Clinical trial NCT03366532: Dietary Analyses in the Nurses' Health Study, Nurses' Health Study II, and Health Professionals Follow-Up Study
Official title: Dietary Analyses in the Nurses' Health Studies and Health Professionals Follow-Up Study (Diabetes, Cardiovascular Disease, and Mortality)
Study type: OBSERVATIONAL
Overall status: COMPLETED
Conditions: Type2 Diabetes
Coronary Artery Disease
Morality
Stroke
Keywords: diet
food frequency questionnaire
nutrient
Lead sponsor: Harvard School of Public Health (HSPH)
Sponsor class: OTHER
Collaborators: name: Harvard Medical School (HMS and HSDM)
First posted: 2017-12-08
Enrollment: 289900
Sex: ALL
Minimum age (years): 21
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: yes
Observational model: COHORT
Time perspective: PROSPECTIVE
Sampling method: NON_PROBABILITY_SAMPLE
Study population: The Nurses' Health Study (NHS) consisted of 121,700 female registered nurses enrolled in 1976. The NHSII was initiated in 1989 with the recruitment of 116,671 younger female registered nurses. The Health Professionals Follow-up Study (HPFS) was established in 1986 and was comprised of 51,529 US male health professionals.

Brief summary: To determine the relationships of a variety of nutrients, foods, and dietary patterns with the subsequent risk of developing type 2 diabetes, cardiovascular disease, and mortality in US men and women.

Detailed description: The Nurses' Health Study (NHS) consisted of 121,700 female registered nurses aged 30 to 55 years from 11 US states who were enrolled in 1976. The NHSII was initiated in 1989 with the recruitment of 116,671 younger female registered nurses, 24 to 44 years of age, from 14 states. The Health Professionals Follow-up Study (HPFS) was established in 1986 and was comprised of 51,529 US male health professionals ranging in age from 40 to 75 years at enrollment from 50 states.

Study investigators sent follow-up questionnaires biennially to participants to update information on past medical history as well as lifestyle factors. Validated food frequency questionnaires (FFQs) were first sent in 1980 for the NHS, 1991 for the NHSII, and 1986 for the HPFS. Dietary assessments have been updated every 2-4 years since baseline. The FFQs collect information on average intake of each food item over the past year. It also specifies a common serving size for each item. Participants could select from one of nine intake frequency choices, ranging from less than once per month to six or more times per day. Participants also provided information on current use and dose of multivitamins and use of other vitamin supplements.

For these three cohorts, investigators repeatedly collected and updated information on several anthropometric and lifestyle factors such as weight, smoking status, alcohol use, coffee intake, and physical activity level. Information was also collected on several major risk factors.

Study subjects reported new diagnoses biennially. After obtaining permission from participants, their medical and pathological records were acquired. Study physicians blinded to questionnaire information reviewed these records to confirm diagnoses of coronary heart disease and stroke. Self-reported diabetes diagnoses are confirmed using a validated supplementary questionnaire on symptoms, blood glucose levels, and medication use. Deaths are identified through reports from next of kin, postal authorities, or by searching the National Death Index.

All investigations regarding dietary factors in relation to type 2 diabetes, cardiovascular disease, and mortality have been approved by the institutional review boards of both Brigham and Women's Hospital and Harvard T.H Chan School of Public Health.

Eligibility criteria: Inclusion Criteria:

* Returned baseline food frequency questionnaires (FFQs).

Exclusion Criteria:

* Participants who had died or reported a diagnosis of diabetes (including type 1 diabetes, type 2 diabetes, and gestational diabetes for women), cardiovascular disease (CVD) or cancer at and before the baseline for the dietary analyses.
* Participants who left more than 70 of the 131 food items blank on the baseline FFQ, reported unusual total energy intake levels (\<3,347 or \>17,573 kJ/day for men, and \<2,092 or \>14,644 kJ/day for women), or had missing baseline dietary information.
* Participants who only completed the baseline questionnaire.

Primary outcomes:
measure: Type 2 diabetes
timeFrame: Since 1976, with active follow-up
measure: Cardiovascular disease
timeFrame: Since 1976, with active follow-up
measure: Mortality
timeFrame: Since 1976, with active follow-up
Secondary outcomes:
Other outcomes:
Locations:
Study officials:
References:
citation: Belanger CF, Hennekens CH, Rosner B, Speizer FE. The nurses' health study. Am J Nurs. 1978 Jun;78(6):1039-40. No abstract available.
citation: Rimm EB, Giovannucci EL, Willett WC, Colditz GA, Ascherio A, Rosner B, Stampfer MJ. Prospective study of alcohol consumption and risk of coronary disease in men. Lancet. 1991 Aug 24;338(8765):464-8. doi: 10.1016/0140-6736(91)90542-w.
citation: Ma L, Liu G, Sampson L, Willett WC, Hu FB, Sun Q. Dietary glucosinolates and risk of type 2 diabetes in 3 prospective cohort studies. Am J Clin Nutr. 2018 Apr 1;107(4):617-625. doi: 10.1093/ajcn/nqy003.