Exercise training and atrial fibrillation: a systematic review and literature analysis

OBJECTIVE

There are concerns in maintaining adequate levels of physical activity in patients with atrial fibrillation (AF). This could be related to the type of exercise delivered, different among studies, as the words used to describe it as treatment. We have analysed the state-of-art of the role of the exercise in AF by a mathematical analysis. This analysis documented the connections between topics and updated the available evidence through a systematic review of the current literature.

MATERIALS AND METHODS

A literature search was conducted using specific terms for studies published between 2000 and 2019. For the descriptive analysis of the current literature, we used the LExical Network analysed by the Graph THeory (LENGTH) method, while to perform our review we followed the PRISMA statement. Downs and Black Quality Index was also used to assess the quality of studies. The LENGTH approach indicated nonspecific terms as "exercise", "physical" and "activity" as more representative than "rehabilitation" to describe the intervention.

RESULTS

The systematic review identified nine studies on 882 patients of moderate (n=4) to good (n=5) quality. Training consisted of a combination of supervised ambulatory and home-based outpatient programs, focused on aerobic elements (endurance and resistance training, walking, treadmill and bicycle ergometer). Significant improvements in 6-minute walking test distance and peak oxygen uptake and in quality of life were obtained, with high adherence to training and no serious/significant adverse events. Only one trial was based on cardiac rehabilitation principles.

CONCLUSIONS

Adequate exercise training can get a favourable cardiovascular outcome in patients with AF.

Testicular function and prolactin responsiveness to TRH and cimetidine after renal transplantation

The hypothalamic-pituitary-testicular axis and the regulation of prolactin secretion were investigated in eleven male renal transplant recipients. Mean serum levels of testosterone and estrone were normal, whereas those of androstenedione and estradiol were low. Mean basal luteinizing hormone (LH) levels were slightly elevated, but the peak responses to 50 micrograms i.v. gonadotropin-releasing hormone (GnRH) were not dissimilar from controls. Both basal and GnRH-stimulated follicle-stimulating hormone (FSH) levels were elevated (p less than 0.02-0.05) and also positively correlated with the time spent on hemodialysis (p less than 0.005-0.002). Basal prolactin (PRL) levels were normal, in all subjects. Nine out of 11 patients had a normal PRL response to Thyrotropin-releasing Hormone (TRH). However only six out of 11 had a normal response to 200 mg i.v. Cimetidine (Cim). Three subjects normally responding to TRH failed to respond to Cim. Uremic primary hypogonadism is not fully reversed by renal transplantation: a slight defect in the pituitary LH release may persist and the impairment of the tubular testicular function is left unchanged. While uremic hyperprolactinemia is corrected, the responsiveness to PRL-stimulating agents, particularly Cim, is not restored to normal, reflecting a derangement at the pituitary as well as the hypothalamic level.

Hyperprolactinemia and psychological distress in women undergoing chronic hemodialysis

In order to investigate the possible relationship of hyperprolactinemia to psychological distress in patients undergoing chronic hemodialysis, 19 uremic women were evaluated by a semistructured interview and administered the Kellner Symptom Questionnaire. Group A (10 uremic women with hyperprolactinemia) did not differ significantly in anxiety, depression, somatization and hostility from group B (9 normoprolactinemic uremic women). Both groups rated themselves more depressed and hostile than a normal control group of 10 women, and hyperprolactinemic patients were also significantly more anxious than the normal controls.

Male hypogonadism of uremic patients on hemodialysis

Primary hypogonadism occurring among uremic men on hemodialysis has been widely investigated, yet few data are available concerning the general pattern of steroidogenesis. In 161 hemodialysis patients and in 83 healthy subjects, serum levels of gonadotropins (LH and FSH), prolactin (PRL), testosterone (T), androstenedione (A), estrone (E1), estradiol (E2), and dehydroepiandrosterone-sulphate (DHEA-S) were assessed through RIA methods. Mean +/- SD hormone levels were: LH 45.6 +/- 41.1 mIU/ml, FSH 16.3 +/- 16 mIU/ml, PRL 42.4 +/- 69.1 ng/ml, A 0.83 +/- 0.27 ng/ml, E1 64.3 +/- 31.7 pg/ml, all higher than controls; T 289 +/- 125 ng/100 ml, E2 11.8 +/- 3 pg/ml, and DHEA-S 1.4 +/- 1.4 micrograms/ml, all lower than controls. The A/T and E1/E2 ratios were also higher than controls and showed a good positive linear correlation (r = 0.40; p less than 0.001) between each other. The uremic damage acts at the testis level, impairing the activity of the enzyme 17-beta-hydroxysteroid-dehydrogenase (17-OHSD), even if a derangement of the peripheral interconversion between steroids cannot be excluded.

Effect of short and long-term administration of lisuride in Cushing's disease

To define the role of dopaminergic drugs on pituitary ACTH secretion, we studied the effect of a dopamine-agonist, lisuride, on a group of 9 patients with pituitary dependent Cushing's syndrome. Lisuride (0.4-0.6 mg/day) was administered for two days: in only two out of eight cases the ACTH levels, sampled every 30 min for 6 h (08:00-14:00 h), showed some reduction when compared with the control day. Two of the nonresponders (R.P.; B.F.) and one untested patient (L.E.) were then treated chronically with a similar amount of lisuride per day for 20 days (L.E.) and for 4 months (B.F.; R.P.). One patient (L.E.) showed a clear decrease in urinary free cortisol without clinical improvement; while in the other two cases, followed for a longer period of time, a clinical improvement was observed together with a decrease of the hormonal parameters. In conclusion, lisuride may occasionally reduce ACTH secretion in patients with pituitary dependent Cushing's syndrome, but the acute test fails to identify the patients who would benefit from this treatment.

Effect of hyperprolactinemia and age on the hypogonadism of uremic men on hemodialysis

Primary hypogonadism has been commonly reported among uremic men on hemodialysis, characterized by low testosterone levels, increased luteinizing hormone and sometimes follicle-stimulating hormone levels. Little is known about the influence of hyperprolactinemia and age on this hypogonadism. In 149 hemodialysis patients and in 60 healthy subjects the serum levels of testosterone (T), gonadotropins (LH and FSH) and prolactin (PRL) were assessed through radioimmunoassay. Mean +/- SD hormone levels were: T 274 +/- 125 ng/100 ml, lower than controls; LH 44.7 +/- 46.1 mlU/ml and FSH 17.6 +/- 18.4 mIU/ml, both higher than controls. PRL 31.3 +/- 49.4 ng/ml, higher than controls. A positive correlation between LH and FSH, a negative correlation between PRL and both T and LH was found. Moreover T and FSH were correlated with age only in the normoprolactinemic patients. These data suggest: a common damaging mechanism by uremia on both interstitial and tubular structures of the testis; a central antigonadal influence of hyperprolactinemia even if a direct action on the testis cannot be excluded; a worsening action of age on the gonadal function of these patients.

Hyperprolactinemia and sexual disturbances among uremic women on hemodialysis

The investigation of a sample of 99 women on maintenance hemodialysis has shown the presence of sexual disturbances to a great extent: the rate of sexual intercourse and the ability to reach orgasm were significantly lower than in age-matched control women. 80% declared a reduction in their sexual desire and the frequency of intercourse was also lower as compared to the period prior to dialysis. Ageing decreased the sexual activity in both the ill and healthy population, but in uremic patients the sexual activity ended at an earlier age. The patients with hyperprolactinemia reported lower frequencies of intercourse and lower percentages of orgasm than normoprolactinemic ones. The incidence of sexual dysfunction and the role of hyperprolactinemia in this respect were similar to those which are found among male patients on hemodialysis.

Pituitary microadenomas: surgical results and morphological findings

The results of transsphenoidal microsurgery in treating 22 patients with pituitary microadenomas are reported. Histological and ultrastructural comparative studies were performed in attempting to obtain a more accurate morphological classification of pituitary microadenomas.

Psychosomatic aspects of hyperprolactinemia

A review of some recent studies on the psychosomatic aspects of hyperprolactinemia is presented. Women seem to be more prone to suffer from the behavioral effects of prolactin than males. Women with hyperprolactinemic amenorrhea rated themselves significantly more hostile, more depressed and more anxious than women with amenorrhea only and other control groups. Hyperprolactinemic males did not rate themselves more hostile and depressed than matched controls. Psychological distress and hostility appear to remit upon treatment with bromocriptine. Postpartum patients matched for prolactin levels with hyperprolactinemic women showed significantly less depression and anxiety but about the same levels of hostility. Hostility, depression and loss of libido may coexist in the same hyperprolactinemic patient but they may be also present independently.

Psychological correlates of hyperprolactinemia in males

In a previous study with hyperprolactinemic female patients, self-rated hostility, depression and anxiety were significantly higher than in other female patients. The study was repeated in hyperprolactinemic males, using the same psychological assessments. Hyperprolactinemic males were significantly more anxious but did not differ significantly in hostility and depression from other male patients. The findings support the view that the psychological effects of high serum prolactin levels depend in part on interactions with gonadal hormones.

Depression and hostility in hyperprolactinemia

1. Patients with hyperprolactinemia offer a unique opportunity to investigate the effects of prolactin on psychological states. Women with hyperprolactinemic amenorrhea rated themselves significantly more hostile, more depressed and more anxious than women with amenorrhea only and normal women. 2. The hyperprolactinemic patients were compared with a group of post-partum (7th day) women, matched for sociodemographic variables and prolactin levels. The post-partum women showed significantly less depression and anxiety than those with hyperprolactinemic amenorrhea but about the same levels of hostility. 3. Hyperprolactinemic males did not rate themselves more hostile and depressed than matched controls.

Depression hostility and anxiety in hyperprolactinemic amenorrhea

In order to evaluate the relationship of psychological distress to hyperprolactinemia, 20 patients with secondary amenorrhea were evaluated by a semi-structured research interview and administered the Kellner Symptom Questionnaire. Group A (10 patients with amenorrhea and hyperprolactinemia) reported significantly more symptoms of depression, hostility and anxiety than group B (10 patients with amenorrhea and normal basal levels of plasma prolactin). Both groups were significantly more anxious, depressed and reported more somatic symptoms than a normal control group (n = 10). 6 of the 10 patients in group A reported decrease in libido, while this was found only in 1 of the 10 patients of group B. The findings suggest that the syndrome of depression, hostility and anxiety in a woman complaining of amenorrhea, especially if associated with decreased libido and galactorrhea, can be a manifestation of hyperprolactinemia.