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THYROID FUNCTION IN AFFECTIVE DISORDERS
964
patients had a raised triglyceride level after adequate replacement therapy it still would not follow that this was a more sensitive index of thyroid failure than the serumT.S.H.
concentration.
(iv) Finally-although we would agree that undue reliance should not be placed on a single test-a diagnostic index of the type described by Dr Fowler does not help. Any index which scores heavily those factors which have already been used to formulate a diagnosis will inevitably confirm " that diagnosis in most subjects. The quality of a diagnostic index can only be assessed by reference to some independent criterion or criteria.
Sephadex G-25 column (’ Trilute ’ kit), and free thyroxine index (FTJ) calculated by multiplication of total thyroxine iodine (T4-1) and triiodothyronine 1251 uptake.7,1 The results were: Thyroid function in patients before therapy (mean values* with S.E.M. and T.-I (!J.g. RT3U% FTJ
D. C. EVERED R. HALL.
SIR,-Dr Toft and his colleagues (Sept. 22, p. 644) have shown that plasma-T.s.H. values after iodine-131 treatment are often high for a long time, even in the absence of overt clinical hypothyroidism. In fact, of course, hypothyroidism must be considered sooner or later in the majority of patients treated with 1311 if they live long enough.1 As the authors point out, it remains to be shown which effects may be produced by the constant T.S.H. stimulation of the functional thyroid remnant in these patients. Goitre formation is, of course, one of the possibilities. A normal serum-p.B.I. and/or serum-T4 value in a patient who has been treated with 1311 and has high plasma-T.s.H. does not per se indicate that the thyroid function is normal. Such values are often seen in connection with an overstimulated functional thyroid remnant with rapid conversion of thyroid hormones and recirculation of iodine within a small hormone pool. This state is characterised by thyrotoxicosis-like symptoms and signs, and is terminated with the aid of thyroxine treatment.2 If thyrotoxicosis-like symptoms and signs are seen in a patient who has been treated with 1311 and who has normal serum-p.B.I. and serum-T4 values but high plasma-T.s.H., treatment with thyroxine should thus be considered. The need for such treatment is confirmed by a high serumP .B. 131 value. Department of Internal Medicine, Aland Central Hospital, SF-22100 Mariehamn, Aland Islands, Finland.
PETER WAHLBERG.
THYROID FUNCTION IN AFFECTIVE DISORDERS
SiR,—Dr Rybakowski and Dr Sowinski (April 21, p. 889), by the estimation of free thyroxine index and absolute free thyroxine, have drawn attention to the presence of primary thyroid dysfunction with hypothyroidism in mania as well as in the depression. At the psychiatric hospital of Volterra (Pisa), in a study of 10 patients (age range 25-52) with affective disorders of depressive type, before any therapy, a significantly low thyroid function was not detected. Thyroid function was investigated by the estimation, in venous blood-samples obtained at 8 A.M., of total thyroxine iodine by a radiocompetitive method 3.4 (modification of Bauer et al.s and Braverman et al. 6) (’Tetralute’ kit), triiodothyronine 1251 uptake (RTgU) in 1. 2.
3. 4. 5. 6.
Beling, U., Einhorn, J. Acta radiol. 1961, 66, 275. Wahlberg, P., von Knorring, J., Nyman, D. Acta med. scand. 1972, 191, 141. Murphy, B. E. P., Pattee, C. J. J. clin. Endocr. 1964, 24, 187. Murphy, B. E. P., Jachan, C. J. Lab. clin. Med. 1965, 66, 161. Bauer, R., Schick, L. A., Phillips, B. F., Rupe, C. O., Gross, J., Gordon, A. Clin. Chem. 1970, 16, 526. Braverman, L. E., Vagenakis, A. G., Foster, A. E., Ingbar, S. H. J. clin. Endocr. 1971, 32. 497.
ml.) *
"
Department of Medicine, Wellcome Research Laboratories, Royal Victoria Infirmary, Newcastle upon Tyne NE1 4LP.
per 100
normal values) 4’1:t 0’5 44-1 ±1-8 8-9 ±1-1 Three determinations.
3.5-8.0 41-57 3-0-9-2
In our patients the three values indicated normal thyroid function. Our results, though from a small number of patients, do not point to the presence of a primary thyroid dysfunction in depressive disorders. Department of Medicine, Psychiatric Hospital of Volterra, 56048 Volterra (Pisa), Italy.
FRANCESCO SALVADORINI PAOLO SABA.
THYROID FUNCTION AFTER MYOCARDIAL INFARCTION
SIR,—There is conflicting evidence on the relevance validity of studies relating thyroid antibodies, thyroid function, serum-cholesterol, and coronary heart-disease. Some would have us believe that thyroiditis is an important predisposing factor for hypercholesterolamua and coronary and
heart-disease in men and women 9 and others for women only.1-0 Dr Mathews and co-workers (Oct. 6, p. 754) now suggest that thyroid antibodies are merely markers for the disease. Studies have failed to find higher levels of T.S.H. and thyroglobulin antibodies in patients with coronary heartdisease than controls 11 and that T.s.H. levels are similar in hypercholesterolsemic adults and controls.12 As clinicians should we be screening young patients with vascular disease or even symptomless people for the presence of thyroid antibodies and early hypothyroidism ? We have examined blood from 46 patients three months after well-documented myocardial infarction, treated in the coronary-care unit, Frenchay Hospital. Patients with diabetes mellitus and other diseases associated with vascular disease were excluded. Aged ranged from 35 to 74, and 8 were women.
(1) All had a serum thyroxine iodine level above 4-0 tg. per 100 ml. (normal 3-5-8-0). (2) All had a free-thyroxine index (F.T.I.) of 3-5 or more except 2 with levels of 3-3 and 3-0 (normal 3-5-8-0). These patients had T.S.H. levels less than 2 p.u per ml. and tanned redcell tests for thyroglobulin antibodies were negative. (3) All had serum T.S.H. levels less than 2 ?u per ml. except 3 with values of 3-3, 3-4, and 4-3 (normal less than 5 !J.U per ml.). These three had F.T.I. levels of 5-1, 4-6, and 4-5 and were negative for thyroglobulin antibodies. (4) All had negative tests for thyroglobulin antibodies except two with titres of 1/5 and 1/25, which we consider insignificant. Their T.s.H. levels were both less than 2 gu per ml. and F.T.LS 55 and 46. (5) Serum-cholesterol increased and the F.T.I. decreased with age. In this highly selected group there was a tendency for serum-cholesterol and F.T.I. to be inversely related, but age could have accounted for this. These results show that none of 38 men and 8 women who survived three months after a myocardial infarction had definite evidence of thyroid hypofunction or thyroiditis as assessed by the tanned red-cell test for thyroglobulin 7. Thoma, G. E., Leightner, W. F. Med. Clins N. Am. 1968, 52, 463. 8. Gorman, C. A., McConahey, W. N. ibid. 1970, 54, 1037. 9. Fowler, P. B. S., Swale, J., Andrews, H. Lancet, 1970, ii, 488. 10. Bastenie, P. A., Vanhaelst, L., Bonnyns, M., Neve, P., Staquet, M. ibid. 1971, i, 203. 11. Heinonen, O. P., Gordin, A., Aho, K., Punsar, S., Pyorala, K., Puro, K. ibid. 1972, i, 785. 12. Hedstrand, H., Wide, L. ibid. 1973, i, 490.
patients had a raised triglyceride level after adequate replacement therapy it still would not follow that this was a more sensitive index of thyroid failure than the serumT.S.H.
concentration.
(iv) Finally-although we would agree that undue reliance should not be placed on a single test-a diagnostic index of the type described by Dr Fowler does not help. Any index which scores heavily those factors which have already been used to formulate a diagnosis will inevitably confirm " that diagnosis in most subjects. The quality of a diagnostic index can only be assessed by reference to some independent criterion or criteria.
Sephadex G-25 column (’ Trilute ’ kit), and free thyroxine index (FTJ) calculated by multiplication of total thyroxine iodine (T4-1) and triiodothyronine 1251 uptake.7,1 The results were: Thyroid function in patients before therapy (mean values* with S.E.M. and T.-I (!J.g. RT3U% FTJ
D. C. EVERED R. HALL.
SIR,-Dr Toft and his colleagues (Sept. 22, p. 644) have shown that plasma-T.s.H. values after iodine-131 treatment are often high for a long time, even in the absence of overt clinical hypothyroidism. In fact, of course, hypothyroidism must be considered sooner or later in the majority of patients treated with 1311 if they live long enough.1 As the authors point out, it remains to be shown which effects may be produced by the constant T.S.H. stimulation of the functional thyroid remnant in these patients. Goitre formation is, of course, one of the possibilities. A normal serum-p.B.I. and/or serum-T4 value in a patient who has been treated with 1311 and has high plasma-T.s.H. does not per se indicate that the thyroid function is normal. Such values are often seen in connection with an overstimulated functional thyroid remnant with rapid conversion of thyroid hormones and recirculation of iodine within a small hormone pool. This state is characterised by thyrotoxicosis-like symptoms and signs, and is terminated with the aid of thyroxine treatment.2 If thyrotoxicosis-like symptoms and signs are seen in a patient who has been treated with 1311 and who has normal serum-p.B.I. and serum-T4 values but high plasma-T.s.H., treatment with thyroxine should thus be considered. The need for such treatment is confirmed by a high serumP .B. 131 value. Department of Internal Medicine, Aland Central Hospital, SF-22100 Mariehamn, Aland Islands, Finland.
PETER WAHLBERG.
THYROID FUNCTION IN AFFECTIVE DISORDERS
SiR,—Dr Rybakowski and Dr Sowinski (April 21, p. 889), by the estimation of free thyroxine index and absolute free thyroxine, have drawn attention to the presence of primary thyroid dysfunction with hypothyroidism in mania as well as in the depression. At the psychiatric hospital of Volterra (Pisa), in a study of 10 patients (age range 25-52) with affective disorders of depressive type, before any therapy, a significantly low thyroid function was not detected. Thyroid function was investigated by the estimation, in venous blood-samples obtained at 8 A.M., of total thyroxine iodine by a radiocompetitive method 3.4 (modification of Bauer et al.s and Braverman et al. 6) (’Tetralute’ kit), triiodothyronine 1251 uptake (RTgU) in 1. 2.
3. 4. 5. 6.
Beling, U., Einhorn, J. Acta radiol. 1961, 66, 275. Wahlberg, P., von Knorring, J., Nyman, D. Acta med. scand. 1972, 191, 141. Murphy, B. E. P., Pattee, C. J. J. clin. Endocr. 1964, 24, 187. Murphy, B. E. P., Jachan, C. J. Lab. clin. Med. 1965, 66, 161. Bauer, R., Schick, L. A., Phillips, B. F., Rupe, C. O., Gross, J., Gordon, A. Clin. Chem. 1970, 16, 526. Braverman, L. E., Vagenakis, A. G., Foster, A. E., Ingbar, S. H. J. clin. Endocr. 1971, 32. 497.
ml.) *
"
Department of Medicine, Wellcome Research Laboratories, Royal Victoria Infirmary, Newcastle upon Tyne NE1 4LP.
per 100
normal values) 4’1:t 0’5 44-1 ±1-8 8-9 ±1-1 Three determinations.
3.5-8.0 41-57 3-0-9-2
In our patients the three values indicated normal thyroid function. Our results, though from a small number of patients, do not point to the presence of a primary thyroid dysfunction in depressive disorders. Department of Medicine, Psychiatric Hospital of Volterra, 56048 Volterra (Pisa), Italy.
FRANCESCO SALVADORINI PAOLO SABA.
THYROID FUNCTION AFTER MYOCARDIAL INFARCTION
SIR,—There is conflicting evidence on the relevance validity of studies relating thyroid antibodies, thyroid function, serum-cholesterol, and coronary heart-disease. Some would have us believe that thyroiditis is an important predisposing factor for hypercholesterolamua and coronary and
heart-disease in men and women 9 and others for women only.1-0 Dr Mathews and co-workers (Oct. 6, p. 754) now suggest that thyroid antibodies are merely markers for the disease. Studies have failed to find higher levels of T.S.H. and thyroglobulin antibodies in patients with coronary heartdisease than controls 11 and that T.s.H. levels are similar in hypercholesterolsemic adults and controls.12 As clinicians should we be screening young patients with vascular disease or even symptomless people for the presence of thyroid antibodies and early hypothyroidism ? We have examined blood from 46 patients three months after well-documented myocardial infarction, treated in the coronary-care unit, Frenchay Hospital. Patients with diabetes mellitus and other diseases associated with vascular disease were excluded. Aged ranged from 35 to 74, and 8 were women.
(1) All had a serum thyroxine iodine level above 4-0 tg. per 100 ml. (normal 3-5-8-0). (2) All had a free-thyroxine index (F.T.I.) of 3-5 or more except 2 with levels of 3-3 and 3-0 (normal 3-5-8-0). These patients had T.S.H. levels less than 2 p.u per ml. and tanned redcell tests for thyroglobulin antibodies were negative. (3) All had serum T.S.H. levels less than 2 ?u per ml. except 3 with values of 3-3, 3-4, and 4-3 (normal less than 5 !J.U per ml.). These three had F.T.I. levels of 5-1, 4-6, and 4-5 and were negative for thyroglobulin antibodies. (4) All had negative tests for thyroglobulin antibodies except two with titres of 1/5 and 1/25, which we consider insignificant. Their T.s.H. levels were both less than 2 gu per ml. and F.T.LS 55 and 46. (5) Serum-cholesterol increased and the F.T.I. decreased with age. In this highly selected group there was a tendency for serum-cholesterol and F.T.I. to be inversely related, but age could have accounted for this. These results show that none of 38 men and 8 women who survived three months after a myocardial infarction had definite evidence of thyroid hypofunction or thyroiditis as assessed by the tanned red-cell test for thyroglobulin 7. Thoma, G. E., Leightner, W. F. Med. Clins N. Am. 1968, 52, 463. 8. Gorman, C. A., McConahey, W. N. ibid. 1970, 54, 1037. 9. Fowler, P. B. S., Swale, J., Andrews, H. Lancet, 1970, ii, 488. 10. Bastenie, P. A., Vanhaelst, L., Bonnyns, M., Neve, P., Staquet, M. ibid. 1971, i, 203. 11. Heinonen, O. P., Gordin, A., Aho, K., Punsar, S., Pyorala, K., Puro, K. ibid. 1972, i, 785. 12. Hedstrand, H., Wide, L. ibid. 1973, i, 490.