ORIGINAL ARTICLES   

Minerva Endocrinologica 2000 March;25(1):11-7

Copyright © 2000 EDIZIONI MINERVA MEDICA

language: Italian

Evaluation of treatment with L-Thyroxine: lack of correspondence between objectives and results

Negro R., Dazzi D., Pezzarossa A.

Università degli Studi - Parma, Cattedra di Endocrinologia, Dipartimento di Medicina Interna e Scienze Biomediche

Background. Hypothyroidism and nod­u­lar goi­ter are two fre­quent endo­crine dis­eas­es ­which respec­tive­ly ­require sub­sti­tu­tive and sup­pres­sive treat­ment ­with L-Thyroxine. Objective of ­this ­work was to eval­u­ate the cor­re­spon­dence ­between expect­ed and ­obtained TSH val­ues in ­patients affect­ed ­with hypo­thy­roid­ism and nod­u­lar goi­ter sub­mit­ted to L-Thyroxine treat­ment.
Methods. Setting and sub­jects: a ques­tion­naire ­addressed to ­patients on L-Thyroxine has ­been avail­able in con­sult­ing ­rooms of 12 fam­i­ly doc­tors of Lecce County (Italy) for a 6 ­month peri­od. A hun­dred-­twelve ­patients ­answered the ques­tion­naire: 44 ­were on sup­pres­sive treat­ment for uni/mul­ti­nod­u­lar goi­ter (­group 1) and 68 ­were on sub­sti­tu­tive treat­ment for hypo­thy­roid­ism (­group 2).
Results. TSH dos­age had ­been per­formed ­since ­less ­than 1 ­year in 91% of ­group 1 ­patients and in 87% of ­group 2 ­patients (p=ns), in ­group 1, 25% of TSH val­ues ­were <0.3 µU/ml, 68.2% ­between 0.3 and 4.5 µU/ml, 6.8% >4.5 µU/ml (p<0.001); in ­group 2, 25% of TSH val­ues was <0.3 µU/ml, 63.3% ­between 0.3 and 4.5 µU/ml, 11.8% >4.5 µU/ml: (p<0.001). The dis­tri­bu­tion of TSH val­ues ­between the two ­groups was not sig­nif­i­cant­ly dif­fer­ent. In ­patients on sup­pres­sive treat­ment TSH was sup­pressed in a num­ber of ­patients sig­nif­i­cant­ly ­less in ­respect to the ­ones ­with not sup­pressed TSH val­ue: 11 vs 33; p<0.01; in ­patients on sub­sti­tu­tive treat­ment the num­ber of ­those ­ones ­with TSH val­ues ­in between the nor­mal ­range was not dif­fer­ent ­from ­patients ­with TSH val­ues ­above or ­below the nor­mal ­range: 43 vs 25; p=ns. Considering the two ­groups togeth­er, in 52% of ­patients TSH was not cor­re­spon­dent to ther­a­peu­ti­cal objec­tives.
Conclusions. Inspite of reg­u­lar ­checks of thy­roid func­tion, prop­er TSH val­ues ­were ­achieved only in ­half of ­patients.