Hypothyroidism Diagnosis Misconceptions and Treatment Despite TSH Levels: Medical Journals

Purpose of this compilation

To show that using only the TSH (thyroid stimulating hormone) level for diagnosis misses many cases of hypothyroidism and leaves those patients without treatment. If patients who are clinically hypothyroid but have a TSH level within the reference range are given a trial of thyroid hormone, a large majority of them can become well.

See also the links in the right column as well as in our T3 References and Desiccated Thyroid sections.

A. Hypothyroidism diagnosis misconceptions
B. Hypothyroidism treatment started with a TSH level in range

A. Hypothyroidism diagnosis misconceptions

1. "Clinical Response to Thyroxine Sodium in Clinically Hypothyroid but Biochemically Euthyroid Patients" (UK, 2000)

...it is increasingly unusual for family practitioners, physicians and endocrinologists to diagnose and treat hypothyroidism in clinically hypothyroid patients unless the free thyroxine (FT4) and/or thyroid stimulating hormone (TSH) falls outside 95% reference intervals. This arises from a current misconception that evidence-based medicine means laboratory-based medicine wherein clinical observation — albeit of an objective nature, for example pulse rate or blood pressure — is accorded lower evidential weight than laboratory measurements. [pp. 115-6]

...TSH values [in 139 patients who were considered hypothyroid by 16 recognized criteria but whose FT4 and/or TSH fell within 95% laboratory reference intervals] were not normally distributed but had a skewed distribution to the lower end of the range...the mean TSH value of 2.00 ± 0.10 was significantly higher than the control average value of 1.0 ± 0.14 (p<0.0001, Table 3)....There was...no correlation between clinical disease as adjudged by these criteria and levels of FT4 or TSH or with TSH/FT4 ratios. [p. 119]

2. "Thyroid function tests: time for a reassessment" (Scotland, 2000)

Overlap between the statistically derived normal and abnormal ranges is accepted in diagnostic tests, giving rise to false positive and false negative results. These concepts have not been applied to measurements of thyroid stimulating hormone. Rather than accepting that the test can be fallible, we transfer the problem to the patient.

3. "Thyroid function tests — time for a reassessment" [response to the responses to his May 2000 article with this title] (Scotland, 2000)

...the clinical features of thyroid dysfunction are now very rarely aired in the medical literature and as a consequence non-experts in the field are given the impression that the clinical assessment of patients for thyroid dysfunction is of little importance.

4. "50 years of commercially motivated fraud relating to thyroid" (US, 1999)

...the mistaken idea of hypothyroidism's low incidence in the population led to the acceptance of dangerously high TSH activity as "normal."

5. "Response" (Canada, 1999)

The maxim of the day before the TSH arrived was you gave enough thyroid until the patient was better...medical students are taught to treat a lab test and not the patient. This has gone a long way to alienate the patient from the doctor and seek alternative practices for relief.

B. Hypothyroidism treatment started with a TSH level in range

1. "Clinical Response to Thyroxine Sodium in Clinically Hypothyroid but Biochemically Euthyroid Patients" (UK, 2000)

Clinical response to thyroxine (T4 only) was examined in 139 patients who were considered hypothyroid by 16 recognized criteria but whose free thyroxine (FT4) and thyroid stimulating hormone (TSH) fell within 95% laboratory reference intervals (133 patients) or whose FT4 or TSH fell within these intervals (6 patients)....

There was improvement or disappearance in all 16 clinical features in 30 patients (22%) and in over 12 features in 106 patients (76%)....Energy loss and poor memory and concentration were most responsive to treatment. [p. 115]

2. "Trial of thyroxine treatment for biochemically euthyroid patients has been approved" (Scotland, 1997)

Since they [patients with symptoms of hypothyroidism and normal results of thyroid function tests] complained of a considerable reduction in their quality of life, which had not been helped by other measures, we decided that it was justifiable to try treating two of them with 100 µg thyroxine daily (after we had explained the lack of scientific rationale and obtained their written consent). Much to our surprise, they both reported a considerable improvement in their condition, while the results of thyroid function tests remained within the reference range....