5.2.4 Assessment of physical factors

Assessment of Physical Factors including Investigations

In psychiatric assessments, physical factors and investigations play an important role in helping healthcare professionals arrive at a diagnosis. These assessments include:

1. Physical examination: A general physical examination is performed to rule out any underlying medical conditions that could be contributing to the patient’s mental symptoms.
2. Vital signs: Vital signs such as blood pressure, heart rate, and body temperature are checked to ensure the patient’s overall health.
3. Laboratory tests: Blood tests, urine tests, and other laboratory tests may be conducted to look for any evidence of underlying medical conditions, such as infections, electrolyte imbalances, or endocrine disorders.
4. Neuroimaging studies: Neuroimaging studies, such as MRI or CT scans, may be performed to rule out brain conditions that could be contributing to mental symptoms, such as brain tumours, strokes, or degenerative diseases.
5. Electroencephalogram (EEG): An EEG may be performed to evaluate brain activity and look for evidence of seizures or other neurological conditions.
6. Psychophysiological tests: Psychophysiological tests, such as heart rate variability, electrodermal activity, or pupillometry, may be used to measure specific physiological responses to stimuli that are relevant to mental disorders.
7. Substance abuse tests: Substance abuse tests, such as urine or blood tests, may be performed to determine if the patient is using drugs or alcohol that could be contributing to their mental symptoms.

These physical factors and investigations are important in helping healthcare professionals arrive at a comprehensive and accurate diagnosis and develop an effective treatment plan for their patients.

Depression

Depression as a clinical diagnosis can present with a number of common chronic medical conditions. These include coronary artery disease, diabetes mellitus, renal disease, HIV, malignancies, neurological disorders, and stroke.

Before taking antidepressants, laboratory tests are often performed if medical causes are suspected or a baseline function needs to be determined.

Investigation	Purpose
FBC (plus CRP)	Infections or inflammatory causes
TSH	Hypothyroidism can present like depression
Vitamin B12	Deficiency can present like depression
Electrolytes (plus Ca2+, Mg2+, phosphate)	Fatigue or depression can present due to deficiencies
Renal function (eGFR, creatinine)	Prior to commencing antidepressants
LFTs	Prior to commencing antidepressants and rule out alcohol-related liver disease
Blood / Urine toxicology	Illicit substances can contribute to a depressive presentation
24 hr urinary free cortisol	If Cushing’s disease is suspected
ACTH stimulation test	If Addison’s disease is suspected
HIV and Syphilis	If sexually transmitted infections are suspected to contribute to mental state

Thyroid investigations:

Patients with thyroid disorders are more prone to develop depressive symptoms and conversely, depression may be accompanied by various subtle thyroid abnormalities.

• 1-5% of depressed patients presenting with depressive symptoms show hypothyroidism.
• 4-40% show subclinical hypothyroidism.
• Both hypothyroidism and subclinical hypothyroidism can contribute to treatment failure.
• Reductions in serum T4 may be associated with:
  • Antidepressants
  • Lithium
  • Sleep deprivation
  • Electroconvulsive therapy
• Approximately 30% of patients presenting with clinical depression show blunted TSH response.

Anxiety

Living with chronic anxiety can cause physical stress on your body, especially to your nervous, cardiovascular, digestive, immune, and respiratory systems. Research usually cannot address the direct causal relationship between a physical ailment and a mood disorder due to the lack of adequate study designs, methodologies, and population samples. What can be understood is the wide association and impact of mood disorders on a variety of physical illnesses.

Anxiety disorder is partly a diagnosis of exclusion. Excluding physical health conditions, other psychiatric disorders, medication side effects, or other substance use.

Physical examination and laboratory studies are generally normal if no co-existing issue is noted.

Diagnostic possibilities for anxiety or ‘panic attacks’ include paroxysmal atrial tachycardia, pulmonary embolus, seizure disorder, Meniere’s disease, transient ischemic attack, carcinoid syndrome, Cushing’s disease, hyperthyroidism, hypoglycemia, and pheochromocytoma. A physical examination is warranted for all first presentations; extensive medical evaluation for these disorders is indicated only when other features suggest physical disease. 

Psychosis

When presented with a patient who is suffering from suspected psychosis always consider physical health differential diagnosis and assess for a range of other factors:

Investigation	Purpose
FBC (plus CRP)	Infections or inflammatory causes plus baseline for starting antipsychotics ie. Olanzapine, Clozapine
TFT’s	Hypothyroidism or hyperthyroidism can present as psychosis
Blood glucose and lipid profile	A baseline for commencing antipsychotics. Metabolic syndrome is common among patients who suffer from psychosis
Electrolytes (plus Ca2+, Mg2+, phosphate)	Underlying metabolic or endocrine disturbances
Renal function (eGFR, creatinine)	Prior to commencing antipsychotics
LFT’s	Prior to commencing antipsychotics and ruling out alcohol-related liver disease
Blood / Urine toxicology	Illicit substances can contribute to a psychotic presentation
Prolactin levels	Prior to commencing antipsychotics
ECG	Prior to commencing antipsychotics
HIV and Syphilis	If sexually transmitted infections are suspected to contribute to the mental state

Autoimmune encephalitis presenting as psychosis: Autoimmune disorders with antibodies secreted against neurotransmitter receptors can present with psychosis. There is evidence for N-methyl-d-aspartate receptor (NMDAR) hypofunction as a central part of the functional dysconnectivity There is also evidence for voltage-gated potassium channel dysfunction. With regard to NMDAR encephalitis: NMDAR antibody testing is more sensitive in CSF than serum. It is more common in females (80%) than males. Anti-NMDAR encephalitis should respond to 3 days of methylprednisolone oral/intravenous, alongside 5 days of plasma exchange. It is recommended to avoid antipsychotics in patients who have anti-NMDAR antibodies due to the risk of neuroleptic malignant syndrome or dystonic reactions.

Dementia

Physical examinations when presented with a patient with dementia can help rule out treatable causes as well as precipitating factors. Examination and investigations could identify signs of a stroke or other neurological disorders than can contribute to dementia.

Assessment can identify pathology such as cardiovascular or renal disease that has a strong overlap with dementia.

A physical examination can help rule out treatable causes of dementia and identify signs of a stroke or other disorders that can contribute to dementia. It can also identify signs of other illnesses, such as heart disease or kidney failure, that can overlap with dementia. If a patient is taking medications that may be causing or contributing to his or her symptoms, the doctor may suggest stopping or replacing some medications to see if the symptoms go away.

Investigation	Purpose
FBC	Infections or inflammatory causes plus baseline for starting antidementia medications
TFT’s	Low T4 or impaired thyroid function can impair cognition
Blood glucose and lipid profile	A baseline for commencing antidementia medications. Metabolic syndrome is common among patients who suffer from dementia
Electrolytes (plus Ca2+, Mg2+, phosphate)	Impaired cognition can present due to deficiencies
Renal function (eGFR, creatinine)	Prior to commencing antidementia medications
LFT’s	Prior to commencing antidementia medications
Lumbar puncture	Sometimes, a lumbar puncture (spinal tap) may be performed to obtain cerebrospinal fluid, which is then analyzed for evidence of Alzheimer’s disease proteins or of certain infections, inflammatory conditions, or other diseases
Vitamin B12	Deficiency can impair cognition
Thiamine and folate	Deficiency can impair cognition
HIV and Syphilis	HIV-associated dementia or neurosyphilis can notably impair cognition and predispose to opportunistic infections.
CT or MRI head	Routine imaging of elderly patients often provides low diagnostic yield, especially for Alzheimer’s disease. It is evident when suspicion of vascular dementia, or medical causes such as haematoma or tumours.

Anorexia Nervosa

Anorexia nervosa presents often with a varying degree of physical and psychosocial morbidity.

Patients with anorexia nervosa (AN) typically have low body weight, intense fear of gaining weight, and a body image disturbance. While more often detected in women, cases of AN in young men may be under-represented.

Organ systems	Pathological findings	Leading systems
CNS	Morphological/function cerebral changes; volume reduction in both cerebral grey and white matter	Cognitive deficits
Dental systems and parotid glands	Impaired dental status, increased risk of dental cavities, increased serum amylase	Dental decay, enlargement of the parotid glands
Endocrine system and reproductive function	Impairement of HPA axis, low T3, hypercortisol	Amenorrhoea in women, hypothyroidism, depression, increased stress levels
Cardiovascular system	Hypotension, bradycardia, arrhythmia	Syncope
Gastrointestinal tract	Impaired gastric emptying, GI ulcers, increased dilation of the stomach	Constipation, upper GI bleeding, ileus
Haematological and immune system	Bone marrow hypoplasia with decreased leucocytes and Ig	Anameia, bacterial infections, impaired immune system
Renal tract	Hypokalaemia, hypophosphataemia, hypernatraemia	Nephrolithiasis, oedema, syncope
Bone	Decreased bone density (osteopenia/osteoporosis)	Bone fractures or spinal compression, associated pain

Electrocardiography

Electrocardiography (ECG) is the process of creating an electrocardiogram, which is a recording of the electrical activity of the heart. It is a heart electrogram, which is a graph of voltage versus time of the electrical activity of the heart recorded with electrodes placed on the skin.

ECG feature:	Summary:
Rate	The average rate is 60-100. Bradycardia is defined as less than 60 beats per minute, while tachycardia is defined as more than 100 beats per minute.
ST section	Myocardial infarction is indicated by an upsloping ST segment (referred to as ST elevation). A low ST segment indicates myocardial ischaemia.
QTc interval	The normal QTc interval range is 0.35-0.45 seconds.
PR interval	A typical PR interval is 0.12 to 0.2 seconds. First-degree heart block is defined as a PR interval that is consistently longer than 0.2s.
T-waves	In some leads, are peaked in hyperkalemia, flat and prolonged in hypokalemia, and inverted in normal, as well as in ischemia and infarction.
U-shaped waves	It can be normal, but it can also be found in hypokalemia.

References:

(1) Hage, M.P. and Azar, S.T. (2012). The Link between Thyroid Function and Depression. Journal of Thyroid Research, [online] 2012, pp.1–8. doi:10.1155/2012/590648.

(2) Balon, R. (2006). Mood, anxiety, and physical illness: body and mind, or mind and body? Depression and Anxiety, 23(6), pp.377–387. doi:10.1002/da.20217.

(3) Bmj.com. (2019). Generalised anxiety disorder – Symptoms, diagnosis and treatment | BMJ Best Practice. [online] Available at: https://bestpractice.bmj.com/topics/en-gb/120.

(4) Zandi, M.S., Irani, S.R., Lang, B., Waters, P., Jones, P.B., McKenna, P., Coles, A.J., Vincent, A. and Lennox, B.R. (2010). Disease-relevant autoantibodies in first episode schizophrenia. Journal of Neurology, 258(4), pp.686–688. doi:10.1007/s00415-010-5788-9.

(5) stanfordhealthcare.org. (n.d.). Laboratory tests. [online] Available at: https://stanfordhealthcare.org/medical-conditions/brain-and-nerves/dementia/diagnosis/laboratory-tests.html.

(6) Zipfel, S., Giel, K.E., Bulik, C.M., Hay, P. and Schmidt, U. (2015). Anorexia nervosa: aetiology, assessment, and treatment. The Lancet Psychiatry, 2(12), pp.1099–1111. doi:10.1016/s2215-0366(15)00356-9.

(7) bestpractice.bmj.com. (n.d.). Log in | BMJ Best Practice. [online] Available at: https://bestpractice.bmj.com/topics/en-gb/440/investigations#firstOrder [Accessed 6 Dec. 2022].