Table 1.
Characteristics of studies selected for inclusion in the review
| No. | Author and study population | Country | Race | Sex | Mean age at baseline (years) | No. of participants | Follow-up period (years) and person-time | End points (no. of cases) | Outcome assessment | Adjusted covariates |
|---|---|---|---|---|---|---|---|---|---|---|
| 1 | Huang et al.(25), NHANES-1 Epidemiologic Follow-up | USA | White | F | 67⋅7 | 2513 | 13⋅4; n/a | Hip fracture (130) | Self-reported hip fractures. Hip fractures were ascertained by health care records or death certificates | Height, weight, total energy intake, serum albumin, age, previous fracture history, menopausal status, parity, physical activity and frequency of alcohol use. |
| 2 | Cumming et al.(26), Study of Osteoporotic fractures | USA | White | F | 71⋅4 | 9704 | 6⋅6; n/a | Hip fracture (306) | Women were asked whether they had had a fracture and radiologic reports were reviewed, and only radiologically confirmed fractures were included | Age, clinic, weight, history of osteoporosis, history of fractures since age 50, fall in past 12 months, protein intake, caffeine intake, recreational physical activity, impaired low-frequency contrast sensitivity, estrogen replacement therapy, thiazide use, and use of calcium supplements, vitamin D supplements and Tums antacid tablets |
| 3 | Fujiwara et al.(29), Adult Health Study | Japan | Asian (Japanese) | F and M | 58⋅5 | 4573 | 14; n/a | Hip fracture (55) | Hip fracture diagnosis was made by physician based on the history of hip fracture taken at the biennial exam. Diagnosis on death certificates, medical charts and radiographs were reviewed for validation | Age, gender, BMI, milk intake, alcohol intake, age at menarche, number of children, history of vertebral fracture, self-rated health, marital status, food preference, intake of tofu, fish, coffee, tea, smoking and exposure to atomic radiation, cerebrovascular disease, paralysis, epilepsy, Parkinson's syndrome, cataract, hypo and hypertension, anaemia, hypo and hyperthyroidism |
| 4 | Meyer et al.(28), Norwegians Middle-aged adults | Norway | No information | F | 47⋅1 | 19 752 women and 20 035 men | 11⋅4; 225 285 women and 224 792 men | Hip fracture (210) | All fractures were confirmed by review of the individual medical records or discharge letters including a description of the operation | Age, height, BMI, physical activity at work and during leisure time, diabetes mellitus, disability pension, marital status, smoking and total energy intake |
| 5 | Benetou et al.(18), EPIC Elderly Network on Ageing and Health | Europe | No information | M and F | 64⋅8 | 29 122 | 8; 243 330 | Hip fracture (275) | Information on hip fracture was collected through self-report, record linkage, and through hip fracture registries | Age, sex, BMI, height, education level, smoking status, physical activity at leisure, dietary supplement use, history of diabetes at enrolment and total energy intake |
| 6 | Sahni et al.(20), Framingham Offspring Study | USA | White | M and F | 55 | 3224 | 12; n/a | Hip fracture (43) | Hip fractures were reported by hospitalisation review, death review, interview at each 4-year examination | Age, sex, total energy intake, weight, height, smoking, physical activity, menopause, estrogen, alcohol, caffeine, calcium supplement use and vitamin D supplement use |
| 7 | Feart et al.(19), Three-City Study | France | No information | M and F | 76⋅7 | 1482 | 8; n/a | Hip fracture (57) | Information on hip fracture was collected through self-report at each visit | Mediterranean diet score, age, gender, physical activity, total energy intake, education level, marital status, BMI, self-reported osteoporosis, osteoporosis treatment, calcium and/or vitamin D treatment |
| 8 | Lousuebsakul-Matthews et al.(21), Adventist Health Study-2 | USA | White | M and F | 76⋅8 | 33 208 | 5⋅1; n/a | Hip fracture (305) | Hip fracture question was asked and ascertained by linking database with the National Death Index database | Fruits and vegetable intake, age, height, weight, gender, energy intake, physical activity, smoking, health status and total calcium intake |
| 9.1 | Michaelsson et al.(17), Cohort of Swedish Men and Swedish Mammography Study (replaced by updated data via personal communication) | Sweden | No information | M and F | 60⋅7 | 45 339 | 11⋅2; 534 094 | Hip fracture (1166) | Fractures events were collated using the individual personal registration number, which was used to match and identify all incident hip fracture events in the national patient registries | Age, BMI, height, total energy intake, total alcohol intake, healthy dietary pattern, calcium and vitamin D supplementation, ever use of cortisone, educational level, living alone, physical activity level, smoking, and Charlson's comorbidity index, intake of calcium, vitamin D, phosphorus, total fat, saturated fat, total protein, retinol and previous fracture history |
| 9.2 | Michaelsson et al.(16), Additional data provided by the authors, Swedish Mammography Cohort | Sweden | No information | F | 53⋅5 | 61 240 | 22 1 375 900 | Hip fracture (5827) | Fractures events were collated using the individual personal registration number, which was used to match and identify all incident hip fracture events in the national patient registries | Age, BMI, height, education, smoking (never, former, current), physical activity level (METs), living alone, total energy intake, alcohol consumption, intake of fruit and vegetables and of red and processed meat, use of antioxidant containing supplements, soured milk and yoghurt, and cheese, calcium containing supplements, ever estrogen replacement therapy, ever cortisone use |
| 10 | Sahni et al.(23), Framingham Original Cohort | USA | White | M and F | 77 | 764 | 11⋅6; n/a | Hip fracture (97) | Hip fractures were reported by interview at each examination and reported hip fractures were confirmed by review of medical records, radiographic and operative reports | Age, sex, height, weight, total energy intake, current smoking, physical activity, current estrogen use in women, calcium supplement, vitamin D supplement and multivitamin supplement use |
| 11.1 | D Feskanich et al.(24), Health Professionals Follow-up Study, additional data provided by the authors | USA | White | M | 57⋅7 | 43 306 | 17⋅5; 383 784 | Hip fracture (694) | Self-reported fracture incidents. No validation study among men | Age, follow-up cycle, total energy intake, intakes of calcium, vitamin D and retinol from supplements, frequencies of meat, fish, egg and soda consumption, intakes of vitamin K, caffeine and alcohol, milk consumption during teenage years, BMI, height, physical activity, smoking, use of thiazide diuretics, furosemide-type diuretics and oral steroids, and diagnoses cancer, diabetes and cardiovascular disease; milk, yoghurt and cheese were also adjusted for one another |
| 11.2 | D Feskanich et al.(24), Nurses’ Health Study, additional data provided by the authors | USA | White | F | 53⋅6 | 80 600 | 20⋅8; 837 285 | Hip fracture (2138) | Self-reported fracture incidents. Validation study was conducted previously for self-reported fractures among nurses | Age, follow-up cycle, total energy intake, intakes of calcium, vitamin D and retinol from supplements, frequencies of meat, fish, egg and soda consumption, intakes of vitamin K, caffeine and alcohol, milk consumption during teenage years, BMI, height, physical activity, smoking, use of postmenopausal hormones, use of thiazide diuretics, furosemide-type diuretics and oral steroids, and diagnoses cancer, diabetes and cardiovascular disease; milk, yoghurt and cheese were also adjusted for one another |
| 12 | Bergholdt et al.(22) | Denmark | White | M and F | 57 | 73 715 | 5⋅5; n/a | Hip fracture (686) | Occurrence of hip fracture was obtained from the National Danish Patient Registry and the National Danish Causes of Death Registry | Sex, age, physical activity at work, physical activity in leisure time, alcohol intake, smoking status, educational level and BMI |
| 13.1 | Holvik et al.(30) | Norwegian Counties Study | No information | M and F | 50 | 35 114 | 25; 613 017 | Hip fracture (1865) | Hip fractures were identified by linkage to the NOREPOS hip fracture database (NORHip) | Sex, county, BMI, smoking, height, number of self-reported chronic diseases, use of vitamin supplement, use of cod liver oil supplement, physical inactivity, marital status, energy intake and education |
| 13.2 | Holvik et al.(30) | Five Counties Study, Norway | No information | M and F | 66 | 23 298 | 25; 252 991 | Hip fracture (1466) | Hip fractures were identified by linkage to the NOREPOS hip fracture database (NORHip) | Sex, county, BMI, smoking, height, number of self-reported diseases, use of any vitamin or mineral supplement, use of cod liver oil supplement, use of acid suppressing drugs, marital status, self-rated health, physical inactivity and education |