Nicola Veronese1,2, Brendon Stubbs3,4,5, Ai Koyanagi6, Alberto Vaona7, Jacopo Demurtas8, Patricia Schofield5, Trevor Thompson9, Stefania Maggi10. 1. National Research Council, Neuroscience Institute, Aging Branch, Padova, Italy. ilmannato@gmail.com. 2. Ambulatory of Nutrition, IRCCS "S. de Bellis", National Institute of Gastroenterology-Research Hospital, Castellana Grotte, Bari, Italy. ilmannato@gmail.com. 3. South London and Maudsley NHS Foundation Trust, London, UK. 4. Institute of Psychiatry, Psychology and Neuroscience (IoPPN), King's College London, London, UK. 5. Faculty of Health, Social Care and Education, Anglia Ruskin University, Chelmsford, UK. 6. Research and Development Unit, Parc Sanitari Sant Joan de Déu, Fundació Sant Joan de Déu, CIBERSAM, Sant Boi de Llobregat, Barcelona, Spain. 7. Primary Care Department, Azienda ULSS20 Verona, Verona, Italy. 8. Primary Care Department, Azienda USL Toscana Sud Est, Grosseto, Italy. 9. Faculty of Education and Health, University of Greenwich, London, UK. 10. National Research Council, Neuroscience Institute, Aging Branch, Padova, Italy.
Abstract
BACKGROUND/ OBJECTIVES: A small number of case-control studies have suggested that mitochondrial haplogroups could be associated with obesity. We examined whether obesity risk was influenced by mitochondrial haplogroup in a large North American cohort across an 8-year period. We conducted a longitudinal cohort study including individuals from the Osteoarthritis Initiative. SUBJECTS/ METHODS: Mitochondrial haplogroups were determined by sequencing and PCR-RFLP techniques using this nomenclature: HV, JT, KU, IWX, and super HV/others. The strength of the association between mitochondrial haplogroups and incident obesity was quantified with hazard ratios (HRs), adjusted for potential confounders using a Cox's regression analysis. RESULTS: Overall, 2342 non-obese Caucasian participants (56.7% women) with a mean ± SD age of 62.0 ± 9.5 years at baseline were included. During a median follow-up of 8 years, 334 individuals ( = 14.3% of baseline population) became obese. After adjusting for nine potential confounders, the haplogroups IWX carried a significant 48% higher risk of obesity (HR = 1.48; 95% CI: 1.02-2.39) compared to the HV haplotype (the most frequent type). CONCLUSION: Only the presence of the IWX haplogroups appears to be linked to increased obesity risk, independent of potential baseline confounders. Future cohort studies are needed to confirm these findings and to determine potential underlying mechanisms.
BACKGROUND/ OBJECTIVES: A small number of case-control studies have suggested that mitochondrial haplogroups could be associated with obesity. We examined whether obesity risk was influenced by mitochondrial haplogroup in a large North American cohort across an 8-year period. We conducted a longitudinal cohort study including individuals from the Osteoarthritis Initiative. SUBJECTS/ METHODS: Mitochondrial haplogroups were determined by sequencing and PCR-RFLP techniques using this nomenclature: HV, JT, KU, IWX, and super HV/others. The strength of the association between mitochondrial haplogroups and incident obesity was quantified with hazard ratios (HRs), adjusted for potential confounders using a Cox's regression analysis. RESULTS: Overall, 2342 non-obese Caucasian participants (56.7% women) with a mean ± SD age of 62.0 ± 9.5 years at baseline were included. During a median follow-up of 8 years, 334 individuals ( = 14.3% of baseline population) became obese. After adjusting for nine potential confounders, the haplogroups IWX carried a significant 48% higher risk of obesity (HR = 1.48; 95% CI: 1.02-2.39) compared to the HV haplotype (the most frequent type). CONCLUSION: Only the presence of the IWX haplogroups appears to be linked to increased obesity risk, independent of potential baseline confounders. Future cohort studies are needed to confirm these findings and to determine potential underlying mechanisms.