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The "pain rate" (episodes per year) is a measure of clinical severity and correlates with early death in patients with sickle cell anemia over the age of 20. Even when the fetal hemoglobin level is low, one can predict that small increments in the level may have an ameliorating effect on the pain rate and may ultimately improve survival. This outcome is particularly encouraging to investigators studying hydroxyurea and other treatments designed to increase the fetal hemoglobin level.

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Little is known about the descriptive epidemiology of androgen deficiency. In this study, we sought to address this issue by providing estimates of the crude and age-specific prevalence and incidence rates of androgen deficiency in a randomly sampled population-based cohort of middle-aged and older men. Data on androgen deficiency (defined using both signs/symptoms plus total and calculated free testosterone) were available for n = 1691 (baseline) and n = 1087 (follow-up) men from the Massachusetts Male Aging Study. Crude and age-specific prevalence and incidence rates were calculated. Based on these estimates, projections for the number of cases of androgen deficiency in the 40- to 69-yr-old U.S. male population were computed. Estimates of the crude prevalence of androgen deficiency at baseline and follow-up were 6.0 and 12.3%, respectively. Prevalence increased significantly with age. From baseline age-specific prevalence data, it is estimated that there are approximately 2.4 million 40- to 69-yr-old U.S. males with androgen deficiency. The crude incidence rate of androgen deficiency was 12.3 per 1,000 person-years, and the rate increased significantly (P < 0.0001) with age. Based on these incidence data, we can expect approximately 481,000 new cases of androgen deficiency per year in U.S. men 40-69 yr old.

Stroke is an important complication of sickle cell disease. Stroke prediction is clinically important because it offers the possibility of primary prevention. In 1992, transcranial Doppler (TCD) evidence of elevated intracranial internal carotid or middle cerebral artery velocity was demonstrated to be associated strongly with an increased risk of ischemic stroke. This study extends the original study and includes 125 more children, longer follow-up, and intracranial hemorrhage in the stroke-risk model. Elevated time averaged mean maximum blood flow velocity, especially when velocity is 200 cm/sec or greater by TCD, was associated strongly with stroke risk. The cases not predicted by TCD point to the need for more information on the optimal timing of TCD surveillance for stroke risk.

The acute chest syndrome (ACS), a pneumonia-like illness in sickle cell patients, is one of the most frequent causes of their morbidity and hospitalizations. Repeated ACS events may predict the development of chronic lung disease. ACS is reported as a frequent cause of death in these patients. We examine here the incidence and risk factors of ACS in 3,751 patients with sickle cell disease who were observed prospectively for at least 2 years (19,867 patient-years [pt-yrs]) as part of a multicenter national study group. The ACS, defined by a new pulmonary infiltrate on x-ray, occurred at least once in 1,085 patients (2,100 events). ACS incidence was higher in patients with homozygous sickle cell disease (SS; 12.8/100 pt-yrs) and in patients with sickle cell-beta(0) -thalassemic (9.4/100 pt-yrs), and lower in patients with hemoglobin (Hb) SC disease (5.2/100 pt-yrs) and patients with sickle cell-beta(+) thalassemia (3.9/100 pt-yrs). alpha-Thalassemia did not affect the rate of ACS incidence in SS patients. Within each Hb type the incidence was strongly but inversely related to age, being highest in children 2 to 4 years of age (25.3/100 pt-yrs in SS) and decreasing gradually to its lowest value in adults (8.8/100 pt-yrs in SS). In SS children (< 10 years of age), we documented an age-related within- person reduction in ACS attack rates. Adults with a higher ACS rate had a higher rate of mortality (from all causes) than those with low ACS rates. This increased rate of mortality might also have contributed to the decline in ACS rate with age. In multivariate analysis, other factors affecting incidence in SS patients were degree of anemia (lower ACS rates in patients with lower steady-state Hb levels) and fetal Hb (lower rates in patients with high fetal Hb). There was also a positive association between ACS rate and steady-state leukocyte count. The relationship of ACS rate to higher steady-state Hb levels in SS patients is unexplained but might be caused by increased blood viscosity.

This paper presents analyses from a comprehensive prospective cohort study of mid-aged women [the Massachusetts Women's Health Study (MWHS)], with numbers sufficient to provide stable estimates of parameters in the normal menopause transition. Three questions are addressed: what are the natural menopause transitions and when do they occur; what factors affect the transitions; and what signs and/or symptoms accompany the transitions? The data were obtained primarily from 5 years of follow-up of 2,570 women in Massachusetts who were aged 44-55 years as of January 1, 1982. Prospective study of the cohort consisted of six telephone contacts (T -T ) at 9 month intervals with excellent retention. A subset of the full cohort was defined that consisted of women who were premenopausal (rather than perimenopausal) at baseline (T ) (n = 1,178). Confirming prior reports, the age at natural menopause occurred at 51.3 years with a highly significant median difference (1.8 years) between current smokers and non-smokers. The new analyses reported here on median age at inception of perimenopause (47.5 years) and factors affecting it are consistent with findings for age at last menstrual period. Smokers tend to have not only an earlier but also shorter perimenopause. The length of the perimenopausal transition, estimated at about 3.5 years, has not been previously reported. The relationship between menopause transitions and symptom reporting appears to be transitory, with reporting rates showing an increase in the perimenopause and a compensatory decrease in postmenopause. The implications of combined hormone replacement therapy for future research on menopause in industrial societies is discussed in relation to these findings.

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