Biomaterial

Thyroid function


LASAC865

Contact: Natasja van Schoor

Background
Thyroid diseases, such as goiter and functional disturbances including hyperthyroidism and hypothyroidism are very common in the population. Hyperthyroidism (increased production of thyroid hormone) can lead to osteoporosis and may aggravate cardiovascular disease. Hyperthyroidism is associated with weight loss, sweating, nervousness and emotional disturbances. Hypothyroidism (decreased function of the thyroid gland) also is quite common especially in older persons. It is associated with weight gain, slow speech, low body temperature and obstipation. It also may lead to cardiovascular disease. This document describes the measurement of thyroid stimulating hormone (TSH) made in the pituitary, thyroxin (T4) and tri-jodothyronin (T3), the two thyroidhormones.

Measurements in LASA

Blood collection
Morning blood samples were collected in 1995 en 1996. Subjects were allowed to eat toast and drink tea but no dairy products.

Measurement procedure & variable information
Thyroid hormones were measured in frozen serum samples in 2001. In all persons TSH was measured. When TSH was < 0.3 mU/l or > 4.5 mU/l then thyroxin (T4) was measured. When T4 was normal, then T3 was measured. TSH was measured by radio-immunometric assay (Centaur, Bayer Diagnostics, Mijdrecht) with an interassay CV of 6%; free T4 was measured by a competitive immunoassay (Centaur, Bayer Diagnostics, Mijdrecht) with an interassay CV of 7%; free T3 was also measured by a competitive immunoassay.

Availability of data per wave

Numbers per wave

Thyroid stimulating hormone (TSH)

 

B

C

 
2B*

G



3B*

All regions

 

1331

 

 

 

* 2B=baseline second cohort;
   3B=baseline third cohort

Tri-jodothyronin (T3)

 

B

C

 
2B*

G



3B*

All regions

 

1331

 

 

 

* 2B=baseline second cohort;
   3B=baseline third cohort

Thyroxin (T4)

 

B

C

 
2B*

G



3B*

All regions

 

1331

 

 

 

* 2B=baseline second cohort;
   3B=baseline third cohort

Previous use in LASA
Several studies have been published that used data of thyroid function measurements within LASA. Rabelink et al. (2011) reported that self-reported loss of consciousness after head trauma does not predispose to hypopituitarism including secondary hypothyroidism in an older population.

Heima et al. (2013) showed that subjects with a serum TSH in the upper quartile have a higher prevalence of metabolic syndrome as compared with subjects with a serum TSH in the lowest quartile. Research of Schindhelm et al. (2013) stated that in a cohort of older subjects, free T4, but not TSH, was associated with erythrocyte indices, confirming the role of thyroid hormones in the regulation of erythropoiesis. De Jongh et al. (2011) studied to what extent endogenous subclinical thyroid disorders contribute to impaired physical and cognitive function, depression, and mortality in older individuals. This study did not support disadvantageous effects of subclinical thyroid disorders on physical or cognitive function, depression, or mortality in an older population.

  • De Jongh, R.T., Lips, P.T.A., Van Schoor , N.M., Rijs, K.J., Deeg, D.J.H., Comijs, H.C., Kramer, M.H.H., Vandenbroucke, J.P., Dekkers, O.M. (2011). Endogenous subclinical thyroid disorders, physical and cognitive function, depression, and mortality in older individuals. European Journal of Endocrinology, 165, 545-554.
  • Heima, N.E., Eekhoff, E.M.W., Oosterwerff, M.M., Lips, P.T.A., Van Schoor , N.M., Simsek, S. (2013). Thyroid function and the metabolic syndrome in older persons: a population-based study. European Journal of Endocrinology, 168, 59-65.
  • Rabelink NM, Peeters GMEE, van Schoor NM, Drent ML, Lips P. (2011) Self-reported loss of consciousness after head trauma does not predispose to hypopituitarism in an older population. Journal of Head Trauma Rehabilitation, 26(1), 90-97.
  • Schindhelm, R.K., Ten Boekel, E., Heima, N.E., Van Schoor , N.M., Simsek, S. (2013). Thyroid hormones and erythrocyte indices in a cohort of euthyroid older subjects. European Journal of Internal Medicine, 24 (3), 241-244.