Primary Research · 2017
Menaquinone-7 supplementation improves arterial stiffness in healthy postmenopausal women
Knapen et al. · Thrombosis and Haemostasis, 2017
Key finding
180mcg/day MK-7 for 3 years significantly improved arterial stiffness in postmenopausal women.
Abstract
PubMed · PMID 28440744 →BACKGROUND: We aimed to quantify the time to diagnosis among women with endometriosis in the United States (US) and to identify patient- and physician-related factors affecting diagnostic delay. PATIENTS AND METHODS: An online cross-sectional survey was conducted from August 6, 2012, through November 14, 2012. Respondents aged 18-49 years who reported a physician's diagnosis/suspicion of endometriosis within the previous 10 years were included. Endometriosis-related symptoms and diagnostic history were captured and summarized. Univariate analyses identified factors associated with time from symptom onset to first consultation and from first consultation to diagnosis. RESULTS: Of 638 respondents included, most (56%) reported seeking care for at least one of the following symptoms: menstrual pain (31.6%), nonmenstrual pain (27.3%), and pain during sex (7.5%). Most diagnoses (84%) were made by obstetricians/gynecologists; 49% of diagnoses were surgical versus 51% nonsurgical. Mean time from symptom onset to diagnosis was 4.4 years. Mean time to first consultation was shorter among women aged 40-49 years versus those aged <18 years (14.2 vs. 43.5 months; p < 0.0001) and those consulting for symptoms versus routine/other care (27.9, 24.9, and 28.4 months for menstrual pain, nonmenstrual pain, and pain during sex, respectively, vs. 61.4 months; all p < 0.01). Mean time from first consultation to diagnosis was shorter among women aged 40-49 years versus those aged <18 years (12.4 vs. 34.5 months; p = 0.0009) and those diagnosed by obstetricians/gynecologists versus nonobstetricians/gynecologists (21.5 vs. 40.3 months; p = 0.041). CONCLUSIONS: Time to endometriosis diagnosis appears to have shortened in the US. Better patient and physician education regarding symptomatology may contribute to further gains.
Abstract sourced from PubMed, a database of the U.S. National Library of Medicine. Displayed in the authors’ own words for context; our critique is in the sections below.
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The same questions worth asking about any research paper, not just this one. Worth a minute even if you trust the grade.
Who was studied, and do you resemble them?
Supplement effects often depend on baseline status. Vitamin D helps people who are deficient; iron helps people who are anemic. A result in people unlike you may not apply to you.
What was measured, and does it matter in daily life?
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How large was the effect — not just whether it was significant.
'Statistically significant' only means the effect is unlikely to be zero. It doesn't tell you the effect is large enough to notice. Look for effect sizes, not just p-values.
Who paid for the trial, and what did they stand to gain?
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Has anyone else replicated this?
Single positive trials are hypotheses. Replication by independent groups is what turns a hypothesis into reliable evidence. If the only positive trial is the one you're reading, wait.
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