Heavier smoking may lead to a relative increase in waist circumference: evidence for a causal relationship from a Mendelian randomisation meta-analysis. The CARTA consortium: Table 1

Morris, R. W. et al. (2015) Heavier smoking may lead to a relative increase in waist circumference: evidence for a causal relationship from a Mendelian randomisation meta-analysis. The CARTA consortium: Table 1. BMJ Open, 5(8), e008808. (doi: 10.1136/bmjopen-2015-008808) (PMID:26264275) (PMCID:PMC4538266)

Abstract

Objectives: To investigate, using a Mendelian randomisation approach, whether heavier smoking is associated with a range of regional adiposity phenotypes, in particular those related to abdominal adiposity. Design: Mendelian randomisation meta-analyses using a genetic variant (rs16969968/rs1051730 in the CHRNA5-CHRNA3-CHRNB4 gene region) as a proxy for smoking heaviness, of the associations of smoking heaviness with a range of adiposity phenotypes. Participants: 148 731 current, former and never-smokers of European ancestry aged ≥16 years from 29 studies in the consortium for Causal Analysis Research in Tobacco and Alcohol (CARTA). Primary outcome measures Waist and hip circumferences, and waist-hip ratio. Results: The data included up to 66 809 never-smokers, 43 009 former smokers and 38 913 current daily cigarette smokers. Among current smokers, for each extra minor allele, the geometric mean was lower for waist circumference by −0.40% (95% CI −0.57% to −0.22%), with effects on hip circumference, waist-hip ratio and body mass index (BMI) being −0.31% (95% CI −0.42% to −0.19), −0.08% (−0.19% to 0.03%) and −0.74% (−0.96% to −0.51%), respectively. In contrast, among never-smokers, these effects were higher by 0.23% (0.09% to 0.36%), 0.17% (0.08% to 0.26%), 0.07% (−0.01% to 0.15%) and 0.35% (0.18% to 0.52%), respectively. When adjusting the three central adiposity measures for BMI, the effects among current smokers changed direction and were higher by 0.14% (0.05% to 0.22%) for waist circumference, 0.02% (−0.05% to 0.08%) for hip circumference and 0.10% (0.02% to 0.19%) for waist-hip ratio, for each extra minor allele. Conclusions: For a given BMI, a gene variant associated with increased cigarette consumption was associated with increased waist circumference. Smoking in an effort to control weight may lead to accumulation of central adiposity.

• Item Type: Articles
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: McConnachie, Professor Alex and Padmanabhan, Professor Sandosh and Watt, Professor Graham and Sattar, Professor Naveed and Ford, Professor Ian
• Authors: Morris, R. W., Taylor, A. E., Fluharty, M. E., Bjørngaard, J. H., Åsvold, B. O., Elvestad Gabrielsen, M., Campbell, A., Marioni, R., Kumari, M., Korhonen, T., Männistö, S., Marques-Vidal, P., Kaakinen, M., Cavadino, A., Postmus, I., Husemoen, L. L. N., Skaaby, T., Ahluwalia, T. V. S., Treur, J. L., Willemsen, G., Dale, C., Wannamethee, S. G., Lahti, J., Palotie, A., Räikkönen, K., McConnachie, A., Padmanabhan, S., Wong, A., Dalgård, C., Paternoster, L., Ben-Shlomo, Y., Tyrrell, J., Horwood, J., Fergusson, D. M., Kennedy, M. A., Nohr, E. A., Christiansen, L., Kyvik, K. O., Kuh, D., Watt, G., Eriksson, J. G., Whincup, P. H., Vink, J. M., Boomsma, D. I., Davey Smith, G., Lawlor, D., Linneberg, A., Ford, I., Jukema, J. W., Power, C., Hyppönen, E., Jarvelin, M.-R., Preisig, M., Borodulin, K., Kaprio, J., Kivimaki, M., Smith, B. H., Hayward, C., Romundstad, P. R., Sørensen, T. I. A., Munafò, M. R., and Sattar, N.
• College/School: College of Medical Veterinary and Life Sciences > School of Health & Wellbeing > Robertson Centre; College of Medical Veterinary and Life Sciences > School of Health & Wellbeing > General Practice and Primary Care; College of Medical Veterinary and Life Sciences > School of Cardiovascular & Metabolic Health
• Journal Name: BMJ Open
• Publisher: BMJ Publishing Group
• ISSN: 2044-6055
• ISSN (Online): 2044-6055
• Copyright Holders: Copyright © 2015 The Authors
• First Published: First published in BMJ Open 5(8):e008808
• Publisher Policy: Reproduced under a creative commons license