Effect of vitamin supplementation on polycystic ovary syndrome and key pathways implicated in its development: A Mendelian randomization study

Table 1 Details of the genome-wide association studies included in this Mendelian randomization analysis

Exposures/Outcomes	Consortium	Ethnicity	Participants	Number of SNPs
Vitamin D	United Kingdom Biobank	European	496946	6896093
Vitamin K	CHAGRE	European	2138	/
Vitamin E	ATBC&PLCO&NHS	European	7781	/
Vitamin A	ATBC&PLCO&NHS	European	7778	/
Vitamin B12	SIID	European	45576	/
Polycystic ovarian syndrome	FinnGen Biobank	European	118870	16379676
Hyperlipidaemia	FinnGen Biobank	European	201497	16380389
Obesity	FinnGen Biobank	European	218735	16380465
Insulin resistance	MAGIC	European	37037	2435028

SNPs: Single nucleotide polymorphisms.

Table 2 Heterogeneity and pleiotropy tests of the Mendelian randomization analysis

Exposure/Outcome	Heterogeneity		Pleiotropy
	Cochran’s Q	P value	Egger-intercept	P value
Vitamin D/PCOS	180.692	0.368	-0.006	0.487
Vitamin D/Hyperlipidaemia	449.648	< 0.001	-0.004	0.425
Vitamin D/Obesity	402.633	< 0.001	0.002	0.494
Vitamin D/Insulin resistance	169.312	0.001	-0.002	0.059
Vitamin K/PCOS	2.926	0.570	0.029	0.752
Vitamin K/Hyperlipidaemia	5.151	0.272	0.044	0.290
Vitamin K/Obesity	7.086	0.131	0.049	0.150
Vitamin K/Insulin resistance	7.932	0.094	-0.008	0.469
Vitamin B12/PCOS	1.284	0.973	0.004	0.930
Vitamin B12/Hyperlipidaemia	3.346	0.764	-0.022	0.297
Vitamin B12/Obesity	5.046	0.540	0.003	0.858
Vitamin B12/Insulin resistance	3.578	0.466	-0.003	0.451

PCOS: Polycystic ovary syndrome.

Table 3 Mendelian randomization PRESSO estimates for effect of vitamin supplements on risk of polycystic ovary syndrome and its risk factors

Exposure trait	Outcome trait	N	Beta	P value
Vitamin D	PCOS	172	-0.092	0.645
Vitamin D	Hyperlipidaemia	169	-0.141	0.126
Vitamin D	Obesity	174	-0.031	0.618
Vitamin D	Insulin resistance	117	-0.005	0.789
Vitamin B12	PCOS	6	-0.284	0.005
Vitamin B12	Hyperlipidaemia	6	-0.103	0.063
Vitamin B12	Obesity	6	-0.088	0.048
Vitamin B12	Insulin resistance	6	-0.015	0.319

PCOS: Polycystic ovary syndrome.