(b).

Condition	Reference	Sample	Prevalence
Associated conditions
Obesity	Ehrmann et al. [41]	394	80%
	Hahn et al. [40]	200	52%
	Azziz et al. [42]	267	42%
Insulin resistance	Carmina and Lobo [43]	267	77%
	Hahn et al. [40]	200	71%
Impaired fasting glucose	Ehrmann et al. [41]	122	35%
	Legro et al. [44]	254	31.1%
Type 2 diabetes mellitus	Legro et al. [44]	254	7.5%
	Ehrmann et al. [41]	394	6.6%
Arterial hypertension	Ehrmann et al. [41]	394	21%
	Elting et al. [45]	346	9%
Dyslipidemia	Hahn et al. [40]	200	46.3%
	Ehrmann et al. [41]	394	32%
Metabolic syndrome	Dokras et al. [46]	129	47.3%
	Apridonidze et al. [13]	106	43%
Mood disorders	Jedel et al. [36]	30	53%
	Hollinrake et al. [47]	103	21%

All studies cited were carried out in adults.