Analytical analyses
To examine relationships between diet and coronary arrest, we put Cox proportional dangers models stratified of the many years (mo) and you may go after-upwards course to help you imagine RRs and you can 95% CIs. People had been split up into quintiles of collective mediocre intake regarding magnesium, potassium, and you will calcium supplements to minimize the inside-people variation and best depict a lot of time-label intake ( 18). A blended mineral eating plan rating out-of magnesium, potassium, and you can calcium supplements was basically determined by the delegating what to for each and every quintile and you will summing the fresh new affairs. Users regarding lowest quintile (quintile step 1) from magnesium, potassium, or calcium intake obtained 1 area for every nutrient, players in the next quintile (quintile 2) gotten dos factors, an such like. Collective averages have been determined if you take the new suggest of the many advertised FFQ consumption as much as the start of each dos-y realize-upwards interval. The fresh cumulative mediocre consumption was used to https://datingranking.net/std-dating-sites/ help you expect heart attack frequency of the full time of the past came back survey before next go after-up duration.
Multivariate patterns were adjusted having years (mo) and you will schedule big date (2-y date menstruation) and integrated consumption out-of overall time (kcal), alcoholic drinks (g/d), smoking, Body mass index, physical exercise, parental reputation for early myocardial infarction, postmenopausal hormonal medication fool around with, thiazide fool around with, aspirin play with, multi vitamin have fun with, and reputation of all forms of diabetes, blood pressure, and hypercholesterolemia at the baseline. To check on to possess an effective linear trend, i tasked for each and every quintile this new average well worth and you can modeled so it adjustable since an ongoing varying. We checked the possibility deviation of linearity that with a chances proportion attempt having investigations of a model on the linear identity that have a product including the linear label along with limited cubic spline transformations ( 19). We along with conducted analyses that provided most of the step three minerals while doing so. Magnesium and potassium consumption had been very correlated (r = 0.79 in the NHS We; r = 0.73 throughout the NHS II), and correlations ranging from calcium supplements and you will potassium consumption (roentgen = 0.44 on the NHS We; r = 0.41 in the NHS II), whereas ranging from calcium supplements and you may magnesium consumption (roentgen = 0.54 about NHS We; roentgen = 0.56 throughout the NHS II) was reasonable. The fresh Q decide to try was applied to check into the heterogeneity ranging from the new NHS I and NHS II. RRs (±SEs) for every quintile of for each cohort was pooled when you look at the fixed-consequences designs so you’re able to assess bottom line estimates ( 20). Likewise, the upgraded meta-study followed fundamental routine ( 20) away from research to own heterogeneity utilising the Q make sure playing with repaired effects model to help make summary quotes whenever no anywhere between-degree heterogeneity try clear; or even an arbitrary-effects design was used.
To examine the potential effect modification of the association between dietary minerals and stroke risk by age, hypertension, and diabetes, we stratified our multivariate model on age (<60 compared with ?60 y), hypertension (yes compared with no), and diabetes (yes compared with no) and separately tested the significance of an interaction by using a likelihood ratio test for the comparison of the model with interaction terms to the model with only main effects. All P values were 2-sided, and analyses were conducted with SAS 9.2 software (SAS Institute Inc.).
Abilities
During the 31 y from pursue-right up out-of 1980 through 2010 from the NHS We and you may 22 y off go after-upwards off 1989 due to 2011 regarding the NHS II, a total of 3780 experience coronary arrest cases was basically determined. Of these circumstances, 3237 incident strokes was in fact recorded regarding NHS We (together with 1664 ischemic, 544 hemorrhagic, and 1029 unspecified shots), and 543 experience shots was noted in the NHS II (and additionally 186 ischemic, ninety-five hemorrhagic, and you will 265 unspecified strokes). Age-standardized attributes out of data users in the midpoint during the follow-right up during the 1994 for the NHS I as well as in 1995 getting the brand new NHS II are offered during the Dining table 1. Women with high nutrient consumption was basically expected to play with aspirin, vitamins, and you will postmenopausal hormones treatment, a whole lot more privately energetic, less likely to want to end up being latest cigarette smokers than have been girls with straight down nutrient consumption. Study for ladies on the NHS I and you can NHS II was basically mutual while the i failed to to see a life threatening anywhere between-investigation heterogeneity (Q-statistic P > 0.05).