Chronic renal disease and papillary necrosis associated with the long-term use of nonsteroidal anti-inflammatory drugs as the sole or predominant analgesic

Acute kidney injury associated with non-steroidal anti-inflammatory drugs

Non-steroidal anti-inflammatory drugs (NSAIDs) are ones of the commonly prescribed drugs worldwide. They primarily inhibit cyclooxygenase (COX) enzyme which is responsible for conversion of phospholipids to various prostaglandins (PGs). Disruption in PGs production affects the kidneys in several ways, including vasoconstriction that may result in ischemic acute kidney injury (AKI) in at-risk patients. They also impair salt and water excretion, leading to edema and hypertension. Other complications include hyperkalemia, hyponatremia, nephrotic syndrome, acute interstitial nephritis and chronic kidney disease progression. AKI from NSAIDs is usually reversible with favorable prognosis after discontinuation of NSAIDs. Avoidance of NSAIDs exposure is extremely important, especially among high-risk patients.

Nonsteroidal anti-inflammatory drugs in end-stage kidney disease: dangerous or underutilized?

Introduction: Nonsteroidal anti-inflammatory drugs (NSAIDs) are a popular class of analgesic and anti-inflammatory medications, but their use is often avoided in end-stage kidney disease (ESKD) patients due to their reputation for nephrotoxic side effects. This removes a useful agent from the analgesic arsenal, even as ESKD patients suffer from proportionally more severe chronic pain than the general population as well as from a large reliance on opioid medications. Areas Covered: This paper reviews the current literature to comprehensively define the pharmacologic mechanisms and adverse effects of NSAIDs and reassesses the viability of their use in ESKD patients. Expert opinion: The evidence directly examining the impact of NSAIDs on long-term outcomes in ESKD is limited. Further study quantifying the risk of NSAID use - especially in dialysis-dependent patients - is warranted. Given the difficulty in achieving adequate pain control in ESKD patients, limited use of NSAIDs in these patients may yet be justified.

Renal Medullary Interstitial COX-2 (Cyclooxygenase-2) Is Essential in Preventing Salt-Sensitive Hypertension and Maintaining Renal Inner Medulla/Papilla Structural Integrity

COX (cyclooxygenase)-derived prostaglandins regulate renal hemodynamics and salt and water homeostasis. Inhibition of COX activity causes blood pressure elevation. In addition, chronic analgesic abuse can induce renal injury, including papillary necrosis. COX-2 is highly expressed in the kidney papilla in renal medullary interstitial cells (RMICs). However, its role in blood pressure and papillary integrity in vivo has not been definitively studied. In mice with selective, inducible RMIC COX-2 deletion, a high-salt diet led to an increase in blood pressure that peaked at 4 to 5 weeks and was associated with increased papillary expression of AQP2 (aquaporin 2) and ENac (epithelial sodium channel) and decreased expression of cystic fibrosis transmembrane conductance regulator. With continued high-salt feeding, the mice with RMIC COX-2 deletion had progressive decreases in blood pressure from its peak. After return to a normal-salt diet for 3 weeks, blood pressure remained low and was associated with a persistent urinary concentrating defect. Within 2 weeks of institution of a high-salt diet, increased apoptotic RMICs and collecting duct cells could be detected in papillae with RMIC deletion of COX-2, and by 9 weeks of high salt, there was a striking loss of the papillae. Therefore, RMIC COX-2 expression plays a crucial role in renal handling water and sodium homeostasis, preventing salt-sensitive hypertension and maintaining structural integrity of papilla.

Effect of nitric oxide-releasing derivative of indomethacin on Prevotella intermedia lipopolysaccharide-induced production of proinflammatory mediators in murine macrophages

The purpose of this study was to investigate the influences of NCX 2121, a nitric oxide (NO)-releasing derivative of indomethacin, upon the generation of proinflammatory mediators using murine macrophages activated by lipopolysaccharide (LPS) isolated from Prevotella intermedia, which is one of the pathogens implicated in periodontal diseases. Inducible NO synthase (iNOS)-derived NO, IL-1β and IL-6 as well as their relevant mRNA were significantly attenuated by NCX 2121 in RAW264.7 cells activated by P. intermedia LPS. NCX 2121 was much more effective than the parental compound indomethacin in reducing these proinflammatory mediators. NCX 2121 triggered induction of heme oxygenase-1 (HO-1) in cells exposed to P. intermedia LPS, and its inhibitory influence upon P. intermedia LPS-elicited NO generation was notably blocked by SnPP treatment. NCX 2121 attenuated NF-κB-dependent SEAP release induced by P. intermedia LPS. NCX 2121 did not display inhibitory action towards IκB-α degradation triggered by LPS. Instead, it significantly diminished nuclear translocation as well as DNA-binding action of NF-κB p50 subunit elicited by P. intermedia LPS. Further, NCX 2121 significantly up-regulated SOCS1 mRNA expression in cells challenged with P. intermedia LPS. In summary, NCX 2121 down-regulates P. intermedia LPS-elicited generation of NO, IL-1β and IL-6 in murine macrophages in a mechanism that involves anti-inflammatory HO-1 induction as well as decrement of NF-κB activation, which may be associated with SOCS1 expression. NCX 2121 may have potential benefits as a host immunomodulatory agent for the therapy of periodontal disease.

Effects of nonsteroidal anti-inflammatory drugs on the renal excretion of indoxyl sulfate, a nephro-cardiovascular toxin, in rats

Chronic kidney disease (CKD) is a health problem worldwide. Indoxyl sulfate (IS) is a nephro-cardiovascular toxin accumulated in CKD patients and cannot be removed through hemodialysis. The renal excretion of IS was mediated by organic anion transporters (OATs) OAT 1 and OAT 3. Because a number of nonsteroidal anti-inflammatory drugs (NSAIDs) have been reported to inhibit OATs, we hypothesize that NSAIDs might inhibit the renal excretion of IS. Rats were intravenously injected IS with and without diclofenac, ketoprofen or salicylic acid, individually. Blood samples were collected at predetermined time points and the concentrations of IS were determined by HPLC method. The results showed that diclofenac and ketoprofen at 10.0mg/kg significantly decreased the systemic clearance of IS by 71% and 82%, and increased the MRT of IS by 106% and 105%, respectively, whereas salicylic acid did not exhibit significant effects. Cell studies indicated that diclofenac and ketoprofen inhibited the uptake of IS mediated by OAT 1 and OAT 3. In conclusion, diclofenac and ketoprofen inhibited the excretion of IS through inhibition on OAT 1 and OAT 3.

A Center-Based Approach to a Transplant Employment Program

The return to work after transplantation has been actively discussed in the transplant community for years. However, despite the desire for transplant practitioners to have recipients return to being healthy, contributing members of society as well as return to work, practitioners often passively support the sick role. We discovered that patients who are returning to work after transplantation may have been out of the work force for several years, and require assistance that we as healthcare providers were unable or untrained to provide. An employment specialist was added to the transplant staff and became a vital part of our attempts to create a proactive employment atmosphere and enhance our patients' quality of life. Adding an advocate for employment in our center has also facilitated the shift in our thinking and approach to care from the sick role to one of rehabilitation and from reactive to proactive. This change in attitude has assisted in empowering our recipients to feel as if they can truly resume a normal life.

Use of Structured Self-Monitoring in Transplant Education

A self-assessment instrument for use at home by transplant recipients was developed to help foster partnership between patients and their healthcare provider. Self-monitoring at home has not replaced the need for close follow-up but does allow patients to provide concrete data to their healthcare provider in order to promote earlier detection of and response to adverse events. Patients are taught the essentials of self-monitoring while they are in the hospital for their transplant. Patients who perform routine self-assessment would be able to detect and provide information about problems early in the course of events. Thus, early intervention could potentially decrease the severity of the problem and prevent repeated hospitalizations. The concern that patients would not be able to perform a reliable self-assessment was unfounded; patients exceeded expectations and embraced the opportunity to communicate physical signs and symptoms effectively.

NCX 4040, a nitric oxide-donating aspirin derivative, inhibits Prevotella intermedia lipopolysaccharide-induced production of proinflammatory mediators in murine macrophages

In this study, the effects and underlying mechanisms of NCX 4040, a nitric oxide (NO)-donating aspirin derivative, on the production of proinflammatory mediators were examined using murine macrophages exposed to lipopolysaccharide (LPS) from Prevotella intermedia, a pathogen implicated in the etiology of periodontal disease. NCX 4040 significantly reduced P. intermedia LPS-induced production of inducible NO synthase (iNOS)-derived NO, IL-1β and IL-6 as well as their mRNA expression in RAW264.7 cells. Notably, NCX 4040 was much more effective than the parental compound aspirin in reducing LPS-induced production of inflammatory mediators. NCX 4040 induced the expression of heme oxygenase-1 (HO-1) in cells treated with P. intermedia LPS, and the suppressive effect of NCX 4040 on LPS-induced NO production was significantly reversed by SnPP, a competitive HO-1 inhibitor. NCX 4040 did not influence LPS-induced phosphorylation of JNK and p38. IκB-α degradation as well as nuclear translocation and DNA-binding activities of NF-κB p65 and p50 subunits induced by P. intermedia LPS were significantly reduced by NCX 4040. Besides, LPS-induced phosphorylation of STAT1 and STAT3 was significantly down-regulated by NCX 4040. Further, NCX 4040 elevated the SOCS1 mRNA in cells stimulated with LPS. This study indicates that NCX 4040 inhibits P. intermedia LPS-induced production of NO, IL-1β and IL-6 in murine macrophages through anti-inflammatory HO-1 induction and suppression of NF-κB, STAT1 and STAT3 activation, which is associated with the activation of SOCS1 signaling. NCX 4040 could potentially be a promising tool in the treatment of periodontal disease, although further studies are required to verify this.

Nonsteroidal antiinflammatory drugs, cyclooxygenase-2, and the kidneys

Nonsteroidal antiinflammatory drugs (NSAIDs) are one of the most commonly used classes of medications in the world, which function by inhibiting the cyclooxygenase (COX) enzymes and downregulating the inflammatory pathway. COX enzymes are constitutively expressed in the kidneys and function to maintain a homeostatic environment in terms of maintaining the glomerular filtration rate, blood pressure, sodium, water, and osmotic regulation. When the COX enzymes are inhibited by NSAIDs, a multitude of renal and vascular complications occur. This article aims to enlighten primary care physicians of the complications that arise with NSAIDs from a renal perspective and to present some management strategies.

Analgesic use and the risk of kidney cancer: a meta-analysis of epidemiologic studies

Analgesics are the most commonly used over-the-counter drugs worldwide with certain analgesics having cancer prevention effect. The evidence for an increased risk of developing kidney cancer with analgesic use is mixed. Using a meta-analysis design of available observational epidemiologic studies, we investigated the association between analgesic use and kidney cancer risk. We searched the MEDLINE and EMBASE databases to identify eligible case-control or cohort studies published in English until June 2012 for three categories of analgesics: acetaminophen, aspirin or other non-steroidal anti-inflammatory drugs (NSAIDs). Study-specific effect estimates were pooled to compute an overall relative risk (RR) and its 95% confidence interval (CI) using a random-effects model for each category of the analgesics. We identified 20 studies (14 with acetaminophen, 13 with aspirin and five with other NSAIDs) that were performed in six countries, including 8,420 cases of kidney cancer. Use of acetaminophen and non-aspirin NSAIDs were associated with an increased risk of kidney cancer (pooled RR: 1.28; 95% CI: 1.15-1.44 and 1.25; 95% CI: 1.06-1.46, respectively). For aspirin use, we found no overall increased risk (pooled RR: 1.10; 95% CI: 0.95-1.28), except for non-US studies (five studies, pooled RR: 1.17; 95% CI: 1.04-1.33). Similar increases in risks were seen with higher analgesic intake. In this largest meta-analysis to date, we found that acetaminophen and non-aspirin NSAIDs are associated with a significant risk of developing kidney cancer. Further work is needed to elucidate biologic mechanisms behind these findings.

A large cohort study of nonsteroidal anti-inflammatory drugs and renal cell carcinoma incidence in the National Institutes of Health-AARP Diet and Health Study

AIM

Existing epidemiologic evidence for the association between nonsteroidal anti-inflammatory drugs (NSAIDs) and renal cell carcinoma (RCC) risk is inconsistent.

METHODS

We investigated the association between the use of aspirin and nonaspirin NSAIDs and RCC risk in the National Institutes of Health-American Association of Retired Persons (AARP) Diet and Health Study, for which 298,468 AARP members free of cancer, aged 50-71 years, completed a survey on use of NSAIDs (1996-1997). Multivariate Cox proportional hazards models were used to estimate the hazard ratio (HR).

RESULTS

The state cancer registry and mortality index linkage identified 1,084 incident RCC cases through 31 December 2006. No statistically significant associations between the use of aspirin or nonaspirin NSAIDs and RCC risk were found. Compared to nonuse of any NSAIDs, the multivariate-adjusted HRs were 0.95 (95 % CI 0.75-1.21) and 0.93 (95 % CI 0.68-1.26) for monthly use of aspirin and nonaspirin NSAIDs, respectively, 0.92 (95 % CI: 0.69-1.23) and 1.11 (95 % CI: 0.76-1.62) for weekly use, 0.87 (95 % CI: 0.69-1.11) and 1.06 (95 % CI: 0.75-1.48) for daily use; and 0.95 (95 % CI 0.78-1.14) for the use of both aspirin and nonaspirin NSAIDs. We found some suggestions of an increased risk of RCC associated with frequent NSAID use among participants who were <63 years and a reduced risk associated with aspirin use among those ≥63 years. No significant associations were found in other stratified analyses by gender, BMI, smoking, history of diabetes, or history of hypertension.

CONCLUSION

RCC risk was not significantly associated with NSAID use overall. The difference in association by age needs to be explored further.

Non-steroidal anti-inflammatory drugs and chronic kidney disease progression: a systematic review

BACKGROUND

Non-steroidal anti-inflammatory drugs (NSAIDs) are widely regarded as one risk factor, which influences chronic kidney disease (CKD) progression. However, previous literature reviews have not quantified the risk in moderate to severe CKD patients.

OBJECTIVE

To estimate the strength of association between chronic NSAID use and CKD progression.

METHODS

We conducted a systematic review and meta-analysis of observational general practice or population studies featuring patients aged 45 years and over. The electronic databases searched were MEDLINE, EMBASE, Cochrane, AMED, BNI and CINAHL until September 2011 without date or language restrictions. Searches included the reference lists of relevant identified studies, WEB of KNOWLEDGE, openSIGLE, specific journals, the British Library and expert networks. For relevant studies, random effects meta-analysis was used to estimate the association between NSAID use and accelerated CKD progression (estimated glomerular filtration rate decline ≥ 15 ml/min/1.73 m2).

RESULTS

From a possible 768 articles, after screening and selection, seven studies were identified (5 cohort, 1 case-control and 1 cross-sectional) and three were included in the meta-analysis. Regular-dose NSAID use did not significantly affect the risk of accelerated CKD progression; pooled odds ratio (OR) = 0.96 (95%CI: 0.86-1.07), but high-dose NSAID use significantly increased the risk of accelerated CKD progression; pooled OR = 1.26 (95%CI: 1.06-1.50).

CONCLUSIONS

The avoidance of NSAIDs in the medium term is unnecessary in patients with moderate to severe CKD, if not otherwise contraindicated. As the definition of high-dose of NSAID use remains unclear, the lowest effective dose of NSAIDs should be prescribed where indicated.

Prospective evaluation of analgesic use and risk of renal cell cancer

BACKGROUND

Epidemiologic data suggest that analgesic use increases the risk of renal cell cancer (RCC), but few prospective studies have been published. We investigated the association between analgesic use and RCC in 2 large prospective studies.

METHODS

We examined the relationship between analgesic use and RCC risk in the Nurses' Health Study and the Health Professionals Follow-up Study. Use of aspirin, other nonsteroidal anti-inflammatory drugs (NSAIDs), and acetaminophen was ascertained in 1990 in the Nurses' Health Study and in 1986 in the Health Professionals Follow-up Study, and every 2 years thereafter. We evaluated baseline and duration of use of analgesics.

RESULTS

During follow-up of 16 years among 77,525 women and 20 years among 49,403 men, we documented 333 RCC cases. Aspirin and acetaminophen use were not associated with RCC risk. However, regular use of nonaspirin NSAIDs was associated with an increased RCC risk; the pooled multivariate relative risk was 1.51 (95% confidence interval, 1.12-2.04) at baseline. The absolute risk differences for users vs nonusers of nonaspirin NSAIDs were 9.15 per 100 000 person-years in women and 10.92 per 100,000 person-years in men. There was a dose-response relationship between duration of nonaspirin NSAID use and RCC risk; compared with nonregular use, the pooled multivariate relative risks were 0.81 (95% confidence interval, 0.59-1.11) for use less than 4 years, 1.36 (0.98-1.89) for 4 to less than 10 years, and 2.92 (1.71-5.01) for use for 10 or more years (P < .001 for trend).

CONCLUSION

Our prospective data suggest that longer duration of use of nonaspirin NSAIDs may increase the risk of RCC.

Pharmacoeconomic impact of adverse events of long-term opioid treatment for the management of persistent pain

Opioids are the most powerful analgesic drugs currently available and consequently form an essential part of the treatment options for malignant and non-malignant chronic pain. However, the benefits of these medications can be offset by gastrointestinal adverse events such as nausea, vomiting and constipation, as well as adverse events affecting the CNS. These occur relatively frequently in patients receiving long-term opioids for pain relief and are a cause of additional patient suffering and reduced work and social functioning, measured as reductions in quality-of-life outcomes. Consequently, adverse events are often the cause of treatment non-compliance or discontinuation (non-persistence). A literature search was conducted using BIOSIS Previews, EMBASE, Cochrane Collaboration and MEDLINE databases to identify references with specific relevance to the measurement of health outcomes related to adverse events of long-term opioid treatment of chronic pain. The results of this search highlighted that clinical interventions required to manage adverse events associated with opioids, and to provide alternative methods of pain control, both incur direct costs. These are largely driven by the cost of medical consults and drug supplies. Indirect costs are generated from work absences and reduced social functioning. Estimated preference ratings, providing an insight into the trade-off between effective pain control and adverse events, have shown that utility decrements associated with an increase in adverse-event severity were similar in size to those caused by a shift from well controlled to poorly controlled pain. Given the rising prevalence of chronic pain conditions (affecting one in five adult Europeans), the direct and indirect costs incurred from the management of adverse events with long-term opioids are likely to be multiplied, contributing to the socioeconomic burden of chronic pain. For this reason, the adverse-event profile of opioid-based analgesics should be improved to achieve more efficient long-term pain control.

Pharmacoeconomic impact of adverse events of long-term opioid treatment for the management of persistent pain

Opioids are the most powerful analgesic drugs currently available and consequently form an essential part of the treatment options for malignant and non-malignant chronic pain. However, the benefits of these medications can be offset by gastrointestinal adverse events such as nausea, vomiting and constipation, as well as adverse events affecting the CNS. These occur relatively frequently in patients receiving long-term opioids for pain relief and are a cause of additional patient suffering and reduced work and social functioning, measured as reductions in quality-of-life outcomes. Consequently, adverse events are often the cause of treatment non-compliance or discontinuation (non-persistence). A literature search was conducted using BIOSIS Previews, EMBASE, Cochrane Collaboration and MEDLINE databases to identify references with specific relevance to the measurement of health outcomes related to adverse events of long-term opioid treatment of chronic pain. The results of this search highlighted that clinical interventions required to manage adverse events associated with opioids, and to provide alternative methods of pain control, both incur direct costs. These are largely driven by the cost of medical consults and drug supplies. Indirect costs are generated from work absences and reduced social functioning. Estimated preference ratings, providing an insight into the trade-off between effective pain control and adverse events, have shown that utility decrements associated with an increase in adverse-event severity were similar in size to those caused by a shift from well controlled to poorly controlled pain. Given the rising prevalence of chronic pain conditions (affecting one in five adult Europeans), the direct and indirect costs incurred from the management of adverse events with long-term opioids are likely to be multiplied, contributing to the socioeconomic burden of chronic pain. For this reason, the adverse-event profile of opioid-based analgesics should be improved to achieve more efficient long-term pain control.

Modulation of carcinogen metabolism by nitric oxide-aspirin 2 is associated with suppression of DNA damage and DNA adduct formation

Nitric oxide (NO)-donating non-steroidal anti-inflammatory drugs (NSAIDs) represent a promising new class of drugs developed to provide a safer alternative than their conventional NSAID counterparts in chemoprevention. We tested the effects of NO-aspirin 2 on Phase I and Phase II carcinogen-metabolizing enzymes. In HepG2 human hepatoma cells and in LS180 colonic adenocarcinoma cells, NO-aspirin 2 inhibited 2,3,7,8-tetrachlordibenzo-p-dioxin (TCDD)-induced cytochrome P450 (CYP) enzyme activity and CYP1A1 and CYP1A2 mRNA expression. These effects were further characterized as being mediated through transcriptional regulation: NO-aspirin 2 inhibited binding of ligand (TCDD)-activated aryl hydrocarbon receptor to the CYP1A1 enhancer sequence; additionally, NO-aspirin 2 suppressed carcinogen-induced expression of CYP1A heterogeneous nuclear RNA. The fate of carcinogen metabolites depends not only on activation by CYP enzymes but also detoxification by Phase II enzymes. Both HepG2 and LS180 cells treated with NO-aspirin 2 showed an increase in glutathione S-transferase-P1 (GST-P1), glutamate-cysteine ligase (GCL), and NAD(P)H:quinone oxidoreductase-1 (NQO1) expression. Compared with two other NO-releasing compounds, diethylenetriamine-NO and the organic nitrate, isosorbide dinitrate, the inhibitory effects of NO-aspirin 2 on TCDD-induced CYP activity and mRNA expression were considerably more potent. Furthermore, aspirin alone had no inhibitory effect on TCDD-induced CYP activity, nor did aspirin up-regulate GCL, GST-P1, or NQO1 expression. Consequent to the effects on carcinogen-metabolizing enzymes, NO-aspirin 2 inhibited [3H]benzo[a]pyrene-DNA adduct formation and DNA damage elicited by TCDD or benzo[a]pyrene. Our results demonstrate that NO-aspirin 2 may be an effective chemopreventive agent by favorably affecting the inhibitory and enhancing effects of Phase I and Phase II carcinogen metabolism, thereby protecting DNA from carcinogenic insult.

Physiological regulation of prostaglandins in the kidney

Cyclooxygenase-derived prostanoids exert complex and diverse functions within the kidney. The biological effect of each prostanoid is controlled at multiple levels, including (a) enzymatic reactions catalyzed sequentially by cyclooxygenase and prostanoid synthase for the synthesis of bioactive prostanoid and (b) the interaction with its receptors that mediate its functions. Cyclooxygenase-derived prostanoids act in an autocrine or a paracrine fashion and can serve as physiological buffers, protecting the kidney from excessive functional changes during physiological stress. Through these actions, prostanoids play important roles in maintaining renal function, body fluid homeostasis, and blood pressure. Renal cortical COX2-derived prostanoids, particularly PGI2 and PGE2, play critical roles in maintaining blood pressure and renal function in volume-contracted states. Renal medullary COX2-derived prostanoids appear to have an antihypertensive effect in individuals challenged with a high-salt diet. Loss of EP2 or IP receptor is associated with salt-sensitive hypertension. COX2 also plays a role in maintaining renal medullary interstitial cell viability in the hypertonic environment of the medulla. Cyclooxygenase-derived prostanoids also are involved in certain pathological processes. The cortical COX2-derived PGI2 participates in the pathogenesis of renal vascular hypertension through stimulating renal renin synthesis and release. COX-derived prostanoids also appear to be involved in the pathogenesis of diabetic nephropathy. COXs, prostanoid synthases, and prostanoid receptors should provide fruitful targets for intervention in the pharmacological treatment of renal disease.

NSAID use and progression of chronic kidney disease

PURPOSE

The effects of nonselective and selective cyclooxygenase-2 specific (COX-2) nonsteroidal anti-inflammatory drug (NSAID) use on the progression of chronic kidney disease (CKD) is uncertain. Due to the high prevalence of both CKD and NSAID use in older adults, we sought to determine the association between NSAID use and the progression of CKD in an elderly community-based cohort.

METHODS

All subjects > or =66 years of age who had at least one serum creatinine measurement in 2 time periods (July-December, 2001 and July-December, 2003) were included. Multiple logistic regression analyses, including covariates for age, sex, baseline estimated glomerular filtration rate (eGFR), diabetes, and comorbidity were used to explore the associations of NSAID use on the primary (decrease in eGFR of > or =15 mL/min/1.73) and secondary (mean change in eGFR) outcomes.

RESULTS

A total of 10,184 subjects (mean age 76 years; 57% female) were followed for a median of 2.75 years. High-dose NSAID users (upper decile of cumulative NSAID exposure) experienced a 26% increased risk for the primary outcome (odds ratio [OR] 1.26, 95% confidence interval [CI], 1.04-1.53). A linear association between cumulative NSAID dose and change in mean GFR also was seen. No risk differential was identified between selective and nonselective NSAID users.

CONCLUSIONS

High cumulative NSAID exposure is associated with an increased risk for rapid CKD progression in the setting of a community-based elderly population. For older adult patients with CKD, these results suggest that nonselective NSAIDs and selective COX-2 inhibitors should be used cautiously and chronic exposure to any NSAID should be avoided.

Molecular characterization of cytotoxic and resistance mechanisms induced by NCX 4040, a novel NO-NSAID, in pancreatic cancer cell lines

Although non steroidal antiinflammatory drugs (NSAIDs) have been shown to be effective as chemopreventive agents, important side-effects limit their clinical use. A promising novel class of drugs, nitric oxide-donating NSAIDs (NO-NSAIDs), has been found to be more active than classical NSAIDs. This study explored the effect of the NO-donating aspirin derivative, NCX 4040, on three human pancreatic adenocarcinoma cell lines (Capan-2, MIA PaCa-2 and T3M4). NCX 4040 activity was compared with that of NCX 4016 (an NO(2)-positional isomer of NCX 4040), SNAP (a standard NO-releasing molecule), NCX 4042 (denitrated analog of NCX 4040), and aspirin. NCX 4040 showed a striking cytocidal activity in all cell lines, already inducing significant percentages of apoptotic cells at 10 muM in Capan-2 cell lines. This study focused on the biological mechanisms of sensitivity and resistance to NCX 4040, highlighting that the cytotoxic action of this drug may be due to the hyperexpression of Bax, its translocation to the mitochondria, the release of Cytochrome C, and the activation of caspases-9 and -3, overall in a p53-independent manner. Moreover, the use of a specific COX-2 inhibitor (NS 398) in the experimental models showed that COX-2 hyperexpression could partially explain the resistance mechanisms to NCX 4040.

Pro-apoptotic effect of a nitric oxide-donating NSAID, NCX 4040, on bladder carcinoma cells

Nitric oxide-releasing non steroidal anti-inflammatory drugs (NO-NSAIDs) are a promising class of compounds that cause cell cycle perturbations and induce apoptosis in cell lines from different tumors. We investigated the activity of a recently developed NO-NSAID (NCX 4040) in bladder cancer cell lines (HT1376 and MCR). Cells were treated with different drug concentrations for different exposure times. Cytostatic and cytocidal activity was tested by SRB assay and apoptosis was evaluated by TUNEL analysis, ANNEXIN V assay and fluorescence microscopy. To further investigate the cell death-inducing mechanisms of NCX 4040, we analyzed gp-170, caspase expression and mitochondrial membrane potential (Delta Psi) depolarization. NCX 4040 showed a striking cytocidal activity in both cell lines, reaching LC(50) at a 10-microM and 50-microM concentrations in HT1376 and in MCR cells, respectively, after an exposure of only 6 h followed by an 18-h washout. Apoptosis was triggered in up to 90% of cells and was associated with active caspase-3 expression and Delta Psi depolarization in both cell lines after a 6-h exposure. In conclusion, NCX 4040, which probably causes apoptosis via a mitochondrial-dependent mechanism, could prove to be a useful agent for improving bladder cancer treatment.

Frequent monthly use of selected non-prescription and prescription non-narcotic analgesics among U.S. adults

PURPOSE

Analgesics offer many benefits, however, chronic, long-term use may pose risks of adverse drug events. The objective of this study was to estimate frequent monthly non-narcotic analgesic use among U.S. adults, identifying socio-demographic trends and potentially at-risk groups.

METHODS

Analysis of adult medication use data from the 1999-2000 National Health and Nutrition Examination Survey household interview (n = 4880).

RESULTS

Some 20% of U.S. adults used non-prescription or prescription non-narcotic analgesics on a frequent basis, that is nearly every day for a month, at some point during their lifetime. Also, 14% of U.S. adults were currently using analgesics frequently. Aspirin was most commonly used (8%), followed by non-aspirin non-steroidal anti-inflammatory drugs (NANSAID, 3%) and acetaminophen (3%). Three-quarters of aspirin, 46% of NANSAID and 63% of acetaminophen users were long-term frequent monthly users (1+ years). Seven percent of frequent monthly analgesic users reported using two or more analgesics nearly every day during the month. Frequent analgesic use was most common among older adults and non-Hispanic whites with no differences by gender or education. Use patterns, however, varied by analgesic subgroups.

CONCLUSIONS

Frequent monthly non-narcotic analgesic use, especially of over-the-counter analgesics, is widely prevalent among U.S. adults. Health-care providers should heighten their awareness of this trend, and routinely monitor both non-prescription and prescription analgesic use in their patients to prevent adverse drug effects and inappropriate use.

C/EBPβ and Its Binding Element Are Required for NFκB-induced COX2 Expression Following Hypertonic Stress

NFkappaB plays a critical role mediating COX2 expression in renal medullary interstitial cells (RMICs). The trans-activating ability of NFkappaB can be modified by another nuclear factor C/EBPbeta that can physically bind to NFkappaB and regulate its activity. Because the COX2 promoter also contains a C/EBPbeta site adjacent to the NFkappaB site, the present study examined whether these two transcription factors cooperate to induce COX2 expression following hypertonic stress. Hypertonicity markedly induced COX2 expression in cultured medullary interstitial cells by immunoblot analysis. The tonicity-induced COX2 expression was suppressed by mutant IkappaB (IkappaBm) that blocks NFkappaB activation, demonstrating that tonicity-induced COX2 expression depends on NFkappaB activation. However, mutation of the NFkappaB site in the COX2 promoter failed to abolish tonicity-induced COX2 reporter activity. IkappaB kinase-1 (IKK1) significantly induced COX2-luciferase activity by 2.3-fold (n = 10, p < 0.01); mutation of the NFkappaB site also failed to abolish IKK1-stimulated COX2 reporter activity (86 +/- 3.1% of wild type, p > 0.05, n = 4). Interestingly, mutation of the C/EBPbeta site of the COX2 gene significantly reduced both IKK1 and hypertonicity-induced COX2 reporter activity (p < 0.01). To further examine the potential role of C/EBPbeta in tonicity-induced COX2 expression, a dominant negative C/EBPbeta-p20 was transduced into RMICs. C/EBPbeta-p20 markedly suppressed hypertonic (550 mOsm) induction of COX2 (immunoblot) to a similar extent as IkappaBm. No additional suppression was observed when both NFkappaB and C/EBPbeta were simultaneously blocked by IkappaBm and C/EBPbeta-p20. Interestingly, IKK-induced COX2 expression was not only blocked by IkappaBm, but also completely abolished by C/EBPbeta-p20. Further studies demonstrated physical association of C/EBPbeta to NFkappaB p65 by coimmunoprecipitation. Importantly, this interaction between C/EBPbeta and NFkappaB was greatly enhanced following hypertonic stress. These studies indicate C/EBPbeta is required for the transcriptional activation of COX2 by NFkappaB, suggesting a dominant role for the C/EBPbeta pathway in regulating induction of RMIC COX2 by hypertonicity.

Nitric oxide-releasing non-steroidal anti-inflammatory drugs: a new generation of antithrombotics?

Long-term use of aspirin as an antithrombotic agent is limited by its toxicity in the gastrointestinal tract. Even very low doses of aspirin can markedly increase the risk of gastrointestinal bleeding and ulceration. Addition of a nitric oxide (NO)-releasing moiety to non-steroidal anti-inflammatory drugs (NSAIDs) has been shown to greatly reduce their ulcerogenic properties as well as their renal toxicity. We proposed that similar derivatisation of aspirin may yield a potent, gastrointestinal-sparing antithrombotic drug. Two prototype compounds (NCX-4215 and NCX-4016; Nicox SA) have been evaluated thus far. Each shows comparable or better anti-aggregatory activity to aspirin while not inducing detectable gastric damage. Current studies are aimed at determining what the optimal balance is between nitric oxide release and inhibition of thromboxane synthesis to achieve good antithrombotic activity with low toxicity. NO-aspirin derivatives appear to offer great potential as gastrointestinal-sparing antithrombotic drugs.

Evaluation of the antitumoral potential of different nitric oxide-donating non-steroidal anti-inflammatory drugs (NO-NSAIDs) on human urological tumor cell lines

Our work aimed at identifying the antitumoral potential of new nitric oxide (NO)-releasing non-steroidal anti-inflammatory drug (NSAID) derivatives on human prostate and bladder carcinoma cell lines. Among all molecules tested, two sulindac derivatives, NCX 1102 ((Z)-5-fluoro-2-methyl-1-[[4-(methylsulfinyl)phenyl] methylene]-1H-indene-3-acetic acid 4-(nitrooxy)butyl ester) and NCX 1105 ((Z)-5-fluoro-2-methyl-1-[[4-(methylsulfinyl)phenyl] methylene]-1H-indene-3-acetic acid 6-(nitrooxymethyl)-2-methylpyrydyl ester hydrochloride), were the most cytotoxic compounds. In contrast to its parent molecule sulindac, cell cycle analysis showed that NCX 1102 led to cell accumulation in the G2-M transition stage in all cell lines, and induced apoptosis in five out of the six cell lines. Thus, NO-NSAIDs may be useful for the elaboration of new therapeutic strategies in the management of bladder and prostate cancer.

Nitrosulindac (NCX 1102): a new nitric oxide-donating non-steroidal anti-inflammatory drug (NO-NSAID), inhibits proliferation and induces apoptosis in human prostatic epithelial cell lines

BACKGROUND

The aim of our study was to explore the anti-tumoral potential of the Nitric Oxide-Donating Non-Steroidal Anti-Inflammatory Drugs (NO-NSAID) NCX1102 (nitrosulindac), on three human prostatic epithelial cell lines at varying degree of transformation (PNT1A, LNCaP, and PC3).

METHODS

Cytotoxicity, anti-proliferative effects, cell-cycle alterations, morphological changes, and apoptosis were investigated after treatment with nitrosulindac in comparison to the native molecule sulindac. Involvement of the polyamine pathway in the action of nitrosulindac was also examined.

RESULTS

Nitrosulindac but not sulindac exerted a cytotoxic effect on all cell lines and an anti-proliferative effect on LNCaP and PC3 cells only. Nitrosulindac differentially altered the cell cycle, induced mitotic arrest and displayed a pro-apoptotic activity in all cell lines. Finally, the polyamine pathway does not seem to be involved in the mechanism of nitrosulindac action.

CONCLUSIONS

Our results demonstrate the anti-proliferative and proapoptotic activity of nitrosulindac on prostate cancer cell lines and suggest its potential interest for new strategies in the management of prostate cancer.

Antiproliferative effect of nitrosulindac (NCX 1102), a new nitric oxide-donating non-steroidal anti-inflammatory drug, on human bladder carcinoma cell lines

Non-steroidal anti-inflammatory drugs (NSAIDs) are potent antitumoral agents but their side effects limit their clinical use. A novel class of drugs, nitric oxide-donating NSAIDs (NO-NSAIDs), was found to be safer and more active than classical NSAIDs. This study explored the effect of the NO-donating sulindac derivative, NCX 1102, on three human urothelial epithelial carcinoma cell lines (T24, 647V, and 1207) and primary cultures of normal urothelial cells. Cytotoxicity, antiproliferative effect, cell cycle alterations, morphological changes, and apoptosis were investigated after treatment with NCX 1102 in comparison with the native molecule. After treatment, there was a cytotoxic effect (with IC50 at 48 h of 23.1 μm on 647V, 19.4 μm on T24, and 14.5 μm on 1207) and an antiproliferative effect on all three cell lines with NCX 1102 but not with sulindac. No effect was detected on normal urothelial cells. Flow cytometric analysis showed a differential NCX 1102-induced accumulation of cells in various phases of the cell cycle, depending on cell line and concentration. NCX 1102 induced an occurrence of multinucleated cells in all cell lines and mitotic arrest in 647V and 1207. NCX 1102-treated T24 and 647V cell lines showed a significant difference of apoptotic cell amount when compared to controls. Our results demonstrated a greater antiproliferative potency of NCX 1102 compared to its parent molecule sulindac, and suggested that this new NO-NSAID may have therapeutic impact in the management of bladder cancer.

Renal papillary necrosis induced by naproxen

A 17-year-old healthy girl was admitted to our hospital with diffuse abdominal pain and decreased oral intake of about 11 days duration. About a week prior to admission, she had taken naproxen, 250 mg four times a day for 4 days. Physical examination was normal except for diffuse abdominal tenderness on deep palpation. Investigations revealed high serum BUN (42 mg/dl) and creatinine (4.0 mg/dl). Serum electrolytes and complement (C3, C4) levels and urinalysis were normal. Antinuclear-antibody and anti-dsDNA were negative. Kidney biopsy revealed renal papillary necrosis, acute tubular necrosis, and focal interstitial nephritis. A diagnosis of nonoliguric acute renal failure due to naproxen nephrotoxicity was made. She received intravenous hydration, and oral steroids, which was gradually discontinued in 3 months. A follow-up at 4 months revealed normal renal function with a serum creatinine of 1.1 mg/dl, BUN 7 mg/dl, and normal urinalysis. The report highlights a need for caution while using naproxen or any other nonsteroidal anti-inflammatory drugs, even for a short duration.

Prescription and non-prescription analgesic use among the US adult population: results from the third National Health and Nutrition Examination Survey (NHANES III)

PURPOSE

To estimate prescription and non-prescription analgesic use in a nationally representative sample of US adults.

METHODS

Data collected during the third National Health and Nutrition Examination Survey (1988-1994), for persons 17 years and older were analyzed (n = 20,050). During the household interview, respondents reported use, in the last month, of prescription and non-prescription analgesics.

RESULTS

An estimated 147 million adults reported monthly analgesic use, Prescription analgesic use was 9% while non-prescription use was 76%. Females were more likely than males to use prescription (11 vs. 7%, p < 0.001) and non-prescription (81 vs. 71%, p < 0.001) analgesics. Across race-ethnicity groups, males (approximately 8%) and females (11-13%) had similar age-adjusted prescription analgesic use. Non-prescription analgesic use was higher among non-Hispanic whites than non-Hispanic blacks and Mexican-Americans for males (76 vs. 53% (p < 0.001) and 59% (p < 0.001), respectively) and females (85 vs. 68% (p < 0.001) and 71% (p < 0.001), respectively). With increasing age, prescription analgesic use increased whereas non-prescription use decreased. Approximately 30% of adults used multiple analgesics during a 1-month period. This was more common among females (35%) than males (25%, p < 0.001) and among younger (17-44 years, 33%) rather than older age groups (45+ years, 26%, p < 0.001).

CONCLUSIONS

Analgesic use among US adults is extremely high, specifically of non-prescription analgesics. Given this, health care providers and consumers should be aware of potential adverse effects and monitor use closely.

Pharmacoeconomics of opioid therapy for chronic non-malignant pain

Chronic non-malignant pain (CNMP) is widely prevalent and associated with significant costs. Costs related to chronic pain include medical services and medications, treatment of medication-related toxicity and work absenteeism. The use of non-narcotic analgesics is associated with inadequate pain-relief for many patients, as well as significant and costly organ toxicity. When used appropriately and judiciously, opioid medications can be a useful addition to the treatment plan for patients with CNMP. Opioids can provide long-term, safe and cost-effective pain relief.

Cyclooxygenase-2 regulates apoptosis in rat epididymis through prostaglandin D2

In previous studies, cyclooxygenase (COX)-1 and COX-2 isozymes have been detected in the rat epididymis. COX-1 mediates electrolyte and fluid secretion induced by a number of peptide hormones, including bradykinin, angiotensin, and endothelin, via local formation of prostaglandin (PG) E2; however, the physiological role of COX-2 remains largely unknown. Marked apoptotic cell death in the rat epididymis following androgen depletion has been reported. Because expression of both COX isozymes is dependent on androgen, we investigated whether these isozymes control apoptosis in the epididymis. Apoptosis was detected in rat epididymal epithelial cells by in situ staining using the TUNEL method and by the presence of internucleosomal DNA fragmentation using capillary electrophoresis with laser-induced fluorescence detection. Specific COX inhibitors were used to delineate the roles of the 2 isozymes. There was no significant apoptotic cell death in normal and specific COX-1 inhibitor (SC-560)-treated epididymal cells. However, application of a specific COX-2 inhibitor (NS-398) induced apoptosis in a dose- and time-dependent manner. A similar apoptotic effect of COX-2 inhibitor was seen in the in vivo study. The drastic DNA fragmentation induced by COX-2 inhibitor could be reversed completely by PGD2 and partially by PGE2. In addition, the protective effect of PGD2 against COX-2 inhibition was significantly blocked by a PGDP-receptor antagonist, BWA868C. These results indicate that the COX-2 products PGD2 and, to a lesser extent, PGE2 control apoptosis in cultured rat epididymal cells in vitro.

Differential effects of the nonsteroidal antiinflammatory drug flurbiprofen and its nitric oxide-releasing derivative, nitroflurbiprofen, on prostaglandin E(2), interleukin-1beta, and nitric oxide synthesis by activated microglia

Increasing experimental, clinical, and epidemiological studies point to the pivotal role of inflammation in the pathogenesis of acute and chronic neurodegenerative diseases and to the protective effects of nonsteroidal antiinflammatory drug (NSAID) therapies. Nonetheless, NSAID long-term therapies are limited by their significant adverse effects on gastrointestinal tract and kidneys. Nitroflurbiprofen (NO-flurbiprofen) belongs to a novel class of antiinflammatory agents obtained by derivatization of conventional NSAIDs with a nitric oxide (NO)-releasing moiety, which strongly reduces their untoward side effects without altering the antiinflammatory effectiveness. The recent evidence of neuroprotective effects of NO-NSAIDs in animal models of chronic brain inflammation prompted us to investigate the activities of NO-flurbiprofen and its parent molecule flurbiprofen on activated rat microglia, the brain resident macrophages. We found that NO-flurbiprofen was as potent as flurbiprofen in preventing prostaglandin E(2) synthesis in lipopolysaccharide-activated microglial cultures. At variance with previous observations on peripheral macrophages is that NO-flurbiprofen did not show any additional capacity to inhibit interleukin-1beta synthesis compared with flurbiprofen. Moreover, NO enhanced the expression of the inducible NO synthase; this effect was most likely attributable to the NO released from the drug, as suggested by experiments performed in the presence of the NO donor Deta-NONOate, which similarly to NO-flurbiprofen is characterised by a slow and long-lasting release. Our findings indicate that NO-NSAIDs may differently affect peripheral and brain macrophages. Given their potential therapeutic role in brain inflammation, further in vivo and in vitro studies are required to understand fully their mechanism of action in the CNS.

Physiological regulation of cyclooxygenase-2 in the kidney

In adult mammalian kidney, cyclooxygenase-2 (COX-2) expression is found in a restricted subpopulation of cells. The two sites of renal COX-2 localization detected in all species to date are the macula densa (MD) and associated cortical thick ascending limb (cTALH) and medullary interstitial cells (MICs). Physiological regulation of COX-2 in these cellular compartments suggests functional roles for eicosanoid products of the enzyme. COX-2 expression increases in high-renin states (salt restriction, angiotensin-converting enzyme inhibition, renovascular hypertension), and selective COX-2 inhibitors significantly decrease plasma renin levels, renal renin activity, and mRNA expression. There is evidence for negative regulation of MD/cTALH COX-2 by angiotensin II and by glucocorticoids and mineralocorticoids. Conversely, nitric oxide generated by neuronal nitric oxide synthase is a positive modulator of COX-2 expression. Decreased extracellular chloride increases COX-2 expression in cultured cTALH, an effect mediated by increased p38 mitogen-activated protein kinase activity, and, in vivo, a sodium-deficient diet increases expression of activated p38 in MD/cTALH. In contrast to COX-2 in MD/cTALH, COX-2 expression increases in MICs in response to a high-salt diet as well as water deprivation. Studies in cultured MICs have confirmed that expression is increased in response to hypertonicity and is mediated, at least in part, by nuclear factor-kappaB activation. COX-2 inhibition leads to apoptosis of MICs in response to hypertonicity in vitro and after water deprivation in vivo. In addition, COX-2 metabolites appear to be important mediators of medullary blood flow and renal salt handling. Therefore, there is increasing evidence that COX-2 is an important physiological mediator of kidney function.

Use of structured self-monitoring in transplant education

A self-assessment instrument for use at home by transplant recipients was developed to help foster partnership between patients and their healthcare provider. Self-monitoring at home has not replaced the need for close follow-up but does allow patients to provide concrete data to their healthcare provider in order to promote earlier detection of and response to adverse events. Patients are taught the essentials of self-monitoring while they are in the hospital for their transplant. Patients who perform routine self-assessment would be able to detect and provide information about problems early in the course of events. Thus, early intervention could potentially decrease the severity of the problem and prevent repeated hospitalizations. The concern that patients would not be able to perform a reliable self-assessment was unfounded; patients exceeded expectations and embraced the opportunity to communicate physical signs and symptoms effectively.

Cyclooxygenase 2 and the kidney

Cyclooxygenase metabolizes arachidonic acid to a family of bioactive fatty acids designated prostaglandins. Two isoforms of cyclooxygenase exist, designated COX1 and COX2. These isoforms are expressed in distinct but important areas of the kidney. COX1 predominates in vascular smooth muscle and collecting ducts, whereas COX2 predominates in the macula densa and nearby cells in the cortical thick ascending limb. COX2 is also highly expressed in medullary interstitial cells. Whereas COX1 expression does not exhibit dynamic regulation, COX2 expression is subject to regulation by several environmental conditions, including salt intake, water intake, medullary tonicity, growth factors, cytokines, and adrenal steroids. Recently, COX2-selective non-steroidal anti-inflammatory drugs have become widely available. Many of the renal effects of non-selective non-steroidal anti-inflammatory drugs (including sodium retention, decreased glomerular filtration rate, and effects on renin-angiotensin levels) appear to be mediated by the inhibition of COX2 rather than COX1. Therefore, in contrast to the gastrointestinal-sparing effects of COX2-selective non-steroidal anti-inflammatory drugs, when considering the kidney, the same caution must be applied when using COX2-selective inhibitors as has been used with traditional non-selective non-steroidal anti-inflammatory drugs.

A center-based approach to a transplant employment program

The return to work after transplantation has been actively discussed in the transplant community for years. However, despite the desire for transplant practitioners to have recipients return to being healthy, contributing members of society as well as return to work, practitioners often passively support the sick role. We discovered that patients who are returning to work after transplantation may have been out of the work force for several years, and require assistance that we as healthcare providers were unable or untrained to provide. An employment specialist was added to the transplant staff and became a vital part of our attempts to create a proactive employment atmosphere and enhance our patients' quality of life. Adding an advocate for employment in our center has also facilitated the shift in our thinking and approach to care from the sick role to one of rehabilitation and from reactive to proactive. This change in attitude has assisted in empowering our recipients to feel as if they can truly resume a normal life.

Dehydration activates an NF-kappaB-driven, COX2-dependent survival mechanism in renal medullary interstitial cells

Renal prostaglandin (PG) synthesis is mediated by cyclooxygenase-1 and -2 (COX1 and COX2). After dehydration, the maintenance of normal renal function becomes particularly dependent upon PG synthesis. The present studies were designed to examine the potential link between medullary COX1 and COX2 expression in hypertonic stress. In response to water deprivation, COX2, but not COX1, mRNA levels increase significantly in the renal medulla, specifically in renal medullary interstitial cells (RMICs). Water deprivation also increases renal NF-kappaB-driven reporter expression in transgenic mice. NF-kappaB activity and COX2 expression could be induced in cultured RMICs with hypertonic sodium chloride and mannitol, but not urea. RMIC COX2 expression was also induced by driving NF-kappaB activation with a constitutively active IkappaB kinase alpha (IKKalpha). Conversely, introduction of a dominant-negative IkappaB mutant reduced COX2 expression after hypertonicity or IKKalpha induction. RMICs failed to survive hypertonicity when COX2 was downregulated using a COX2-selective antisense or blocked with the selective nonsteroidal anti-inflammatory drug (NSAID) SC58236, reagents that did not affect cell survival in isotonic media. In rabbits treated with SC58236, water deprivation induced apoptosis of medullary interstitial cells in the renal papilla. These results demonstrate that water deprivation and hypertonicity activate NF-kappaB. The consequent increase in COX2 expression favors RMIC survival in hypertonic conditions. Inhibition of RMIC COX2 could contribute to NSAID-induced papillary injury.

Regular use of analgesics is a risk factor for renal cell carcinoma

Phenacetin-based analgesics have been linked to the development of renal pelvis cancer and renal cell carcinoma (RCC). The relationship between non-phenacetin types of analgesics and kidney cancer is less clear, although laboratory evidence suggests that these drugs possess carcinogenic potential. A population-based case-control study involving 1204 non-Asian RCC patients aged 25-74 and an equal number of sex-, age- and race-matched neighbourhood controls was conducted in Los Angeles, California, to investigate the relationship between sustained use of analgesics and risk of RCC according to major formulation categories. Detailed information on medical and medication histories, and other lifestyle factors was collected through in-person interviews. Regular use of analgesics was a significant risk factor for RCC in both men and women (odds ratio (OR) = 1.6, 95% confidence interval (CI) = 1.4-1.9 for both sexes combined). Risks were elevated across all four major classes of analgesics (aspirin, non-steroidal anti-inflammatory agents other than aspirin, acetaminophen and phenacetin). Within each class of analgesics, there was statistically significant increasing risk with increasing level of exposure. Although there was some minor variability by major class of formulation, in general individuals in the highest exposure categories exhibited approximately 2.5-fold increase in risk relative to non- or irregular users of analgesics. Subjects who took one regular-strength (i.e. 325 mg) aspirin a day or less for cardiovascular disease prevention were not at an increased risk of RCC (OR = 0.9, 95% CI = 0.6-1.4).

Selective targeting of cyclooxygenase-2 reveals its role in renal medullary interstitial cell survival

Renal medullary interstitial cells (MICs) are a major site of cyclooxygenase (COX)-mediated PG synthesis. These studies examined the role of COX in MIC survival. Immunoblot and nuclease protection demonstrate that cultured MICs constitutively express COX2, with little constitutive COX1 expression. SC-58236, a COX2-selective inhibitor, but not SC-58560, a COX1 inhibitor, preferentially blocks PGE2 synthesis in MICs. Transduction with a COX2 antisense adenovirus reduced MIC COX2 protein expression and also decreased PGE2 production. Antisense downregulation of COX2 was associated with MIC death, whereas a control adenovirus was without effect. Similarly, the COX2-selective inhibitor SC-58236 (30 microM) and several nonselective COX-inhibiting nonsteroidal anti-inflammatory drugs (NSAIDs), including sulindac, ibuprofen, and indomethacin, all caused MIC death. In contrast, SC-58560, a COX1-selective inhibitor, was 100-fold less potent for inducing MIC death than its structural congener SC-58236. NSAID-induced MIC death was associated with DNA laddering and nuclear fragmentation, consistent with apoptosis. These results suggest that COX2 plays an important role in MIC survival. COX2 inhibition may contribute to NSAID-associated injury of the renal medulla.

The renal effects of nonsteroidal anti-inflammatory drugs in older people: findings from the Established Populations for Epidemiologic Studies of the Elderly

OBJECTIVE

To determine whether older people who use nonsteroidal anti-inflammatory agents (NSAIDs) have increased levels of blood urea nitrogen (BUN), serum creatinine, and BUN:serum creatinine ratio.

DESIGN

Cross-sectional, secondary data analysis.

SETTING

Older people living in the communities of East Boston, MA, New Haven, CT, and Washington and Iowa Counties, Iowa.

PARTICIPANTS

A total of 4099 people aged 70 years or older who were participants in the National Institute on Aging's Established Populations for Epidemiologic Studies of the Elderly project, had survived to the 6-year follow-up interview and had consented to the blood drawing.

MEASUREMENTS

We assessed use of the NSAIDs at the 3- and 6-year interviews through a drug inventory and visual review of medication containers. Markers of renal function assessed through analysis of blood samples drawn at the time of the interview included BUN and creatinine.

RESULTS

Fifteen percent of the cohort reported use of NSAIDs during the 2 weeks preceding the 6-year interview. Controlling for age, sex, and a range of potential confounding variables, NSAID users had significant prevalence odds ratios of 1.9 (95% confidence interval (CI), 1.5-2.3) for being in the highest quartile of BUN (>23), 1.3 (CI 1.1-1.7) for the highest quartile of serum creatinine (> or =1.4), and 1.7 (CI 1.4-2.1) for the highest quartile of the BUN:creatinine ratio (> or = 19.4). Chronic NSAID users (those who reported NSAID use at both the 3-year and 6-year interviews) accounted for the increased risk of high serum creatinine levels.

CONCLUSION

Community-dwelling older people who use NSAIDs tend to have higher levels of common laboratory markers of renal dysfunction. This hypothesis requires further testing in prospective cohort studies designed a priori to evaluate these issues.

In vivo regulation of MAP kinases in Ratus norvegicus renal papilla by water loading and restriction

In cultured renal cells, hypertonicity activates multiple mitogen-activated protein kinases (MAPKs) and enhances the expression of heat shock proteins (HSPs). In rats, 24 h water restriction increased mean urinary osmolality (Uosm) from 2, 179+/-153 mOsm/kg to 2,944+/-294 mOsm/kg (P < 0.001) and was associated with significant (P < 0.05) increases in the papillary activity of c-Jun NH2-terminal protein kinase (JNK) by 22%, extracellular signal-regulated protein kinase (ERK) by 49%, and p38 MAPK by 15%. Conversely, 24 h of water-loading (Uosm 473+/-33 mOsm/kg) caused suppression of JNK activity by 43% (P < 0.001), ERK by 39% (P < 0.05), and p38 MAPK by 26% (P < 0.05). No such modulation was observed in the isotonic cortex. c-Jun phosphorylation was decreased in papilla from water-loaded rats by 45% versus controls. Expression of Hsp 110, inducible Hsp 70, and Hsp 25 was greater in the hyperosmotic papilla than the isosmotic cortex but was not affected by the animal's hydration state. In cultured inner medullary collecting duct cells, HSP expression was maximal at 500 mOsm/kg, while activation of JNK continued to increase. We conclude that under basal conditions of hydration, these HSPs are maximally expressed in the hypertonic inner medulla, while the activation of all three members of the MAPK family approaches but is not maximal.

Nonsteroidal anti-inflammatory drug use in adolescence

Nonsteroidal anti-inflammatory drugs (NSAIDs) have been recently released as over-the-counter drugs making them more widely available to the general public. We present five cases of adolescents with complications, including acute and chronic renal failure, related to the use of NSAIDs. Risk factors for NSAID nephrotoxicity include chronic illness, dehydration, ethanol and use of other medications. Adolescents should be educated about the risks and prevention of NSAID toxicity.

A safety assessment of fixed combinations of acetaminophen and acetylsalicylic acid, coformulated with caffeine

Overuse and abuse of phenacetin-containing mixed analgesics has contributed to end-stage renal disease. Combination analgesics, especially those coformulated with caffeine, have been implicated as imparting a greater risk of analgesic-associated nephropathy (AAN) than single or coformulated analgesics without caffeine. This has led to a recommendation that the sale of "two plus caffeine" analgesic mixtures be reclassified from over-the-counter to prescription only availability. There is a rational basis for coformulating acetylsalicylic acid (ASA) and acetaminophen (paracetamol) as this reduces the dose of each, without altering efficacy. The coformulation of caffeine with these analgesics has a significant adjuvant effect and increases analgesic efficacy 1.4-1.6-fold. Currently available animal and human data do not support the notion that the nephrotoxic risk from coformulated ASA and acetaminophen is higher than the risk from either ASA or acetaminophen alone, in equivalent analgesic doses. There are no epidemiological data that implicate caffeine in AAN, and only limited evidence that links excessive acetaminophen usage to renal disease. There is no evidence that caffeine increases analgesics papillotoxicity directly. The presence of caffeine in mixtures of analgesics are no more addictive than other sources of caffeine. There is no evidence to suggest that adding caffeine to analgesic mixtures enhances the potential for promoting analgesic misuse in the general population. Thus distinct therapeutic benefits of ASA, acetaminophen and caffeine appear to outweigh any known risk. It is doubtful if preventing the availability of these products will significantly affect the role of analgesic abuse/overuse in end-stage renal disease. Better risk management would come from a focused educational program, developed in a close collaboration between industry, healthcare professionals and consumer organizations, such a program must warn against the potential dangers of analgesic and non-steroidal anti-inflammatory drug misuse.

Interspecies differences in renal localization of cyclooxygenase isoforms: implications in nonsteroidal antiinflammatory drug-related nephrotoxicity

Cyclooxygenase (COX) exists in 2 related but unique isoforms: one is constitutive (COX-1) and functions in normal cell physiology, and the other is inducible (COX-2) and is expressed in response to inflammatory stimuli. Nonsteroidal antiinflammatory drugs (NSAIDs) cause renal toxicity following inhibition of renal cyclooxygenases. Humans and animals exhibit differences in susceptibility to NSAID-related renal toxicity, which may be associated with differences in expression of 1 or both isoforms of COX in the kidney. In this study, we evaluated COX-1 and COX-2 expression in the kidneys of mixed-breed dogs, Sprague-Dawley rats, cynomolgus monkeys, and humans. In addition, the effect of volume depletion on renal COX expression was investigated in rats, dogs, and monkeys. COX expression was evaluated using 1 or more of the following procedures: reverse transcriptase polymerase chain reaction, in situ hybridization, and immunohistochemistry. We demonstrated that both COX isoforms are expressed in the kidneys of all species examined, with differences in the localization and level of basal expression. COX-1 is expressed at high levels in the collecting ducts and renal vasculature of all species and in a small number of papillary interstitial cells in rats, monkeys, and humans. Basal levels of COX-2 are present in the maculae densa, thick ascending limbs, and papillary interstitial cells in rats and dogs and in glomerular podocytes and small blood vessels in monkeys and humans. COX-2 expression is markedly increased in volume-depleted rats and dogs but not monkeys. These results indicate that significant interspecies differences exist in the presence and distribution of COX isoforms, which may help explain the difference in species susceptibility to NSAID-related renal toxicity.

A review of epidemiologic studies of nonnarcotic analgesics and chronic renal disease

The relationship of long-term and heavy exposure of nonnarcotic analgesics to the risk of chronic renal disease (CRD) has been the object of intensive clinical, pharmacologic, toxicologic, and epidemiologic research for 4 decades. The clinical evidence of an increased risk has been suggestive but inconclusive. The experimental evidence in animal models has been inconsistent, and in any case it cannot be generalized to humans. The epidemiologic evidence has been unsatisfactory for the most part: most of the early studies had severe methodologic limitations; moreover, they related mainly to phenacetin-containing drugs and did not have useful information on other analgesics. Since 1980, 9 analytical epidemiologic studies have attempted to confirm that a causal relationship exists between phenacetin or other analgesics and CRD. In the aggregate, despite methodologic flaws, this work suggests that excessive use of phenacetin-containing analgesics probably causes renal papillary necrosis and interstitial nephritis. In contrast, there is no convincing epidemiologic evidence that nonphenacetin-containing analgesics (including acetaminophen, aspirin, and mixtures of these two compounds) or that nonsteroidal antiinflammatory drugs cause CRD. Moreover, the nature of dose-response relationships, the types of renal disease possibly caused by analgesics, and the cofactors that might be related both to analgesic use and to the development of CRD in humans are still uncertain, and the pathologic mechanisms of analgesic-induced CRD in humans remain unclear. It may take many years before all the outstanding issues are settled. Until they are, as a matter of good clinical judgment it would be prudent to consider all analgesics as potentially nephrotoxic and, as much as possible, to avoid excessive, protracted use.