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Impotence and Its Medical and Psychosocial Correlates: Results of the Massachusetts Male Aging Study

Henry Feldman et al.Jan 1, 1994

Reproductive Medicine

General Health Professions

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Reproductive Medicine

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Age Trends in the Level of Serum Testosterone and Other Hormones in Middle-Aged Men: Longitudinal Results from the Massachusetts Male Aging Study

Henry Feldman et al.Feb 1, 2002

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We used longitudinal data from the Massachusetts Male Aging Study, a large population-based random-sample cohort of men aged 40-70 yr at baseline, to establish normative age trends for serum level of T and related hormones in middle-aged men and to test whether general health status affected the age trends. Of 1,709 men enrolled in 1987-1989, 1,156 were followed up 7-10 yr afterward. By repeated-measures statistical analysis, we estimated simultaneously the cross-sectional age trend of each hormone between subjects within the baseline data, the cross-sectional trend between subjects within the follow-up data, and the longitudinal trend within subjects between baseline and follow-up. Total T declined cross-sectionally at 0.8%/yr of age within the follow-up data, whereas both free and albumin-bound T declined at about 2%/yr, all significantly more steeply than within the baseline data. Sex hormone-binding globulin increased cross-sectionally at 1.6%/yr in the follow-up data, similarly to baseline. The longitudinal decline within subjects between baseline and follow-up was considerably steeper than the cross-sectional trend within measurement times for total T (1.6%/yr) and bioavailable T (2-3%/yr). Dehydroepiandrosterone, dehydroepiandrosterone sulfate, cortisol, and estrone showed significant longitudinal declines, whereas dihydrotestosterone, pituitary gonadotropins, and PRL rose longitudinally. Apparent good health, defined as absence of chronic illness, prescription medication, obesity, or excessive drinking, added 10-15% to the level of several androgens and attenuated the cross-sectional trends in T and LH but did not otherwise affect longitudinal or cross-sectional trends. The paradoxical finding that longitudinal age trends were steeper than cross-sectional trends suggests that incident poor health may accelerate the age-related decline in androgen levels.

Molecular Biology

Internal Medicine

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INCIDENCE OF ERECTILE DYSFUNCTION IN MEN 40 TO 69 YEARS OLD: LONGITUDINAL RESULTS FROM THE MASSACHUSETTS MALE AGING STUDY

Catherine Johannes et al.Feb 1, 2000

We estimated the incidence of erectile dysfunction in men 40 to 69 years old at study entry during an average 8.8-year followup, and determined how risk varied with age, socioeconomic status and medical conditions.Data from a randomly sampled population based longitudinal study of Massachusetts men were analyzed. A total of 1,709 men completed the baseline interview during 1987 to 1989 and 1,156 survivors completed followup from 1995 to 1997. The analysis sample consisted of 847 men without erectile dysfunction at baseline and with complete followup information. Erectile dysfunction was assessed by discriminant analysis of 13 questions from a self-administered sexual function questionnaire and a single global self-rating question.The crude incidence rate for erectile dysfunction was 25.9 cases per 1,000 man-years (95% confidence interval [CI] 22.5 to 29.9). The annual incidence rate increased with each decade of age and was 12.4 cases per 1,000 man-years (95% CI 9.0 to 16.9), 29.8 (24.0 to 37.0) and 46.4 (36.9 to 58.4) for men 40 to 49, 50 to 59 and 60 to 69 years old, respectively. The age adjusted risk of erectile dysfunction was higher for men with lower education, diabetes, heart disease and hypertension. Population projections for men 40 to 69 years old suggest that 17,781 new cases of erectile dysfunction in Massachusetts and 617,715 in the United States (white males only) are expected annually.Although prevalence estimates and cross-sectional correlates of erectile dysfunction have recently been established, incidence estimates were lacking. Incidence is necessary to assess risk, and plan treatment and prevention strategies. The risk of erectile dysfunction was about 26 cases per 1,000 men annually, and increased with age, lower education, diabetes, heart disease and hypertension.

Internal Medicine

Endocrinology

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Age, Disease, and Changing Sex Hormone Levels in Middle-Aged Men: Results of the Massachusetts Male Aging Study*

Anna Gray et al.Nov 1, 1991

To evaluate the hypothesis that endocrine profiles change with aging independently of specific disease states, we examined the age trends of 17 major sex hormones, metabolites, and related serum proteins in 2 large groups of adult males drawn from the Massachusetts Male Aging Study, a populationbased cross-sectional survey of men aged 39–70 yr conducted in 1986–89. Group 1 consisted of 415 men who were free of obesity, alcoholism, all prescription medication, prostate problems, and chronic illness (cancer, coronary heart disease, hypertension, diabetes, and ulcer). Group 2 consisted of 1294 men who reported 1 or more of the above conditions. Each age trend was satisfactorily described by a constant percent change per yr between ages 39–70 yr. Free testosterone declined by 1.2%/yr, and albumin-bound testosterone by 1.0%/yr. Sex hormone-binding globulin (SHBG), the major serum carrier of testosterone, increased by 1.2%/yr, with the net effect that total serum testosterone declined more slowly (0.4%/yr) than the free or albumin-bound pools alone. Among the major androgens and metabolites, androstane-3α,17β-diol (androstanediol; 0.8%/yr) and androstanediol glucuronide (0.6%/yr) declined less rapidly than free testosterone, while 5α-dihydrotestosterone remained essentially constant between ages 39–70 yr. Androstenedione declined at 1.3%/yr, a rate comparable to that of free testosterone, while the adrenal androgen dehydroepiandrosterone (3.1%/yr) and its sulfate (2.2%/yr) declined 2–3 times more rapidly. The levels of testosterone, SHBG, and several androgen metabolites followed a parallel course in groups 1 and 2, remaining consistently 10–15% lower in group 2 across the age range of the study. Subgroup analyses suggested that obese subjects might be responsible for much of the group difference in androgen level. Serum concentrations of estrogens and cortisol did not change significantly with age or differ between groups. Of the pituitary gonadotropins, FSH increased at 1.9%/yr, LH increased at 1.3%/yr, and PRL declined at 0.4%/yr, with no significant difference between groups 1 and 2. This study provides epidemiological evidence for some hormone age trends that were previously documented only in smaller, uncontrolled, or questionably representative samples. We found no significant difference between healthy men (group 1) and less healthy men (group 2) with respect to the percent rate of change of any of the serum hormone, metabolite, or protein concentrations measured. The 10–15% lower levels of testosterone, SHBG, and some androgen metabolites in the less healthy men, which were maintained between ages 39–70 yr, might be causes, effects, or mere correlates of disease.

Internal Medicine

Cell Biology

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Outcomes of a Field Trial to Improve Children's Dietary Patterns and Physical Activity

Russell Luepker et al.Mar 13, 1996

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Prevalence of Vitamin D Deficiency Among Healthy Adolescents

Catherine Gordon et al.Jun 1, 2004

Background

Although vitamin D deficiency has been documented as a frequent problem in studies of young adults, elderly persons, and children in other countries, there are limited data on the prevalence of this nutritional deficiency among healthy US teenagers.

Objective

To determine the prevalence of vitamin D deficiency in healthy adolescents presenting for primary care.

Design

A cross-sectional clinic-based sample.

Setting

An urban hospital in Boston.

Participants

Three hundred seven adolescents recruited at an annual physical examination to undergo a blood test and nutritional and activity assessments.

Main Outcome Measures

Serum levels of 25-hydroxyvitamin D (25OHD) and parathyroid hormone, anthropometric data, nutritional intake, and weekly physical activity and lifestyle variables that were potential risk factors for hypovitaminosis D.

Results

Seventy-four patients (24.1%) were vitamin D deficient (serum 25OHD level, ≤15 ng/mL [≤37.5 nmol/L]), of whom 14 (4.6%) were severely vitamin D deficient (25OHD level, ≤8 ng/mL [≤20 nmol/L]). By using a broader definition (25OHD level, ≤20 ng/mL [≤50 nmol/L]), 129 patients (42.0%) were vitamin D insufficient. Serum 25OHD levels were inversely correlated with parathyroid hormone levels (r= −0.29), and were 24% lower during winter compared with summer. In a final multivariate model, season, ethnicity, milk and juice consumption, body mass index, and physical activity were significant independent predictors of hypovitaminosis D.

Conclusions

Vitamin D deficiency was present in many US adolescents in this urban clinic-based sample. The prevalence was highest in African American teenagers and during winter, although the problem seems to be common across sex, season, and ethnicity.

Physiology

Internal Medicine

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Erectile Dysfunction and Coronary Risk Factors: Prospective Results from the Massachusetts Male Aging Study

Henry Feldman et al.Apr 1, 2000

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Background. Erectile dysfunction (ED), a wide spread and troublesome condition among middle-aged men, is partly vascular in origin. In the Massachusetts Male Aging Study, a random-sample cohort study, we investigated the relationship between baseline risk factors for coronary heart disease and subsequent ED, on the premise that subclinical arterial insufficiency might be manifested as ED. Methods. Men ages 40–70, selected from state census lists, were interviewed in 1987–1989 and reinterviewed in 1995–1997. Data were collected and blood was drawn in participants' homes. ED was assessed from responses to a privately self-administered questionnaire. Analysis was restricted to 513 men with no ED at baseline and no diabetes, heart disease, or related medications at either time. Results. Cigarette smoking at baseline almost doubled the likelihood of moderate or complete ED at followup (24% vs 14%, adjusted for age and covariates, P = 0.01). Cigar smoking and passive exposure to cigarette smoke also significantly predicted incident ED, as did overweight (body-mass index ≥ 28 kg/m2) and a composite coronary risk score. Weaker prospective associations were seen for hypertension and dietary intake of cholesterol and unsaturated fat. Conclusions. Erectile dysfunction and coronary heart disease share some behaviorally modifiable determinants in men who, like our sample, are free of manifest ED or predisposing illness. Open questions include whether modification of coronary risk factors can prevent ED and whether ED may serve as a sentinel event for coronary disease.

Internal Medicine

Endocrinology

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A Randomized Trial of Sugar-Sweetened Beverages and Adolescent Body Weight

Cara Ebbeling et al.Sep 21, 2012

Consumption of sugar-sweetened beverages may cause excessive weight gain. We aimed to assess the effect on weight gain of an intervention that included the provision of noncaloric beverages at home for overweight and obese adolescents.

Physiology

Internal Medicine

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Mathematical theory of complex ligand-binding systems at equilibrium: Some methods for parameter fitting

Henry FeldmanAug 1, 1972

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In this report, the equilibrium composition of a multicomponent crossreactive ligand-binding system is characterized by solving the mass action equations. Several results in simulation and parameter fitting for radioimmunoassay, ion-protein reactions, etc., are derived from these equations: (1) The Scatchard binding curve bound-to-free ratio for ligand (vs bound ligand concentration) is shown to be a hyperbola, and is expressed in the explicit form y = f(x), for the case of two ligands and one binding group, or one ligand and two binding groups. (2) Graphic methods are presented for estimation of binding parameters (affinity constants and total concentrations of reactant) by measuring the Scatchard curve in the abovementioned cases. (3) Computational methods are presented for fitting parameters to data in the case of arbitrarily many ligands and arbitrarily many binding groups. (4) Formulae are derived for the partial derivatives of the bound-to-free ligand ratio with respect to all binding parameters. (5) An illustrative application is made to data from the literature on thyroid hormone binding.

Biochemistry

Cell Biology

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Testosterone, sex hormone-binding globulin, and the development of type 2 diabetes in middle-aged men: prospective results from the Massachusetts male aging study.

Rebecca Stellato et al.Apr 1, 2000

OBJECTIVE: The objective was to examine prospectively the association between low testosterone and sex hormone-binding globulin (SHBG) levels and the subsequent development of type 2 diabetes in men. RESEARCH DESIGN AND METHODS: Analyses were conducted on the cohort of the Massachusetts Male Aging Study, a population-based random sample of men aged 40-70. Of the 1,709 men enrolled in 1987-1989 (T1), 1,156 were followed up 7-10 years later (T2). Testosterone and SHBG levels at T1 were used to predict new cases of diabetes between T1 and T2. RESULTS: After controlling for potential confounders, diabetes at follow-up was predicted jointly and independently by lower baseline levels of free testosterone and SHBG. The odds ratio for future diabetes was 1.58 for a decrease of 1SD in free testosterone (4 ng/dl) and 1.89 for a 1SD decrease in SHBG (16 nmol/l), both significant at P < 0.02. CONCLUSIONS: Our prospective findings are consistent with previous, mainly cross-sectional reports, suggesting that low levels of testosterone and SHBG play some role in the development of insulin resistance and subsequent type 2 diabetes.

Internal Medicine

Endocrinology

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Paper

Internal Medicine

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Impotence and Its Medical and Psychosocial Correlates: Results of the Massachusetts Male Aging Study

Age Trends in the Level of Serum Testosterone and Other Hormones in Middle-Aged Men: Longitudinal Results from the Massachusetts Male Aging Study

INCIDENCE OF ERECTILE DYSFUNCTION IN MEN 40 TO 69 YEARS OLD: LONGITUDINAL RESULTS FROM THE MASSACHUSETTS MALE AGING STUDY

Age, Disease, and Changing Sex Hormone Levels in Middle-Aged Men: Results of the Massachusetts Male Aging Study*

Outcomes of a Field Trial to Improve Children's Dietary Patterns and Physical Activity

Objective.

Design.

Participants.

Intervention.

Main Outcome Measures.

Results.

Conclusion.

Prevalence of Vitamin D Deficiency Among Healthy Adolescents

Background

Objective

Design

Setting

Participants

Main Outcome Measures

Results

Conclusions

Erectile Dysfunction and Coronary Risk Factors: Prospective Results from the Massachusetts Male Aging Study

A Randomized Trial of Sugar-Sweetened Beverages and Adolescent Body Weight

Mathematical theory of complex ligand-binding systems at equilibrium: Some methods for parameter fitting

Testosterone, sex hormone-binding globulin, and the development of type 2 diabetes in middle-aged men: prospective results from the Massachusetts male aging study.