Diet and Hip Fracture Risk in the United Kingdom Women's Cohort

Study Overview
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Brief Summary
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Hip fracture is a common serious injury in older women that reduces quality of life and can lead to premature death. In the United Kingdom, hip fractures are estimated to account for 1.5 million hospital bed days used per year due to long hospitalisation and rehabilitation periods post-surgery, costing the National Health Service over £1 billion per year. Diet can affect bone health and risk of hip fracture, with varying risks in women on specific diets, and specific foods and nutrients playing more important roles than others. Vegetarians may be at a greater risk of hip fracture than meat-eaters, and those who don't consume enough protein could be at a greater risk than those with adequate intakes. This research aims to investigate which dietary factors (and in what quantities) might predispose United Kingdom women to a greater risk of hip fracture, and which factors may be protective. The purpose of this study is to better understand the role of diet in reducing hip fracture risk in United Kingdom women. The research will use existing dietary and lifestyle data from the United Kingdom Women's Cohort Study and hospital records of hip fractures.

Detailed Description
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Background: Hip fracture is an increasingly prevalent global health condition that increases morbidity and mortality. Previous observational studies have shown potential for risk reduction through diet modification, but associations between many dietary factors and hip fracture incidence are uncertain, and evidence in United Kingdom populations is limited. Therefore, this study aims to assess associations between diet and hip fracture incidence in the United Kingdom Women's Cohort. Research plan and methods: The investigators will utilise dietary and lifestyle data from the United Kingdom Women's Cohort which recruited 35,372 middle-aged women between 1995-1998. This data has been linked with Hospital Episode Statistics to provide hip fracture data of participants. Cox regression models will be applied to explore potential associations between dietary factors and hip fracture incidence. Dietary factors will be modelled both as categorical and continuous so that models can be fit comparing the risk of hip fracture between categories of intakes and per increment increase in exposure intake (linear dose-response). Cubic splines will be used to model non-linear associations for dietary intake of fruits, vegetables, tea, and coffee since previous research has suggested possible non-linear associations for these variables.

Official Title
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Associations Between Diet and Hip Fracture Incidence in the United Kingdom Women's Cohort

Conditions
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Hip Fracture (First Incidence of)

Intervention / Treatment
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* Other: Dietary pattern
* Other: Fruit and vegetable intake
* Other: Meat intake
* Other: Fish intake
* Other: Egg intake
* Other: Dairy intake
* Other: Tea intake
* Other: Coffee intake
* Other: Tea and coffee intake
* Other: Protein intake
* Other: Calcium intake
* Other: Vitamin D intake


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Female Ages 35 - 69 years at time of recruitment Able to provide informed consent Exclusion Criteria: Male Not a resident of England Unable to link dietary and lifestyle data with hospital episode data Missing covariate data Hip fracture or osteoporosis prevalence before or on the date of recruitment

Ages Eligible for Study
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Minimum Age: 36 Years
Maximum Age: 69 Years

Sexes Eligible for Study
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Female

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| United Kingdom Women's Cohort<br>United Kingdom Women's Cohort Study. No interventions are to be administered in this observational prospective cohort study. | Other: Dietary pattern<br>* (regular meat-eater, occasional meat-eater, fish-eater, vegetarian, and vegan)<br>Other: Fruit and vegetable intake<br>* Intake of fruits, vegetables, fruits and vegetables combined from food frequency questionnaire<br>Other: Meat intake<br>* Red meat, poultry, processed meat from food frequency questionnaire<br>Other: Fish intake<br>* Intake of fish from food frequency questionnaire<br>Other: Egg intake<br>* Intake of eggs from food frequency questionnaire<br>Other: Dairy intake<br>* Intake of dairy products from food frequency questionnaire<br>Other: Tea intake<br>* Intake of tea (drink) from food frequency questionnaire<br>Other: Coffee intake<br>* Intake of coffee (caffeinated or decaffeinated) from food frequency questionnaire<br>Other: Tea and coffee intake<br>* Combined intake of tea and coffee from food frequency questionnaire<br>Other: Protein intake<br>* Estimated intake of protein, derived from food frequency questionnaire<br>Other: Calcium intake<br>* Estimated intake of calcium, derived from food frequency questionnaire<br>Other: Vitamin D intake<br>* Estimated intake of vitamin D, derived from food frequency questionnaire and any recorded supplemental intake<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Hip fracture incidence (first) | Incidence of first hip fracture ascertained from linkage to Hospital Episode Statistics (HES) data | age when the completed questionnaire was returned (1995-1998) until age at event, death, or end of study period (19 Mar 2019) | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Nutrition, Fracture, Cohort study, Epidemiology, Osteoporosis