Table 4.

Subgroup analyses of the association between circulating LC n-3 PUFAs and risk of HF.

	Studies (N)	Quintile 5 versus Quintile 1		Per 1 SD increment
		HR (95% CI)	p value a /I2	HR (95% CI)	p value a /I2
Average age (years)
<60	2	0.86 [0.64, 1.16]	0.11/59.8%	0.95 [0.86, 1.05]	0.11/60.3%
⩾60	4	0.43 [0.19, 0.97]		0.74 [0.55, 0.99]
Sex
Female	1	0.37 [0.16, 0.84]	0.03/78.8%	0.70 [0.52, 0.95]	0.04/75.9%
Male	2	0.98 [0.71, 1.34]		0.98 [0.87, 1.11]
Follow-up duration (years)
<10	4	0.70 [0.45, 1.08]	0.45/0%	0.88 [0.75, 1.03]	0.44/0%
⩾10	2	0.39 [0.09, 1.63]		0.71 [0.42, 1.19]
Region
United States	5	0.67 [0.44, 1.02]	0.08/68.3%	0.86 [0.74, 1.00]	0.08/66.7%
Asia	1	0.28 [0.12, 0.67]		0.64 [0.47, 0.86]
Measure of exposure
EPA + DHA	3	0.36 [0.14, 0.92]	0.08/67.7%	0.69 [0.49, 0.97]	0.08/68.1%
EPA + DHA + DPA	3	0.87 [0.65, 1.17]		0.95 [0.86, 1.06]
Tissue type
Serum	2	0.23 [0.12, 0.42]	<0.001/93.6%	0.58 [0.47, 0.72]	<0.001/94.2%
Plasma phospholipid	4	0.87 [0.69, 1.08]		0.95 [0.88, 1.03]
Measuring method
GC	3	0.75 [0.46, 1.24]	0.35/17.3%	0.90 [0.75, 1.08]	0.30/16.9%
GC-FID	2	0.32 [0.11, 0.90]		0.66 [0.45, 0.97]
GLC	1	0.77 [0.47, 1.26]		0.91 [0.77, 1.08]
Type of HF
HFpEF	2	0.27 [0.02, 3.86]	0.71/0%	0.63 [0.24, 1.65]	0.74/0%
HFrEF	2	0.49 [0.10, 2.37]		0.76 [0.43, 1.34]

CI, confidence interval; DHA, docosahexaenoic acid; DPA, docosapentaenoic acid; EPA, eicosapentaenoic acid; GC, gas chromatography; GC-FID, gas-chromatograph/flame-ionization-detector; GLC, gas-liquid chromatogram; HF, heart failure; HFpEF, heart failure with preserved ejection fraction; HFrEF, heart failure with reduced ejection fraction; HR, hazard ratio; LC, long chain; PUFAs, polyunsaturated fatty acids; SD, standard deviation.

^aFor heterogeneity among subgroups.