Extended-interval Dosing Regimen Of Gonadotropin Releasing Hormone Agonist In The Treatment Of Endometriosis And Adenomyosis: A Mata Analysis

Objective To assess the efficacy of an extended-interval dosing regimen of gonadotropin releasing hormone agonist in treatment of endometriosis and adenomyosis.Methods The Cochrane systematic review method was used to evaluate the Ran- domized Controlled Trials (RCTs)of an extended-interval dosing regimen of gonadotropin releasing hormone agonist in treatment of endometriosis and adenomyosis.The searching strategy included:MEDLINE(1950 to 04.2011),EMBASE(1980 to 04.2011),The Cochrane Central Register of Controlled Trials,Current Controlled Trials,The National Research Register,Clinical Trials,CBM(1978-2011.04),VIP(1989 to 2011.04),CNKI(1996 to 2011.04).We also handsearched some related journals.The search was conducted in 04.2011.Three reviewers evaluated quality of studies,meta-analysis were performed for combine the results of homogeneity studies.The RevMan 5.0 soft ware was used for statistical analysis.Results We recruited 4 studies including 204 patients.All included studies were gonadotropin releasing hormone agonist used for endometriosis and adenomyosis. Patients in the control group received a conventional regimen ( triptorelin 3.75mg 1 injection every 4 weeks for a total of 6 doses).The patients in the experimental group received a 4 dose regimen (triptorelin 3.75mg by intramuscular injection every 6 weeks for a total of 4 doses ).All the included studies were inadquate in reporting randomization,concealment of allocation and blinding.Meta-analysis based on included studies showed that there were no significant difference between the traditional dosing and the extended-interval dosing for the outcome of the reliving rate of dysmenorrhea or reduction of uterine volume .One of these included studies had analyzed the volume of the lesion. It showed that the volume of the lesion reduced≥1/3 in 82% patients treated with both the new regimen and the convention regimen after 6 months,the former was 81%(13/16) and the later was 82%(18/22).There was not statistically significant(P >0.05) in the two groups . The level of luteinizing hormone (LH), follicle stimulating hormone (FSH) and estradiol (E₂) in the two groups were decreased significantly.The E₂ levels were reduced to the postmenopausal leved.The hormone profile of the experimental group was similar to that of the control group(p>0.05) except the E₂ level behind 24 weeks .After 24 weeks of the tratment,the levels of E₂ in the new group are higher than that in the troditional group.Three of four included studies describing the side effects show that no patients in both the two groups had experienced climacteric symptoms such as hot flushes, sweats, and vaginal dryness by the mid-point of the treatment period (3 months).During the second half of the treatment period,the side effects occured with a varying degrees in the two groups.Nevertheless,for both groups,these side effects were mild and tolerated.A comparison of the recurrence rates of dismenorrhoea in the 3 included studies show that there was not statistically significant between the two groups.Conclusion The limited evidence showed that there were no significant difference between the extended-interval dosing regimen of gonadotropin releasing hormone agonist and the troditional regimen for the outcomes of the reliving rate of dysmeno- rrhea , reduction of uterine volume, the level of hormone or disease recurrence , but the cost of the treatment can be ruduced remarkbly.As the included studies were in the high probability of both slection bias and measuerment bias,it yet do not draw a firm conclusion for the efficacy and safety of the extended-interval dosing regimen of gon- adotropin releasing hormone agonist in the treatment of endometriosis and adenomyo- sis.Our results suggest that further and larger scale randomized controlledtrials on the use of extended-interval dosing regimen of gonadotropin releasing hormone agonist for endometriosis and adenomyosis are needed.