Acupoint Catgut Embedding With Laser Acupuncture for Weight Loss in Adults With Obesity

BackgroundAcupoint catgut embedding and laser acupuncture have each accumulated clinical evidenceas treatments for obesity in adults, but three gaps remain. First, the two have not beenevaluated in combination. Second, few published trials measure anthropometric,biochemical, and blood pressure outcomes together. Third, most existing trials are small,and systematic reviews have repeatedly noted limitations in blinding and sham control.Supporting literature is listed under Citations.Rationale for the designAcupoint embedding delivers sustained mechanical stimulation as the suture degrades overseveral weeks, whereas laser acupuncture delivers an energy input at the time of eachsession. The two therefore differ in mechanism and in time course. By giving identicalacupoint embedding to both groups and varying only whether the laser emits energy, thetrial estimates the incremental effect attributable to laser acupuncture rather than thecombined effect of the two therapies.MaskingMasking is implemented at four levels. Participants are masked because 810 nm light isoutside the visible range and safety goggles are worn during treatment. The treatingphysician is masked because the manufacturer supplies dedicated sham pens whose housing,red indicator light, and operating sound are identical to the active pens but whose lasermodule is disconnected, giving an actual output of 0 milliwatts. The research assistantswho perform all measurements take no part in treatment and are not informed ofallocation. The statistician works from coded group labels until unmasking. Active andsham pens are managed by a study coordinator who takes no part in treatment; pens carryonly a serial number with no active or sham marking, and the code list is held sealed ina safe in the principal investigator's office, to be opened only for a serious adverseevent or a genuine medical emergency.RandomizationA permuted block randomization sequence, with block size randomly set to 4 or 6 and anallocation ratio of 1:1, is generated in advance with the R blockrand package by anindependent statistician who takes no part in enrollment or treatment, stratified by sexand by body mass index category (less than 30 versus 30 kg/m^2 or greater). Allocation isimplemented using sequentially numbered opaque sealed envelopes.Statistical analysisThe primary analysis follows the intention‐to‐treat principle using a linearmixed‐effects model containing group, time, the group‐by‐time interaction, the baselinevalue, the stratification factors, and a random participant effect. The Week 12group‐by‐time contrast is reported as a least‐squares mean difference with a 95 percentconfidence interval. Missing data are handled by the model under a missing‐at‐randomassumption, with last‐observation‐carried‐forward and multiple imputation (20imputations) as sensitivity analyses. A per‐protocol analysis, defined as completion ofat least 80 percent of treatment sessions with no major protocol violation, is a furthersensitivity analysis. Secondary anthropometric outcomes use the same mixed‐modelstructure. Biochemical outcomes use mixed models or analysis of covariance with thebaseline value as covariate, with log transformation for skewed variables such astriglycerides and the homeostatic model assessment of insulin resistance. Blood pressureis analyzed by analysis of covariance at Week 12. Secondary outcomes are prespecified butare not adjusted for multiplicity; effect sizes and 95 percent confidence intervals arereported for each. Prespecified subgroup analyses are by sex and by body mass indexcategory. The significance level is two‐sided alpha of 0.05.Sample sizeThe sample size is based on the primary outcome of weight change. With a standardizedeffect size of 0.67, two‐sided alpha of 0.05, and 80 percent power, 35 participants pergroup are required. Allowing for 15 percent attrition and providing power for thesecondary metabolic outcomes, the enrollment target is 60 participants per group, 120 intotal.Safety monitoringExpected reactions to acupoint embedding include transient pain, bruising, or a mildnodule at the insertion site, usually resolving within days to two weeks. Less commonevents include local infection, allergic reaction, or suture extrusion. Reported adverseevents from laser acupuncture are limited to transient warmth or erythema. Any seriousadverse event, defined as one causing hospitalization, a life‐threatening event,permanent disability, or death, is reported to the ethics committee and the principalinvestigator within 24 hours. Given the anticipated risk profile of the interventions, anindependent safety monitor rather than a data and safety monitoring board overseessafety. The monitor reviews a safety summary monthly, the study coordinator compiles asafety data summary for the monitor every 3 months, and a formal interim safety review isconducted when enrollment reaches 60 participants.Quality controlPhysicians performing embedding and laser treatment must hold a license in Chinesemedicine, have at least 2 years of clinical embedding experience, and complete laseracupuncture operator training, together with standard operating procedure training andsimulated cases before enrollment begins. Laser output is verified monthly with anoptical power meter, and a deviation of more than 10 percent triggers recalibration; thesham pens are confirmed to output 0 milliwatts. Measurement assistants completestandardized training and must reach an inter‐rater intraclass correlation coefficientabove 0.90.