Mayo Clinic

About: Mayo Clinic is a healthcare organization based out in Rochester, Minnesota, United States. It is known for research contribution in the topics: Population & Cancer. The organization has 63387 authors who have published 169578 publications receiving 8114006 citations.

Relationship of serum sex steroid levels and bone turnover markers with bone mineral density in men and women: A key role for bioavailable estrogen

Abstract: Estrogen (E) deficiency associated with the menopause is the major cause of bone loss in aging women. However, men also lose significant amounts of bone with age, but they do not have the equivalent of menopause, and serum total testosterone (T) and E levels decline only marginally with age in men. Thus, it has been difficult to attribute bone loss in aging men to either T or E deficiency. Here, we show in a population-based, age-stratified sample of 346 men, aged 23-90 yr, that serum total T and E (estradiol plus estrone) levels decreased over the life span by 30% and 12%, respectively, but bioavailable (or nonsex hormone-binding globulin-bound) T and E levels decreased by 64% and 47%, respectively. In these men and in a parallel cohort of 304 women, aged 21-94 yr, serum PTH increased 84% and 64% over the life span, and urinary N-telopeptide of type I collagen (NTx) excretion, a bone resorption marker, increased 77% and 80% between age 50-85 yr in the men and women, respectively. By univariate analyses, serum bioavailable T and E levels correlated positively with bone mineral density (BMD) at the total body, spine, proximal femur, and distal radius and negatively with urinary NTx excretion in men and women. Urinary NTx excretion was also negatively associated with BMD in both sexes. By multivariate analyses, however, serum bioavailable E level was the consistent independent predictor of BMD in both men and postmenopausal women. Thus, bioavailable E levels decline significantly with age and are important predictors of BMD in men as well as women. These studies suggest that in contrast to traditional belief, age-related bone loss may be the result of E deficiency not just in postmenopausal women, but also in men.

Obstructive Sleep Apnea and the Recurrence of Atrial Fibrillation

Abstract: Background— We tested the hypothesis that patients with untreated obstructive sleep apnea (OSA) would be at increased risk for recurrence of atrial fibrillation (AF) after cardioversion. Methods and Results— We prospectively obtained data on history, echocardiogram, ECG, body mass index, hypertension, diabetes, NYHA functional class, ejection fraction, left atrial appendage velocity, and medications in patients with AF/atrial flutter referred for DC cardioversion. Forty-three individuals were identified as having OSA on the basis of a previous sleep study. Data regarding the use of continuous positive airway pressure (CPAP) and recurrence of AF were obtained for 39 of these patients. Follow-up data were also obtained in 79 randomly selected postcardioversion patients (controls) who did not have any previous sleep study. Twenty-seven of the 39 OSA patients either were not receiving any CPAP therapy (n=25) or were using CPAP inappropriately (n=2). Recurrence of AF at 12 months in these 27 patients was 82%, ...

Long-term outcome in patients undergoing surgical repair of tetralogy of Fallot.

Abstract: Background Although corrective surgery for tetralogy of Fallot has been available for more than 30 years, the occurrence of late sudden death in patients in whom surgery was apparently successful remains worrisome. Methods We studied long-term survival among 163 patients who survived 30 days after complete repair of tetralogy of Fallot, examining follow-up hospital records and death certificates when relevant. Results The overall 32-year actuarial survival rate among all patients who survived surgery was 86 percent, as compared with an expected rate of 96 percent in a control population matched for age and sex (P<0.01). Thirty-year actuarial survival rates were calculated for the patient subgroups. The survival rates among patients less than 5 years old, 5 to 7 years old, and 8 to 11 years old were 90, 93, and 91 percent, respectively -- slightly less than the expected rates (P<0.001, P = 0.06, and P = 0.02). Among patients 12 years old or older at the time of surgery, the survival rate was 76 percent, as...

The lifetime risk of suicide in schizophrenia: a reexamination.

Abstract: Background The psychiatry literature routinely quotes a lifetime schizophrenia suicide prevalence of 10% based on 1 meta-analysis and 2 studies of chronic schizophrenics. Objectives To build a methodology for extrapolating lifetime suicide prevalence estimates from published cohorts and to apply this approach to studies that meet inclusion criteria. Data sources We began with a MEDLINE search (1966-present) for articles that observed cohorts of schizophrenic patients. Exhaustive bibliography searching of each identified article brought the total number of articles reviewed to 632. Study selection Studies included in the meta-analysis observed a cohort of schizophrenic patients for at least 2 years, with at least 90% follow-up, and reported suicides. Articles are excluded for systematic age bias (ie, adolescents). Data extraction Extracted data included sample size, number of deaths, number of suicides, percentage of follow-up, and diagnostic system used. Data were extracted independently by 2 of us, and differences were resolved by consensus after re-review. Data synthesis Studies were divided into 2 groups: 32 studies of schizophrenics enrolled at various illness points (25 578 subjects) and 29 studies of schizophrenics identified at either illness onset or first admission (22 598 subjects). Regression models of the intersection of proportionate mortality (the percentage of the dead who died by suicide) and case fatality (the percentage of the total sample who died by suicide) were used to calculate suicide risk in each group. The estimate of lifetime suicide prevalence in those observed from first admission or illness onset was 5.6% (95% confidence interval, 3.7%-8.5%). Mixed samples showed a rate of 1.8% (95% confidence interval, 1.4%-2.3%). Case fatality rates showed no significant differences when studies of patients diagnosed with the use of newer systems were compared with studies of patients diagnosed under older criteria. Conclusion This study estimates that 4.9% of schizophrenics will commit suicide during their lifetimes, usually near illness onset.