title: Association between phthalate exposure and lower handgrip strength in an elderly population: a repeated-measures study.
abstract: Decreased muscle strength can lead to adverse health outcomes in the elderly. A potential association between phthalate exposure and muscle strength was suggested previously, but has not been investigated directly. We hypothesized that phthalate exposure is associated with lower handgrip strength and that the association is modified by the dietary omega-6 to omega-3 ratio.
  
  
  
  We analyzed 1,228 participants (≥60 years of age) recruited in Seoul and Asan, Republic of Korea. The study participants were surveyed up to three times between 2012 and 2015. At every survey, we collected urine samples and measured handgrip strength twice for each hand. The associations between urine phthalate metabolite concentrations and handgrip strength were evaluated using linear mixed models. Based on dietary information from 391 individuals who participated in the first survey in Seoul, we evaluated the heterogeneity of the association for those with high and low omega-6 to omega-3 ratios, using 8.81 (the 75th quantile) as a cutoff value.
  
  
  
  Log-transformed creatinine-adjusted concentrations of mono-(2-ethyl-5-oxohexyl phthalate (MEOHP), mono-(2-ethyl-5-hydroxyhexyl) phthalate (MEHHP), and mono-n-butyl phthalate (MnBP) were inversely associated with all measured handgrip strengths (β = -0.69 to -0.42, all p-values < 0.05). Associations between phthalate biomarkers and handgrip strength did not differ by sex. When the dietary subgroup was stratified by the omega-6 to omega-3 ratio, the associations were stronger among participants with high ratios.
  
  
  
  We found inverse associations between phthalate biomarkers and handgrip strength in the elderly; this association was modified by the dietary omega-6 to omega-3 ratio.
authors: Department of Preventive Medicine, Seoul National University College of Medicine, 28 Yongon-Dong, Chongno-Gu, Seoul, Republic of Korea.|Public Health Medical Service, Seoul National University Hospital, Seoul, Republic of Korea.
authors: Kyoung-Nam
authors: KN
authors: Kim
authors: Department of Preventive Medicine, Seoul National University College of Medicine, 28 Yongon-Dong, Chongno-Gu, Seoul, Republic of Korea.
authors: Mee-Ri
authors: MR
authors: Lee
authors: Department of Preventive Medicine, Gachon University Graduate School of Medicine, Incheon, Republic of Korea.
authors: Yoon-Hyeong
authors: YH
authors: Choi
authors: Department of Food and Nutrition, Research Center for Human Ecology, College of Human Ecology, Kyung Hee University, Seoul, Republic of Korea.
authors: Hyojung
authors: H
authors: Hwang
authors: Department of Food and Nutrition, Research Center for Human Ecology, College of Human Ecology, Kyung Hee University, Seoul, Republic of Korea.
authors: Se-Young
authors: SY
authors: Oh
authors: Environmental Health Research Division, Environmental Health Research Department, National Institute of Environmental Research, Incheon, Republic of Korea.
authors: ChoongHee
authors: C
authors: Park
authors: Department of Preventive Medicine, Seoul National University College of Medicine, 28 Yongon-Dong, Chongno-Gu, Seoul, Republic of Korea. ychong1@snu.ac.kr.|Institute of Environmental Medicine, Seoul National University Medical Research Center, Seoul, Republic of Korea. ychong1@snu.ac.kr.|Environmental Health Center, Seoul National University College of Medicine, Seoul, Republic of Korea. ychong1@snu.ac.kr.
authors: Yun-Chul
authors: YC
authors: Hong
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D004032:Diet; D004781:Environmental Exposure / Q000009:adverse effects / Q000032:analysis; D004785:Environmental Pollutants / Q000652:urine*; D005260:Female; D018737:Hand Strength; D006801:Humans; D008297:Male; D008875:Middle Aged; D010795:Phthalic Acids / Q000652:urine*; D056910:Republic of Korea
chemical_list: D004785:Environmental Pollutants; D010795:Phthalic Acids
keywords: Elderly; Handgrip strength; Omega-6 to omega-3 ratio; Phthalate