Hemoglobin: normal values

Hematologists are not in agreement as to the "normal" amount of hemoglobin in the blood, nor is there agreement as to what amount of hemoglobin can be considered "a hemoglobin value of 100 per cent." Different hospitals base reports of hemoglobin on different standards, which obviously can be misleading. By biometric study of the great mass of data on hemoglobin content that has become available as a result of the blood procurement program, it should be possible to determine what "normal" values are and to provide a basis for uniformity in reporting.     

Centromere separation sequence in aged women and men

The centromere separation sequence of 5 old women (mean age 80.4 years), and 5 old men (mean age 75.5 years) was determined. Five young females (mean age 26.0 years) and 5 young males (mean age 27.4 years) served as controls. In each case 50 randomly selected lymphocyte mitoses were analysed microscopically and from photographs. In the groups of the young controls and aged men, the centromere separation sequence was clearly non-random and corresponded to the "normal sequence" observed in several earlier studies. In aged women chromosomes X, 8 and 10 divided earlier, while chromosomes 2, 3, 5 and 18 somewhat later than usual, but the individual and averaged patterns did not conspicuously differ from the "normal sequence". The premature centromere division (PCD) of X was not correlated with X-aneuploidy, and seemed not to correspond to the "long acentric fragment" often described in old females.     

Testicular and blood steroid levels in aged men

In this study, we have evaluated the hypophyso-gonadal axis in three groups of men aged 60-69, 70-79 and 80-91 years by measuring the intratesticular concentrations of several steroids (pregnenolone, progesterone, DHEA, DHEA-S, testosterone, estradiol) and serum levels of FSH, LH, testosterone, estradiol and sex hormone binding globulin (SHBG). The histological examination of testes revealed normal spermatogenesis in all examined samples. No significant changes in serum hormone and SHBG concentrations as well as in testicular steroid contents among the three groups of patients were found. However, the mean serum SHBG level was three times higher in the oldest men than in other groups and a positive correlation between patient's age and serum SHBG was observed. Therefore, the bioavailability of estradiol in the oldest men was likely diminished. Consequently, the hormonal status in aged men is rather unchanged but great variations observed between patients imply special cautious when the SHBG and estradiol levels are concerned.     

Risk factors for premature death in middle aged men

The causes of premature death and the associated risk factors were analysed in a cohort of 7935 middle aged men participating in a preventive population programme in Malmö. They were screened when aged 46-48 and then followed up for 3½-8 years. Two hundred and eighteen died, of whom 181 (83%) underwent necropsy. Three major causes of death were established: cancer in 61 (28%), deaths related to consumption of alcohol in 55 (25%), and coronary heart disease in 50 (23%).Distinctly different patterns of risk factors were found to be associated with each of the three main causes of premature death. In death due to coronary heart disease smoking (p=0·0062), serum cholesterol concentration (p=0·00014), serum triglyceride concentration (p=0·00013), systolic blood pressure (p=0·000012), and diastolic blood pressure (p=0·0021) were the strongest single determinants but diastolic blood pressure ceased to be a predictive factor in a multivariate analysis whereas all the other variables could be combined in a highly predictive logistic model. In death related to consumption of alcohol equal or even stronger associations were found for serum γ glutamyltransferase activity (p<0·0001), points scored in a questionnaire screening for alcoholism (p<0·0001), and, inversely, serum cholesterol (p=0·0046) and serum creatinine (p<0·0001) concentrations both when applied independently and when combined in a logistic model. In death due to cancer significant associations were found for serum urate concentration (p=0·023) and, inversely, serum cholesterol concentration (p=0·056-0·031).Malignant diseases and diseases related to consumption of alcohol were at least as prominent as cardiovascular disorders in causing premature death in the cohort of men studied. All three types of conditions are potentially avoidable and seem to be associated with significant and distinctive patterns of risk factors. These patterns should be used, as blood pressure and serum lipid concentrations already are, to predict the risk of premature death and indicate preventive measures.     

Hemoglobin values: comparative survey of the 1976 Canadian Olympic team.

In view of the role of hemoglobin in oxygen transport, the hemoglobin concentration in whole blood may indicate readiness for maximal physical performance. Hemoglobin concentrations were determined in members of the 1976 Canadian Olympic team and compared with those of the 1975 Canadian general population and with published data for the 1968 Australian and Dutch Olympic teams. The mean hemoglobin concentrations of the 123 male and 64 female Canadian Olympic athletes were 14.7 +/- 1.0 and 12.9 +/- 0.7 g/dL, respectively. Both male and female Canadian Olympic athletes had significantly lower (P less than 0.01) values than the other three groups. The suboptimal hemoglobin concentrations may be related to inadequate dietary intake of protein and iron.     

Risk factors for stroke in middle aged British men.

OBJECTIVE--To determine the risk factors for stroke in a cohort representative of middle aged British men. DESIGN--Prospective study of a cohort of men followed up for eight years. SETTING--General practices in 24 towns in England, Wales, and Scotland (the British regional heart study). SUBJECTS--7735 men aged 40-59 at screening, selected at random from one general practice in each town. MAIN OUTCOME MEASURE--Fatal and non-fatal strokes. RESULTS--110 of the men had at least one stroke; there were four times as many non-fatal as fatal strokes. The relative risk of stroke was 12.1 in men who had high blood pressure (systolic blood pressure greater than or equal to 160 mm Hg) and were current smokers compared with normotensive, non-smoking men. Diastolic blood pressure yielded no additional information, and former cigarette smokers had the same risk as men who had never smoked. Heavy alcohol intake was associated with a relative risk of stroke of 3.8 in men without previously diagnosed cardiovascular disease. Men with pre-existing ischaemic heart disease had an increased risk of stroke, but only when left ventricular hypertrophy on electrocardiography was also present. CONCLUSIONS--Systolic blood pressure, cigarette smoking, and left ventricular hypertrophy on electrocardiography in men with pre-existing ischaemic heart disease were found to be the major risk factors for stroke in middle aged British men. Heavy alcohol intake seemed to increase the risk of stroke in men without previously diagnosed cardiovascular disease. A large proportion of strokes should be preventable by controlling blood pressure and stopping smoking.     

Physical activity and stroke in British middle aged men.

OBJECTIVES--To assess the relation between physical activity and stroke and to determine the overall benefit of physical activity for all major cardiovascular events. DESIGN--Prospective study of a cohort of men followed up for 9.5 years. SETTING--General practices in 24 towns in England, Wales, and Scotland (British regional heart study). SUBJECTS--7735 men aged 40-59 at screening, selected at random from one general practice in each of 24 towns. MAIN OUTCOME MEASURES--Fatal and non-fatal strokes and heart attacks. RESULTS--128 major strokes (fatal and non-fatal) occurred. Physical activity was inversely associated with risk of stroke independent of coronary risk factors, heavy drinking, and pre-existing ischaemic heart disease or stroke (relative risk 1.0 for inactivity, 0.6 moderate activity, and 0.3 vigorous activity; test for trend p = 0.008). The association remained after excluding men reporting regular sporting (vigorous) activity. However, vigorous physical activity was associated with a marginally significant increased risk of heart attack compared with moderate or moderately vigorous activity in men with no pre-existing ischaemic heart disease or stroke (relative risk 1.6%; 95% confidence interval 0.96 to 2.8). In men with symptomatic ischaemic heart disease or stroke those doing moderately vigorous or vigorous activity had a risk of heart attack slightly higher than that in inactive men (relative risk = 1.6; 0.8 to 3.3). CONCLUSIONS--Moderate physical activity significantly reduces the risk of stroke and heart attacks in men both with and without pre-existing ischaemic heart disease. More vigorous activity did not confer any further protection. Moderate activity, such as frequent walking and recreational activity or weekly sporting activity, should be encouraged without restriction.     

TSH circadian secretions in aged men and effect of phosphatidylserine treatment

In 20 euthyroid aged men (from 65 to 85 years of age) no significant circadian periodicity of thyrotropin (TSH) secretion has been shown by the population mean cosinor method. At the end of a period of 30 days of hospitalization the cosinor evaluation of TSH secretion showed a restored highly significant (p less than 0.001) circadian rhythmicity in phosphatidylserine (PS) (400 mg/daily) treated group (10 aged subjects). By contrast, hospitalization seems to further deteriorate the periodicity of the hormone secretion in 10 placebo-treated subjects.     

Alcohol and ischaemic heart disease in middle aged British men.

The relation between alcohol intake and ischaemic heart disease was examined in a large scale prospective study of middle aged men drawn from general practices in 24 British towns. After an average follow up of 6.2 years 335 of the 7729 men had experienced a myocardial infarction (fatal or non-fatal) or sudden cardiac death. No significant relation was found between reported alcohol intake and the incidence of such events. Though the group of light daily drinkers had the lowest incidence of ischaemic heart disease events, it also contained the lowest proportion of current smokers, had the lowest mean blood pressure, had the lowest mean body mass index, and contained the lowest proportion of manual workers. These characteristics are more likely to account for the apparent protective effect of alcohol against ischaemic heart disease than a direct effect of alcohol. Compared with the effects of established risk factors alcohol seems to be quite unimportant in the development of ischaemic heart disease.     

Type A behaviour and ischaemic heart disease in middle aged British men.

The Bortner questionnaire, which measures aspects of type A (coronary prone) behaviour was completed by 5936 men aged 40-59 selected at random from one general practice in each of 19 British towns. The presence of ischaemic heart disease was determined at initial examination and the men were followed up for an average of 6.2 years for morbidity and mortality from myocardial infarction and for sudden cardiac death. Non-manual workers had significantly higher scores (more type A) than manual workers and the score decreased (less type A) with increasing age. After adjustment for social class and age men with higher scores had higher prevalences of ischaemic heart disease less marked for electrocardiographic evidence and more marked for response to a chest pain questionnaire (angina or possible myocardial infarction). A man''s recall of a doctor''s diagnosis of ischaemic heart disease, however, did not relate to his Bortner score. There was no significant relation between the Bortner score and the attack rate or incidence of major ischaemic heart disease events. In this study type A behaviour, as measured by the Bortner questionnaire, did not predict major ischaemic heart disease events in British middle aged men.     

Low systolic blood pressure and self perceived wellbeing in middle aged men.

OBJECTIVE--To examine the relation between systolic blood pressure and self perceived wellbeing in 50 year old men. DESIGN--Cross sectional population study of data derived from questionnaires and physical examination as a part of a cardiovascular risk factor survey. SETTING--City of Gothenburg, Sweden. STUDY POPULATION--776 men from a random population sample of 1016 men aged 50. METHODS--Self perceived wellbeing according to the Gothenburg quality of life questionnaire, which is an assessment of social, physical, and mental wellbeing in 15 different areas. MAIN RESULTS--Low systolic blood pressure was significantly (p < 0.05) related to impaired social wellbeing in four areas: work, home and family, financial situation, and housing. Of the items dealing with physical wellbeing, health, memory, and appetite were significantly related to blood pressure. As regards mental wellbeing, energy and self confidence were significantly related to systolic blood pressure. Diastolic blood pressure was significantly related to housing, memory, energy, patience, and self confidence. In multiple regression analyses that controlled for smoking, stress, physical activity, social activity, and emotional support, poor social, physical, and mental wellbeing were all significantly related to low systolic blood pressure independently of other factors. Low diastolic blood pressure was independently associated with poor physical and mental, but not social, wellbeing. CONCLUSION--Low systolic blood pressure was associated with poor perception of wellbeing in several areas. The cause is unclear.     

Lower skeletal muscle capillarization and VEGF expression in aged vs. young men.

Recently, we observed that muscle capillarization, vascular endothelial growth factor (VEGF) protein, and the VEGF mRNA response to acute exercise were lower in aged compared with young women (Croley AN, Zwetsloot KA, Westerkamp LM, Ryan NA, Pendergast aged men, Hickner RC, Pofahl WE, and Gavin TP. J Appl Physiol 99: 1875-1882, 2005). We hypothesized that similar age-related differences in muscle capillarization and VEGF expression would exist between young and aged men. Skeletal muscle biopsies were obtained from the vastus lateralis before and at 4 h after a submaximal exercise bout for the measurement of morphometry, capillarization, VEGF, KDR, and Flt-1 in seven aged (mean age 65 yr) and eight young (mean age 21 yr) sedentary men. In aged compared with young men, muscle capillary contacts and capillary-to-fiber perimeter exchange index were lower regardless of fiber type. Muscle VEGF mRNA and protein were lower in aged men both at rest and 4 h postexercise. Exercise increased muscle VEGF mRNA and protein and KDR mRNA independent of age group. There were no effects of exercise or age on muscle Flt-1 mRNA or protein or KDR protein. These results confirm that skeletal muscle capillarization and VEGF expression are lower in aged compared with young men.     

Cardiovascular effects of training for a marathon run in unfit middle aged men.

The effects of a 30 week exercise programme on serum lipid values, blood pressure, and cardiac function were assessed in a group of sedentary men aged 35-50 training for their first marathon. Mean serum cholesterol concentration (n = 33) fell by 12% from 6.54 (SE 0.18) to 5.76 (0.15) mmol/l (mean fall 0.78 mmol/l; 95% confidence interval 0.52 to 1.04 mmol/l), serum triglyceride concentration (n = 33) by 22% from 1.56 (0.17) to 1.21 (0.09) mmol/l (mean fall 0.34 mmol/l; 95% confidence interval 0.12 to 0.56 mmol/l), and mean blood pressure (n = 27) by 10% from 102 (2) to 92 (2) mm Hg (mean fall 10 mm Hg; 95% confidence interval 7 to 13 mm Hg). These changes were not explained by changes in body composition. Peak exercise left ventricular end diastolic volume (n = 16) increased with training; as a result of this and an increased exercise left ventricular ejection fraction peak exercise cardiac output increased from 19.9 (1.2) to 23.1 (3.0) l/min (mean rise 3.2 l/min; 95% confidence interval 1.5 to 5.0 l/min). Maximum oxygen consumption increased from 33.9 (1.6) to 39.0 (1.3) ml/kg/min (mean rise 5.0 ml/kg/min; 95% confidence interval 1.8 to 8.2 ml/kg/min). This study showed favourable effects on coronary risk factors and cardiac function and supports the place of regular exercise in coronary prevention programmes.