Is there an after effect of a 'leptin deficiency'?

Thyroid issues: Thyroid function is closely related to leptin's secretion by the adipose tissue. In states of leptin-deficiency, the circadian rhythm of TSH is altered, leading to central hypothyroidism in animal models. In humans, central hypothyroidism has also been described in rare cases of congenital leptin deficiency.

Fat hormone: Leptons are hypothesized to be a hormone released to control fat metabolism. It has been shown in mice to be effective in fat control, but not in humans. At this point, there are no significant effects of a deficiency.