A review of epidemiologic studies of vasectomy

A number of epidemiologic studies of vasectomy have been published in recent years. These studies have been methodologically diverse and have involved several groups of investigators in several countries. The studies are consistent in finding no long-term effects of vasectomy on the risk of cardiovascular disease, cancer, impotence, prostatic disease, or disease related to immune function and dysfunction. Continued follow-up of vasectomized men to evaluate further the possibility of adverse effects of vasectomy is recommended. At this time, epidemiologic studies of vasectomy in man are strongly reassuring. Vasectomy decreases prostatic secretory function. In a study conducted by Sidney, no association was found between vasectomy and benign prostatic hypertrophy or prostatic cancer. Massey et al. found that the incidence of impotence was 1.9/1000 man-years of observation in men with vasectomy and 1.7/1000 man-years in non-vasectomized men, a difference that was not statistically significant. 3 studies examining the risk of malignant and nonmalignant neoplasms in vasectomized and nonvasectomized men revealed that vasectomy was not associated with an increased risk of malignant or nonmalignant neoplasms.     

Incidence of disease after vasectomy: a record linkage retrospective cohort study.

OBJECTIVE--To determine whether vasectomy is associated with an increased risk of several diseases, and in particular testicular cancer, after operation. DESIGN--Retrospective cohort study using linked medical record abstracts. SETTING--Six health districts in Oxford region. SUBJECTS--13,246 men aged 25-49 years who had undergone vasectomy between 1970 and 1986, and 22,196 comparison subjects who had been admitted during the same period for one of three specified elective operations, appendicitis, or injuries. MAIN OUTCOME MEASURES--Hospital admission and death after vasectomy or comparison event. RESULTS--The mean durations of follow up were 6.6 years for men with a vasectomy and 7.5 years for men with a comparison condition. The relative risk of cancer of the testis in the vasectomy cohort (4 cases) compared with that in the other cohorts (17 cases) was 0.46 (95% confidence interval 0.1 to 1.4), that of cancer of the prostate (1 v 5 cases) 0.44 (0.1 to 4.0), and that of myocardial infarction (97 v 226 cases) 1.00 (0.8 to 1.3). There was no evidence of an increase associated with vasectomy in the incidence of a range of other diseases. CONCLUSIONS--Vasectomy was not associated with an increased risk of testicular cancer or the other diseases studied. With respect to prostatic cancer, while we found no cause for concern, longer periods of observation on large numbers of men are required.     

Possible mechanisms of vasectomy-exacerbated atherosclerosis

Our laboratory as well as those of others have demonstrated that in experimental animals vasectomy results in immune-complex deposition not only in the reproductive tract but also in the renal glomerulus. We have shown that in two species of monkeys vasectomy results in a significant increase in atherosclerosis and have postulated that this may be due to circulating immune complexes. We have shown a mild change in arteriolar vessels in a small study of vasectomized men and have found a mild but insignificant increase in systolic blood pressure in vasectomized men over time compared to an age-matched group. One cannot ignore the fact that persistent autoimmune responses to spermatozoal antigens are generated in both vasectomized men and animals. The paucity of direct information about whether vasectomy exacerbates atherosclerosis in human subjects has made reliance on animal studies unavoidable. But to date there is no evidence that vasectomy causes a similar effect in human beings.     

Current status of the endocrinological effects of vasectomy

The relevant literature which has appeared, primarily within the last several years, in regard to the endoncrinological effects of vasectomy is reviewed. Focus is on early animal studies, examinations of interstitial tissue, short-term endocrine studies in animals and man, and long-term endocrine studies in man. Suspicion that vasectomy may influence androgen and gonadotropin status has reappeared recently because of experimental investigations of vasectomized rats and human vasectomy follow-up studies. The possibility that vasectomy is accompanied by untoward consequences to the endocrine system, which might become manifest shortly after the procedure or later in life, received support from recent animal investigations. During the 1972-1975 period, several reports appeared which attempted to clarify what effect vasectomy had upon the human pituitary-gonadal axis. Recently, there have been several prospective long-term studies on the pituitary-testicular axis in vasectomized men. Several areas where additional research is necessary are identified.     

Prevalencia de obesidad y riesgo cardiovascular asociado en la población general de un área de salud de Extremadura. Estudio Hermex

Introduction and objectivesTo estimate the prevalence of obesity and its associated cardiovascular risk in the general population of a health area in Extremadura.Materials and methodsA cross-sectional study on a random population sample aged 25-79 years from the Don Benito-Villanueva (Badajoz) health area. Risk factors and cardiovascular disease were examined. Anthropometric and blood pressure measurements were collected, and a blood sample was taken. Obese subjects were categorized into different risk levels as proposed by the Spanish Society for the Study of Obesity, and the influence of obesity on estimation of the risk of ischemic heart disease was studied using the Framingham function, as adapted for Spain.ResultsA total of 2833 of the 3521 subjects screened (80.5%) participated in the study. Mean age was 51.2 years (SD 14.7), and 46.5% were males. Male subjects had a greater prevalence of overweight and obesity (46.2% and 37.7% respectively) as compared to females (37.7% and 32.6%) (p<0.005 and p<0.05 respectively). Only 10% of obese subjects had no increased cardiovascular risk. Obesity was associated to an 8-fold increase in the presence of a high risk for ischemic heart disease in females (p<0.001), as compared to a 1.4-fold increase in males (p=0.095).ConclusionsObesity is highly prevalent and affects, together with overweight, 74.1% of the population in an Extremadura health area. A vast majority of obese subjects have an increased cardiovascular risk, which is very marked for ischemic heart disease in females.     

Primates: Their use in research on vasectomy

Studies based on experimental vasectomies clearly reveal marked species differences in response to vasectomy. In rats, vasectomy invariably results in granuloma formation at the surgical site. In rabbits, immune-complex orchitis develops. Allergic orchitis may also develop in guinea pigs, and the morphological lesions can be adoptively transferred. My co-workers and I have been able to study systematically, biochemically, hormonally, pathologically, and immunologically, primates vasectomized up to 14 years earlier and to compare them with age-matched controls. We have monitored antibody levels in vasectomized rhesus and cynomolgus macaques by sperm-agglutination, sperm-immobilization, and indirect immunofluorescence techniques. Antibodies develop in almost every monkey, in some as early as 10 days after vasectomy. About 50% retain such circulating antisperm antibodies. In men, antibody development is less rapid, and about half of vasectomized men reveal detectable levels. Testicular histopathological studies have revealed detectable levels. Testicular histopathological studies have revealed orchitis, aspermatogenesis, or both, resembling allergic orchitis in most of the vasectomized monkeys and in about one-fourth of the controls. Limited studies of human material reveal some testicular changes. Epididymitis and epididymal granuloma occur exclusively in the vasectomized animals. Use of immunofluorescence has revealed significantly more granular deposits of IgA, IgG, and/or C3 in the basal lamina of the ductus efferens and the caput epididymidis of the vasectomized monkeys. Similar studies on human material have not been done. Both cynomolgus and rhesus macaques have proved to be excellent models for research in atherosclerosis and so have been used to determine whether constant sperm antigen leakage causes immune-complex formation that might result in arteritis and atherosclerosis. Evaluation of the cardiovascular systems from such animals has revealed that vasectomized monkeys have more frequent, more extensive, and more severe arteriosclerosis than age-matched controls. Epidemiological studies are currently under way to determine whether such an effect also occurs in men after vasectomy.     

Y a-t-il encore une place pour la chirurgie dans le traitement de l'infertilité masculine?

Considerable progress has been recently made in the biological treatement of male infertility. In parallel surgical techniques improved with the main impact of microsurgery. Varicoceles represent the pathology where surgery has the more questionable place. In fact it usualy increases the quality of the sperm, but has no impact on the pregnancy rate. Surgery is unquestionable for cryptorchidism after a failure of the hormonal treatment. Surgical treatment for excretory azoospermia is based on microsurgery performed by a well trained team. The results are better when the obstruction has a congenital origin, and a year is requiered for the clinical evaluation. Microsurgery allows to obtain a 50% prenancy rate after vasovasostomy performed after a vasectomy. But a sperm banking must be systematically done before vasectomy, due to the deterioration of the quality of the restults with time. The ejaculatory duct obstruction may lead to endoscopic procedures. Finally epididymal or vas sperm collection has allow to obtain some pregnancies. But the success of ICSI from surgical epididymal or deferential fluid calls for a completely new approach to the range of indications and surgical protocols. The indications must be clearly defined, the need for a genetic screening is mandatory. And the quality of the obtained pregnancies remains the main question for the next years.     

Inflammatory changes in the epididymis after vasectomy in the Lewis rat

The epididymides of Lewis rats were studied at intervals up to 7 months after vasectomy, vasectomy followed 3 months later by vasovasostomy, or sham operations. Epididymal histology was related to testicular alterations and to serum antisperm antibodies as determined with an enzyme-linked immunosorbent assay. In vasectomy and vasovasostomy groups. 13 of 33 rats had testicular alterations, which consisted mainly of pronounced depletion of germ cells. Over half of the rats with testicular alterations also had severe epididymal lesions that included interstitial changes characteristic of an inflammatory response. These consisted of aggregates of mononuclear cells, including lymphocytes, plasma cells, and macrophages. The lumina of epididymides with interstitial changes contained polymorphonuclear leukocytes and/or macrophages. All animals with altered testes had greatly decreased numbers of epididymal sperm. In many instances, the lumen of the proximal cauda epididymidis was collapsed, and columnar cells of the epididymal epithelium contained many very large lysosomes. The distal cauda epididymidis was distended with sperm and debris. None of the rats that lacked testicular alterations showed epididymal changes. Mean serum antisperm antibody levels were significantly higher for rats with epididymal interstitial changes than for animals without such epididymal alterations. Infiltrations of inflammatory cells into the epididymal interstitium and lumen are part of the constellation of changes that occurs after immunization with testicular homogenates to produce experimental allergic orchitis. The observations reported here support the hypothesis that reproductive tract alterations after vasectomy in this model have an immune basis.     

Role de la glande pineale dans la regulation de l’axe hypothalamo-hypophyso-testiculaire

The role of the pineal gland and of its main hormone, melatonin, has not yet been clearly defined. The best known activity of the gland is antigonadal, at least in the experimental animals. In fact, the administration of melatonin or the modification of the light/darkness ratio, that is considered the most important regulatory mechanism of the melatonin-synthetic activity, leads to a gonadal regression by which all the morphological and hormonal parameters are modified. Such a mechanism is not operating in humans. However, data exist indicating a role for the pineal in this species. Our experimental data and those of the litterature indicate that the action of melatonin seems to be principally at the hypothalamic level, even though a direct action at the pituitary and gonadal levels cannot be excluded     

Reperméabilisation microchirurgicale après vasectomie. Résultats et facteurs de réussite

Microsurgical vasectomy reversal is a challenge for the physician but successful treatment depends on the experience and skills of the surgeon. Fertility can often be restored, thus avoiding the need for artificial reproductive techniques. Also, the surgical procedures can be combined with sperm aspiration and cryopreservation, to be used for Intracytoplasmic sperm injection (ICSI) in cases of surgical failure. We describe the results of 217 vasovasostomy procedures, with special emphasis on recent technical refinements and prognostic indicators. Between 1998 and 2002 we performed 217 vasovasostomy-procedures in an outpatient clinic setting. Refertilisation was successful in 76.5%, spontaneous pregnancy occurred in 42% of the couples after a follow-up of at least 1 year. The main prognostic factors determining the outcome of the surgery was the interval between vasectomy and refertilisation and the age of the female partner: patency was 89% after an interval of less than 5 years and pregnancy occurred in 56% of these couples. After an interval of more than 10 years patency decreased to 75% and pregnancy results dropped to 24%. Epididymal dysfunction with poor motility score and secondary epididymal obstruction appeared to be common after a long interval. Furthermore, in men with partners older than 35 years of age pregnancy was only 21%, indicating limited ovarian reserve as an important factor in determining the final outcome. In men with a long obstructive interval between vasectomy and reversal an obstruction of the epididymis can be found due to a blow-out of the epididymal tubule with subsequent leakage of semen in the organ and fibrosis. A vaso-epididymostomy procedure is needed to treat the obstruction. Recently, surgical refinements, such as the invagination technique, have been introduced for the vaso-epididymostomy procedure, showing promising first results. This simplified technique enables less experienced microsurgeons to perform this difficult operation successfully. The results of vasectomy reversal procedures can be improved substantially if the surgeon is able to perform a vaso-epididymostomy in cases of a secondary epididymal obstruction, occurring in about 25% of men with an interval of more than 10 years.     

Efectividad de la vacuna antigripal en la prevención de la gripe en personas mayores de 65 años

IntroductionInfluenza is one of the diseases with the greatest epidemiological impact and of maximum relevance in the management of health services. The flu vaccine can have great variability each season, so our objective was to find out the effectiveness of the flu vaccine for the 2017/2018 season for the prevention of severe cases of flu in people over 65 years of age in a 385-bed acute general hospital.Material and methodStudy of cases and controls. All hospitalized patients with laboratory-confirmed influenza older than 65 years during the 2017/2018 season were included. Those who met the criteria for a severe case of influenza were considered cases. Those who did not meet the severity criteria were considered controls. Factors associated with the development of severe influenza were calculated.ResultsThe median age was 68 years (SD 91.87). The attack rate was 0.23 per hundred inhabitants and the vaccine effectiveness was 38%. The vaccinated and unvaccinated groups were different in terms of age (p < 0.0481). Vaccination status against severe influenza was found to be an independent protective factor (OR = 0.840; 0.746-0.913).ConclusionsThe effectiveness of influenza vaccination provided greater protection against infection and reduced the severity of influenza in older hospitalized patients. These findings should be taken into account to improve vaccination strategies and achieve better vaccination coverage in the population at risk.     

Espasticidad tras ictus: ¿la edad es un factor de riesgo? Estudio observacional de la espasticidad en pacientes neurovasculares en una serie retrospectiva de dos centros

ObjectiveApproximately one third of patients who have suffered a stroke develop spasticity. Since clinical observations that spasticity in the elderly population is lower after stroke, and disagreement about risk factors between different authors, an analysis is performed on the variables that influence the development of spasticity.The objective of the study is to determine the how many factors influence spasticity outcome, and the prevalence of spasticity in patients who have suffered a stroke and require intensive rehabilitation treatment.MethodA retrospective assessment was carried out on a total of 554 patients from two neurorehabilitation centres. A record was made of sociodemographic data, aetiology, type and location of stroke, motor and sensory deficits, language and swallowing impairment, incontinence, cognitive and mood state. Spasticity levels at admission and at the third month were studied in 462 patients using the Ashworth scale. Multivariate regression analyses were used to assess the risk factors for spasticity present at the third month after stroke.ResultsThe mean age of the patients was 67.3 years, of which 67.1% were men, and with ischemic aetiology in 76.5%. On admission 31.4% of patients had spasticity, and this increased to 54.8% at the 3^rd month. The absolute risk factor for spasticity was motor index (OR 1.04; 95% CI 1.03-1.05). When this factor was omitted, the variables with predictive ability were: age less than 75 years (OR 0.52; 95% CI 0.30-0.90), sensory impairment (OR 0.66; 95% CI 0.37-1.20), and lower Barthel index score (OR 1.02; 95% CI 1.01-1.03). There was no significant relationship for gender, physiopathological mechanism (ischaemic/haemorrhagic), stroke location, aphasia, or cognitive impairment.ConclusionThe prevalence of spasticity in stroke at third month of follow-up was 54.8%. Motor index is the independent predictor of spasticity. Patients younger than 75 years old, with sensory impairment and low Barthel index score are more likely to develop spasticity.     

Mr. de la Roche replies

Review of the literature reveals sporadic but true increases in the prevalence and death rates for asthma over the past 25 years. Although changes in hereditary, allergic and environmental factors must be considered as possible causes of this increase, its suddenness points to risk factors that change rapidly. Such is the case with atmospheric pollutants, notably nitrogen dioxide and particles, both of which have been shown to have adverse effects on the tracheobronchial tree. These pollutants tend to concentrate inside homes, especially since the early 1980s, when the energy crisis brought about changes in the home environment.     

Cigarettes pendant la grossesse,poids de naissance et mortalité périnatale

This study is based on a 10% random sample of medical certifications of birth in Quebec in 1970-71 and on additional information obtained from perinatal death certificates and birth registrations. Smoking in pregnancy significantly reduced the average birth weight after 35 weeks of gestation. It increased the risk of perinatal death by 24%. This increase was concentrated in the age groups under 25 and 35 +, in the parity groups 0 and 4 + and among women with less than 12 years of schooling. The proportion of mothers smoking during pregnancy was 43.2% and ranged as high as 62.2% among those under 20 with less than eight years of schooling. These depressingly high percentages imply that new educational approaches aimed particularly at high-risk groups should be developed and evaluated.     

Aetiology of testicular cancer: association with congenital abnormalities,age at puberty,infertility, and exercise. United Kingdom Testicular Cancer Study Group.

OBJECTIVE--To determine the risk of testicular cancer associated with undescended testis, inguinal hernia, age at puberty, marital status, infertility, vasectomy, and amount of exercise. DESIGN--A population based case-control study with a questionnaire administered by an interviewer and with relevant supplementary data extracted from general practitioners'' notes. SETTING--Nine health regions within England and Wales. SUBJECTS--794 men, aged 15-49 years, with a testicular germ cell tumour diagnosed between 1 January 1984 and 1 January 1987; each had an age matched (within one year) control selected from the list of their general practitioner. RESULTS--There was a significant association of testicular cancer with undescended testis (odds ratio 3.82; 95% confidence interval 2.24 to 6.52) and inguinal hernia (1.91; 1.12 to 3.23). The excess risk associated with undescended testis was eliminated in men who had had an orchidopexy before the age of 10 years. There were positive associations with early age at voice breaking, early age at starting to shave, and infertility. There was a significant association with a sedentary lifestyle and a moderate protective effect of exercise. There was no association with vasectomy. CONCLUSION--This study confirms previous reports that developmental urogenital abnormalities result in an increased risk of testicular cancer. The trend to perform orchidopexy at younger ages may reduce the risk associated with undescended testis. The increased risks associated with early age at puberty and low amounts of exercise may be related to effects of exposure to endogenous hormones. Changes in both of these factors may partly contribute to the increasing rates of testicular cancer observed in the past few decades.     

The influence of vasovasostomy on antisperm antibodies in rats

Serum antisperm antibodies were studied in Sprague-Dawley rats after vasectomy and vasovasostomy. Animals received a bilateral vasectomy, a vasectomy followed 3 mo later by vasovasostomy, or sham operations. Blood samples were obtained at 1, 3, 4, and 7 mo, and antisperm antibodies were assayed by an enzyme-linked immunosorbent assay. After vasectomy reversal was performed at 3 mo, antisperm antibodies were significantly higher in rats in the vasovasostomy group at 4 mo than in animals that had a persisting vasectomy or sham operations. At 7 mo, the antisperm antibody level for the vasovasostomy group was approximately double that for the vasectomized rats. Spermatic granulomas occurred in 76% of rats after vasovasostomy. Antisperm antibody levels were higher in vasovasostomized animals with granulomas than in those lacking granulomas. The results suggest that vasovasostomy may stimulate an antibody response to sperm rather than lead to a reduced response, as was anticipated upon removal of the obstruction. Spermatic granulomas may serve as sires for continued antigenic challenge. The observed increase in antisperm antibodies after vasovasostomy in Sprague-Dawley rats may be related to their relatively low immunologic responsiveness to vasectomy, with vasovasostomy serving as a second major immunologic challenge, aided by the formation of an additional granuloma. In the more responsive Lewis strain, we previously observed a rise in antisperm antibodies after the initial vasectomy, with no further increase after vasovasostomy.     

The relation between antisperm antibodies and testicular alterations after vasectomy and vasovasostomy in Lewis rats

The relationship between antisperm antibodies as determined by enzyme-linked immunosorbent assay (ELISA) and the occurrence of alterations in testicular weight and histology was studied following vasectomy in Lewis rats. The effects of vasovasostomy on antisperm antibody levels were also examined. At 1, 3, and 4 months after vasectomy, the mean absorbance values in an ELISA for sera from animals with altered testes was significantly greater than that from animals lacking testicular alterations. However, animals showing positive antisperm antibody responses were represented both in the group with testicular alterations and among those that lacked testicular damage. Levels of antisperm antibody in both vasectomy and vasovasostomy groups significantly exceeded that for sham-operated animals, but the level of antisperm antibodies in vasovasostomized animals with positive responses was similar to vasectomized animals one and four months after reanastomosis. It is suggested that persistence of antisperm antibodies or testicular alterations, or both, may play roles in limiting the restoration of fertility after vasovasostomy.     

Estudio preliminar de la efectividad de la terapia asistida con perros en personas de la tercera edad

IntroductionAnimal-assisted therapy is increasingly present in several educational and health areas. The aim of this study is to assess the effectiveness of such interventions in the elderly population living in residential settings.Materials and methodsA 12-week dog-assisted intervention program was designed, with 16 participants from a nursing home divided into an experimental group and a control group.ResultsSeveral physical and psychological variables were assessed before and after the intervention. While there were no significant differences in the control group, the experimental group improved significantly after participating in the program.DiscussionThe results support the hypothesis that animal-assisted interventions may be beneficial for residents in elderly care homes.