Heterogeneity of Associations between Total and Types of Fish Intake and the Incidence of Type 2 Diabetes: Federated Meta-Analysis of 28 Prospective Studies Including 956,122 Participants.

Silvia Pastorino,Tom Bishop,Hossein Poustchi,Charlotta Rylander,Huaidong Du,Tommi Härkänen,Stephen J Sharp,Jonathan E Shaw,Alicja Wolk,Atsushi Goto,Paul Knekt,Xu Lin,Zhengming Chen,Daan Kromhout,Liang Sun,Norie Sawada,Tasnime Akbaraly,Wanqing Wen,Nicholas J Wareham,Maryam Hashemian,Dianna J Magliano,Matthew Pearce,Nita G Forouhi,Ritva Järvinen,Reza Malekzadeh,Eiliv Lund,Gráinne O’Donoghue,Mika Kivimäki ,María Inês Schmidt ,Xiao‐Ou Shu ,Zheng Wang ,Joline W.j Beulens ,Natália Bordin Barbieri ,Sabita S Soedamah‐Muthu ,Donal J O'gorman ,Bruce Bartholow Duncan ,Miguel Ángel Martínez‐González ,Maira Bes–Rastrollo

doi:10.3390/nu13041223

Abstract

The association between fish consumption and new-onset type 2 diabetes is inconsistent and differs according to geographical location. We examined the association between the total and types of fish consumption and type 2 diabetes using individual participant data from 28 prospective cohort studies from the Americas (6), Europe (15), the Western Pacific (6), and the Eastern Mediterranean (1) comprising 956,122 participants and 48,084 cases of incident type 2 diabetes. Incidence rate ratios (IRRs) for associations of total fish, shellfish, fatty, lean, fried, freshwater, and saltwater fish intake and type 2 diabetes were derived for each study, adjusting for a consistent set of confounders and combined across studies using random-effects meta-analysis. We stratified all analyses by sex due to observed interaction (p = 0.002) on the association between fish and type 2 diabetes. In women, for each 100 g/week higher intake the IRRs (95% CIs) of type 2 diabetes were 1.02 (1.01–1.03, I2 = 61%) for total fish, 1.04 (1.01–1.07, I2 = 46%) for fatty fish, and 1.02 (1.00–1.04, I2 = 33%) for lean fish. In men, all associations were null. In women, we observed variation by geographical location: IRRs for total fish were 1.03 (1.02–1.04, I2 = 0%) in the Americas and null in other regions. In conclusion, we found evidence of a neutral association between total fish intake and type 2 diabetes in men, but there was a modest positive association among women with heterogeneity across studies, which was partly explained by geographical location and types of fish intake. Future research should investigate the role of cooking methods, accompanying foods and environmental pollutants, but meanwhile, existing dietary regional, national, or international guidelines should continue to guide fish consumption within overall healthy dietary patterns.

Highlights

The prevalence of type 2 diabetes has been increasing globally, and it is predicted to affect an estimated 700 million people by 2045 [1]
Since the heterogeneity of the association between fish intake and type 2 diabetes across different geographical areas was reported in previous meta-analyses [4,5,6,7,8,9,10], we further presented the results by the following geographical regions according to WHO
During follow-up ranging from 4 to 25 years, 48,084 clinically incident cases of type 2 diabetes were recorded for the primary endpoint (n = 49,410 when using the secondary outcome of type 2 diabetes incidence)

Summary

Introduction

The prevalence of type 2 diabetes has been increasing globally, and it is predicted to affect an estimated 700 million people by 2045 [1]. Fish consumption has been shown to have cardiometabolic benefits among the general population and diabetes patients [2,3]. Benefits such as improved lipid profile and reduced inflammation have been attributed to the high content of long-chain n-3 fatty acids (LCFAs) [3]. Types of fish consumed, cooking methods and levels of fish contaminants, which might vary by geographical location, are possible explanations for these heterogeneous findings and whether sex differences may exist is unresolved. Methodological issues such as variation in covariate adjustment may contribute

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Discussion

Conclusion