What is subclinical hypothyroidism?

Elevated TSH w/normal fT4, most often caused by autimmune (hashimoto) thyroiditis, anti-TPO pt w/ subclinical are at high risk to get overt. May be associated w/increased risk of HF, CAD, coginitive impairment, non-specific symptoms of fatigue, mood alteration (middle aged pt). Tx (can be observed w/out tx, or tx indicated if TSH>10 or TSH between 5-10 w/goiter or + anti-TPO, young pt