多不饱和脂肪有助于降低老年男性全因死亡率，而非心血管疾病死亡率
2016年8月17日，《美国医学会杂志·心脏病学分册》在线发表瑞典乌普萨拉大学、达拉纳大学的研究报告，发现皮下脂肪组织的ω-6亚油酸与中老年男子随后15年的全因死亡率降低有相关性，多不饱和脂肪酸摄入量过低可增加过早死亡的风险。但是，未见与心血管疾病死亡率显著相关性。
该研究根据乌普萨拉成年男子纵向研究（ULSAM），对853位71岁男性的脂肪组织活检标本和血样进行了分析。约在同一时间，研究男性被要求在7天内填写食物日记。许多人低估了他们的能量和脂肪的摄入。
结果发现，脂肪组织的多不饱和脂肪酸比例反映了个体脂肪酸长期摄入量，而对于亚油酸似乎更是如此，这是最常见的多不饱和脂肪酸。然而，该研究显示ω-3脂肪酸与心血管疾病或死亡风险无显著相关性。
在考虑某些已知心血管疾病危险因素后，未观察到任何脂肪酸与心血管疾病有显著相关性（在15年随访期间251例死于心血管疾病，风险比：0.92～1.05，P≥0.27）。
然而，对于总死亡率（605例死亡），发现脂肪组织亚油酸比例较高，与死亡风险降低10%有相关性（风险比：0.90，P=0.02），并且直接与摄入量强烈相关（P＜0.001）。二次分析发现棕榈油酸与全因死亡率正相关（风险比：1.11，P=0.02），十七烷酸与全因死亡率临界负相关（风险比：0.89，P=0.05），花生四烯酸∶亚油酸比值与心血管死亡率（风险比：1.15，P=0.04）和全因死亡率（风险比：1.13，P=0.005）均正相关。
因此，脂肪组织亚油酸与老年男性全因死亡率呈负相关，但是与心血管疾病死亡率无显著相关性。
JAMA Cardiol. 2016 Aug 17. [Epub ahead of print]
Association of Adipose Tissue Fatty Acids With Cardiovascular and All-Cause Mortality in Elderly Men.
Iggman D, Arnlov J, Cederholm T, Risérus U.
Uppsala University, Uppsala, Sweden; Center for Clinical Research Dalarna, Falun, Sweden; Dalarna University, Falun, Sweden.
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.
PMID: 27541681
DOI: 10.1001/jamacardio.2016.2259
