Econstudentlog

Depression (II)

I have added some more quotes from the last half of the book as well as some more links to relevant topics below.

“The early drugs used in psychiatry were sedatives, as calming a patient was probably the only treatment that was feasible and available. Also, it made it easier to manage large numbers of individuals with small numbers of staff at the asylum. Morphine, hyoscine, chloral, and later bromide were all used in this way. […] Insulin coma therapy came into vogue in the 1930s following the work of Manfred Sakel […] Sakel initially proposed this treatment as a cure for schizophrenia, but its use gradually spread to mood disorders to the extent that asylums in Britain opened so-called insulin units. […] Recovery from the coma required administration of glucose, but complications were common and death rates ranged from 1–10 per cent. Insulin coma therapy was initially viewed as having tremendous benefits, but later re-examinations have highlighted that the results could also be explained by a placebo effect associated with the dramatic nature of the process or, tragically, because deprivation of glucose supplies to the brain may have reduced the person’s reactivity because it had induced permanent damage.”

“[S]ome respected scientists and many scientific journals remain ambivalent about the empirical evidence for the benefits of psychological therapies. Part of the reticence appears to result from the lack of very large-scale clinical trials of therapies (compared to international, multi-centre studies of medication). However, a problem for therapy research is that there is no large-scale funding from big business for therapy trials […] It is hard to implement optimum levels of quality control in research studies of therapies. A tablet can have the same ingredients and be prescribed in almost exactly the same way in different treatment centres and different countries. If a patient does not respond to this treatment, the first thing we can do is check if they receive the right medication in the correct dose for a sufficient period of time. This is much more difficult to achieve with psychotherapy and fuels concerns about how therapy is delivered and potential biases related to researcher allegiance (i.e. clinical centres that invent a therapy show better outcomes than those that did not) and generalizability (our ability to replicate the therapy model exactly in a different place with different therapists). […] Overall, the ease of prescribing a tablet, the more traditional evidence-base for the benefits of medication, and the lack of availability of trained therapists in some regions means that therapy still plays second fiddle to medications in the majority of treatment guidelines for depression. […] The mainstay of treatments offered to individuals with depression has changed little in the last thirty to forty years. Antidepressants are the first-line intervention recommended in most clinical guidelines”.

“[W]hilst some cases of mild–moderate depression can benefit from antidepressants (e.g. chronic mild depression of several years’ duration can often respond to medication), it is repeatedly shown that the only group who consistently benefit from antidepressants are those with severe depression. The problem is that in the real world, most antidepressants are actually prescribed for less severe cases, that is, the group least likely to benefit; which is part of the reason why the argument about whether antidepressants work is not going to go away any time soon.”

“The economic argument for therapy can only be sustained if it is shown that the long-term outcome of depression (fewer relapses and better quality of life) is improved by receiving therapy instead of medication or by receiving both therapy and medication. Despite claims about how therapies such as CBT, behavioural activation, IPT, or family therapy may work, the reality is that many of the elements included in these therapies are the same as elements described in all the other effective therapies (sometimes referred to as empirically supported therapies). The shared elements include forming a positive working alliance with the depressed person, sharing the model and the plan for therapy with the patient from day one, and helping the patient engage in active problem-solving, etc. Given the degree of overlap, it is hard to make a real case for using one empirically supported therapy instead of another. Also, there are few predictors (besides symptom severity and personal preference) that consistently show who will respond to one of these therapies rather than to medication. […] One of the reasons for some scepticism about the value of therapies for treating depression is that it has proved difficult to demonstrate exactly what mediates the benefits of these interventions. […] despite the enthusiasm for mindfulness, there were fewer than twenty high-quality research trials on its use in adults with depression by the end of 2015 and most of these studies had fewer than 100 participants. […] exercise improves the symptoms of depression compared to no treatment at all, but the currently available studies on this topic are less than ideal (with many problems in the design of the study or sample of participants included in the clinical trial). […] Exercise is likely to be a better option for those individuals whose mood improves from participating in the experience, rather than someone who is so depressed that they feel further undermined by the process or feel guilty about ‘not trying hard enough’ when they attend the programme.”

“Research […] indicates that treatment is important and a study from the USA in 2005 showed that those who took the prescribed antidepressant medications had a 20 per cent lower rate of absenteeism than those who did not receive treatment for their depression. Absence from work is only one half of the depression–employment equation. In recent times, a new concept ‘presenteeism’ has been introduced to try to describe the problem of individuals who are attending their place of work but have reduced efficiency (usually because their functioning is impaired by illness). As might be imagined, presenteeism is a common issue in depression and a study in the USA in 2007 estimated that a depressed person will lose 5–8 hours of productive work every week because the symptoms they experience directly or indirectly impair their ability to complete work-related tasks. For example, depression was associated with reduced productivity (due to lack of concentration, slowed physical and mental functioning, loss of confidence), and impaired social functioning”.

“Health economists do not usually restrict their estimates of the cost of a disorder simply to the funds needed for treatment (i.e. the direct health and social care costs). A comprehensive economic assessment also takes into account the indirect costs. In depression these will include costs associated with employment issues (e.g. absenteeism and presenteeism; sickness benefits), costs incurred by the patient’s family or significant others (e.g. associated with time away from work to care for someone), and costs arising from premature death such as depression-related suicides (so-called mortality costs). […] Studies from around the world consistently demonstrate that the direct health care costs of depression are dwarfed by the indirect costs. […] Interestingly, absenteeism is usually estimated to be about one-quarter of the costs of presenteeism.”

Jakob Klaesi. António Egas Moniz. Walter Jackson Freeman II.
Electroconvulsive therapy.
Psychosurgery.
Vagal nerve stimulation.
Chlorpromazine. Imipramine. Tricyclic antidepressant. MAOIs. SSRIs. John CadeMogens Schou. Lithium carbonate.
Psychoanalysis. CBT.
Thomas Szasz.
Initial Severity and Antidepressant Benefits: A Meta-Analysis of Data Submitted to the Food and Drug Administration (Kirsch et al.).
Chronobiology. Chronobiotics. Melatonin.
Eric Kandel. BDNF.
The global burden of disease (Murray & Lopez) (the author discusses some of the data included in that publication).

January 8, 2018 Posted by | Books, Health Economics, Medicine, Pharmacology, Psychiatry, Psychology | Leave a comment

Endocrinology (part I – thyroid)

Handbooks like these are difficult to blog, but I decided to try anyway. The first 100 pages or so of the book deals with the thyroid gland. Some observations of interest below.

“Biosynthesis of thyroid hormones requires iodine as substrate. […] The thyroid is the only source of T4. The thyroid secretes 20% of circulating T3; the remainder is generated in extraglandular tissues by the conversion of T4 to T3 […] In the blood, T4 and T3 are almost entirely bound to plasma proteins. […] Only the free or unbound hormone is available to tissues. The metabolic state correlates more closely with the free than the total hormone concentration in the plasma. The relatively weak binding of T3 accounts for its more rapid onset and offset of action. […] The levels of thyroid hormone in the blood are tightly controlled by feedback mechanisms involved in the hypothalamo-pituitary-thyroid (HPT) axis“.

“Annual check of thyroid function [is recommended] in the annual review of diabetic patients.”

“The term thyrotoxicosis denotes the clinical, physiological, and biochemical findings that result when the tissues are exposed to excess thyroid hormone. It can arise in a variety of ways […] It is essential to establish a specific diagnosis […] The term hyperthyroidism should be used to denote only those conditions in which hyperfunction of the thyroid leads to thyrotoxicosis. […] [Thyrotoxicosis is] 10 x more common in ♀ than in ♂ in the UK. Prevalence is approximately 2% of the ♀ population. […] Subclinical hyperthyroidism is defined as low serum thyrotropin (TSH) concentration in patients with normal levels of T4 and T3. Subtle symptoms and signs of thyrotoxicosis may be present. […] There is epidemiological evidence that subclinical hyperthyroidism is a risk factor for the development of atrial fibrillation or osteoporosis.1 Meta-analyses suggest a 41% increase in all-cause mortality.2 […] Thyroid crisis [storm] represents a rare, but life-threatening, exacerbation of the manifestations of thyrotoxicosis. […] the condition is associated with a significant mortality (30-50%, depending on series) […]. Thyroid crisis develops in hyperthyroid patients who: *Have an acute infection. *Undergo thyroidal or non-thyroidal surgery or (rarely) radioiodine treatment.”

“[Symptoms and signs of hyperthyroidism (all forms):] *Hyperactivity, irritability, altered mood, insomnia. *Heat intolerance, sweating. […] *Fatigue, weakness. *Dyspnoea. *Weight loss with appetite (weight gain in 10% of patients). *Pruritus. […] *Thirst and polyuria. *Oligomenorrhoea or amenorrhoea, loss of libido, erectile dysfunction (50% of men may have sexual dysfunction). *Warm, moist skin. […] *Hair loss. *Muscle weakness and wasting. […] Manifestations of Graves’s disease (in addition to [those factors already mentioned include:]) *Diffuse goitre. *Ophthalmopathy […] A feeling of grittiness and discomfort in the eye. *Retrobulbar pressure or pain, eyelid lag or retraction. […] *Exophthalmos (proptosis) […] Optic neuropathy.”

“Two alternative regimens are practiced for Graves’s disease: dose titration and block and replace. […] The [primary] aim [of the dose titration regime] is to achieve a euthyroid state with relatively high drug doses and then to maintain euthyroidism with a low stable dose. […] This regimen has a lower rate of side effects than the block and replace regimen. The treatment is continued for 18 months, as this appears to represent the length of therapy which is generally optimal in producing the remission rate of up to 40% at 5 years after discontinuing therapy. *Relapses are most likely to occur within the first year […] Men have a higher recurrence rate than women. *Patients with multinodular goitres and thyrotoxicosis always relapse on cessation of antithyroid medication, and definite treatment with radioiodine or surgery is usually advised. […] Block and replace regimen *After achieving a euthyroid state on carbimazole alone, carbimazole at a dose of 40mg daily, together with T4 at a dose of 100 micrograms, can be prescribed. This is usually continued for 6 months. *The main advantages are fewer hospital visits for checks of thyroid function and shorter duration of treatment.”

“Radioiodine treatment[:] Indications: *Definite treatment of multinodular goitre or adenoma. *Relapsed Graves’s disease. […] *Radioactive iodine-131 is administered orally as a capsule or a drink. *There is no universal agreement regarding the optimal dose. […] The recommendation is to administer enough radioiodine to achieve euthyroidism, with the acceptance of a moderate rate of hypothyroidism, e.g. 15-20% at 2 years. […] In general, 50-70% of patients have restored normal thyroid function within 6-8 weeks of receiving radioiodine. […] The prevalence of hypothyroidism is about 50% at 10 years and continues to increase thereafter.”

“Thyrotoxicosis occurs in about 0.2% of pregnancies. […] *Diagnosis of thyrotoxicosis during pregnancy may be difficult or delayed. *Physiological changes of pregnancy are similar to those of hyperthyroidism. […] 5-7% of ♀ develop biochemical evidence of thyroid dysfunction after delivery. An incidence is seen in patients with type I diabetes mellitus (25%) […] One-third of affected ♀ with post-partum thyroiditis develop symptoms of hypothyroidism […] There is a suggestion of an risk of post-partum depression in those with hypothyroidism. […] *The use of iodides and radioiodine is contraindicated in pregnancy. *Surgery is rarely performed in pregnancy. It is reserved for patients not responding to ATDs [antithyroid drugs, US]. […] Hyperthyroid ♀ who want to conceive should attain euthyroidism before conception since uncontrolled hyperthyroidism is associated with an an risk of congenital abnormalities (stillbirth and cranial synostosis are the most serious complications).”

“Nodular thyroid disease denotes the presence of single or multiple palpable or non-palpable nodules within the thyroid gland. […] *Clinically apparent thyroid nodules are evident in ~5% of the UK population. […] Thyroid nodules always raise the concern of cancer, but <5% are cancerous. […] clinically detectable thyroid cancer is rare. It accounts for <1% of all cancer and <0.5% of cancer deaths. […] Thyroid cancers are commonest in adults aged 40-50 and rare in children [incidence of 0.2-5 per million per year] and adolescents. […] History should concentrate on: *An enlarging thyroid mass. *A previous history of radiation […] family history of thyroid cancer. *The development of hoarseness or dysphagia. *Nodules are more likely to be malignant in patients <20 or >60 years. *Thyroid nodules are more common in ♀ but more likely to be malignant in ♂. […] Physical findings suggestive of malignancy include a firm or hard, non-tender nodule, a recent history of enlargement, fixation to adjacent tissue, and the presence of regional lymphadenopathy. […] Thyroid nodules may be described as adenomas if the follicular cell differentiation is enclosed within a capsule; adenomatous when the lesions are circumscribed but not encapsulated. *The most common benign thyroid tumours are the nodules of multinodular goitres (colloid nodules) and follicular adenomas. […] Autonomously functioning thyroid adenomas (or nodules) are benign tumours that produce thyroid hormone. Clinically, they present as a single nodule that is hyperfunctioning […], sometimes causing hyperthyroidism.”

“Inflammation of the thyroid gland often leads to a transient thyrotoxicosis followed by hypothyroidism. Overt hypothyroidism caused by autoimmunity has two main forms: Hashimoto’s (goitrous) thyroiditis and atrophic thyroiditis. […] Hashimoto’s thyroiditis [is] [c]haracterized by a painless, variable-sized goitre with rubbery consistency and an irregular surface. […] Occasionally, patients present with thyrotoxicosis in association with a thyroid gland that is unusually firm […] Atrophic thyroiditis [p]robably indicates end-stage thyroid disease. These patients do not have goitre and are antibody [positive]. […] The long-term prognosis of patients with chronic thyroiditis is good because hypothyroidism can easily be corrected with T4 and the goitre is usually not of sufficient size to cause local symptoms. […] there is an association between this condition and thyroid lymphoma (rare, but risk by a factor of 70).”

“Hypothyroidism results from a variety of abnormalities that cause insufficient secretion of thyroid hormones […] The commonest cause is autoimmune thyroid disease. Myxoedema is severe hypothyroidism [which leads to] thickening of the facial features and a doughy induration of the skin. [The clinical picture of hypothyroidism:] *Insidious, non-specific onset. *Fatigue, lethargy, constipation, cold intolerance, muscle stiffness, cramps, carpal tunnel syndrome […] *Slowing of intellectual and motor activities. *↓ appetite and weight gain. *Dry skin; hair loss. […] [The term] [s]ubclinical hypothyroidism […] is used to denote raised TSH levels in the presence of normal concentrations of free thyroid hormones. *Treatment is indicated if the biochemistry is sustained in patients with a past history of radioiodine treatment for thyrotoxicosis or [positive] thyroid antibodies as, in these situations, progression to overt hypothyroidism is almost inevitable […] There is controversy over the advantages of T4 treatment in patients with [negative] thyroid antibodies and no previous radioiodine treatment. *If treatment is not given, follow-up with annual thyroid function tests is important. *There is no generally accepted consensus of when patients should receive treatment. […] *Thyroid hormone replacement with synthetic levothyroxine remains the treatment of choice in primary hypothyroidism. […] levothyroxine has a narrow therapeutic index […] Elevated TSH despite thyroxine replacement is common, most usually due to lack of compliance.”

 

January 8, 2018 Posted by | Books, Cancer/oncology, Diabetes, Medicine, Ophthalmology, Pharmacology | Leave a comment