periods, and time to use of rescue medication, were sought as additional measures of efficacy. Information on adverse events and withdrawals were collected.

MAIN RESULTS

Searches identified only one study with (90 participants in total, 31 taking fenbufen). The study compared oral fenbufen 800 mg, fenbufen 400 mg, and placebo in participants with established postoperative pain. Fenbufen at both doses had apparent analgesic efficacy, but the numbers of participants was too small to allow sensible analysis. Gastrointestinal adverse events were noted in 4 of 15 participants taking fenbufen 800 mg.

AUTHORS' CONCLUSIONS

In the absence of evidence of efficacy for oral fenbufen in acute postoperative pain, its use in this indication is not justified at present. Because trials clearly demonstrating analgesic efficacy in the most basic of acute pain studies is lacking, use in other indications should be evaluated carefully. Given the large number of available drugs of this and similar classes which are effective, there is no urgent research agenda for this particular drug.

Single dose oral sulindac for acute postoperative pain in adults

BACKGROUND

Sulindac is a non-steroidal anti-inflammatory drug (NSAID) licensed for use in rheumatic disease and other musculoskeletal disorders in the UK, and widely available in other countries worldwide. This review sought to evaluate the efficacy and safety of oral sulindac in acute postoperative pain, using clinical studies of patients with established pain, and with outcomes measured primarily over 6 hours using standard methods. This type of study has been used for many decades to establish that drugs have analgesic properties.

OBJECTIVES

To assess the efficacy of single dose oral sulindac in acute postoperative pain, and any associated adverse events.

SEARCH STRATEGY

We searched Cochrane CENTRAL, MEDLINE, EMBASE and the Oxford Pain Relief Database for studies up to June 2009.

SELECTION CRITERIA

Randomised, double-blind, placebo-controlled clinical trials of oral sulindac for relief of acute postoperative pain in adults.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trial quality and extracted data. We planned to use area under the "pain relief versus time" curve to derive the proportion of participants with meloxicam experiencing least 50% pain relief over 4 to 6 hours, using validated equations; to use number needed to treat to benefit (NNT); the proportion of participants using rescue analgesia over a specified time period; time to use of rescue analgesia; information on adverse events and withdrawals.

MAIN RESULTS

No studies were identified by the searches that examined oral sulindac in patients with established postoperative pain.

AUTHORS' CONCLUSIONS

In the absence of evidence of efficacy, at present, for oral sulindac in acute postoperative pain, its use in this indication is not justified. Because trials clearly demonstrating analgesic efficacy in the most basic of acute pain studies is lacking, use in other indications should be evaluated carefully. Given the large number of available drugs of this and similar classes, there is no urgent research agenda.

Single dose oral aceclofenac for postoperative pain in adults

BACKGROUND

Aceclofenac is the prodrug of the non-steroidal anti-inflammatory drug (NSAID) diclofenac, widely used to treat acute and chronic pain. There are no known systematic reviews of its analgesic efficacy in acute postoperative pain. This review sought to evaluate the efficacy and safety of oral aceclofenac in acute postoperative pain, using clinical studies of patients with established pain, and with outcomes measured primarily over 6 hours using standard methods. This type of study has been used for many decades to establish that drugs have analgesic properties.

OBJECTIVES

To assess the efficacy of single dose oral aceclofenac in acute postoperative pain, and any associated adverse events.

SEARCH STRATEGY

We searched The Cochrane Library (Issue 1, 2009), MEDLINE via Ovid (1966 to March 2009); EMBASE via Ovid (1980 to March 2009); the Oxford Pain Relief Database (1950 to 1994); and reference lists of articles.

SELECTION CRITERIA

Randomised, double-blind, placebo-controlled clinical trials of oral aceclofenac for relief of acute postoperative pain in adults.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trial quality and extracted data. The area under the "pain relief versus time" curve was used to derive the proportion of participants with paracetamol plus codeine and placebo or paracetamol alone experiencing least 50% pain relief over 4 to 6 hours, using validated equations. The number needed to treat to benefit (NNT) was calculated using 95% confidence intervals (CI). The proportion of participants using rescue analgesia over a specified time period, and time to use of rescue analgesia, were sought as additional measures of efficacy. Information on adverse events and withdrawals was also collected.

MAIN RESULTS

Searches identified only one study (217 participants total), which used oral aceclofenac 150 mg in patients with established postoperative pain. Aceclofenac 150 mg could not be distinguished from placebo, though ibuprofen 400 mg was distinguished from placebo.

AUTHORS' CONCLUSIONS

In the absence of evidence of efficacy for oral aceclofenac in acute postoperative pain (at least at 150 mg single dose), its use in this indication is not justified. Because trials clearly demonstrating analgesic efficacy in the most basic of acute pain studies are lacking, use in other indications should be evaluated carefully. Given the large number of effective drugs available in this and similar classes of analgesics, there is no urgent research agenda required to demonstrate the effective dose of aceclofenac in acute postoperative pain.

Intravenous or intramuscular parecoxib for acute postoperative pain in adults

BACKGROUND

Parecoxib was the first COX-2 available for parenteral administration, and may, given intravenously or intramuscularly, offer advantages over oral medication when patients have nausea and vomiting or are unable to swallow, such as in the immediate postoperative period.

OBJECTIVES

Assess the efficacy of single dose intravenous or intramuscular parecoxib in acute postoperative pain, the requirement for rescue medication, and any associated adverse events.

SEARCH STRATEGY

We searched Cochrane CENTRAL, MEDLINE, EMBASE in November 2008.

SELECTION CRITERIA

Randomised, double-blind, placebo-controlled clinical trials of parecoxib compared with placebo for relief of acute postoperative pain in adults.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trial quality and extracted data. The area under the "pain relief versus time" curve was used to derive the proportion of participants with parecoxib and placebo experiencing at least 50% pain relief over 6 hours, using validated equations. The number-needed-to-treat-to-benefit (NNT) was calculated using 95% confidence intervals (CI). The proportion of participants using rescue analgesia over a specified time period, and time to use of rescue analgesia, were sought as additional measures of efficacy. Information on adverse events and withdrawals were also collected.

MAIN RESULTS

Seven studies (1446 participants) were included. There was no significant difference between doses, or between intravenous and intramuscular administration for 50% pain relief over 6 hours: NNTs compared with placebo were 3.1 (2.4 to 4.5), 2.4 (2.1 to 2.8), and 1.8 (1.5 to 2.3) for 10, 20, and 40 mg parecoxib respectively. Fewer participants required rescue medication over 24 hours with parecoxib than placebo: parecoxib 40 mg was significantly better than parecoxib 20 mg (NNTs to prevent use of rescue medication 7.5 (5.3 to 12.8) and 3.3 (2.6 to 4.5) respectively; P < 0.0007). Median time to use of rescue medication was 3.1 hours, 6.9 hours and 10.6 hours with parecoxib 10 mg, 20 mg and 40 mg respectively, and 1.5 hours with placebo. Adverse events were generally mild to moderate, rarely led to withdrawal, and did not differ in frequency between groups. No serious adverse events were reported with parecoxib or placebo.

AUTHORS' CONCLUSIONS

A single dose of parecoxib 20 mg or 40 mg provided effective analgesia for 50 to 60% of those treated compared to about 15% with placebo, and was well tolerated. Duration of analgesia was longer, and significantly fewer participants required rescue medication over 24 hours with the higher dose.

Single dose oral diclofenac for acute postoperative pain in adults

BACKGROUND

Diclofenac is a non-steroidal anti-inflammatory drug (NSAID), available as a potassium salt (immediate-release) or sodium salt (delayed-release). This review updates an earlier review published in The Cochrane Database of Systematic Reviews (Issue 2, 2004) on 'Single dose oral diclofenac for postoperative pain'.

OBJECTIVES

To assess single dose oral diclofenac for the treatment of acute postoperative pain.

SEARCH STRATEGY

Cochrane CENTRAL, MEDLINE, EMBASE, Biological Abstracts, the Oxford Pain Relief Database, and reference lists of articles were searched; last search December 2008.

SELECTION CRITERIA

Randomised, double-blind, placebo-controlled clinical trials of single dose, oral diclofenac (sodium or potassium) for acute postoperative pain in adults.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed studies for inclusion and quality, and extracted data. The area under the pain relief versus time curve was used to derive the proportion of participants with at least 50% pain relief over 4 to 6 hours, using validated equations. Relative benefit (risk) and number needed to treat to benefit (NNT) were calculated. Information on adverse events, time to remedication, and participants needing additional analgesia was also collected.

MAIN RESULTS

Fifteen studies (eight additional studies) with 1512 participants more than doubled the information available at each dose. Overall 50% to 60% of participants experienced at least 50% pain relief over 4 to 6 hours at any dose with diclofenac, compared to 10 to 20% with placebo, giving NNTs of about 2.5 for doses of 25 mg to 100 mg (similar to earlier review); no dose response was demonstrated. At 50 mg and 100 mg, NNTs for diclofenac potassium (2.1 (1.8 to 2.4) and 1.9 (1.7 to 2.2)) were significantly lower (better) than for diclofenac sodium (6.7 (4.2 to 17) and 4.5 (3.2 to 7.7)). The median time to use of rescue medication was 2 hours for placebo, 4.3 hours for diclofenac 50 mg and 4.9 hours for diclofenac 100 mg. Adverse events were reported at a similar rate to placebo, with no serious events.

AUTHORS' CONCLUSIONS

Oral diclofenac is an effective single-dose treatment for moderate to severe postoperative pain. Significantly more participants experienced at least 50% pain relief over 4 to 6 hours with diclofenac potassium than with diclofenac sodium. There was no significant difference between diclofenac and placebo in the incidence of adverse events.

Diclofenac sodium injection (Dyloject): in postoperative pain

*A new formulation of the nonselective NSAID diclofenac sodium suitable for intravenous bolus injection has been developed using hydroxypropyl beta-cyclodextrin as a solubility enhancer (HPbetaCD diclofenac). * HPbetaCD diclofenac intravenous bolus injection was shown to be bioequivalent to the existing parenteral formulation of diclofenac containing propylene glycol and benzyl alcohol as solubilizers (PG-BA diclofenac), which is relatively insoluble and requires slow intravenous infusion over 30 minutes. * Single-dose HPbetaCD diclofenac 3.75, 9.4, 18.75, 25, 37.5, 50 and 75 mg administered by intravenous bolus injection produced significantly greater responses than placebo for total pain relief (TOTPAR) over 6 hours or pain intensity at 4 hours in the treatment of moderate or severe postoperative dental pain in randomized, double-blind trials. HPbetaCD diclofenac 37.5 and 75 mg were similar in efficacy to intravenous bolus ketorolac 30 mg. * In a well controlled trial, single-dose HPbetaCD diclofenac 75 mg intravenous bolus injection was shown to be superior to PG-BA diclofenac 75 mg intravenous infusion with respect to TOTPAR over 4 hours, indicating faster onset of analgesia in the treatment of moderate or severe postoperative dental pain. Both HPbetaCD diclofenac and PG-BA diclofenac were superior to placebo. * HPbetaCD diclofenac was generally well tolerated during single-dose treatment of postoperative pain. The tolerability profile was similar to that of PG-BA diclofenac, but with a lower incidence of thrombophlebitis.