Final answer:
Hypothyroidism in adults is primarily associated with generalized edema, not with exophthalmos, weight loss, tachycardia, or mental defects that are notably reduced mental activity due to a low production of thyroid hormones.
Step-by-step explanation:
Hypothyroidism in adults is associated with generalized edema. This condition is caused by an underproduction of thyroid hormones, leading to symptoms such as a low metabolic rate, weight gain, sensitivity to cold, and reduced mental activity. In contrast, hyperthyroidism, which is an overproduction of thyroid hormones, often results in symptoms like weight loss, heat intolerance, and tachycardia.
Specifically, hypothyroidism does not typically cause exophthalmos (bulging eyes), weight loss, or tachycardia as these are more closely associated with hyperthyroidism. Instead, adults with hypothyroidism may experience myxoedema, where the skin becomes thick, dry, and waxy, and mental defects such as dull mental ability and reduced mental activity.