Effects of sulindac and naproxen in patients with chronic glomerular disease

Comparative Effects of Metamizole (Dipyrone) and Naproxen on Renal Function and Prostacyclin Synthesis in Salt-Depleted Healthy Subjects - A Randomized Controlled Parallel Group Study

Aim: The objective was to investigate the effect of metamizole on renal function in healthy, salt-depleted volunteers. In addition, the pharmacokinetics of the four major metamizole metabolites were assessed and correlated with the pharmacodynamic effect using urinary excretion of the prostacyclin metabolite 6-keto-prostaglandin F1α. Methods: Fifteen healthy male volunteers were studied in an open-label randomized controlled parallel group study. Eight subjects received oral metamizole 1,000 mg three times daily and seven subjects naproxen 500 mg twice daily for 7 days. All subjects were on a low sodium diet (50 mmol sodium/day) starting 1 week prior to dosing until the end of the study. Glomerular filtration rate was measured using inulin clearance. Urinary excretion of sodium, potassium, creatinine, 6-keto-prostaglandin F1α, and pharmacokinetic parameters of naproxen and metamizole metabolites were assessed after the first and after repeated dosing. Results: In moderately sodium-depleted healthy subjects, single or multiple dose metamizole or naproxen did not significantly affect inulin and creatinine clearance or sodium excretion. Both drugs reduced renal 6-keto-prostaglandin F1α excretion after single and repeated dosing. The effect started 2 h after intake, persisted for the entire dosing period and correlated with the concentration-profile of naproxen and the active metamizole metabolite 4-methylaminoantipyrine (4-MAA). PKPD modelling indicated less potent COX-inhibition by 4-MAA (EC₅₀ 0.69 ± 0.27 µM) compared with naproxen (EC₅₀ 0.034 ± 0.033 µM). Conclusions: Short term treatment with metamizole or naproxen has no significant effect on renal function in moderately sodium depleted healthy subjects. At clinically relevant doses, 4-MAA and naproxen both inhibit COX-mediated renal prostacyclin synthesis.

Effects of indomethacin on renal function in normotensive patients with chronic glomerulonephritis with preserved renal function

Thirteen normotensive patients with biopsy verified chronic glomerulonephritis (GN) with preserved renal function and 12 healthy control subjects (CS) were studied before and during prostaglandin synthesis inhibition by indomethacin. Glomerular filtration rate (GFR), renal plasma flow (RPF), urinary output (V), sodium excretion (UNa V), fractional lithium excretion (FELi), plasma levels of angiotensin II (Ang II), aldosterone (Aldo), atrial natiuretic peptide (ANP), arginine vasopressin (AVP) and endothelin (ir-ET) and urinary excretion rates of PGE2, mean blood pressure (MBP) and heart rate (HB) were determined on two separate occasions at least 7 days apart. During basal conditions without indomethacin administration no significant differences were found between the two groups. Indomethacin administration (100 mg 12 h and 1 h before clearance investigations) resulted in significant and almost identical decreases in GFR, RPF, V, UNa V, FELi and HR and increases in MBP in both the GN group and the CS group. It is concluded that normotensive patients with a biopsy verified chronic glomerulonephritis but with preserved renal function and without nephrotic syndrome have no increased risk of acute deterioration of renal function during administration of a non-steroidal anti-inflammatory drug compared with healthy control subjects.

Clinical and prognostic associations based on serum antinuclear antibodies in Japanese patients with systemic sclerosis

OBJECTIVE

To clarify the clinical features and prognosis of systemic sclerosis (SSc) based on serum antinuclear antibodies (ANA).

METHODS

We studied 275 consecutive Japanese patients newly diagnosed as having SSc, who were first evaluated during the period 1971-1990. Eight SSc-related ANA were identified using indirect immunofluorescence, double immunodiffusion, or immunoprecipitation assays. Clinical and prognostic features were retrospectively analyzed in patient groups, categorized by their serum ANA.

RESULTS

Cumulative survival rates at 10 years after diagnosis of SSc were 93% in patients with anticentromere antibodies (ACA), 72% in those with anti-U1 RNP, 66% in those with anti-DNA topoisomerase I (anti-topo I), and 30% in those with anti-RNA polymerases I, II, and III (anti-RNAP). Major organ involvement linked to cause of death included biliary cirrhosis in patients with ACA, isolated pulmonary arterial hypertension and cerebral hemorrhage in those with anti-U1 RNP, pulmonary interstitial fibrosis in those with anti-topo I, and cardiac and renal involvement in those with anti-RNAP.

CONCLUSION

Determinations of serum ANA in SSc patients are useful in predicting organ involvement and long-term outcome.

Effects of sulindac and naproxen on prostaglandin excretion in patients with impaired renal function and rheumatoid arthritis

PURPOSE

The purpose of the current investigation was to study the influence of sulindac and naproxen on renal function and urinary excretion of the stable hydration product of prostacyclin, 6-keto-PGF1 alpha, in patients with arthritis and impaired renal function.

PATIENTS AND METHODS

In a placebo-controlled, double-blind, cross-over design, the effects of 7 days of oral sulindac 200 mg twice a day were compared with naproxen 500 mg in the morning and 250 mg in the evening in 10 patients with polyarthritis and stable impaired renal function. Inulin and para-amino-hippurate sodium were used to calculate glomerular filtration rate and renal plasma flow. The excretion rate of 6-keto-PGF1 alpha was measured in urine collected overnight. After patients ingested drugs in the morning, urine was collected in fractions by spontaneous voiding. Venous blood samples were drawn repeatedly for assay of electrolytes, creatinine, proteins, hormones, and drugs. Grip strength and Ritchie articular index were recorded as indicators of symptomatic antiarthritic effectiveness.

RESULTS

Naproxen decreased urine levels of 6-keto PGF1 alpha by 59% (p less than 0.01). Sulindac had no effect on renal prostaglandin excretion. Naproxen reduced the glomerular filtration rate and renal plasma flow by 18% (p less than 0.05) and 13% (p less than 0.05), respectively, while no significant change was observed during the sulindac treatment periods. Serum levels of creatinine and complement factor D were unaffected by either drug. Plasma renin activity decreased during naproxen and sulindac treatments by 38% (p less than 0.05) and 22% (p less than 0.05). No significant change in plasma aldosterone was observed during the two drug treatments, but urinary aldosterone declined significantly (p less than 0.05) by 34% with naproxen. Albuminuria decreased (p less than 0.05) during both naproxen (41%) and sulindac treatment (72%), while the albumin/creatinine clearance ratio decreased by 59% (p less than 0.05) only during treatment with sulindac. N-acetyl-beta-D-glucosaminidase in urine was not changed by either drug. Sulindac and naproxen had no discernible effects on base excess, excretion of water, sodium, or potassium, or on osmolal clearance. However, serum potassium increased slightly but significantly (p less than 0.01) during treatment with naproxen. Sulindac sulfide, the active metabolite of sulindac, could not be traced in the urine from any of the patients. Mean arterial blood pressure declined significantly (p less than 0.05) during sulindac treatment but did not change during treatment with naproxen. Both drugs produced equal clinical improvement as measured by grip strength and the Ritchie articular index.

CONCLUSION

The results suggest that when sulindac and naproxen are given in clinical equipotent doses to patients with impaired renal function, sulindac does not affect renal prostaglandin synthesis or renal function, whereas naproxen induces suppression of renal prostaglandin synthesis and a further decrease in renal function.

Naproxen. A reappraisal of its pharmacology, and therapeutic use in rheumatic diseases and pain states

Naproxen is a nonsteroidal anti-inflammatory drug (NSAID) advocated for use in painful and inflammatory rheumatic and certain nonrheumatic conditions. It may be administered orally or rectally using a convenient once or twice daily regimen. Dosage adjustments are not usually required in the elderly or those with mild renal or hepatic impairment although it is probably prudent to start treatment at a low dosage and titrate upwards in such groups of patients. Numerous clinical trials have confirmed that the analgesic and anti-inflammatory efficacy of naproxen is equivalent to that of the many newer and established NSAIDs with which it has been compared. The drug is effective in many rheumatic diseases such as rheumatoid arthritis, osteoarthritis, ankylosing spondylitis and nonarticular rheumatism, in acute traumatic injury, and in the treatment of and prophylaxis against acute pain such as migraine, tension headache, postoperative pain, postpartum pain and pain associated with a variety of gynaecological procedures. Naproxen is also effective in treating the pain and associated symptoms of primary or secondary dysmenorrhoea, and decreases excessive blood loss in patients with menorrhagia. The adverse effect profile of naproxen is well established, particularly compared with that of many newer NSAIDs, and the drug is well tolerated. Thus, the efficacy and tolerability of naproxen have been clearly established over many years of clinical use, and it can therefore be considered as a first-line treatment for rheumatic diseases and various pain states.