NSAIDs: Treatment and Pitt falls Jacques R Snyman (MD)
Slide 2
NSAIDs Classified as non-selective nsNSAIDS and Selective
NSAIDs nsNSAIDs are the typical old fashioned ibuprofen,
diclofenac, naproxen etc which blocks the cyclo-oxygenase enzymes 1
and 2 Selective NSAIDs include (higher affinity for COX 2) Coxibs
such as celecoxib, etoricoxib, etc Meloxicam, nimesolide etc
Slide 3
Major Pathways
Slide 4
NSAID Physiology The physiologic action of COX-1 includes the
normal, physiological production of prostanoids, which are involved
in the maintenance of the gastrointestinal (GI) mucosa and platelet
aggregation: Inhibition of this constitutively expressed enzyme
results in e.g.: decreased mucus and bicarbonate production from
the GI mucosa. reduced mucosal blood flow and inhibition of
epithelial proliferation. inhibition of coagulation inhibition of
inflammation shifts renal medullary perfusion
Slide 5
NSAID Physiology COX-2 is generally an inducible enzyme
released by cytokines, mitogens and endotoxins in inflammatory
cells and is also responsible for prostaglandin production in
inflamed tissues: selective inhibition of this enzyme results in
relief of pain and inflammation with a mitigated risk of
gastrointestinal complications, (this led to the development of the
coxibs) COX-2 inhibition results in reduced tumor genesis,
especially development of colorectal adenomas shifts renal blood
flow (influences auto-regulation in the stressed kidney)
Slide 6
Prostaglandin inhibitory activity correlates to
anti-inflammatory effect
Slide 7
NSAID: MECHANISM OF ACTION Non-steroidal anti-inflammatory
drugs (NSAIDs) All NSAIDs inhibit the cyclooxygenase required for
conversion of arachidonic acid to endoperoxide intermediate (PGG2
and PGH2). NSAIDs inhibit prostaglandin and thromboxane synthesis,
they are potent inhibitors of cyclooxygenase and eliminate all
prostaglandins and thromboxanes in every cell they reach
Prostaglandins and thromboxanes play crucial roles in: Pain
Inflammation Fever Excessive blood clotting
Slide 8
NSAIDS AND THE HEART What are the risks?
Slide 9
Aspirin Aspirin is the prototype anticoagulant for
cardiovascular protection (arterial side) Acetylates the COX 1 and
2 enzymes for the life span of the platelet (duration is dependant
on new platelet production) Irreversible inhibition Endothelium
escapes (COX produced by new coding from DNA) Platelet has no
nucleus Vasodilatation and inhibition of coagulation is PGI 2
dependent from endothelium
Slide 10
Arachidonic acid metabolism via cyclooxygenase-1 and
cyclooxygenase-2 in the cardiovascular system. [Schrr et al.
2005].
Slide 11
Inflammation drives Plaque Rupture
Slide 12
NSAIDS AND THE KIDNEY Does it matter?
Slide 13
NSAID Physiology (Kidney) COX-2 enzyme is expressed
constitutively in the adult mammalian renal cortex, macula densa,
thick ascending limb, interstitial cells in the inner medulla, and
papilla and podocyte, likely responsible for the adverse
cardio-renal effects seen with some COX-2 inhibitors [Nantel et al.
1999; Guan et al. 1997; Komhoff et al. 1997; Harris and Breyer,
2001]. Renal COX-2 expression has been found to be up-regulated in
renal ischemia and salt-depleted states, suggesting that COX-2
derived prostanoids may play an important role in maintaining
medullary blood supply, salt excretion, and systemic blood pressure
[Nantel et al. 1999; Guan et al. 1997; Komhoff et al. 1997; Harris
and Breyer 2001]. Renin-release and renal prostacyclin synthesis
have been demonstrated to be COX-2 dependent [Stichtenoth et al.
2005]. Evidence suggests that specific COX-2 inhibition may induce
renal ischemia, dyselectrolytemia, and an abnormal blood pressure
response [Harris et al. 1994], leading to sodium and fluid
retention and a decreased GFR [Whelton et al. 2001; Catella- Lawson
et al. 1999; Rossat et al. 1999].
Slide 14
RISK Who is at risk and why?
Slide 15
Adverse Cardiovascular Effects of NSAIDs: Driven by Blood
Pressure, or Edema? Ashish Aneja MD; Michael E. Farkouh MD, MSc
Ther Adv Cardiovasc Dis. 2008;2(1):53-66. The harmful cardio-renal
effects of some nsNSAIDs are well described and thought to be
related to inhibition of prostanoid synthesis. COX-2 inhibitors
promised and delivered a lower incidence of gastrointestinal side
effects. However, the COX-2 inhibitors have not been found to be
devoid of cardio-renal side effects. Indeed, some of these agents
lead to increased blood pressure, an excessive risk of congestive
heart failure and pro-thrombotic effects, especially in high risk
populations. These deleterious effects, however, may not be
class-specific and possibly related to pharmacokinetics, enzyme
specificity and endothelium effects.
Slide 16
AEs: A class effect? However, these may not be class effects,
at least in clinically used doses of all COX-2 inhibitors as shown
in randomized trials and from epidemiological data. Some
investigators have explained these differences by the degree and
specificity of COX-2 inhibition and also by their metabolism and
pharmacokinetics [Warner et al.]. Evidence suggests that rofecoxib
has stronger COX-2 selectivity than others [Chang and Harris 2005]
and this may account for the generally negative cardio-renal
effects with this agent in multiple randomized and non-randomized
studies. The COX-1 enzyme, present constitutively in the kidneys
and appears to play an important role in renal prostaglandin
synthesis. The predominant renal prostaglandins are PGE2 and PGI2
of which PGE2 influences sodium resorption in the thick ascending
loop of Henle and the collecting tubule. Prostaglandin E2 also
antagonizes the antidiuretic effect of vasopressin in the
collecting tubule [Schlondorff 1993].
Slide 17
PI What is registered
Slide 18
Common Warnings in Package Inserts patients with congestive
heart failure (NYHA II IV) established ischaemic heart disease,
peripheral arterial disease and/or cerebrovascular disease
perioperative analgesia in the setting of coronary artery bypass
surgery (CABG)
Slide 19
RENAL SIDE EFFECTS COX and the Kidney
Slide 20
Renal Side Effects of Etoricoxib Data from 4770 patients were
included in this Meta-analysis. Most patients were women and most
were white (68.0%, 83.3% respectively). The mean (SD) age at
baseline ranged from 53.6 (12.1) to 62.2 (8.4) years. Overall, the
incidence of renal AEs was low and generally similar between the
active-treatment groups. In the placebo; etoricoxib 60-, 90-, and
120-mg; naproxen; and ibuprofen groups, the incidences of
hypertension were 2.0%, 4.0%, 3.4%, 4.7%, 2.9%, and 6.6%,
respectively The only significant difference found was the
incidence of hypertension with etoricoxib 90 mg/d versus that with
placebo (P = 0.001); however, the rates of hypertension observed
with etoricoxib at any dosage were not clinically meaningfully
different versus comparator NSAIDs. Based on this combined data
review, the risks for renal AEs were generally similar to those
found with the comparator NSAIDs : naproxen 1000 mg/d and ibuprofen
2400 mg/d. Clin Ther. 2004;26:70-83.
Slide 21
Percent difference (95% Cl) versus placebo in incidence of
investigator-reported hypertension adverse effects
Slide 22
Effects of Nonsteroidal Anti-Inflammatory Drugs on Urinary
Sodium Excretion, Blood Pressure, and Other Renal Function
Indicators in Elderly Subjects Consuming a Controlled Sodium
Diet
Slide 23
Multicenter, double-blind, randomized, placebo controlled,
parallel- group study assessed renal function during dosing with
etoricoxib 90 mg daily, celecoxib 200 mg twice daily, and naproxen
500 mg twice daily: Male and female subjects 60 to 81 years old (n
= 85), in sodium balance on a controlled, normal sodium diet, were
treated for 15 days. There were no clinically meaningful
between-treatment differences in urinary sodium excretion,
creatinine clearance, body weight, or serum electrolytes during the
2 weeks of treatment. Etoricoxib and celecoxib had no effect on the
urinary thromboxane metabolite, 11-dehydrothromboxane B2, while
significantly decreasing the urinary prostacyclin metabolite,
2,3-dinor-6-keto PGF1. J. Clin. Pharmacol. 2007; 47; 1521
Slide 24
Effects of Nonsteroidal Anti-Inflammatory Drugs on Urinary
Sodium Excretion, Blood Pressure, and Other Renal Function
Indicators in Elderly Subjects Consuming a Controlled Sodium Diet:
Sodium Excretion
Slide 25
Hourly mean changes from baseline for ambulatory systolic blood
pressure (mm Hg) on day 14
Slide 26
Effects of Nonsteroidal Anti-Inflammatory Drugs on Urinary
Sodium Excretion, Blood Pressure, and Other Renal Function
Indicators in Elderly Subjects Consuming a Controlled Sodium Diet
Ambulatory systolic blood pressures were significantly higher than
placebo for all treatments, with moderately greater increases for
etoricoxib relative to other active treatments on day 14 Ambulatory
diastolic blood pressures were significantly higher than placebo
for etoricoxib and naproxen but not for celecoxib
Slide 27
CARDIOVASCULAR OUTCOMES Does it matter?
Slide 28
Cardiovascular outcomes with etoricoxib and diclofenac in
patients with osteoarthritis and rheumatoid arthritis in the
Multinational Etoricoxib and Diclofenac Arthritis Long-term (MEDAL)
programme: a randomised comparison Cyclo-oxygenase-2 (COX-2)
selective inhibitors have been associated with an increased risk of
thrombotic cardiovascular events in placebo-controlled trials, but
no clinical trial has been reported with the primary aim of
assessing relative cardiovascular risk of these drugs compared with
traditional non-steroidal anti- inflammatory drugs (NSAIDs). The
MEDAL programme was designed to provide a precise estimate of
thrombotic cardiovascular events with the COX-2 selective inhibitor
etoricoxib versus the traditional NSAID diclofenac.
Slide 29
Cardiovascular outcomes with etoricoxib and diclofenac in
patients with osteoarthritis and rheumatoid arthritis in the
Multinational Etoricoxib and Diclofenac Arthritis Long-term (MEDAL)
programme: a randomised comparison 34 701 patients (24 913 with
osteoarthritis and 9 787 with rheumatoid arthritis) enrolled.
Average treatment duration was 18 months (SD 118). 320 patients in
the etoricoxib group and 323 in the diclofenac group had thrombotic
cardiovascular events, yielding event rates of 124 and 130 per 100
patient-years and a hazard ratio of 095 (95% CI 081111) for
etoricoxib compared with diclofenac. Interpretation Rates of
thrombotic cardiovascular events in patients with arthritis on
etoricoxib are similar to those in patients on diclofenac with
long- term use of these drugs.
Slide 30
Incidence of thrombotic cardiovascular (CV) events in
prespecified subgroups, per-protocol
Slide 31
META ANALYSES Pooled data
Slide 32
Adverse Cardio-renal and Blood Pressure Effects of NSAIDs A
meta-analysis investigating the adverse cardio-renal effects of
nsNSAIDs include fifty four studies with 123 NSAID treatment arms.
The mean age: 46 years The vast majority (92%) of AEs were
hypertension. The increase in mean arterial pressure was 3.59 mm Hg
for indomethacin (57 treatment arms), 3.74 mm Hg for naproxen (four
arms), and 0.49 mm Hg for piroxicam In this short-term study,
NSAIDs varied considerably in their effect on blood pressure. Of
the drugs studied, indomethacin and naproxen were associated with
the largest increases in blood pressure. The average effects of
piroxicam, aspirin, ibuprofen, and sulindac were negligible [Pope
et al. 1993].
Slide 33
Adverse Cardio-renal and Blood Pressure Effects of NSAIDs A
subsequent meta-analysis of 38 randomized trials and 12 randomized
but not placebo-controlled trials studying the effect of nsNSAIDs
on blood pressure suggested that nsNSAIDs elevated supine mean
blood pressure by 5.0 mm Hg but had no effect on variables other
than blood pressure. In this study, nsNSAIDs antagonized the
antihypertensive effect of beta-blockers (blood pressure elevation,
6.2 mm Hg) more than with vasodilators and diuretics [Johnson et
al. 1994].
Slide 34
Adverse Cardio-renal and Blood Pressure Effects of NSAIDs In a
single-blind, randomized, cross-over study of 29 healthy elderly
subjects, given either celecoxib, 200 mg twice daily for 5 days,
followed by celecoxib 400 mg twice daily for the next 5 days, or
naproxen 500 mg twice daily for 10 days [Whelton et al. 2000],
naproxen resulted in a greater decrease in glomerular filtration
rate (5.31 mL/min per 1.73 m2) compared with celecoxib (0.86 mL/min
per 1.73 m2) after the first dose. The treatment difference became
statistically significant on day 6 (7.53 vs 1.11 mL/min per 1.73 m2
for naproxen and celecoxib, respectively; p = 0.004). Small,
transient decreases (p < 0.05) in urinary sodium excretion were
observed after the initiation of both celecoxib and naproxen
treatment. The results indicated for the first time in a clinical
study that cyclooxygenase 2-specific inhibition in healthy elderly
subjects might spare renal hemodynamic function, although the
effects on sodium excretion appeared to be similar to those of
nonspecific cyclooxygenase inhibitors such as naproxen.
Slide 35
Adverse Cardio-renal and Blood Pressure Effects of NSAIDs The
SUCCESS VI study performed a head to head comparison between
celecoxib and rofecoxib with regards to their effect on blood
pressure. This study was a 6-week, randomized, parallel-group,
double blind trial in patients with osteoarthritis who were more
than or equal to 65 years of age and on antihypertensive agents.
Patients received once-daily celecoxib 200 mg or rofecoxib 25 mg.
The primary endpoints were the development of edema, changes in
systolic blood pressure, and changes in diastolic blood pressure as
measured at any time point in the study.
Slide 36
Adverse Cardio-renal and Blood Pressure Effects of NSAIDs Eight
hundred and ten patients received study medication (celecoxib, n =
411; rofecoxib, n = 399). Nearly twice as many rofecoxib- compared
with celecoxib-treated patients experienced edema (9.5% vs 4.9%, p
= 0.014). Systolic blood pressure increased significantly in 17% of
rofecoxib- treated patients compared with 11% of celecoxib-treated
patients (p = 0.032) at any study time point. Diastolic blood
pressure increased in 2.3% of rofecoxib compared with 1.5% of
celecoxib-treated patients (p = 0.44). At week 6, the change from
baseline in mean systolic blood pressure was +2.6 mmHg for
rofecoxib compared with 0.5 mmHg for celecoxib (p = 0.007). This
study highlighted the differences in adverse cardio-renal effects
of COX-2 inhibitors partly explaining the adverse cardiovascular
effects seen with rofecoxib [Whelton et al. 2001].
Slide 37
WHY IS THERE A DIFFERENCE? Who is at risk?
Slide 38
Possible Mechanisms Associated With Variable Cardiovascular
Risk Profiles With COX-2 Inhibitors In principle, all COX-2
inhibitors are likely to have an adverse cardiovascular profile
because the vasodilatory prostaglandin, PGI 2 (prostacyclin) is
derived predominantly from the COX-2 enzyme tilting the balance
towards a greater thromboxane- A2 (TXA2) production [FitzGerald,
2003]. However, in clinical trials, the harm signal has been noted
more frequently with rofecoxib than celecoxib pointing to other
mechanisms that can account for these clinically observed
differences.
Slide 39
Possible Mechanisms Associated With Variable Cardiovascular
Risk Profiles With COX-2 Inhibitors Some of these differences have
been explained by rofecoxib's more selective COX-2 inhibition, a
longer elimination half-life and tendency to accumulate, greater
oral bioavailability, and differences in pathways of hepatic
metabolism [Crofford et al. 2006]
Slide 40
Possible Mechanisms Associated With Variable Cardiovascular
Risk Profiles With COX-2 Inhibitors The COX-2 enzyme, while absent
in healthy vasculature, is expressed in atherosclerotic lesions
[Schonbeck et al. 1999] and in transplant atherosclerosis [Baker et
al. 1999]. Strong evidence for a role of the COX-2 enzyme in
athero- thrombosis has been demonstrated by a reduced risk of MI
and stroke in carriers of a COX-2 gene polymorphism, which reduces
the expression of the COX-2 gene in plaque macrophages [Cipollone
et al. 2004]. In the diseased vasculature, COX-2 is expressed in
macrophages/foam cells, medial smooth muscle cells, endothelial
cells, and in the vasa vasorum, suggesting a role in plaque
vulnerability [Baker et al. 1999].
Slide 41
Possible Mechanisms Associated With Variable Cardiovascular
Risk Profiles With COX-2 Inhibitors It is not clear whether COX-2
inhibition per se results in thrombogenesis. It has been postulated
that while all COX-2 inhibitors may result in prostanoid imbalance,
treatment with celecoxib in an animal study resulted in improvement
in endothelial function whereas rofecoxib and diclofenac had no
effect on it [Hermann et al. 2003].
Slide 42
Possible Mechanisms Associated With Variable Cardiovascular
Risk Profiles With COX-2 Inhibitors New evidence also suggests that
the harmful effects of celecoxib from PGI 2 inhibition may be
counterbalanced by its beneficial effects on endothelial function,
inflammation, oxidation, the L-arginine/nitric oxide (NO) and Jun
N-terminal kinase pathways. Since NO is a powerful vasodilator and
also reduces leukocyte proliferation, migration, adhesion, and
vascular inflammation, these pathways are probably suffice in
counteracting the TXA 2 effects [Crofford et al. 2006].
Slide 43
Possible Mechanisms Associated With Variable Cardiovascular
Risk Profiles With COX-2 Inhibitors COX-2 independent effect of
celecoxib may counterbalance the adverse effect from COX-2
dependent prostanoid imbalance, accounting for neutrality of
clinical effect in most clinical trials. Another argument
underscoring the importance of the mechanisms cited above over and
above the TXA 2 and PGI 2 hypothesis was the relative lack of
protection for cardiovascular events by aspirin and clopidogrel
supplementation in a valdecoxib study [Nussmeier et al. 2005]. The
attenuation of a neutral cardiovascular effect with celecoxib when
used at a higher dose also supports the role of pharmacokinetics in
the overall cardiovascular risk profile, as demonstrated in the APC
trial [Bertagnolli et al. 2006].
Slide 44
META-ANALYSES Not the End
Slide 45
Cardiovascular Safety of Non-Steroidal Anti-Inflammatory Drugs;
Network Meta-Analysis Sven Trelle; Stephan Reichenbach; Simon
Wandel; Pius Hildebrand; Beatrice Tschannen; Peter M Villiger;
Matthias Egger; Peter Jni Posted: 01/27/2011; BMJ Objective: To
analyse the available evidence on cardiovascular safety of
non-steroidal anti- inflammatory drugs. Data synthesis: 31 trials
in 116 429 patients with more than 115 000 patient years of
follow-up were included. Patients were allocated to naproxen,
ibuprofen, diclofenac, celecoxib, etoricoxib, rofecoxib,
lumiracoxib, or placebo.
Slide 46
Network of comparisons included in analyses. Solid lines
represent direct comparisons within randomised controlled trials.
Numbers denote trials comparing corresponding interventions, with
overall number of patient years of follow-up in brackets
Slide 47
Cardiovascular Safety of Non-Steroidal Anti-Inflammatory Drugs;
Network Meta-Analysis Sven Trelle; Stephan Reichenbach; Simon
Wandel; Pius Hildebrand; Beatrice Tschannen; Peter M Villiger;
Matthias Egger; Peter Jni Posted: 01/27/2011; BMJ Compared with
placebo, rofecoxib was associated with the highest risk of
myocardial infarction (rate ratio 2.12, 95% credibility interval
1.26 to 3.56), followed by lumiracoxib (2.00, 0.71 to 6.21).
Ibuprofen was associated with the highest risk of stroke (3.36,
1.00 to 11.6), followed by diclofenac (2.86, 1.09 to 8.36).
Etoricoxib (4.07, 1.23 to 15.7) and diclofenac (3.98, 1.48 to 12.7)
were associated with the highest risk of cardiovascular death.
Conclusions: Although uncertainty remains, little evidence exists
to suggest that any of the investigated drugs are safe in
cardiovascular terms. Naproxen seemed least harmful. Cardiovascular
risk needs to be taken into account when prescribing any
non-steroidal anti-inflammatory drug.
Slide 48
Estimates of rate ratios for non-steroidal anti-inflammatory
drugs compared with placebo. NSAID=non-steroidal anti-inflammatory
drug; APTC=Antiplatelet Trialists' Collaboration
Slide 49
CONCLUSION The END
Slide 50
Summary None of the partially selective NSAIDs such as
meloxicam or nabumetone are associated with any clear safety
advantage when compared with non-selective NSAIDs. Evidence from
clinical trials suggests that the increased rate of cardiovascular
events associated with coxib use is approximately three per 1000
patients per year. The increased cardiovascular risk attributed to
coxibs is thought to be due to suppression of prostaglandin I 2
production (endothelial lesion is COX 2 dependent) which in turn
causes elevation of blood pressure, accelerated atherosclerosis and
a heightened thrombotic response to rupture of an atherosclerotic
plaque.
Slide 51
Summary The cardiovascular safety of classical NSAIDs is
unclear and may not be different to that of coxibs. A consistent
pattern has emerged for increased cardiovascular risk for all
coxibs. The increased cardiovascular risk extends across all
NSAIDs; however the mechanism may not be related to COX 2
inhibition alone and may be due to another mechanism.
Slide 52
Summary The increased risk is independent of the use of
concomitant aspirin therapy; in fact the addition of aspirin
counteracts the beneficial protective effect of the coxibs on the
gut. Selective COX 2 inhibitors are a rational choice for patients
with a low cardiovascular risk who have a history of
gastro-intestinal events. In patients who have cardiovascular
disease or who are at risk of cardiovascular events, it is
important to avoid NSAIDs if possible.