Hypothyroidism is the failure of the thyroid gland to produce enough hormones. It can cause hypertension, dyslipidemia, infertility and other issues if untreated. It is most common in females and prevalence increases with age. Thyroid dysfunction is more common in diabetics than the general population. Screening is recommended for diabetics and those with risk factors like autoimmune disease or family history. A TSH test is used to diagnose, and levothyroxine replacement is the standard treatment, with dosage based on weight. Subclinical hypothyroidism may also be treated in high risk groups.

1. Mahmood Hamed AL-Haddabi
R1 Family Medicine
Hypothyroidism

2. objectives
 Definition.
 Introduction.
 Causes
 Clinical presentation
 Diagnosis and treatment

3. Definition
failure of the thyroid gland to produce
sufficient thyroid hormone to meet the
metabolic demands of the body.

4. Untreated hypothyroidism contribute to :
 hypertension.
 dyslipidemia.
 infertility.
 cognitive impairment.
 neuromuscular dysfunction

5.  one in 300 persons in the US has
hypothyroidism.
 The prevalence increases with age, and
is higher in females than in males

7.  Thyroid dysfunction was found in 12.6 % of
the diabetic
patients compared to 4.9% in the control group.
The prevalence was higher among the diabetic
females (86%) compared to diabetic males
(14%).

8.  The commonest thyroid dysfunction among
diabetics was overt hypothyroidism (4.6%).
 Subclinical hypothyroidism was the
commonest thyroid dysfunction seen in less
controlled diabetics at a mean HbA1c of 7.8 (±
0.7).

9. Conclusion:
 Screening for thyroid dysfunction in patients
with type 2 diabetes mellitus should be
routinely performed considering the higher
prevalence of thyroid diseases in this group
compared to the general population.

10. causes
 Primary gland failure :
 congenital abnormalities
 autoimmune destruction (Hashimoto disease)
 iodine deficiency
 infiltrative diseases

11.  Disorders associated with transient
hypothyroidism :
 postpartum thyroiditis.
 subacute thyroiditis.
 silent thyroiditis.
 thyroiditis associated with thyroid-stimulating
hormone (TSH) receptor-blocking antibodies

12.  Central causes of hypothyroidism
 hypothalamic or pituitary dysfunction .
 characterized by inappropriately normal or low
levels of TSH relative to insufficient thyroid
hormone

13.  Drugs associated with thyroid dysfunction :
 lithium.
 Amiodarone.
 interferon alfa.
 interleukin-2
 tyrosine kinase inhibitors

14. Clinical Presentation

16. Screening and Diagnosis
-The American Academy of Family
Physicians does not recommend
screening for hypothyroidism in
asymptomatic adults.
-U.S. Preventive Services Task Force
found insufficient evidence for
routine screening in this population.

17.  should evaluate in all patients with symptoms of
hypothyroidism
 Screening of asymptomatic patients may be
considered in:
 history of autoimmune disease.
 history of head or neck irradiation.
 previous radioactive iodine therapy.
 presence of a goiter.
 family history of thyroid disease.
 or treatment with drugs known to influence thyroid
function

18.  The best laboratory assessment of
thyroid function, is a serum TSH test.
 If the serum TSH level is elevated,
testing should be repeated with a serum
free thyroxine (T4) measurement

20. Treatment
 The starting dose of levothyroxine in young,
healthy adults for complete replacement is 1.6
mcg per kg per day.
Instructions:
 taken in the morning, 30 minutes before eating.
 Calcium and iron supplements should not be
taken within four hours .

23. SUBCLINICAL
HYPOTHYROIDISM
Treatment should be considered for patients
with:
 initial TSH levels greater than 10 mIU per L.
 patients with elevated thyroid peroxidase
antibody titers.
 patients with symptoms suggestive of
hypothyroidism and TSH levels between 5 and 10
mIU per L .
 patients who are pregnant or are attempting to

24.  PATIENTS WITH PERSISTENT SYMPTOMS :
 Investigates an alternative cause for their
symptoms

25.  Combination T3/T4 therapy sometimes prescribed for
patients with persistent symptoms of hypothyroidism.
 meta-analysis of 11 randomized controlled trials of
combination T3/T4 therapy versus T4 monotherapy
showed no improvements in bodily pain, depression,
or quality of life.
 A subsequent study showed that a small subset of
patients who have a specific type 2 deiodinase
polymorphism may benefit from combination therapy

28. Reference
 American Family Physician , August 1, 2012 ◆
Volume 86, Number 3