A guide to GRADE guidelines for the readers of JTH

More than 70 organizations worldwide have adopted the GRADE methodology for guideline development. The ninth iteration of the American Collage of Chest Physicians guidelines (AT9) adopted structural and policy changes that resulted in a greater adherence to GRADE guidance than previous iterations. The most important of these changes include minimizing the impact of financial and intellectual conflict of interest, increasing the rigor of evidence evaluation, acknowledging uncertainty in estimates of typical values and preferences, and awareness of the large variability in values and preferences. One of the consequences of the greater adherence to GRADE methodology is an increase in weak vs. strong recommendations in AT9. The result of the GRADE process highlights the desirability of higher-quality evidence both regarding the outcomes of alternative management strategies and regarding the distribution of values and preferences in patients considering those alternatives. It also encourages shared decision making in encounters between physicians and patients. Although some physicians might find the uncertainty underlying medical practice discouraging or unsettling, relative to denying or obscuring the uncertainty, acknowledging and addressing the uncertainty will lead to more credible, realistic, and useful recommendations.

2000 Wolfe Award. Sumatriptan for the range of headaches in migraine sufferers: results of the Spectrum Study

BACKGROUND

Migraineurs experience a spectrum of headaches: migraine, migrainous, and episodic tension-type as defined by the International Headache Society (IHS).

OBJECTIVE

To evaluate the effectiveness of sumatriptan, 50-mg tablets, in treating the spectrum of headaches in IHS-diagnosed migraineurs.

DESIGN/METHODS

Migraineurs with severe disability (Headache Impact Questionnaire score 250 or greater) were enrolled in a randomized, double-blind, placebo-controlled, crossover study. Patients treated up to 10 headaches with sumatriptan, 50 mg, or placebo (4:1). Headache features, recorded prior to treatment, were used to classify each headache using IHS criteria. Headache response (moderate or severe pain reduced to mild or no pain) and pain-free response were recorded at 2 and 4 hours postdose (primary endpoint). Because patients treated multiple attacks, statistical methods controlling for within-subject correlation were used.

RESULTS

Two hundred forty-nine migraineurs treated 1576 moderate or severe headaches: migraine (n = 1110), migrainous (n = 103), and tension-type (n = 363). Sumatriptan was superior to placebo for headache response 4 hours postdose (primary endpoint) across all headache types (migraine, 66% versus 48%; P<.001; migrainous, 71% versus 39%; P<.01; tension-type, 78% versus 50%, P<.001). Sumatriptan was also superior to placebo for pain-free response 4 hours postdose for migraine (41% versus 24%, P<.001) and tension-type headaches (56% versus 36%, P =.001). Sumatriptan provided superior pain-free response 2 hours postdose for migraine (18% versus 7%, P<.0001) and tension-type headache (28% versus 14%, P =.0005) compared with placebo.

CONCLUSION

Sumatriptan, 50-mg tablets, are effective for the full spectrum of headaches experienced by patients with disabling migraine due to a sumatriptan-responsive mechanism.

Treatment of mild headache in disabled migraine sufferers: results of the Spectrum Study

OBJECTIVE

To evaluate the effectiveness of sumatriptan, 50-mg tablets, versus placebo for early intervention while head pain was mild in patients with disabling migraine.

METHODS

A post hoc analysis was performed in a subgroup of patients from a large, randomized, placebo-controlled study of patients with disabling headache who treated while pain was mild. Pain-free response 2 and 4 hours postdose, headache recurrence, and safety were examined. Significance tests were performed only for the first-treated attacks.

RESULTS

Twenty-six patients with disabling headache treated 46 mild and 166 moderate or severe headaches. For the first-treated headaches while pain was mild, pain-free rates were significantly higher for sumatriptan than placebo 4 hours postdose (78% versus 0%, P =.02), but not 2 hours postdose (52% versus 0%, P =.22). Across all headaches treated while pain was mild, pain-free responses were higher for sumatriptan than placebo 4 hours (85% versus 17%) and 2 hours (50% versus 0%) postdose compared with placebo. When the same patients treated headaches while pain was moderate or severe, pain-free rates were lower than that reported for treatment during mild pain. There was a trend toward lower headache recurrence in headaches treated while pain was mild compared with moderate or severe pain (13% versus 18%). No drug-related adverse events were reported in the headaches treated while pain was mild.

CONCLUSIONS

Patients with disabling migraine may benefit from early intervention with sumatriptan, 50 mg, while pain is mild.

Tolerability of sumatriptan: clinical trials and post-marketing experience

Through December 1998, sumatriptan had been used to treat more than 236 million migraine attacks world-wide. In clinical trials alone, more than 88000 migraine patients had treated more than 300000 migraine attacks with sumatriptan, and 2000 normal healthy volunteers had been exposed to the drug. This paper describes the safety and tolerability profile of sumatriptan in three sections: adverse events reported in clinical trials, special issues, and spontaneous post-marketing reports of adverse reactions. Data from the extensive clinical trials programme coupled with information from nearly 10 years of experience in clinical practice demonstrate that sumatriptan is generally well-tolerated, with an acceptable benefit-risk ratio when used properly. Significant cardiovascular and cerebrovascular events are rare but have been observed. This fact highlights the need for careful patient selection and vigilant adherence to the prescribing recommendations for sumatriptan. The wealth of clinical trials and post-marketing information for sumatriptan may be useful in guiding prescribing decisions for members of this class of drugs.

Responsiveness of non-IHS migraine and tension-type headache to sumatriptan

In a long-term efficacy and safety study, 424 patients were treated with sumatriptan (6 mg sc) for 1,904 migraine attacks. The patients were diagnosed with migraine based on IHS criteria but individual migraine attacks treated in the study were physician diagnosed; not necessarily required to meet IHS criteria. A re-analysis of the treatment response to open label sumatriptan (6 mg sc) indicated that 43 patients had treated at least one migraine that fulfilled IHS criteria for tension-type headache. Analysis of this population revealed they treated 232 headaches. Of these headaches, 114 were classified per IHS criteria as migraine; 76 as tension-type; and 42 as non-IHS migraine (not classifiable as IHS migraine or IHS tension-type headache). Of the 114 migraines, a positive response to sumatriptan occurred in 109 (96%) cases; of the 76 tension-types, 73 responded to sumatriptan (97%); of the 42 non-IHS migraine, 40 (95%) responded to sumatriptan. An equivalent response to sumatriptan among three diagnostic groups of headache supports the concept of a common biologic mechanism involving 5HT1 receptors that spans a range of clinical presentations.

Comparative clinical trial of imipenem-cilastatin (N-formimidoyl-thienamycin-dehydropeptidase inhibitor) and cefazolin

One hundred and eighty-six patients were randomized to receive either imipenem-cilastatin (94 patients) or cefazolin (92 patients). Imipenem-cilastatin (250 mg 6 hourly iv) or cefazolin (1000 mg 6 hourly iv) were given for 5 to 14 days. An assessment of efficacy could be made in 141 patients, 72 of whom received imipenem-cilastatin and 69 of whom received cefazolin. Reasons for exclusion included failure to isolate a causative organism (20 patients), less than 5 days of treatment (16 patients), inadequate follow up or culture (5 patients), concomitant administration of another antibiotic (1 patient), and resistance to the study drug (3 patients, all of whom were in the cefazolin group). No isolates resistant to imipenem were found. Sites of infection included skin and soft tissue (91 patients), lower respiratory tract (21 patients), urinary tract (16 patients), bone and joint (8 patients), primary bacteraemia (4 patients) and miscellaneous other sites (1 patient). Bacteria isolated included Staphylococcus aureus (65 patients), group A streptococcus (42 patients), Escherichia coli (17 patients), other Gram-negative bacilli (37 patients), anaerobic bacteria (34 patients) and other bacteria. Imipenem was more active than cephalothin in vitro against pathogenic bacteria isolated from evaluable patients. Cure or improvement was seen in 68 of the 72 imipenem-cilastatin patients (94%) and in 68 of the 69 cefazolin patients (99%). Relatively few abnormal laboratory tests and adverse experiences were noted, and there were no differences in this between the two treatment groups. We concluded that imipenem-cilastatin is safe at the dose used. It is as effective as cefazolin in mild to moderate infections caused by common pathogens.(ABSTRACT TRUNCATED AT 250 WORDS)