Chronic use of opioids and the endocrine system.

Opioids are widely used for the management of acute and chronic pain. They are also abused for recreational purposes. Long term use may lead to abnormalities in the endocrine system. The axis mainly affected is the gonadal axis leading to hypogonadism. However adrenal insufficiency and growth hormone deficiency can also occur with evidence that other hormones are affected to a lesser extent. No large randomised controlled trials have been performed; however, evidence from several small studies on heroin addicts and chronic pain patients support the above. Hence it is important to consider hormonal abnormalities in patients on long term opioids and if suspected appropriate assessment would be warranted.

Circadian hydrocortisone infusions in patients with adrenal insufficiency and congenital adrenal hyperplasia.

OBJECTIVE: Conventional hydrocortisone therapy in adrenal insufficiency cannot provide physiological replacement. We have explored the potential of circadian delivery of hydrocortisone as proof of concept for such therapy delivered in modified-release tablet formulation. METHODS: We investigated whether the circadian intravenous infusion of hydrocortisone could improve control of ACTH and androgen levels. Two healthy subjects, two patients with Addison's disease and two patients with congenital adrenal hyperplasia (CAH) were studied. RESULTS: In patients on thrice daily oral hydrocortisone, peak serum cortisol levels were higher than in normal subjects and overnight levels were very low. Patients had very high plasma ACTH levels before their morning dose of hydrocortisone, both at the beginning and at the end of their conventional oral therapy: mean +/- SEM 311.8 +/- 123.2 and 311.2 +/- 85.4 ng/l, respectively. In the patients with CAH, serum 17-hydroxyprogesterone levels were also elevated: 550 and 642 nmol/l at the beginning and 550 and 777 nmol/l at the end of conventional treatment, respectively. The overall 24-h mean cortisol levels were similar for conventional oral hydrocortisone and the circadian infusion. At 0700 h, ACTH levels were much higher on conventional treatment than after circadian infusion: mean +/- SEM 311.2 +/- 85.4 vs. 70.5 +/- 45.0 ng/l, respectively (P < 0.05). The same pattern was observed in 17-hydroxyprogesterone levels, which were 550 and 777 nmol/l after conventional treatment and 3 and 64 nmol/l after circadian infusion. CONCLUSIONS: In patients with poor biochemical control of Addison's disease and CAH, a 24-h circadian infusion of hydrocortisone can decrease morning ACTH and 17-hydroxyprogesterone levels to near normal.

Double-blind placebo-controlled study of testosterone patch therapy on bone turnover in men with borderline hypogonadism.

Clinical studies suggest there may be a threshold concentration of serum testosterone below which replacement will result in skeletal and psychological benefit. We evaluated the response to testosterone in men with borderline hypogonadism. A randomized double-blind placebo-controlled trial in 39 men over age 40 years presenting with sexual dysfunction and a borderline low testosterone level (total testosterone <10 nmol/L or free androgen index <30%). Patients were randomized to Testoderm TTS body patch (5 mg/day, n = 20) or a placebo patch (n = 19) for 6 months, followed by open-label testosterone replacement for a further 6 months in all patients. During the placebo-controlled phase of the study serum testosterone increased significantly on testosterone vs. placebo treatment (p = 0.004); this was associated with a decrease in total body fat mass (p = 0.019) and increase in haemoglobin level (p = 0.036). There were no significant changes in lean body mass, markers of bone turnover, and measures of bone mineral density (BMD). There was evidence of difference in quality of life according to the Male Erectile Dysfunction Quality of Life questionnaire (MEDQoL score, p = 0.017), mainly accounted for by deterioration in the placebo arm. When the active treatment period was combined for placebo and testosterone groups, the within-patient analysis showed a significant effect of testosterone to decrease markers of bone resorption (uNTX/Cr, p = 0.007; iFDPD/Cr, p = 0.0006) and to increase lean body mass (p = 0.001). There was little convincing evidence from this study that testosterone replacement is likely to have major benefit in men over age 40 years with borderline hypogonadism and sexual dysfunction. However, there was evidence of suppression in bone resorption and hence longer and larger studies are needed to examine its effect on BMD.

Patients with chronic pain and abnormal pituitary function require investigation.

Misuse of opioids is associated with abnormalities of pituitary function. Patients with chronic pain frequently complain of fatigue and undergo endocrine testing. To test whether oral opioid treatment causes abnormal pituitary function we prospectively assessed pituitary function in 37 patients with chronic pain who were receiving either oral opioid analgesia or non-opioid analgesia. Oral opioid treatment was not associated with abnormal pituitary function although a few patients had abnormal results mainly related to obesity. Our results suggest that patients with chronic pain who have abnormal endocrine results should have a complete assessment, since abnormal test results cannot be attributed to their analgesia.

Modern treatment of acromegaly.

Acromegaly is an endocrine disorder characterised by increased morbidity and mortality. It is usually caused by a growth hormone secreting pituitary adenoma and is manifested by a variety of clinical features. Surgery is usually the treatment of choice, however over the last few years, several new methods of treatment have been developed. A recent consensus on the targets for treatment has led to multiple studies being conducted to assess the efficacy of the currently available options. This review examines the evidence for and against these treatments.