502 effect
on
water balance treatment
efficacy in the
in healthy individuals, and its of potomania.
Department of Medicine, Nassau County Medical Center, East Meadow, N.Y. 11554, U.S.A.
TABLE II-VARIATIONS OF P.B.I. AND T IN HYPOTHYROID PATIENTS DURING LITHIUM TREATMENT BEFORE ADMINISTRATION OF THYROID EXTRACTS
JOHN F. ALOIA.
LACTIC ACIDOSIS out to me that there unfortunate error in my letter of July 21 (p. 150). The last but one sentence in the third paragraph should, of " The difference between the two dissociation course, read: constants is 1’36 pH units: at physiological pH, lactic acid is more than twenty times more unionised than pyruvic acid ". In reply to Dr Gent (July 28, p. 198), I should like to state that, although the percentage change is small, the production of lactate from pyruvate is associated with a reduction in hydrogen-ion concentration and should therefore not be terminologically grouped with the lesion causing acidosis.
SiR,-Sir Hans Krebs has pointed
was an
Department of Chemical Pathology, Westminster Hospital, London SW1.
*
Significant decrease:
P <
0’001
(Fisher
exact
variation of the
protein-bound iodine and T during treat(table i). However, in the group of hypothyroid patients, P.B.I. and 1B decreased significantly as early as 4 weeks after treatment with lithium began (table 11). From our standpoint, we cannot rule out the possibility that lithium acts as triggering agent for latent hypothyroidism only in predisposed patients. We suggest that, before treatment with lithium and after it has begun, particularly in the first 12-16 weeks, a close watch should be kept on thyroid function (palpation, P.B.I., T4, and perhaps thyroidstimulating hormone). ment
P. M. CARTER.
A. VILLENEUVE J. GAUTIER A. Jus D. PERRON.
Research Department, St.
Michel-Archange Hospital, Quebec, P.Q. G1J 2G3, Canada.
EFFECT OF LITHIUM ON THYROID IN MAN SiR,-Since lithium was used for the treatment of manic excitation,1 several authors (not all mentioned here) have observed that this ion modified the activity of the thyroid gland. 2-6 However, a survey of the literature has shown that very few systematic studies have been undertaken to assess the exact influence of lithium on thyroid function, and data about the thyroid disturbances are unsatisfactory. In 149 patients (56 males and 93 females) we studied, who were treated with lithium for from 4 to 38 months
(mean, 22 months), we noted a very high frequency of hypothyroidism coinciding with lithium-carbonate treatment (14-7%, 20 females and 2 males). In these patients, before treatment began, no thyroid disturbance was detected. The increase in hypothyroidism associated with this treatment was commoner in females. Even though in the general population hypothyroidism is more frequent in females, the increased risk seems higher than normal in females treated with lithium and we cannot explain this finding. In our patients, except for the sex variable, age, length of treatment, or type of psychosis did not seem to influence the risk of thyroid disturbances. Contrary to some views,6 we have been unable to detect any significant 1. 2. 3. 4. 5. 6.
Cade, J. F. J. Med. J. Aust. 1949, 36, 349. Schou, M., Amdisen, A. Br. med. J. 1968, iii, 710. Fieve, R. R., Platman, S. R. Am. J. Psychiat. 1969, 125, 149. Villeneuve, A., Langlois, M., Chabot, C., Dogan, K., Lachance, R., St-Laurent, C. Int. J. clin. Pharmacol. 1971, 3, 303. Emerson, C. H., Dyson, W. L., Utiger, R. D. J. clin. Endocr. Metab. 1972, 36, 338. Rogers, M. P., Whybrow, P. C. Am. J. Psychiat. 1971, 128, 138.
PROLACTIN, PHENOTHIAZINES, ADMISSION TO MENTAL HOSPITAL, AND CARCINOMA OF THE BREAST
SiR,-We read with interest in the letter by Dr Ettigi (Aug. 4, p. 266) that, although their results are not significant (0-50 >p> 0-30), the trend of their data indicates a higher incidence of carcinoma of the breast in patients who have had phenothiazine therapy. and others
We conducted a retrospective survey of the causes of deaths in three mental hospitals. We examined the death certificates and medical dossiers of 503 women who died between 1965 and 1972 and compared the mortalities to those of the general Belgian female population in 1968.1 The age at death of the mental patients was slightly lower than that of the general population, but there was no difference with the various medications. Considerably more mental patients died of cerebral arteriosclerosis and ill-defined conditions of the central nervous system leading to total emaciation. As this was obviously due to a selection factor, many patients being admitted to the hospital for these conditions, the two causes were excluded for further analysis and all data were corrected for the exclusion. After correction, the incidence of mammary cancer was still smaller in the mental patients (5-2%) than in the 1.
Bevolkings-statistieken, Statistieken
probability test).
no
van
doodsoorzaken, National Kingdom
Institute for Statistics, Ministry of Economic Affairs, of Belgium, 1972.
TABLE I-EFFECT OF LITHIUM ON P.B.I. AND
*Values expressed in µg. per 100 ml. (mean ±S.D.):
probability test).
T4
VALUES
statistically significant change during
treatment
for the total
population (Fisher
exact