Biomedical subjects

P R Close

Publications and source records attributed to P R Close.

6 recordsLinked to original sources

PubMed1999

Relationship of physical exercise and ageing to growth hormone production.

OBJECTIVE: The normal decline in physiological function with ageing is associated with a decrease in bioavailable growth hormone. Growth hormone has been shown to alter body composition and increase fat-free mass in older men. Increased physical fitness is accompanied by an increase in 24-h growth hormone release. The purpose of this study was to examine the effect of exercise on declining growth hormone concentrations with increasing age. DESIGN AND PATIENTS: The growth hormone production of 10 male subjects running over 40 miles per week was compared to 10 healthy age-matched sedentary males (controls 57.7 +/- 2.8 vs. runners 60.5 +/- 3.4 years). All subjects underwent a basal assessment including a two-hour serum growth hormone profile followed by estimation of maximal exercise capacity on a cycle ergometer with growth hormone estimations at peak exercise activity and every five minutes whilst cycling at 40% of maximal exercise capacity. RESULTS: Maximal exercise capacity confirmed the lifestyles of the two groups (VO2 max controls 22.36 +/-6.05 vs. runners 34.91 +/- 13.13 l/min/kg, P = 0.01). The runners had lower body-mass indices than controls (BMI 22. 3 +/- 1.5 vs. 25.5 +/- 2.0 kg/m2, P = 0.002). Peak growth hormone level during a two-hour resting profile was higher in the runners (median (range) controls 2.10 (0.20-12.20) vs. runners 5.25 (0.80-21. 00) mU/l, P = 0.03) as was the average growth hormone level during the two hour profile (mean growth hormone per 2 h median (range): controls 0.54 (0.03-4.88) vs. runners 2.17 (0.25-7.45) mU/l, P = 0. 04). Growth hormone production at maximal exercise capacity was similar. Sex hormone binding globulin and testosterone were significantly higher in the runners. CONCLUSIONS: The results suggest that regular intensive exercise in older male subjects is associated with higher growth hormone and testosterone levels and that exercise may have a role in counteracting the normal decline in growth hormone with ageing.

Aging↗

PubMed1999

Objective benefit of laser palatoplasty for non-apnoeic snoring.

Laser palatoplasty (LPP) is widely used for the treatment of non-apnoeic snoring, despite the lack of objective data supporting its use. We report measurements of snoring in a prospective study of LPP, and we compare the results with a previous study of uvulopalatopharyngoplasty (UPPP). Twenty patients with an apnoea/hypopnoea index < 20 h-1 underwent LPP for habitual snoring. Overnight sound recordings were compared before and 6 months after operation using three objective indices; L, (the level exceeded by the loudest 1% of sound), L5 (the level exceeded by the loudest 5% of sound) and P50 (% total sleep time above 50 dBA). The subjective impression of snoring severity (Wilcoxon test, P < 0.001), and objective indices L1 and P50 (t-test, P < 0.001) showed significant reductions after LPP. The mean change in L1 was 4.2 dBA, comparable to that we previously reported for UPPP, while P50 was reduced to less than one-third its preoperative value. No other sleep variables changed significantly following LPP. We conclude that LPP results in reduced snoring volume comparable to that following UPPP.

Acoustics↗

PubMed1999

Psychometric performance before and after laser palatoplasty for non-apnoeic snoring.

Psychometric tests are an objective way of examining cognitive functioning, and have shown impairment in patients with obstructive sleep apnoea. Non-apnoeic snoring may cause reduced concentration, but psychometric tests have been used rarely in this population. We investigate whether their use can demonstrate an improvement in cognitive performance in 20 non-apnoeic snorers following Laser Palatoplasty (LPP). The subjects completed psychometric tests, Beck Anxiety and Depression Inventories and an Epworth Sleepiness Scale on two occasions before LPP and once postoperatively. The only index to show any significant change with LPP was the Beck Depression Inventory (P < 0.005), which was reduced by a mean of 1.6 units following surgery. There was also a highly significant improvement in information processing between the preoperative tests, for which no explanation could be found. Our results suggest that commonly applied psychometric tests are unable to demonstrate significant improvements following surgery for non-apnoeic snoring. However, we have demonstrated for the first time a significant reduction in depression following surgery, which is evidence that snoring is more than a social nuisance.

Cognition↗

PubMed1995

Comparison of methods for assessing snoring.

Objective measurements of several sound level indices were made on 32 subjects referred because of snoring and who subsequently underwent uvulopalatopharyngoplasty (UPPP). The measurements were repeated approximately 6 months post-UPPP. The indices were compared with the subjective assessment of snoring by both the subject and his/her bed partner. Correlations between objective and subjective assessments were generally weak and were strongest when the supine posture only was considered. The index which correlated best with subjective assessment was the level which 1% of the sound level samples exceeded.

Abdomen↗

PubMed1995

Objective measurement of the results of uvulopalatopharyngoplasty.

Thirty-two patients undergoing uvulopalatopharyngoplasty (UPPP) for snoring have been studied prospectively using objective measurement of snoring levels. A significant reduction was found, especially in the supine posture. The quantitative reduction was small and correlations between subjective and objective changes in snoring volume were weak.

Adult↗

PubMed1994

The use of sound recording and oxygen saturation in screening snorers for obstructive sleep apnoea.

It is desirable to screen snoring patients for obstructive sleep apnoea (OSA) prior to surgical treatment. We postulated that the addition of a sound profile would increase the value of overnight oxygen saturation (SaO2) as a screening method. Thirty-nine polysomnographic studies including sound level measured by calibrated meter were performed on snorers being considered for uvulopalato-pharyngoplasty (UPPP). Polysomnography showed an apnoea/hypopnoea index (AHI) > or = 15 per hour of sleep in seven subjects. Two experienced observers independently, without knowledge of other data, classified paper records of SaO2 alone and SaO2 plus sound level obtained during polysomnography as OSA 'unlikely', 'equivocal' or 'definite'. The addition of sound to SaO2 reduced the number of equivocal results from 14 to six and increased the number classified as 'definite' or 'unlikely'. The sensitivity of oximetry +/- sound increased as the threshold AHI used in the definition of OSA increased; addition of sound improved recognition of mild OSA without impairing specificity.

Adult↗