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George R. Merriam

Bio: George R. Merriam is an academic researcher from University of Washington. The author has contributed to research in topics: Growth hormone deficiency & Menopause. The author has an hindex of 37, co-authored 76 publications receiving 5411 citations. Previous affiliations of George R. Merriam include Washington University in St. Louis & University of Colorado Boulder.


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Journal ArticleDOI
TL;DR: GH therapy offers benefits in body composition, exercise capacity, skeletal integrity, and quality of life measures and is most likely to benefit those patients who have more severe GHD, and the risks associated with GH treatment are low.
Abstract: Growth hormone treatment can provide benefits in body composition, bone, and quality of life in adults with confirmed growth hormone deficiency.

881 citations

Journal ArticleDOI
TL;DR: In the EFP and ELP, the frequency of gonadotropin pulsations is reduced at night in association with sleep, and a progressive reduction of LH pulse frequency and amplitude occurs during the LP which is correlated with the duration of exposure of the hypothalamic-pituitary axis to progesterone.
Abstract: To characterize the spectrum of pulsatile gonadotropin secretion during the course of the normal menstrual cycle, we studied normal women during 51 ovulatory cycles. Plasma gonadotropin concentrations were measured at 10-min intervals for 20-24 h during the early, mid-, and late follicular phases and the early, mid-, and late luteal phases. LH data series were analyzed using 2 different computer-assisted algorithms for pulse detection. The LH interpulse interval decreased during the follicular phase (FP) from 94 +/- 4 (+/- SEM) min in the early FP (EFP) to 71 +/- 4 min by the late FP (LFP; P less than 0.001). The estimation of LH pulse frequency in the EFP was significantly affected by slowing of episodic LH secretion during sleep. In the luteal phase (LP), the LH interpulse interval progressively increased from 103 +/- 8 min in the early LP (ELP) to 216 +/- 39 min by the late LP (LLP; P less than 0.001). Sleep-associated slowing of episodic LH secretion also occurred in the ELP. The mean LH pulse amplitude in the EFP (6.5 +/- 0.4 mIU/ml) decreased significantly by the midfollicular phase (MFP; 5.1 +/- 0.8 mIU/ml; P less than 0.05) and increased once again by the LFP (7.2 +/- 1.2 mIU/ml). LH pulse amplitude was highest in the ELP (14.9 +/- 1.7 mIU/ml), decreased by the midluteal phase (MLP) to 12.2 +/- 2.0 mIU/ml, and declined further by the LLP to 7.6 +/- 1.1 mIU/ml (P less than 0.001 vs. ELP). FSH secretion was significantly (P less than 0.05) correlated with LH secretion at time lags of 0-10 min in 82% of the studies. These results indicate the following. 1) In the EFP and ELP, the frequency of gonadotropin pulsations is reduced at night in association with sleep. 2) The frequency of LH secretion increases from the EFP to MFP and LFP. 3) LH pulse amplitude decreases in the MFP, suggesting enhanced negative feedback of estrogen on the hypothalamic-pituitary axis and/or a decrease in GnRH secretion at this stage. 4) A progressive reduction of LH pulse frequency and amplitude occurs during the LP which is correlated with the duration of exposure of the hypothalamic-pituitary axis to progesterone. 5) A close relationship exists between secretion of LH and FSH, suggesting a common stimulatory factor for both gonadotropins.

451 citations

Journal ArticleDOI
TL;DR: The rationale that earlier intervention than that performed in the WHI and HERS trials will provide cardiovascular benefit to women is the driving force behind the Kronos Early Estrogen Prevention Study, or KEEPS.
Abstract: Observational studies have indicated that hormone therapy given at or after menopause is linked to substantial reduction in cardiovascular disease and its risk factors. Recent findings from the Women's Health Initiative (WHI) clinical trial, however, indicate that combined estrogen plus progestin hormone therapy, as well as estrogen-alone hormone therapy (given to women without a uterus), is ineffective in preventing the new onset of cardiac events in previously healthy late menopausal women. Further, the secondary prevention trial, the Heart and Estrogen/progestin Replacement Study (HERS), also failed to demonstrate any benefit of initiation of hormone therapy in women with established coronary heart disease. In light of these results, a hypothesis has arisen that early initiation of hormone therapy, in women who are at the inception of their menopause, will delay the onset of subclinical cardiovascular disease in women. The rationale that earlier intervention than that performed in the WHI and HERS trials will provide cardiovascular benefit to women is the driving force behind the Kronos Early Estrogen Prevention Study, or KEEPS. KEEPS is a multicenter, 5-year clinical trial that will evaluate the effectiveness of 0.45 mg of conjugated equine estrogens, 50 microg weekly transdermal estradiol (both in combination with cyclic oral, micronized progesterone, 200 mg for 12 days each month), and placebo in preventing progression of carotid intimal medial thickness and the accrual of coronary calcium in women aged 42-58 years who are within 36 months of their final menstrual period. A total of 720 women are planned to be enrolled in 2005, with an anticipated close-out of the trial in 2010. This overview summarizes the recruitment and methodology of the KEEPS trial.

394 citations

Journal ArticleDOI
TL;DR: This research highlights the need to understand more fully the role of Epstein-Barr virus in the development of type 2 diabetes and its role in the immune system.
Abstract: Northwestern University Feinberg School of Medicine (M.E.M.), Chicago, Illinois 60611; University of North Carolina School of Medicine (D.R.C.), Chapel Hill, North Carolina 27599; National Institute of Diabetes, Digestive and Kidney Disease (S.M.), National Institutes of Health, Bethesda, Maryland 20892; University of Washington, Veterans Affairs Puget Sound Health Care System (G.R.M.), Seattle and Tacoma, Washington 98493; Christie Hospital (S.M.S.), Manchester M20 4BX, United Kingdom; and University of Virginia Health Science Center (M.L.V.), Charlottesville, Virginia 22908

352 citations

Journal ArticleDOI
TL;DR: The KEEPS-Cog findings suggest that for recently postmenopausal women, MHT did not alter cognition as hypothesized, and women treated with o-CEE showed improvements in depression and anxiety symptoms over the 48 mo period, compared to women on placebo.
Abstract: Background Menopausal hormone therapy (MHT) reportedly increases the risk of cognitive decline in women over age 65 y. It is unknown whether similar risks exist for recently postmenopausal women, and whether MHT affects mood in younger women. The ancillary Cognitive and Affective Study (KEEPS-Cog) of the Kronos Early Estrogen Prevention Study (KEEPS) examined the effects of up to 4 y of MHT on cognition and mood in recently postmenopausal women. Methods and Findings KEEPS, a randomized, double-blinded, placebo-controlled clinical trial, was conducted at nine US academic centers. Of the 727 women enrolled in KEEPS, 693 (95.3%) participated in the ancillary KEEPS-Cog, with 220 women randomized to receive 4 y of 0.45 mg/d oral conjugated equine estrogens (o-CEE) plus 200 mg/d micronized progesterone (m-P) for the first 12 d of each month, 211 women randomized to receive 50 μg/d transdermal estradiol (t-E2) plus 200 mg/d m-P for the first 12 d of each month, and 262 women randomized to receive placebo pills and patches. Primary outcomes included the Modified Mini-Mental State examination; four cognitive factors: verbal learning/memory, auditory attention/working memory, visual attention/executive function, and speeded language/mental flexibility; and a mood measure, the Profile of Mood States (POMS). MHT effects were analyzed using linear mixed-effects (LME) models, which make full use of all available data from each participant, including those with missing data. Data from those with and without full data were compared to assess for potential biases resulting from missing observations. For statistically significant results, we calculated effect sizes (ESs) to evaluate the magnitude of changes. On average, participants were 52.6 y old, and 1.4 y past their last menstrual period. By month 48, 169 (24.4%) and 158 (22.8%) of the 693 women who consented for ancillary KEEPS-Cog were lost to follow-up for cognitive assessment (3MS and cognitive factors) and mood evaluations (POMS), respectively. However, because LME models make full use all available data, including data from women with missing data, 95.5% of participants were included in the final analysis (n = 662 in cognitive analyses, and n = 661 in mood analyses). To be included in analyses, women must have provided baseline data, and data from at least one post-baseline visit. The mean length of follow-up was 2.85 y (standard deviation [SD] = 0.49) for cognitive outcomes and 2.76 (SD = 0.57) for mood outcomes. No treatment-related benefits were found on cognitive outcomes. For mood, model estimates indicated that women treated with o-CEE showed improvements in depression and anxiety symptoms over the 48 mo of treatment, compared to women on placebo. The model estimate for the depression subscale was −5.36 × 10−2 (95% CI, −8.27 × 10−2 to −2.44 × 10−2; ES = 0.49, p < 0.001) and for the anxiety subscale was −3.01 × 10−2 (95% CI, −5.09 × 10−2 to −9.34 × 10−3; ES = 0.26, p < 0.001). Mood outcomes for women randomized to t-E2 were similar to those for women on placebo. Importantly, the KEEPS-Cog results cannot be extrapolated to treatment longer than 4 y. Conclusions The KEEPS-Cog findings suggest that for recently postmenopausal women, MHT did not alter cognition as hypothesized. However, beneficial mood effects with small to medium ESs were noted with 4 y of o-CEE, but not with 4 y of t-E2. The generalizability of these findings is limited to recently postmenopausal women with low cardiovascular risk profiles. Trial Registration ClinicalTrials.gov NCT00154180 and NCT00623311

326 citations


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Journal ArticleDOI
01 Feb 2011-Stroke
TL;DR: Evidence-based recommendations are included for the control of risk factors, interventional approaches to atherosclerotic disease of the cervicocephalic circulation, and antithrombotic treatments for preventing thrombosis and thromboembolic stroke.
Abstract: The aim of this updated statement is to provide comprehensive and timely evidence-based recommendations on the prevention of stroke among individuals who have not previously experienced a stroke or transient ischemic attack. Evidence-based recommendations are included for the control of risk factors, interventional approaches to atherosclerotic disease of the cervicocephalic circulation, and antithrombotic treatments for preventing thrombotic and thromboembolic stroke. Further recommendations are provided for genetic and pharmacogenetic testing and for the prevention of stroke in a variety of other specific circumstances, including sickle cell disease and patent foramen ovale.

2,299 citations

Journal ArticleDOI
TL;DR: Puberty is initiated when gonadotropin-releasing hormone begins to be secreted by the hypothalamus, and complementary genetic approaches in humans and mice identified genetic factors that determine the onset of puberty.
Abstract: Background Puberty, a complex biologic process involving sexual development, accelerated linear growth, and adrenal maturation, is initiated when gonadotropin-releasing hormone begins to be secreted by the hypothalamus. We conducted studies in humans and mice to identify the genetic factors that determine the onset of puberty. Methods We used complementary genetic approaches in humans and in mice. A consanguineous family with members who lacked pubertal development (idiopathic hypogonadotropic hypogonadism) was examined for mutations in a candidate gene, GPR54, which encodes a G protein–coupled receptor. Functional differences between wild-type and mutant GPR54 were examined in vitro. In parallel, a Gpr54-deficient mouse model was created and phenotyped. Responsiveness to exogenous gonadotropin-releasing hormone was assessed in both the humans and the mice. Results Affected patients in the index pedigree were homozygous for an L148S mutation in GPR54, and an unrelated proband with idiopathic hypogonadotro...

2,253 citations

Journal ArticleDOI
12 Jul 2001-Headache
TL;DR: The prevalence, sociodemographic profile, and the burden of migraine in the United States in 1999 and to compare results with the original American Migraine Study, a 1989 population‐based study employing identical methods are described.
Abstract: Objective.—To describe the prevalence, sociodemographic profile, and the burden of migraine in the United States in 1999 and to compare results with the original American Migraine Study, a 1989 population-based study employing identical methods. Methods.—A validated, self-administered questionnaire was mailed to a sample of 20 000 households in the United States. Each household member with severe headache was asked to respond to questions about symptoms, frequency, and severity of headaches and about headache-related disability. Diagnostic criteria for migraine were based on those of the International Headache Society. This report is restricted to individuals 12 years and older. Results.—Of the 43 527 age-eligible individuals, 29 727 responded to the questionnaire for a 68.3% response rate. The prevalence of migraine was 18.2% among females and 6.5% among males. Approximately 23% of households contained at least one member suffering from migraine. Migraine prevalence was higher in whites than in blacks and was inversely related to household income. Prevalence increased from aged 12 years to about aged 40 years and declined thereafter in both sexes. Fifty-three percent of respondents reported that their severe headaches caused substantial impairment in activities or required bed rest. Approximately 31% missed at least 1 day of work or school in the previous 3 months because of migraine; 51% reported that work or school productivity was reduced by at least 50%. Conclusions.—Two methodologically identical national surveys in the United States conducted 10 years apart show that the prevalence and distribution of migraine have remained stable over the last decade. Migraine-associated disability remains substantial and pervasive. The number of migraineurs has increased from 23.6 million in 1989 to 27.9 million in 1999 commensurate with the growth of the population. Migraine is an important target for public health interventions because it is highly prevalent and disabling.

2,012 citations

Journal ArticleDOI
01 Jan 1992-JAMA
TL;DR: The magnitude and distribution of the public health problem posed by migraine in the United States is described by examining migraine prevalence, attack frequency, and attack-related disability by gender, age, race, household income, geographic region, and urban vs rural residence.
Abstract: Objective. —To describe the magnitude and distribution of the public health problem posed by migraine in the United States by examining migraine prevalence, attack frequency, and attack-related disability by gender, age, race, household income, geographic region, and urban vs rural residence. Design. —In 1989, a self-administered questionnaire was sent to a sample of 15000 households. A designated member of each household initially responded to the questionnaire. Each household member with severe headache was asked to respond to detailed questions about symptoms, frequency, and severity of headaches. Setting. —A sample of households selected from a panel to be representative of the US population in terms of age, gender, household size, and geographic area. Participants. —After a single mailing, 20468 subjects (63.4% response rate) between 12 and 80 years of age responded to the survey. Respondents and non-respondents did not differ by gender, household income, region of the country, or urban vs rural status. Whites and the elderly were more likely to respond. Migraine headache cases were identified on the basis of reported symptoms using established diagnostic criteria. Results. —17.6% of females and 5.7% of males were found to have one or more migraine headaches per year. The prevalence of migraine varied considerably by age and was highest in both men and women between the ages of 35 to 45 years. Migraine prevalence was strongly associated with household income; prevalence in the lowest income group ( Conclusions. —A projection to the US population suggests that 8.7 million females and 2.6 million males suffer from migraine headache with moderate to severe disability. Of these, 3.4 million females and 1.1 million males experience one or more attacks per month. Females between ages 30 to 49 years from lower-income households are at especially high risk of having migraines and are more likely than other groups to use emergency care services for their acute condition. (JAMA. 1992;267:64-69)

1,576 citations

Journal ArticleDOI
04 Apr 2007-JAMA
TL;DR: Whether the effects of hormone therapy on risk of cardiovascular disease vary by age or years since menopause began is explored to explore and women who initiated hormone therapy closer toMenopause tended to have reduced CHD risk compared with the increase inCHD risk among women more distant from menopausal symptoms.
Abstract: ContextThe timing of initiation of hormone therapy may influence its effect on cardiovascular disease.ObjectiveTo explore whether the effects of hormone therapy on risk of cardiovascular disease vary by age or years since menopause began.Design, Setting, and ParticipantsSecondary analysis of the Women's Health Initiative (WHI) randomized controlled trials of hormone therapy in which 10 739 postmenopausal women who had undergone a hysterectomy were randomized to conjugated equine estrogens (CEE) or placebo and 16 608 postmenopausal women who had not had a hysterectomy were randomized to CEE plus medroxyprogesterone acetate (CEE + MPA) or placebo. Women aged 50 to 79 years were recruited to the study from 40 US clinical centers between September 1993 and October 1998.Main Outcome MeasuresStatistical test for trend of the effect of hormone therapy on coronary heart disease (CHD) and stroke across categories of age and years since menopause in the combined trials.ResultsIn the combined trials, there were 396 cases of CHD and 327 cases of stroke in the hormone therapy group vs 379 cases of CHD and 239 cases of stroke in the placebo group. For women with less than 10 years since menopause began, the hazard ratio (HR) for CHD was 0.76 (95% confidence interval [CI], 0.50-1.16); 10 to 19 years, 1.10 (95% CI, 0.84-1.45); and 20 or more years, 1.28 (95% CI, 1.03-1.58) (P for trend = .02). The estimated absolute excess risk for CHD for women within 10 years of menopause was −6 per 10 000 person-years; for women 10 to 19 years since menopause began, 4 per 10 000 person-years; and for women 20 or more years from menopause onset, 17 per 10 000 person-years. For the age group of 50 to 59 years, the HR for CHD was 0.93 (95% CI, 0.65-1.33) and the absolute excess risk was −2 per 10 000 person-years; 60 to 69 years, 0.98 (95% CI, 0.79-1.21) and −1 per 10 000 person-years; and 70 to 79 years, 1.26 (95% CI, 1.00-1.59) and 19 per 10 000 person-years (P for trend = .16). Hormone therapy increased the risk of stroke (HR, 1.32; 95% CI, 1.12-1.56). Risk did not vary significantly by age or time since menopause. There was a nonsignificant tendency for the effects of hormone therapy on total mortality to be more favorable in younger than older women (HR of 0.70 for 50-59 years; 1.05 for 60-69 years, and 1.14 for 70-79 years; P for trend = .06).ConclusionsWomen who initiated hormone therapy closer to menopause tended to have reduced CHD risk compared with the increase in CHD risk among women more distant from menopause, but this trend test did not meet our criterion for statistical significance. A similar nonsignificant trend was observed for total mortality but the risk of stroke was elevated regardless of years since menopause. These data should be considered in regard to the short-term treatment of menopausal symptoms.Trial Registrationclinicaltrials.gov Identifier: NCT00000611

1,571 citations