Healthful Diets and Risk of Hearing Loss

Study Overview
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Brief Summary
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To prospectively examine the relations between adherence scores for three healthful dietary patterns, the Alternate Mediterranean diet (AMED), the Dietary Approaches to Stop Hypertension (DASH), and the Alternative Healthy Eating Index (AHEI-2010), and risk of hearing loss in the Nurses' Health Study II.

Official Title
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Healthful Dietary Patterns and Risk of Hearing Loss in Women

Conditions
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Hearing Loss

Intervention / Treatment
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* Other: no intervention-this was an observational study


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: The investigators limited the study to women who provided information on their hearing on the 2009 or 2013 questionnaire. Exclusion Criteria: The investigators excluded those who did not provide responses to the hearing questions on either questionnaire, reported a hearing problem that began before baseline for the current analysis (1991) or did not report date of onset, or reported cancer other than non-melanoma skin cancer. The investigators also excluded women who did not complete the baseline diet questionnaire and who had missing diet information for each subsequent time period.

Ages Eligible for Study
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Minimum Age: 27 Years
Maximum Age: 66 Years

Sexes Eligible for Study
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Female

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Nurses' Health Study II<br>Nurses' Health Study II, an ongoing cohort study of 116,430 female registered nurses in the US, aged 25-42 at enrollment in 1989. Participants have been followed by biennial mailed questionnaires that elicit updated information on diet, lifestyle, and various health outcomes; the follow-up rate over 26 years exceeds 90% of the eligible person-time. | Other: no intervention-this was an observational study<br> <br> |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Hearing loss | The primary outcome, self-reported hearing loss that was moderate or worse in severity, was determined based on responses to the 2009 and 2013 questionnaires on which participants were asked about their hearing. On the 2009 main questionnaire, participants were asked, Do you have a hearing problem? (no, mild, moderate, severe), and At what age did you first notice a change in your hearing? On the 2013 main questionnaire, participants were asked, Which best describes your hearing? (excellent, good, a little hearing trouble, moderate hearing trouble, deaf), and Have you noticed a change in your hearing? and, if the response was Yes, At what age did you first notice a change in your hearing? | 1991-2013 | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| hearing loss in HSSQ | Detailed hearing-related information was collected electronically in 2012 supplemental questionnaire from a representative subcohort of NHS II participants (n= 33,102) with and without reported hearing problems, including information on previous evaluation for hearing loss, laterality (unilateral or bilateral), and identified causes of hearing loss (e.g. ototoxic medications, ear trauma, otosclerosis, cholesteatoma, Meniere's disease, chronic ear infection). Data from the HSSQ were used to conduct sensitivity analyses using more refined case definitions (e.g. excluding known etiologies and unilateral hearing loss). | 1991-2013 |