title: Dietary protein intake is associated with better physical function and muscle strength among elderly women.
abstract: Dietary protein intake might be beneficial to physical function (PF) in the elderly. We examined the cross-sectional and prospective associations of protein intake of g/kg body weight (BW), fat mass (FM) and lean mass (LM) with PF in 554 women aged 65·3-71·6 years belonging to the Osteoporosis Risk Factor and Prevention Fracture Prevention Study. Participants filled a questionnaire on lifestyle factors and 3-d food record in 2002. Body composition was measured by dual-energy X-ray absorptiometry, and PF measures were performed at baseline and at 3-year follow-up. Sarcopaenia was defined using European Working Group on Sarcopenia in Older People criteria. At the baseline, women with higher protein intake (≥ 1·2 g/kg BW) had better performance in hand-grip strength/body mass (GS/BM) (P=0·001), knee extension/BM (P=0·003), one-leg stance (P=0·047), chair rise (P=0·043), squat (P=0·019), squat to the ground (P=0·001), faster walking speed for 10 m (P=0·005) and higher short physical performance battery score (P=0·004) compared with those with moderate and lower intakes (0·81-1·19 and ≤ 0·8 g/kg BW, respectively). In follow-up results, higher protein intake was associated with less decline in GS/BM, one-leg stance and tandem walk for 6 m over 3 years. Overall, results were no longer significant after controlling for FM. Associations were detected between protein intake and PF in non-sarcopaenic women but not in sarcopaenic women, except for change of GS (P=0·037). Further, FM but not LM was negatively associated with PF measures (P<0·050). This study suggests that higher protein intake and lower FM might be positively associated with PF in elderly women.
authors: 1Institute of Public Health and Clinical Nutrition,University of Eastern Finland,PO Box 1627,FI70211 Kuopio,Finland.
authors: Masoud
authors: M
authors: Isanejad
authors: 1Institute of Public Health and Clinical Nutrition,University of Eastern Finland,PO Box 1627,FI70211 Kuopio,Finland.
authors: Jaakko
authors: J
authors: Mursu
authors: 2Department of Orthopaedics and Traumatology,Kuopio University Hospital,Building 3,PO Box 100,FIN-70290,Kuopio,Finland.
authors: Joonas
authors: J
authors: Sirola
authors: 2Department of Orthopaedics and Traumatology,Kuopio University Hospital,Building 3,PO Box 100,FIN-70290,Kuopio,Finland.
authors: Heikki
authors: H
authors: Kröger
authors: 3Kuopio Musculoskeletal Research Unit,University of Eastern Finland,FIN-70211 Kuopio,Finland.
authors: Toni
authors: T
authors: Rikkonen
authors: 4Department of Obstetrics and Gynaecology,Kuopio University Hospital,PO Box 1777,FIN-70211,Kuopio,Finland.
authors: Marjo
authors: M
authors: Tuppurainen
authors: 1Institute of Public Health and Clinical Nutrition,University of Eastern Finland,PO Box 1627,FI70211 Kuopio,Finland.
authors: Arja T
authors: AT
authors: Erkkilä
mesh_terms: D000368:Aged; D000375:Aging / Q000502:physiology*; D001823:Body Composition; D003430:Cross-Sectional Studies; D004032:Diet; D004044:Dietary Proteins / Q000008:administration & dosage*; D005260:Female; D050723:Fractures, Bone / Q000517:prevention & control; D018737:Hand Strength; D006801:Humans; D008019:Life Style; D053580:Muscle Strength / Q000502:physiology*; D010024:Osteoporosis / Q000517:prevention & control*; D010809:Physical Fitness / Q000502:physiology*; D011446:Prospective Studies; D012307:Risk Factors; D055948:Sarcopenia / Q000175:diagnosis / Q000503:physiopathology; D011795:Surveys and Questionnaires
chemical_list: D004044:Dietary Proteins
keywords: BM body mass; BW body weight; Dietary protein intake; Elderly women; FM fat mass; GS hand-grip strength; LM lean mass; MS muscle strength; Muscle strength; PF physical function; Physical function; RSMI relative skeletal muscle index; SPPB short physical performance battery; Sarcopaenia; WS walking speed