FDA clears Trigeminal nerve stimulation (TNS) as ADHD treatment

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Although stim­u­lant med­ica­tions are gen­er­al­ly con­sid­ered to be a safe and effec­tive treat­ment for ADHD, not all chil­dren ben­e­fit from this approach. Many par­ents are reluc­tant to begin their child on med­ica­tion and some chil­dren expe­ri­ence unac­cept­able side affects.

For these rea­sons, devel­op­ing safe and effec­tive alter­na­tive treat­ments for ADHD remains a pri­or­i­ty. Trigem­i­nal nerve stim­u­la­tion (TNS) is an alter­na­tive approach that was recent­ly test­ed in a dou­ble-blind, sham-con­trolled study.

The Study:

TNS is a non­in­va­sive, min­in­mal-risk neu­ro­mod­u­la­tion pro­ce­dure that has been pre­vi­ous­ly approved in Cana­da and Europe to treat adults with med­ica­tion-resis­tant depres­sion and epilepsy.

The trigem­i­nal nerve con­veys sen­so­ry inputs to regions of the brain that under­ly the main­te­nance of atten­tion. Indi­vid­u­als under­go­ing TNS treat­ment wear a small stim­u­la­tor dur­ing sleep that emits a low-lev­el cur­rent to stim­u­late the trigem­i­nal nerve. This is hypoth­e­sized to increase acti­va­tion in par­tic­u­lar brain regions relat­ed to ADHD symp­toms such that those symp­toms are reduced.

TNS was test­ed in this study with 62 8- to-12-year old youth diag­nosed with ADHD; rough­ly two-thirds were male and none were on med­ica­tion dur­ing the study.

Par­tic­i­pants were ran­dom­ly assigned to receive 4 weeks of active TNS, or a sham treat­ment, dur­ing sleep. Chil­dren in the sham treat­ment wore the same device dur­ing sleep but their trigem­i­nal nerve was not stimulated.

The study was intro­duced to chil­dren and par­ents so that the like­li­hood of being able to know for cer­tain whether active or sham treat­ment was being pro­vid­ed was min­i­mized. And, in fact, data col­lect­ed dur­ing the study indi­cat­ed that par­tic­i­pants were not bet­ter than chance at know­ing which group they were in.

The pri­ma­ry out­come mea­sure was a clin­i­cian-com­plet­ed rat­ing of ADHD symp­toms; the rat­ings were made based on inter­view­ing par­ents and all oth­er avail­able clin­i­cal infor­ma­tion. Rat­ings were com­plet­ed before treat­ment began, after each week of the 4‑week tri­al, and one week after treat­ment had end­ed. Clin­i­cians mak­ing the rat­ings were also blind to whether par­tic­i­pants were receiv­ing active or sham treatment.

Oth­er mea­sures includ­ed a quan­ti­ta­tive assess­ment of brain­wave activ­i­ty, i.e., qEEG, col­lect­ed before and after treat­ment. The qEEG data was used to deter­mine whether active treat­ment was asso­ci­at­ed with sig­nif­i­cant changes in brain­wave activ­i­ty. Teach­ers also com­plet­ed rat­ings of chil­dren’s class­room behavior.

The Findings:

Dur­ing the 4‑week tri­al, rat­ings of ADHD symp­toms declined sig­nif­i­cant­ly in both groups with sig­nif­i­cant­ly greater declines occur­ring in chil­dren who received active treatment.

In both groups, the bulk of the decline occurred in the first week, with a larg­er decline in the active group. Beyond the first week, chil­dren receiv­ing active treat­ment con­tin­ued to show mod­est declines in symp­tom rat­ings while rat­ings in the sham-treat­ment group remained stable.

After 4 weeks, group dif­fer­ences in ADHD symp­toms rat­ings was in the mod­er­ate range, small­er than what is gen­er­al­ly obtained with stim­u­lant med­ica­tions and about the same as what non-stim­u­lant med­ica­tions typ­i­cal­ly produce.

One week after treat­ment end­ed, symp­tom rat­ings had increased in both groups, but remained low­er in chil­dren who had received active treatment.

Sig­nif­i­cant dif­fer­ences between active and sham-treat­ment groups were also found on the brain­wave activ­i­ty mea­sure, i.e., qEEG. These dif­fer­ences were con­sis­tent with increased acti­va­tion in a vari­ety of brain regions for treat­ed children.

Of par­tic­u­lar inter­est was that these acti­va­tion changes were asso­ci­at­ed with changes in ADHD symp­tom rat­ings. This sug­gests, but does not prove, that treat­ment-relat­ed changes in brain­wave activ­i­ty con­tributed to the reduc­tion on ADHD symptoms.

Treat­ment group dif­fer­ences in behav­ior rat­ings pro­vid­ed by teach­ers was not found.

No adverse effects on TNS were report­ed and it was well tol­er­at­ed by participants.

Summary and implications:

Results from this study indi­cate that TNS is a promis­ing new treat­ment for chil­dren with ADHD. In terms of its impact on core ADHD symp­toms, it appears to be as effec­tive, on aver­age, as non-stim­u­lant ADHD med­ica­tions but less effec­tive than stimulants.

Based on these results, and per­haps oth­er find­ings, TNS was recent­ly cleared by the FDA as an ADHD treat­ment for chil­dren; it should be com­mer­cial­ly avail­able in sev­er­al months.

For par­ents who may even­tu­al­ly con­sid­er this for their child, sev­er­al items should be noted.

First, as not­ed above, avail­able data indi­cates the like­ly impact on core ADHD symp­toms is less than for stim­u­lant medication.

Sec­ond, as with med­ica­tion and behav­ioral treat­ment, pos­i­tive effects are like­ly to reverse when treat­ment is discontinued.

Third, this study did not find pos­i­tive results for teacher rat­ings which is an impor­tant lim­i­ta­tion. And, the pos­si­ble impact on aca­d­e­m­ic func­tion­ing was not assessed. Thus, evi­dence that TNS improves chil­dren’s func­tion­ing at school is lacking.

These con­cerns sug­gest that cau­tion is war­rant­ed in using TNS as a stand alone treat­ment for ADHD in chil­dren. Future work should exam­ine whether it pro­vides incre­men­tal ben­e­fits when used in con­junc­tion with med­ica­tion, behav­ior ther­a­py, or oth­er treat­ment approaches.

It would also be impor­tant to deter­mine whether TNS leads to sig­nif­i­cant improve­ments at school, some­thing that was not found here.

Final­ly, it should be empha­sized that this was a rel­a­tive­ly short tri­al of 4 weeks. Giv­en that chil­dren receiv­ing TNS con­tin­ued to show mod­est declines in ADHD symp­toms dur­ing each week of the tri­al, it is pos­si­ble that addi­tion­al improve­ments would accrue with sus­tained treatment.

If so, the pos­si­ble ben­e­fits of this approach may be greater than what was demon­strat­ed in this ini­tial tri­al. Hope­ful­ly, results from longer tri­als of this treat­ment will be avail­able soon.

– Dr. David Rabin­er is a child clin­i­cal psy­chol­o­gist and Direc­tor of Under­grad­u­ate Stud­ies in the Depart­ment of Psy­chol­o­gy and Neu­ro­science at Duke Uni­ver­si­ty. He pub­lish­es the Atten­tion Research Update, an online newslet­ter that helps par­ents, pro­fes­sion­als, and edu­ca­tors keep up with the lat­est research on ADHD.

The Study in Context:

• Neu­ro­feed­back or med­ica­tion to treat ADHD?
• What are cog­ni­tive abil­i­ties and how to boost them?
• Rates of ADHD diag­no­sis and med­ica­tion treat­ment con­tin­ue to increase substantially