The growth hormone/insulin-like growth factor-I axis hormones and bone markers in elite athletes in response to a maximum exercise test.

The aim of the GH-2000 project is to develop a method for detecting GH doping among athletes. Previous papers in the GH-2000 project have proposed that a forthcoming method to detect GH doping will need specific components from the GH/IGF-I axis and bone markers because these specific variables seem more sensitive to exogenous GH than to exercise. The present study examined the responses of the serum concentrations of these specific variables to a maximum exercise test in elite athletes from selected sports. A total of 117 elite athletes (84 males and 33 females; mean age, 25 yr; range, 18-53 yr) from Denmark, the United Kingdom, Italy, and Sweden participated in the study. The serum concentrations of total GH, GH22 kDa, IGF-I, IGF binding protein (IGFBP)-2, IGFBP-3, acid-labile subunit, procollagen type III (P-III-P), and the bone markers osteocalcin, carboxy-terminal cross-linked telopeptide of type I collagen (ICTP), and carboxy-terminal propeptide of type I procollagen were measured. The maximum exercise test showed, in both genders, a peak concentration of total GH (P < 0.001) and GH22 kDa (P < 0.001) by the time exercise ended compared with baseline, and a subsequent decrease to baseline levels within 30-60 min after exercise. The mean time to peak value for total GH and GH22 kDa was significantly shorter in males than females (P < 0.001). The components of the IGF-I axis showed a similar pattern, with a peak value after exercise compared with baseline for IGF-I (P < 0.001, males and females); IGFBP-3 (P < 0.001, males and females); acid-labile subunit [P < 0.001, males; not significant (NS), females], and IGFBP-2 (P < 0.05, females; NS, males). The serum concentrations of the bone markers ICTP (P < 0.001, males; P < 0.05, females) and P-III-P (P < 0.001, males and females) increased in both genders, with a peak value in the direct post-exercise phase and a subsequent decrease to baseline levels or below within 120 min. The osteocalcin and propeptide of type I procollagen values did not change during the exercise test. Specific reference ranges for each variable in the GH/IGF-I axis and bone markers at specific time points are presented. Most of the variables correlated negatively with age. In summary, the maximum exercise test showed a rather uniform pattern, with peak concentrations of the GH/IGF-I axis hormones and the bone markers ICTP and P-III-P immediately after exercise, followed by a subsequent decrease to baseline levels. The time to peak value for total GH and GH22 kDa was significantly shorter for females compared with males. This paper presents reference ranges for each marker in each gender at specific time points in connection to a maximum exercise test to be used in the development of a test for detection of GH abuse in sports.

Care-seeking behavior for upper respiratory infections.

BACKGROUND: Many recent efforts to reduce unnecessary medical services have targeted care of upper respiratory infections (URIs). We tested whether patients who seek care very early in their illness differ from those who seek care later and whether they might require a different approach to care. METHODS: We surveyed by telephone 257 adult patients and 249 parents of child patients who called or visited one of 3 primary care clinics within 10 days (adults) or 14 days (parents) of the onset of uncomplicated URI symptoms. Those who contacted the clinic within the first 2 days of illness were compared with those who made contact later. RESULTS: Although 28% of adults and 41% of parents contacted their clinic within the first 2 days of symptom onset, we found very few differences in the characteristics of the caller or patient between those who called early and later. The illnesses of those who called early were not more severe, and they did not have different beliefs, histories, approaches to medical care, or needs. The only clinician-relevant difference was that adult patients calling in the first 2 days had a greater desire to rule out complications (84.7% vs 64.1% calling in 3-5 days and 70.6% calling after 5 days of illness, P < or = .05). CONCLUSIONS: Those who seek medical care very early for a URI do not appear to be different in clinically important ways. If we are going to reduce overuse of medical care and antibiotics for URIs, clinical trials of more effective and efficient strategies are needed to encourage home care and self-management.

The physician's role in educating patients. A comparison of mailed versus physician-delivered patient education.

BACKGROUND: Patients value receiving educational information during office visits, but physicians often lack the time or training to satisfy this need. We examined whether an increased physician role in educating patients is an effective means of improving patient satisfaction. METHODS: Using a nonrandomized controlled research design, we compared patient satisfaction with self-care information provided by traditional direct-mail approaches and by physicians during routine office visits. We also studied a control group of patients receiving usual care. RESULTS: Patients who received a medical self-care book from a physician were significantly more likely to be satisfied with their office visit than those who received the book in the mail or those who experienced usual care. The intervention group reported greater satisfaction with 11 out of 13 variables related to physician-patient communication and quality of care. There were no significant differences between the control group and the direct-mail group. CONCLUSIONS: The patients who received self-care information from their physicians were significantly more satisfied with their care and their physician-patient communication experience than those in either the direct-mail group or the control group. Our findings lend support to the growing evidence that patients informed by their physicians are more satisfied with their care.

Cataract surgery outcomes: importance of co-morbidities in case mix.

Variation in patients' preoperative co-morbidities can have a significant effect on the outcomes of cataract surgery. To examine the effects of that variation, we did a retrospective study of the outcomes of extracapsular cataract surgery performed by seven surgeons. Medical records from 791 surgeries done from June 1, 1986, through May 31, 1989, were retrospectively examined. Variations in postoperative visual acuity and intraoperative and postoperative complications were documented. The relationships between preoperative ocular and systemic medical co-morbidities and postoperative visual results and complications were studied. A statistical model was developed to adjust for the preoperative co-morbidity case mix between physicians. Visual acuity rates varied by surgeon and surgical volume, but not significantly when adjusted for patient case mix.

Prematurity prevention programs: an analysis of successes and failures.

OBJECTIVE: Our purpose was to assess the long-term results of established prematurity prevention programs. STUDY DESIGN: A population cohort of pregnant women from two major urban health care organizations were examined. Rates and cost-benefit analysis of prematurity and patient, system, or physician failures were analyzed. During 1990 1143 pregnant women were prospectively reviewed. RESULTS: A total of 11.8% of the mothers were high risk and responsible for 108 (50.2%) of the preterm deliveries. The preterm birth rate of all enrollees was 4.6%. One percent of the preterm neonates required level III care for complications. The average charge for a 35 week infant was 18 times, and a 36 week infant was five times more costly than a term infant. Patient, physician, and health care system failures occurred at different rates. CONCLUSIONS: This preterm prevention program resulted in low preterm birth rates. Potentially preventable preterm births most often occurred as a result of patient and physician failures.

Nicotine vs placebo gum in general medical practice.

Three hundred fifteen smokers who attended a family practice clinic and wished to quit smoking were assigned in a random, double-blind manner to receive either nicotine (2 mg) or placebo gum. Smokers initially received brief advice from a physician and nurse, a slide presentation and written materials (29 to 35 minutes), and a single follow-up visit (12 to 20 minutes) one week after cessation. After corrections for marital status and income, 10% of those who received nicotine gum and 7% of those who received placebo gum reported continuous abstinence for 11 months and passed observer and biochemical verification (this difference was not statistically significant). We conclude that, when used in a nonselected group of smokers along with a brief intervention in a general medical practice, the pharmacologic effects of nicotine gum to increase cessation are either small or nonexistent.

Diazepam dose preference in humans.

Diazepam dose preference was studied in 10 human subjects in a hospital setting. Subjects were allowed to select between a standard compound (diazepam or pentobarbital) and one of several doses of diazepam (2-40 mg/capsule) on an ad lib basis. When 5 or 10 mg/capsule diazepam was the standard, no clear cut diazepam dose preference was found. When 30 or 50 mg/capsule pentobarbital was the standard, clear cut diazepam dose preference in some subjects was found. The shape of the dose preference function differed among subjects. Within subjects, diazepam dose preference differed within the self-administration day, with some subjects preferring one dose in the morning and a different dose later in the day.

Joint effects of d-amphetamine and ethanol or pentobarbital in pigeons.

Drug interactions were examined in pigeons keypecking under a multiple fixed ratio 30-response, fixed interval 5-minute (mult FR 30, FI 5-min) schedule of food presentation. Low to intermediate doses of d-amphetamine attenuated the rate-decreasing effects of ethanol under both components of the multiple schedule; however, these same doses of d-amphetamine seldom attenuated the rate-decreasing effects of pentobarbital. Increases in rates of responding produced by ethanol or pentobarbital under FI components were often enhanced following low to intermediate doses of d-amphetamine. Higher doses of d-amphetamine generally enhanced the rate-decreasing effects produced by either ethanol or pentobarbital alone. Results indicate that the joint effects of two drugs cannot be predicted from a knowledge of either their individual or their rate-dependent effects.

Joint effects of ethanol and caffeine on schedule-controlled responding in the pigeon.

Interactions between ethanol and caffeine were studied in pigeons keypecking under a multiple fixed ratio 30 fixed interval 5-min schedule of food presentation. When ethanol was administered alone, rates of responding under both components of the multiple schedule were generally decreased in a dose-related manner. Caffeine alone either decreased or had no effect on rates of responding under both the fixed ratio and fixed interval components. When caffeine and ethanol were combined, doses of caffeine which did not decrease rates of responding when given alone attenuated the rate-decreasing effects of ethanol.

Some effects of delta-amphetamine and pentobarbital on performance under a long fixed-interval schedule.

The effects of delta-amphetamine and pentobarbital were studied on performance during 3-hr sessions under fixed-interval 60-min schedules of food presentation. Low doses of delta-amphetamine increased rates of responding and higher doses decreased rates of responding, both during the entire 3-hr session and during each of the individual fixed intervals. Pentobarbital produced little effect on rates of responding averaged over the 3-r session, but it decreased rates during the first fixed interval and increased them during the second and third fixed intervals. The effects of delta-amphetamine were shown to be dependent on the control rate of responding, as has been shown with shorter fixed-interval values. Analysis of delta-amphetamine effects in terms of the point at which the probability of responding is greater than zero was not descriptive of overall fixed-interval performance.