Importance: The major polyunsaturated fatty acids in adipose tissue objectively reflect long-term dietary intake, and may provide more reliable information than would self-reported intake. Whether adipose tissue fatty acids predict cardiovascular and all-cause mortality needs investigation.
Objective: To investigate associations between adipose tissue fatty acids and cardiovascular and overall mortality in a cohort of elderly men.
Design, Setting, and Participants: We hypothesized that polyunsaturated fatty acids reflecting dietary intake, are inversely associated with cardiovascular and all-cause mortality. In the Swedish cohort study Uppsala Longitudinal Cohort of Adult Men, buttock fatty acid composition was analyzed by gas-liquid chromatography in 1992 to 1993 and 2008. The study participants were followed during 11 311 person-years, between 1991 and 2011 (median follow-up, 14.8 years). In this community-based study that took place from 1970 to 1973, all men born in 1920 to 1924 in Uppsala, Sweden, were invited and 2322 (82%) were included (at age 50 years). At the reinvestigation at age 71 years, 1221 (73%) of the 1681 invited men participated. Adipose tissue biopsy specimens were taken in a subsample of 853 men. There was no loss to follow-up.
Exposures: Adipose tissue proportions of 4 polyunsaturated fatty acids that were considered to mainly reflect dietary intake (linoleic acid, 18:2n-6; α-linolenic acid, 18:3n-3; eicosapentaenoic acid, 20:5n-3; and docosahexaenoic acid, 22:6n-3) comprised primary analyses, and all other available fatty acids were secondary analyses.
Main Outcomes and Measures: Hazard ratios (HRs) for cardiovascular and all-cause mortality using Cox proportional hazards regression analyses, performed in 2015.
Results: Among the 853 Swedish men, there were 605 deaths, of which 251 were cardiovascular deaths. After adjusting for risk factors, none of the 4 primary fatty acids were associated with cardiovascular mortality (HR, 0.92-1.05 for each standard deviation increase; P ≥ .27). Linoleic acid was inversely associated with all-cause mortality (HR, 0.90; 95% CI, 0.82-0.98; P = .02) and directly associated with intake (P < .001). In secondary analyses, palmitoleic acid, 16:1n-7 (HR, 1.11; 95% CI, 1.02-1.21; P = .02) was associated with higher all-cause mortality, whereas heptadecanoic acid, 17:0, tended to be associated with lower all-cause mortality (HR, 0.89; 95% CI, 0.79-1.00; P = .05). Arachidonic:linoleic acid ratio was associated with both cardiovascular (HR, 1.15; 95% CI, 1.05-1.31; P = .04) and all-cause (HR, 1.13; 95% CI, 1.04-1.23; P = .005) mortality.
Conclusions and Relevance: Adipose tissue linoleic acid was inversely associated with all-cause mortality in elderly men, although not significantly with cardiovascular mortality.
2016. Vol. 1, no 7, 745-753 p.
Adipose tissue, Dietary fatty acids, Fatty acid composition, Insulin resistance, Insulin sensitivity